Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 48
Filter
Add more filters

Country/Region as subject
Affiliation country
Publication year range
1.
J Pept Sci ; 28(12): e3443, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35802249

ABSTRACT

Peptides have gained popularity in the global market during recent years and have been placed between small molecule drugs and biologics. However, little is known about the comprehensive landscape of peptide drugs in obstetrics and gynaecology. Herein, we analysed new peptide drug-related clinical trials in obstetrics and gynaecology registered on ClinicalTrials.gov. The number and percentage were used for statistical analysis, and a time trend analysis was conducted by calculating the annual growth rate. We aimed to provide the first overview of the changing landscape and status of global peptide drugs in this prospective field, including exploring drug targets, the cutting-edge oncotherapy of peptide vaccines and peptide-drug conjugates, and unsolved challenges with oral administration.


Subject(s)
Biological Products , Gynecology , Obstetrics , Female , Humans , Pregnancy , Peptides/therapeutic use , Pharmaceutical Preparations , Clinical Trials as Topic
2.
Cell Physiol Biochem ; 46(3): 1209-1217, 2018.
Article in English | MEDLINE | ID: mdl-29672293

ABSTRACT

BACKGROUND/AIMS: Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes mellitus (DM). Because of its controversial pathogenesis, DPN is still not diagnosed or managed properly in most patients. METHODS: In this study, human lncRNA microarrays were used to identify the differentially expressed lncRNAs in DM and DPN patients, and some of the discovered lncRNAs were further validated in additional 78 samples by quantitative realtime PCR (qRT-PCR). RESULTS: The microarray analysis identified 446 and 1327 differentially expressed lncRNAs in DM and DPN, respectively. The KEGG pathway analysis further revealed that the differentially expressed lncRNA-coexpressed mRNAs between DPN and DM groups were significantly enriched in the MAPK signaling pathway. The lncRNA/mRNA coexpression network indicated that BDNF and TRAF2 correlated with 6 lncRNAs. The qRT-PCR confirmed the initial microarray results. CONCLUSION: These findings demonstrated that the interplay between lncRNAs and mRNA may be involved in the pathogenesis of DPN, especially the neurotrophin-MAPK signaling pathway, thus providing relevant information for future studies.


Subject(s)
Diabetic Neuropathies/pathology , RNA, Long Noncoding/metabolism , Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/metabolism , Cluster Analysis , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/pathology , Diabetic Neuropathies/etiology , Diabetic Neuropathies/metabolism , Down-Regulation , Glucose Tolerance Test , Humans , Mitogen-Activated Protein Kinases/metabolism , Oligonucleotide Array Sequence Analysis , RNA, Messenger/metabolism , Signal Transduction , TNF Receptor-Associated Factor 2/genetics , TNF Receptor-Associated Factor 2/metabolism , Up-Regulation
3.
J Shoulder Elbow Surg ; 26(2): e44-e51, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28104095

ABSTRACT

BACKGROUND: Radical release for severe stiff elbows may lead to instability. Hinged external fixation is used to treat unstable elbows. We hypothesized that extensive open release combined with a distal radius-positioned hinged external fixator would have good performance and low complications rate in treating severe elbow stiffness. Thus, the efficacy and security of this technique were assessed in this study. METHODS: We retrospectively reviewed 38 post-traumatic elbows with severe stiffness that underwent arthrolysis between February 2011 and February 2014. All patients were assessed as having elbow instability after complete arthrolysis. Ligament repair was combined with implantation of a hinged external fixator (fixed to the humerus and distal radius) to maintain elbow stability. Flexion arc, forearm rotation, Mayo Elbow Performance Score, elbow stability, and radiographs were evaluated preoperatively and postoperatively, and complications were documented. RESULTS: Mean follow-up was 31 months. Significant improvement was noted in flexion-extension arc (from 27° to 126°), forearm rotation (from 148° to 153°), and mean Mayo Elbow Performance Score (from 68 points to 96 points). Mean pronation arc decreased from 66° preoperatively to 6° at 1.5 months of follow-up and showed a transient reduction during first 6 months postoperatively. Pin-related infection occurred in 2 patients, which was cured with conservative treatment. Two patients had moderate instability after removal of the fixator and regained stability at the 12-month follow-up. At the last follow-up, complications included ulnar nerve paralysis in 3, recurrence of heterotopic ossification in 1, and moderate pain in 1. CONCLUSIONS: Complete open release combined with a distal radius-positioned hinged external fixator is an effective treatment for severe stiff elbows. This technique had a low complication rate.


Subject(s)
Elbow Joint , External Fixators , Fracture Fixation/instrumentation , Joint Instability/surgery , Adolescent , Adult , Female , Fracture Fixation/methods , Humans , Joint Instability/diagnostic imaging , Joint Instability/etiology , Male , Middle Aged , Radiography , Range of Motion, Articular , Retrospective Studies , Treatment Outcome , Young Adult
4.
Opt Express ; 24(8): 8411-9, 2016 Apr 18.
Article in English | MEDLINE | ID: mdl-27137279

ABSTRACT

We report a prototypical device of CH3NH3PbCl3 film ultraviolet photodetectors that were fabricated with a coplanar metal-semiconductor-metal Au interdigital electrode configuration. Pure phase CH3NH3PbCl3 films with a good crystallinity were formed by a hybrid sequential deposition process featured with inter-diffusion of PbCl2 and CH3NH3Cl upon annealing. The CH3NH3PbCl3 film photodetector exhibits a high responsivity of 7.56 A /W at 360 nm, a ultraviolet/visible rejection ratio (R360 nm/R500 nm) was about two orders of magnitude and fast response speed with a rising time of 170 µs and a decay time of 220 µs. All the above results demonstrate CH3NH3PbCl3 film photodetector as a competitive candidate in the application of visible blind UV detectors.

5.
Phys Chem Chem Phys ; 18(27): 18607-13, 2016 Jul 21.
Article in English | MEDLINE | ID: mdl-27346149

ABSTRACT

The interface chemistry and evolution of the evaporated perovskite films on ITO, pedot/ITO, Si and glass substrates are studied. As evidenced by X-ray diffraction and X-ray photoemission spectroscopy (XPS) results, the PbI2 phase is found to be inevitably formed at the very initial growth stage, even under the conditions of a MAI-rich environment. The extremely low binding energy of adsorbed MAI particles on all the above substrates, as compared to that of PbI2 particles, is responsible for the presence of the PbI2 phase at the interface. The formation of both hole and electron barriers at the interface of PbI2/MAPbI3, as evidenced by XPS measurements, could block carrier transport into the electrode and thus deteriorate solar cell performance. This result reveals the origin of the poor performance of perovskite solar cells (PSCs) by the vacuum evaporation method, and may help to improve the performance of PSCs made using the vacuum evaporation method.

6.
Eur Neurol ; 73(1-2): 5-12, 2015.
Article in English | MEDLINE | ID: mdl-25358603

ABSTRACT

BACKGROUND: To assess the safety and efficacy of rasagiline for the treatment of Parkinson's disease (PD) among individuals currently receiving levodopa. METHODS: A systematic literature search was conducted to identify randomised controlled trials (RCT) comparing rasagiline with placebo/no treatment in individuals with PD currently receiving levodopa. Outcome measures included improvement in motor functions; symptomatic improvement; improvement in quality of life; adverse effects. Random-effect meta-analytical techniques were conducted for the outcome measure and subgroup analyses. RESULTS: Three RCTs were included (n = 1002). The results showed significantly greater improvements in daily 'on' time without dyskinesia in levodopa-treated participants with idiopathic PD receiving 1 mg/day rasagiline compared to placebo (n = 712, 2 RCTs, MD 0.80, CI 0.45 to 1.15; p < 0.00001), and significantly greater improvements in Unified Parkinson's Disease Rating Scale motor performance scores during 'on' time in participants receiving 0.5-1 mg/day rasagiline (0.5 mg/day: n = 282, MD -2.91, CI -4.59 to -1.23; p = 0.0007; 1 mg/day: n = 712, 2 RCTs, MD -2.91, CI -4.02 to -1.80; p < 0.00001). There were no significant differences in adverse effects. CONCLUSION: 0.5 to 1 mg/day rasagiline in addition to levodopa is a safe and well-tolerated combination therapy for individuals with Parkinson's disease.


Subject(s)
Antiparkinson Agents/administration & dosage , Indans/administration & dosage , Neuroprotective Agents/administration & dosage , Parkinson Disease/drug therapy , Drug Therapy, Combination , Female , Humans , Levodopa/administration & dosage , Male , Outcome Assessment, Health Care , Quality of Life , Randomized Controlled Trials as Topic
7.
J Shoulder Elbow Surg ; 24(8): 1165-71, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26189802

ABSTRACT

BACKGROUND: Post-traumatic heterotopic ossification (HO) around the elbow may severely impair joint function. Although surgical excision is effective at restoring range of motion (ROM), traditional surgical treatment is postponed for at least 1 year to prevent recurrence, which leads to secondary contracture of the elbow. Because the optimal timing of resection is controversial, our study was performed to compare recurrence and elbow function between early and late excision in our patients to determine whether the delay is necessary. METHODS: We retrospectively reviewed 164 patients during a 4-year period. In the control group (112 patients), HO was excised at an average of 23.0 months after initial injury (range, 9-204 months); in the early excision group (52 patients), resection was performed at an average of 6.1 months (range, 3-8 months). HO recurrence was assessed by the Hastings classification system. Final ROM and Mayo Elbow Performance Scores were also evaluated. RESULTS: Recurrent HO was observed in 30 of 112 patients (26.8%) in the control group and 15 of 52 (28.9%) in early excision group. No significant difference in HO recurrence was found between the 2 groups (P = .942). Moreover, there were no notable differences regarding ROM, Mayo Elbow Performance Scores, and complications postoperatively. CONCLUSIONS: Early excision associated with early exercise is effective for the treatment of HO aiming at a low recurrence rate and satisfactory function. The conventional surgical delay of more than 1 year may be shortened.


Subject(s)
Elbow Injuries , Elbow Joint/surgery , Ossification, Heterotopic/surgery , Time-to-Treatment , Adolescent , Adult , Aged , Case-Control Studies , Female , Humans , Male , Middle Aged , Ossification, Heterotopic/etiology , Ossification, Heterotopic/prevention & control , Range of Motion, Articular , Recurrence , Retrospective Studies , Young Adult
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1421-4, 2014 May.
Article in Zh | MEDLINE | ID: mdl-25095451

ABSTRACT

In M star population, some special objects, which may be of magnetic activity, may be giant stars, or may be of other rare properties, are very important for the follow-up observation and the scientific research on galactic structure and evolution. For local bias of M-type star spectral characteristic lines contained in subspace, a late-type star spectra outlier data mining system is given in the present paper. Firstly, for the sample of M stellar spectral characteristic lines indices, its distribution characteristics in attribute spaces are measured by using the sparse factor and sparsity coefficient, and then this sample is discretized and dimension-reduced to the spectral subspace. Secondly, local outlier subspaces are extracted by PSO (particle swarm optimization) algorithm and identified. Additionally, the effects of sparse coefficient and sparse factor on the number of outliers are discussed by experiments on the sample of SDSS M stellar spectral line index set, and the outliers are compared with spectral type provided by SDSS. In this way, the feasibility and value of this system were validated.

9.
Ying Yong Sheng Tai Xue Bao ; 35(1): 55-61, 2024 Jan.
Article in Zh | MEDLINE | ID: mdl-38511440

ABSTRACT

Improving soil fertility is one of the key approaches for ecological restoration of the wind-sand area in northwest Liaoning Province. Taking wind-sand area in northwest Liaoning Province as test object, we conducted a fertilization experiment with treatments of inorganic fertilizer (nitrogen, phosphorus and potassium fertilizers), organic fertilizer, combined application of organic and inorganic fertilizers, and organic fertilizer combined with a biologically organic matrix (γ-polyglutamic acid), and no fertilizer as control. We measured soil organic matter content and extractable cations concentrations, vegetation coverage, and biomass under different fertilization treatments and determine the suitable fertilization mode. The results showed that compared to the control, inorganic fertilizer rapidly increased vegetation coverage and biomass, but high levels of inorganic fertilizer (150 kg N·hm-2) led to soil acidification and Ca2+ leaching. Organic fertilizer increased soil organic matter content, exchangeable K+, Ca2+, and Mg2+ contents, as well as coverage and biomass vegetation, especially combined with γ-polyglutamic acid. Overall, the combination of low levels of inorganic fertilizer (50 kg N·hm-2) and moderate levels of organic fertilizer (30000 kg·hm-2) was the best fertilization practice for the rapid and stable restoration of grassland in wind-sand area. Moreover, the extra addition of γ-polyglutamic acid (60 kg·hm-2)could effectively improve soil fertility.


Subject(s)
Agriculture , Soil , Agriculture/methods , Fertilizers , Sand , Grassland , Polyglutamic Acid , China , Nitrogen/analysis , Fertilization
10.
Acta Trop ; 254: 107163, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38428630

ABSTRACT

Coxiella burnetii is the causative agent of zoonotic Q fever. Animals are the natural reservoirs of C. burnetii, and domestic livestock represent the major sources of human infection. C. burnetii infection in pregnant females may causes abortion during late pregnancy, whereby massive shedding of C. burnetii with abortion products becomes aerosolized and persists in the environment. Therefore, monitoring and surveillance of this infection in livestock is important for the prevention of the C. burnetii transmission. Previous serological surveys have shown that C. burnetii infection is endemic in livestock in China. However, few data are available on the diagnosis of C. burnetii as a cause of abortion by molecular methods in livestock. To get a better understanding of the impact of C. burnetii infection on domestic livestock in China, a real-time PCR investigation was carried out on collected samples from different domestic livestock suffering abortion during 2021-2023. A total of 338 samples collected from eight herds of five livestock species were elected. The results showed that 223 (66 %) of the collected samples were positive for C. burnetii DNA using real-time PCR. For the aborted samples, 82 % (128/15) of sheep, 81 % (34/42) of goats, 44 % (15/34) of cattle, 69 % (18/26) of camels, and 50 % (17/34) of donkeys were positive for C. burnetii. Besides, 44 % (8/18) and 4 % (1/25) of asymptomatic individuals of sheep and donkey were also positive for C. burnetii. In addition, the positive samples were further confirmed by amplification and sequencing of the C. burnetii-specific isocitrate dehydrogenase (icd) gene. Phylogenetic analysis based on specific gene fragments of icd genes revealed that the obtained sequences in this study were clustered into two different groups associated with different origin of hosts and geographic regions. This is the first report confirming that C. burnetii exists in aborted samples of sheep, goats, cattle, donkeys and camels in China. Further studies are needed to fully elucidate the epidemiology of this pathogen in livestock as well as the potential risks to public health.


Subject(s)
Coxiella burnetii , Goats , Livestock , Q Fever , Real-Time Polymerase Chain Reaction , Animals , Coxiella burnetii/genetics , Coxiella burnetii/isolation & purification , Coxiella burnetii/classification , China/epidemiology , Q Fever/veterinary , Q Fever/microbiology , Q Fever/epidemiology , Livestock/microbiology , Sheep , Female , Goats/microbiology , Abortion, Veterinary/microbiology , Cattle , Pregnancy , DNA, Bacterial/genetics , Sheep Diseases/microbiology , Sheep Diseases/epidemiology
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 237-40, 2013 Jan.
Article in Zh | MEDLINE | ID: mdl-23586264

ABSTRACT

Automatic classification and analysis of observational data is of great significance along with the gradual implementation of LAMOST Survey, which will obtain a large number of spectra data. In classification rules extracted, there is often a great deal of redundancy which will reduce the classification efficiency and quality seriously. In the present paper, a post-processing method of star spectra classification rule based on predicate logic is presented by using predication to describe the classification rules and logical reasoning to eliminate redundant rules. In the end, some experimental results on LAMOST's stellar spectra data show that, with no classification accuracy reduction, the efficiency of auto classification is significantly improved.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(10): 2875-8, 2013 Oct.
Article in Zh | MEDLINE | ID: mdl-24409754

ABSTRACT

Frequent pattern, frequently appearing in the data set, plays an important role in data mining. For the stellar spectrum classification tasks, a classification rule mining method based on classification pattern tree is presented on the basis of frequent pattern. The procedures can be shown as follows. Firstly, a new tree structure, i. e., classification pattern tree, is introduced based on the different frequencies of stellar spectral attributes in data base and its different importance used for classification. The related concepts and the construction method of classification pattern tree are also described in this paper. Then, the characteristics of the stellar spectrum are mapped to the classification pattern tree. Two modes of top-to-down and bottom-to-up are used to traverse the classification pattern tree and extract the classification rules. Meanwhile, the concept of pattern capability is introduced to adjust the number of classification rules and improve the construction efficiency of the classification pattern tree. Finally, the SDSS (the Sloan Digital Sky Survey) stellar spectral data provided by the National Astronomical Observatory are used to verify the accuracy of the method. The results show that a higher classification accuracy has been got.

13.
Front Chem ; 11: 1114970, 2023.
Article in English | MEDLINE | ID: mdl-36825226

ABSTRACT

Drug discovery is a costly and time-consuming process with a very high failure rate. Recently, click chemistry and computer-aided drug design (CADD) represent popular areas for new drug development. Herein, we summarized the recent updates in click and computational chemistry for drug discovery and development including clicking to effectively synthesize druggable candidates, synthesis and modification of natural products, targeted delivery systems, and computer-aided drug discovery for target identification, seeking out and optimizing lead compounds, ADMET prediction as well as compounds synthesis, hopefully, inspires new ideas for novel drug development in the future.

14.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1834-1844, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37694467

ABSTRACT

Nitrogen deposition and summer precipitation in eastern Inner Mongolia are predicted to increase in recent decades. However, such increases in nitrogen inputs and precipitation may not be continuous under the future new patterns of global change, with the direction and magnitude of which may change or weaken. The legacy effects of nitrogen and water addition after cessation on ecosystems are still unclear. Based on a 13-year nitrogen and water addition experiment in temperate grassland of northern China, we examined the short-term (2 years) legacy effects of historical nitrogen and water addition on soil physicochemical properties and microbial properties after the cessation of nitrogen and water addition in the 14th year. The results showed that the positive effects of historical nitrogen addition on most of soil nutrient variables diminished after two years of cessation, including ammonium nitrogen, nitrate nitrogen, dissolved organic carbon and nitrogen, and Olsen-P concentrations. In contrast, there were legacy effects on soil microbial characteristics. For example, the historical nitrogen input of 15 g N·m-2·a-1 reduced microbial biomass carbon, respiration, and alkaline phosphomonoesterase activity by 73.3%, 81.9%, and 70.3% respectively. It implied that microbial parameters restored slowly in comparison with soil nutrients, showing a hysteresis effect. Results of Pearson's correlation and redundancy analysis showed that the legacy effects of historical nitrogen addition on microbial parameters could be attributed to the negative effects of nitrogen addition on soil pH. Historical water addition showed significant legacy effects on soil pH, ammonium nitrogen, dissolved organic carbon and nitrogen, respiration, and soil enzyme activities, which significantly interacted with historical nitrogen addition. These results are of great significance to predict the changes in grassland ecosystem functions and services under the local environmental improvement conditions, and to reveal the restoration mechanism of degraded grassland.


Subject(s)
Dissolved Organic Matter , Nitrogen , Ecosystem , Grassland , Carbon , Soil , Water
15.
J Pediatr (Rio J) ; 99(2): 161-167, 2023.
Article in English | MEDLINE | ID: mdl-35995125

ABSTRACT

OBJECTIVE: To investigate the optimal timing of initial intravenous immunoglobulin (IVIG) treatment in Kawasaki disease (KD) patients. METHODS: KD patients were classified as the early group (day 1-4), conventional group (day 5-7), conventional group (day 8-10), and late group (after day 10). Differences among the groups were analyzed by ANOVA and Chi-square analysis. Predictors of IVIG resistance and the optimal cut-off value were determined by multiple logistic regression analyses and receiver operating characteristic (ROC) curve analysis. RESULTS: There were no significant differences in IVIG resistance among the 4 groups (p = 0.335). The sensitivity analysis also confirmed no difference in the IVIG resistance between those who started the initial IVIG ≤ day 7 of illness and those who received IVIG >day 7 of illness (p = 0.761). In addition, patients who received IVIG administration more than 7 days from the onset had a higher proportion of coronary artery abnormalities (p = 0.034) and longer length of hospitalization (p = 0.033) than those who started IVIG administration less than 7 days. The optimal cut-off value of initial IVIG administration time for predicting IVIG resistance was >7 days, with a sensitivity of 75.25% and specificity of 82.41%. CONCLUSIONS: IVIG therapy within 7 days of illness is found to be more effective for reducing the risk of coronary artery abnormalities than those who received IVIG >day 7 of illness. IVIG treatment within the 7 days of illness seems to be the optimal therapeutic window of IVIG. However, further prospective studies with long-term follow-up are required.


Subject(s)
Immunoglobulins, Intravenous , Mucocutaneous Lymph Node Syndrome , Humans , Infant , Immunoglobulins, Intravenous/therapeutic use , Mucocutaneous Lymph Node Syndrome/drug therapy , Retrospective Studies , Prospective Studies
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 255-8, 2012 Jan.
Article in Zh | MEDLINE | ID: mdl-22497171

ABSTRACT

Variable star is very important for mankind studying cosmic origin and evolution. For studying variable star, the chief difficulty results from the filtration and identification of variable star, that is how to validly identify variable star spectra from large high-dimensional star spectra data. The traditional outlier definition tries to find the difference between the outlier data and the general model by different ways, and then the result is quantitatively analyzed and filtrated. However, the time complexity of this method is over size and its results are inscrutable and unaccountable. Information entropy is a measure of the uncertainty associated with a random variable. In the present paper, information entropy is imported as the standard of dataset common mode. A novel method is proposed to identify the variable star spectrum rapidly based on information entropy. The time complexity of this method is observably reduced and the man-made impact is effectively overcome. The preliminary experimental results based on Sloan star spectrum data show that the method is workable for rapid identification of variable star spectrum.

17.
Hum Vaccin Immunother ; 18(5): 2062982, 2022 11 30.
Article in English | MEDLINE | ID: mdl-35687860

ABSTRACT

Peptide vaccine are a type of immunotherapy that are synthesized according to the amino acid sequence of known or predicted tumor antigen epitopes. They are safe and well tolerated and have shown exciting results in gynecologic oncology. However, no peptide vaccine has yet been licensed in this field. This review examines peptide vaccine clinical trials in gynecology registered on ClinicalTrials.gov through January 1, 2022, analyzes the global progress and current achievements of peptide vaccines in gynecology, and explores the efforts focused on devising new methods to boost immunotherapeutic outcomes, including the use of adjuvants, multi-epitope vaccines, combinations of helper T cell epitopes, personalized peptide vaccines, synthetic long peptides, new peptide delivery, and combination therapy.


Subject(s)
Cancer Vaccines , Genital Neoplasms, Female , Epitopes, T-Lymphocyte , Female , Genital Neoplasms, Female/therapy , Humans , Peptides , Vaccines, Subunit/therapeutic use
18.
Ying Yong Sheng Tai Xue Bao ; 33(2): 369-377, 2022 Feb.
Article in Zh | MEDLINE | ID: mdl-35229510

ABSTRACT

Reasonable nutrient and water management is effective ways to improve productivity and biodiversity of degraded grasslands. However, little is known about the effects of nutrient and water addition on soil inorganic phosphorus (P) fractions in old-field grasslands. Based on a field experiment with nutrient addition (N: 10 g·m-2·a-1, P: 10 g·m-2·a -1) and water addition (180 mm water irrigated during plant growing season) in Duolun County, Inner Mongolia in 2005, we examined the changes of inorganic P fractions and Olsen-P contents in the topsoil (0-10 cm). Results showed that 11-year P addition significantly increased total inorganic P (TIP) content, and that exogenous P was mostly transformed into calcium phosphate (Ca-P: 62.6%-69.2%), and then into aluminium phosphate (Al-P: 19.9%-25.1%), ferric phosphate (Fe-P) and occluded P (O-P). Phosphorus incorporated with nitrogen (N) addition significantly increased Fe-P and Al-P contents by declining soil pH and activating Fe3+ and Al3+ in soil. Water addition alone significantly increased Fe-P, Al-P, and decalcium phosphate (Ca10-P) fractions, and the contents of Fe-P, Al-P, octacalcium phosphate (Ca8-P), and Ca10-P were greater in P incorporated with water treatment than in P addition alone. There was no difference of each inorganic P fraction between P incorporated with N and water treatment and P incorporated with N treatment. Phosphorus and P incorporated with N additions significantly increased soil Olsen-P content, while water addition significantly decreased soil Olsen-P content under P addition alone and P incorporated with N treatment. In the calcareous soils, calcium superphosphate addition could enhance soil inorganic P pool through increasing Ca-P fraction.


Subject(s)
Grassland , Soil , Nitrogen , Nutrients , Phosphorus/chemistry , Soil/chemistry
19.
Ying Yong Sheng Tai Xue Bao ; 31(5): 1579-1586, 2020 May.
Article in Zh | MEDLINE | ID: mdl-32530236

ABSTRACT

Increasing nitrogen (N) deposition results in soil acidification in grasslands. Acid buffering capacity of soil is a critical index evaluating soil acidification, the response of which to N input is regulated by precipitation and concentration of other limiting elements. To explore the responses of soil acidification to N, phosphorus (P), and water inputs, we conducted a 13-year field experiment in an old-field grassland and calculated the acid buffering capacity (ABC) and acid neutralizing capacity (ANC) at the reference of pH=5.0 (ANCpH5.0) and 4.0 (ANCpH4.0), using quadratic curve fitting model. The results showed that, without water addition, single N addition or combined with P addition significantly decreased soil pH, ANCpH5.0 and ANCpH4.0, whereas single P addition had no significant effect on soil pH, ANCpH5.0 or ANCpH4.0. With water addition, the addition of N or combined with P decreased soil pH, ANCpH5.0 and ANCpH4.0, whereas P addition decreased soil pH, increased ANCpH4.0, without effect on ANCpH5.0. In contrast with treatments without water addition, water addition had positive effects on soil pH, ANCpH5.0 and ANCpH4.0. For soils with different initial soil pH values, it was better to select ANC rather than ABC as an index to evaluate soil anti-acidification capacity.


Subject(s)
Grassland , Soil , Nitrogen , Phosphorus , Water
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(4): 1137-41, 2009 Apr.
Article in Zh | MEDLINE | ID: mdl-19626920

ABSTRACT

A novel high-dimensional clustering algorithm is proposed. On the basis of this, a two-stage fuzzy clustering approach, named TSPFCM, is presented. On the first stage, data is clustered by a new clustering method. On the second stage, the result of the first stage is taken as the initial cluster centers, and PSO mechanism is inducted into fuzzy clustering to solve the locality and the sensitiveness of the initial condition of Fuzzy C-means Clustering. The running results of the system show that it is feasible and valuable to apply this method to mining the clustering in spectrum data.

SELECTION OF CITATIONS
SEARCH DETAIL