Recovery Degree Research Articles

Analysis of Ice Storm Impact on and Post-Disaster Recovery of Typical Subtropical Forests in Southeast China

Ice storms greatly affect the structure, dynamics, and functioning of forest ecosystems. Studies on the impact of such disasters, as well as the post-disaster recovery of forests, are important contents in forest biology, ecology, and geography. Remote-sensing technology provides data and methods that can support the study of disasters at the large-to-medium scale and over long time periods. This study took Chebaling National Nature Reserve in Guangdong Province, China, as the study area. First, field-survey data and remote-sensing data were comprehensively analyzed to demonstrate the feasibility of replacing the forest stock volume with the mean annual value of the Enhanced Vegetation Index (EVI), to study forest growth and change. We then used the EVI from 2007 to 2017, together with a variety of other remote-sensing and forest sub-compartment data, to analyze the impact of the 2008 ice storm and the subsequent post-disaster recovery of the forest. Finally, we drew the following conclusions: (1) Topography had a considerable effect on disaster impact and forest recovery in Chebaling. The forest at high altitudes (700–1000 m) and on steep slopes (25–40°) was seriously affected by this disaster but had a stronger post-disaster recovery ability. Meanwhile, the hardest-hit area for coniferous forest was higher and steeper than that for broad-leaved forest. (2) In the same terrain conditions, coniferous forests were less affected by the disaster than broad-leaved forests and showed less variation during the post-disaster recovery process. Nevertheless, broad-leaved forests had faster recovery rates and higher recovery degrees; (3) Under the influence of human activities, the recovery and fluctuation degree for planted forest in the post-disaster recovery process was significantly higher than that for natural forest. The study suggests that forest has high disaster resistance and self-recovery ability after the ice storm, and this ability has a strong correlation with the type of forest and the topographic factors such as elevation and slope. At the same time, human intervention can speed up the recovery of forests after disasters.

Evaluation of Waterflood Development Effect by Using Recovery Degree of Recoverable Reserves and Cumulative Water Storage Rate

For water flooded oilfields, the development effect can be given by analyzing the relationship between the recoverable reserves recovery degree and the cumulative water storage rate and water content. Application of recoverable reserves as the basis for evaluating development effects is more comparable than the extent of geological reserves; The cumulative water storage rate is suitable for evaluating the evaluation unit as a whole since its development. Correctly deriving the relationship between the extent of recoverable reserves recovery and the cumulative water storage and water content are the basic conditions for its application.

Analysis of Risk Factors of Recurrent Vertebral Fractures After Percutaneous Vertebroplasty

<i>Background</i>: Investigate the risk factors of recurrent vertebral compression fractures after percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCF). <i>Method</i>: Data of 401 patients with osteoporotic vertebral compression fractures treated by PVP from March 2013 to June 2018 were retrospectively analyzed, and were divided into re-fracture group and nonre-fracture group according to the postoperative recurrence of vertebral compression fractures. The following parameters were observed, including age, gender, bone mineral density (BMD), correction degree of kyphosis, recovery degree of vertebral height, amount of bone cement injected, Pfirrmann classification of adjacent intervertebral disc of hurt vertebral, and bone cement leakage in intervertebral disc. Then, the above parameters were statistically analyzed by univariate and multivariate analysis to explore the risk factors of vertebral recurrent fracture after PVP. <i>Result</i>: Among 401 patients, 34 (34 /401, 8.4%) recurred OVCF after PVP. Statistical analysis showed that the risk of recurrent vertebral fracture increased by 3.732 times (95% CI 1.107-12.581) when Pfirrmann classification of adjacent intervertebral disc was in degeneration grade. The risk of recurrent vertebral fracture was significantly increased by 31.818 times (95% CI 13.384-75.640) when bone cement leakage occurred in intervertebral disc. <i>Conclusion</i>: Pfirrmann classification of adjacent intervertebral disc and bone cement leakage in intervertebral disc are significantly correlated with the recurrence of vertebral fracture after PVP. In PVP operation, avoiding the bone cement leakage in intervertebral disc can significantly reduce the recurrence of vertebral compression fractures.

Primena suve magnetne separacije visokog intenziteta na obogaćivanje niskoprocentne rude gvožđa iz rudnog ležišta Rouina, Alžir

The recent developments of steel and iron industries generated a huge consumption of iron ores which has attracted much attention for utilizing low-grade iron resources to satisfy this increasing demand. The present study focuses on the characterization and enrichment of the low-grade iron ores from Rouina deposit-Ain Defla-. Currently, the ore is used in the cement industry because it is considered a low-grade iron ore. After the sampling process, a physico-chemical and mineralogical characterization was carried out and the results revealed that the sample consists of hematite, limonite and goethite as major opaque oxide minerals whereas silicates as well as clays form the gangue minerals in the sample. The average grade of FeTotal, SiO2 and Al2O3 contents in the raw material collected from the mine of the case study are 30.85%, 23.12% and 7.77% respectively. Processes involving combination of classification, washing and dry high-intensity magnetic separation were carried out to upgrade the low-grade iron ore sample to make it suitable as a marketable product. The sample was first ground and each closed size sieve fractions were subjected to washing followed by drying than dry high intensity magnetic separation and it was observed that limited upgradation is possible. As a result, it was possible to obtain a magnetic concentrate of 54.09% with a recovery degree of 89.30% and yield of 62.82% using a magnetic field intensity equal to 2.4 Tesla at the size fraction [-0.125 +0.063 mm].

Изучение растворимости осадков некоторых лантаноидов в карбонатных средах

The study examines the dissolution process for the precipitates of the rare-earth carbonates and phosphates with a change in the concentration parameters of the system. The objective of the study is to determine the nature of the dissolution process at variable composition of the studied solutions. As a result of the theoretical base analysis, the qualitative and quantitative content of rare-earth metals in red sludge and phosphogypsum is presented, which governs the interest in this problem under consideration. The available techniques for extraction of rare-earth metals from red sludge and phosphogypsum have also been considered, their advantages and disadvantages are presented. A promising carbonate-alkali method for the extraction of rare-earth metals has been considered. Thermodynamic parameters of the system have been calculated to determine the possibility of the process. During the experiment the factors affecting the dissolution process have been examined: the carbonate ion concentration, the nature of the solvent cation and rare-earth metal cation. Carbonates and phosphates of europium, holmium, and neodymium have been considered as the analyzed components. Carbonates and phosphates of neodymium, europium, and holmium have been dissolved in model solutions of K2CO3 with the concentrations of 0.2–4.5 mol/L until reaching equilibrium. The obtained results show the dependence of solubility of the precipitates of rare-earth metals on the solvent nature and concentration. The explored data are presented as solubility isotherms. On the basis of experimental data the values of the extraction degree of a rare-earth metal into the solution have been calculated. For neodymium, europium, and holmium carbonates, the maximum recovery degree αmax is 72.8 %, 81.2 %, 83.0 %, respectively. During the experiment with dissolution of lanthanide phosphates, the following results have been obtained: the maximal degree of neodymium extraction is 60.59%, while for europium it equals 51.66 % and 93.01 % for holmium

Application of seismic architecture interpretation in enhancing oil recovery in late development Stage——Taking meandering river reservoir in Dongying depression as an example

Taking typical meandering river deposits of Ng52+3 in the west 7th block of Gudong Oilfield as an example, the influence of point-bar-sandstone superposition structure on flooding law and remaining oil distribution is studied by means of seismic architecture interpretation under the guidance of point-bar geometry. Meanwhile, the influence of morphological parameters and lithology of lateral accretionary surfaces on remaining oil and development characteristics is discussed. The seismic waveform and amplitude of point-bar boundary sandstones are obvious when they overlap with each other. The connectivity of superimposed zones between boundary sandbodies of point-bars is poor. The remaining oil near the superimposed zones is enriched when base-of-channel sandstone that infills abandonment (PI) and the earliest sandstone at the beginning of migration of the point bars (PI) superimposed with each other. Remaining oil is relatively not enriched when PI sandstones of point-bars are superimposed in superimposed zone. Remaining oil is relatively enriched in the upper point-bar sandstone at the superimposed zone. The effective shielding area effective distance to obstruct fluid flow of mudstone section of lateral accretionary surfaces is 50–80 m along the lateral direction of lateral-accretion surfaces, and the remaining oil is not enriched in the same point bar within the range of 50–80 m around oil and water wells. The physical property section of lateral-accretion surfaces in the middle and lower part of the surfaces has a certain blocking effect on flow and can obviously reduce the recovery degree. Seismic architectural interpretation plays an important role in predicting remaining oil enriched areas and prolonging oil field life in order to improve oil recovery.

Current therapeutic strategies for erectile function recovery after radical prostatectomy – literature review and meta-analysis

Current therapeutic strategies for erectile function recovery after radical prostatectomy – literature review and meta-analysis

The practice and understanding of reconstructing the flow field by the homogenization-flowline method

After a long period of unstable injection and production, the reservoir is distributed within different levels of the advantage seepage area and the weak seepage areac. With the continuous development, especially gradually into the high water content, high recovery degree of the double-high reservoir, saturation field is basically in an almost stable state. For the reservoir of large porous channel and serious flooding, the use of the homogenization field technology can achieve the purpose of adjusting the yield and suction profile, strengthening the balanced utilization, and reconstructing the underground seepage field. Before the reconstruction of the flow field, the flow line was densely distributed in the advantage seepage area, and after the reconstruction of the flow field, the flow line in the well area was evenly distributed. The water injection utilization rate was greatly improved, and the remaining oil was used effectively. On-site examples show that by adjusting the strength of the flat water drive, the daily injection of Gang 5-30 Well was raised from 30 m3 to 100 m3, the distribution of seepage field changed significantly, and the degree of control and utilization of the oil layer was greatly increased.

Recovery characteristics of Bt insecticidal protein and relative physiological mechanisms after high temperature stress termination in square of Bt cotton

The experiments were conducted at Key Laboratory of Genetics and Physiology of Yangzhou University. The conventional cultivar Sikang-1 and hybrid cultivar Sikang-3 were used as the experimental materials. The potted cotton at squaring stage was moved to artificial climatic chamber with 38°C for 72 h , and 38°C for 96 h respectively in 2017 and 2018 cotton growth season, and moved to natural conditions, then the squares were collected to measure the Bt protein concentration and nitrogen metabolic physiology at 0, 12, 24, 48, 72, 96 hours respectively after the high temperature termination. The square Bt insecticidal protein contents were able to recover to the corresponding control level, the time for the recovery was in need of longer as the stressed high temperature period increased. In 72 h high temperature treatment, the square Bt insecticidal protein content could recover to the corresponding control level at 72 h for Sikang-1 and at 48 h for Sikang-3. In 96 h high temperature treatment, the square Bt insecticidal protein content could recover to the corresponding control level at 96 h for Sikang-1 and at 72 h for Sikang-3. There were significantly positive correlations of Bt toxin content with soluble protein content, glutamate pyruvate transaminase activity and glutamate oxaloacetate transaminase activity (the correlation coefficients were 0.964**, 0.981**, and 0.971**, respectively), and significantly negative correlations of Bt toxin content with free amino acid contents, and activitied of protease and peptidase (the correlation coefficients were -0.894**, -0.912**, and -0.834**, respectively). Therefore, the recovery degree of Bt insecticidal protein content of cotton square can be predicted according to the duration of high temperature stress, reasonably controlling Helicoverpa armigera and related pests in production.

Comprehensive Recovery Technology for Te, Au, and Ag from a Telluride-Type Refractory Gold Mine

While extracting gold and silver from telluride-type gold deposits, it is beneficial to develop a comprehensive recovery technology for tellurium. In this paper, we report process mineralogy based on the backward processing technology and the low comprehensive utilization rate of typical telluride-type gold deposits in Xiaoqinling, China. The findings show that tellurium, gold, and silver are the most valuable elements in the ore fissures and gangue minerals and are encapsulated in metallic sulfur ore in the form of altaite, hessite, calaverite, antamokite and natural gold. The flotation method was innovatively applied in this study to comprehensively recover Te, Au and Ag. The results show that when the ore particle size was −0.074 mm (70%), the flotation pulp density was 33%, the pulp pH was 8, and the combined collector (isoamyl xanthate + ethyl thio- carbamate (1:1)) was 120 g/t, in the process involving one rough flotation step, two cleaning flotations and two scavenging flotations as well as a continuous 8 d industrial test, the recovery degree was stable and the average grades of Te, Au, and Ag were 241.61, 90.30, and 92.74 g/t with 95.42%, 97.28%, and 94.65% recovery rates, respectively; thus, excellent recovery degrees were obtained. Compared with the original flotation process, the recovery rates of Te, Au, and Ag were increased by 19.91%, 6.93%, and 5.67%, which boosted the effective enrichment of all valuable elements in the telluride-type gold mine and achieved technological progress.

Direct α-arylation of ketones efficiently catalyzed by Cu-MOF-74

Abstract The activity and reusability of Cu-MOF-74 as heterogeneous catalyst were studied in the Cu-catalyzed C C cross-coupling reaction of 4-iodotoluene (4-IT) with acetylacetone (AcAc) to direct synthesis of α-aryl-ketones. Cu-MOF-74 is characterized by having unsaturated copper sites into its highly porous metal-organic framework that can play a crucial role in catalytic applications. The influence of critical reaction variables such as solvent, reaction temperature, AcAc/4-IT ratio, catalyst concentration and basic agent (type and concentration) were evaluated. High conversions were achieved at 140 °C, 5 mol % of catalyst, AcAc/4-IT ratio of 2:1, DMF as solvent and 1.5 equivalent of Cs2CO3 base. The C-arylation between 4-IT and AcAc proceeded only in the presence of Cu-MOF-74 material, being very low the transformation in absence of the solid catalyst. Cu-MOF-74 material displayed a remarkable structural stability, regarding its XRD patterns and solid recovery degree after several reaction cycles, which was also complemented by the negligible amount of copper leached in the reaction media. This catalyst showed promising results in comparison to other homogeneous and heterogeneous Cu-based catalysts. This work evidences the great potential of MOF materials as heterogeneous catalysts in fine chemistry applications.

Leaching of gold-containing ores with application of oxidation activators

The Article presents the results of studies conducted to process gold-bearing rocks from one of the fields in Kazakhstan. We studied the phase chemical and mineral composition of the ore using semi-quantitative X-ray fluorescent, chemical (assay), electron raster and rational (phase) analyzes. Wefound that the test sample contained 1.4 g/t Au and 0.14 g/t Ag. The granulometric analysis showed that the main gold (36.51%) was concentrated in a class of -2.5 +1.25 mmsize, with 1.42 g/t gold content. The main components of the initial sample composition were quartz 38.9%, albite 20.3%, pyrite 5.8%. we studied thegravity recovery possibility of gold-bearing ore using laboratory equipment, i.e. Knelson KS-MD 3 centrifugal concentrator. We obtained a gold-containing concentrate with 6.04 g/t gold content on a centrifugal concentrator with extraction of 52.65%, and 0,82 g/t gold in gravity tailingsunder the one-stage recovery flow sheet. We determined the optimal leaching parameters for the recovery products (gravity concentrate and gravity tailings) using various oxidation activators. The gold recovery degree was 77.3%with direct gravity concentrate cyanidation, and 85.7%with preliminary oxidation using calcium hypochlorite increasing the gold recoverydegree by 8.4%, when leaching the gravity tailingsusing calcium hypochlorite -73.1%, sodium peroxide - 75.6%, Ascor oxidation activator (AS-45102) - 71.9%.

Uranium sorption from productive solutions prepared by carbonate leaching from peat ore

The uranium sorption by anion exchange resins from productive solutions prepared by carbonate leaching from peat ore was investigated. The uranium recovery from leach liquors decreased during long-time exploitation of ion exchangers due to contamination of resins with humic substances. The alkaline solution of sodium chloride can be used to efficiently regenerate of resins. The resin Purolite A660/4759 had the highest value of full dynamic exchange capacity, which was (36.62 ± 1.10) g U/L of wet settled resin. The desorption process was carried out by ammonium carbonate/bicarbonate mixture solutions with values of uranium recovery degree of (97.41 ± 2.53)%. The degree of uranium precipitation during crystallization of ammonium uranyl carbonate from pregnant solutions was 72%.

Role of Alkali Type in Chemical Loss and ASP-Flooding Enhanced Oil Recovery in Sandstone Formations

Summary Chemical combination flooding techniques, particularly alkali/surfactant/polymer (ASP) flooding, have proved to be effective in enhanced oil recovery (EOR). The development of this flooding technique in the Daqing Oil Field (China) shows that it can prevent production declines and help oil companies increase profits. However, ASP chemical loss and the resulting chromatographic separation in sandstone formations remain as limitations in the practice of ASP flooding. Laboratory investigations have analyzed the behavior and characteristics of chemical loss in sandstone reservoirs recently subjected to strong-base [sodium hydroxide (NaOH)] and weak-base [sodium carbonate (Na2CO3)] ASP flooding. A set of experiments were reasonably designed to study how formulation compositions, slug combination patterns, and heterogeneity affected the chromatographic separation and consumption loss characteristics of chemicals in sandstone reservoirs subjected to ASP flooding. Our investigations determined chemical-loss ratios through various experiments, described the underlying mechanism behind the discovered consumption loss characteristics, and discussed the effects of comparative ASP flooding processes. Furthermore, the incremental oil recovery factor and degree of permeability damage in heterogeneous sandstone reservoirs subjected to strong-base and weak-base ASP flooding processes were assessed and compared. Then, the role of alkali type in chemical loss, EOR efficiency, and reservoir flow assurance in sandstone formations were ascertained for the first time. The results indicated that chemical-loss behaviors and chemical chromatographic separation could be alleviated in a weak-base ASP flooding. In particular, in heterogeneous sandstone reservoirs, the average loss ratios of alkalis and surfactants could be reduced by 9.61% and 15.67%, respectively, compared to the strong-base ASP flooding. A profitable EOR of 20% or more could also be obtained with a weak-base ASP flooding. Moreover, a reduction of approximately 15% in the permeability-damage ratio could be realized in weak-base ASP flooding compared with the strong-base system, and the reservoir flow-assurance issues related to chemical loss could be addressed. The optimal designs for ASP formulations and slug combination patterns could technically and sustainably achieve high oil recovery in sandstone reservoirs with a weak-base ASP flooding. The results help illustrate the chemical combination flooding mechanism and can contribute to the existing knowledge regarding the additive effects of chemicals during the EOR process. Moreover, they are significant for further improving oil displacement efficiency and reducing the injection cost in heterogeneous sandstone reservoirs subjected to the weak-base ASP-flooding process.

Research on sensitivity damage of naturally fractured carbonate reservoirs in Ordos Basin

Understanding mechanisms and performance of formation sensitivity damage in naturally fractured carbonate reservoirs is crucial for avoiding productivity attenuation at any development stage. In this paper, based on the investigation of reservoir microscopic feature, a series of experiments were conducted to systematically evaluate formation sensitivity damage through a multistep coreflood platform. Firstly, the influence of flow velocity on core permeability was studied. Then, coreflood experiments under the condition of beneath the threshold velocity were performed to research the influence of the salinity and PH value for the injected water on core permeability. Finally, four types of cores from Ordos Basin—matrix cores, non-packed cores, semi-packed cores, and fully-packed cores—were used to conduct stress sensitivity damage experiments. Permeability is measured in the process of increasing confining pressure with a constant pore pressure. The experiment results show that the velocity sensitivity of the reservoir is medium to strong and the threshold velocity is 0.28 m/d. The water sensitivity is weak and the average water sensitivity index is 22.62%. There is no alkali sensitivity. The stress sensibilities of these four types of cores ranking from strong to weak are non-packed cores, semi-packed cores, packed cores, and matrix cores. With the decrease in packing degree of core fractures, the stress sensitivity of core permeability increases and the recovery degree of permeability decreases. The influence factors of sensitivity damage are systematically studied and it provides the suggestions for stimulation design and development of naturally fractured carbonate reservoirs in Ordos Basin.

Clinical observation of high tibial osteotomy for knee osteoarthritis:10 years follow-up

To explore long-term following-up clinical effects of lateral closed high tibial osteotomy for the treatment of knee osteoarthritis. Twenty patients with medial unicompartmental knee osteoarthritis were treated with lateral closed high tibial osteotomy and screw fixation from June 2005 to December 2015. Among them, including 17 females and 3 males, aged from 43 to 76 years old with an average of (57.80±8.05) years old. VAS score and KSS score were applied to evaluate recovery degree of pain and function before operation and after operation at 1, 5 and 10 years, and postoperative complications were observed. Sixteen patients were followed-up, the time ranged from 9 to 11(10.0±0.8) years, 4 patients were loss to follow-up. Preoperative VAS score was 7.88±1.15 and decreased to 3.19±0.91, 3.44±0.96, 3.69±1.20 at 1, 5 and 10 years after operation, and there were statistical differences in VAS score between before and after operation at different time points (P<0.05). Clinical score of KSS increased from 61.94±5.74 before opertaion to 75.50±4.62, 80.13±3.97, 77.38±6.40 at 1, 5 and 10 years after operation, and there were statistical differences in clinical score of KSS between before and after operation at different time points(P<0.05); functional score of KSS increased from 62.81±13.03 before operation to 77.50±8.56, 81.88±6.55, 76.88±10.78, and there were statistical differences in functional score of KSS between before and after operation at different time points(P<0.05). All incisions healed well without complications such as fibula nerve injury and fracture nonunion. Lateral closed high tibial osteotomy and screw fixation for knee osteoarthritis could receive good clinical results, stop and delay progress of knee osteoarthritis, and long-term following-up could achieve the same effect as total knee arthroplasty.

Analysis on the influencing factors of imbibition and the effect evaluation of imbibition in tight reservoirs

Abstract To exert the imbibition between cracks and matrix effectively and enhance the development effect of tight oil reservoirs, a physical simulation method for imbibition in different scales of cores is developed by combining a high-pressure large-model physical simulation system and nuclear magnetic resonance technology (NMR) to investigate the influencing factors of imbibition process in tight reservoirs, and construct a quantitative evaluation method for the imbibition in water flooding. The results show that in the process of counter-current imbibition, the lower the permeability, the later the oil droplet precipitation, the longer the imbibition equilibrium time, and the lower the recovery degree. Fractures can effectively expand the area of imbibition and the front edge of imbibition in the contact between the dense matrix and water, reduce the resistance of oil discharge, and improve the imbibition speed and the degree of recovery. The more hydrophilic the rock, the higher the imbibition rate and imbibition recovery of tight rocks. In the process of co-current imbibition, the lower the permeability, the more obvious the imbibition, and the displacement recovery is positively correlated with permeability, while the imbibition recovery is negatively correlated with the permeability. It also shows that the imbibition distance of the cyclic water injection is greater than that of the counter-current imbibition, and the higher the permeability and the injection multiple, the longer the imbibition distance. The combination of large-scale volume fracturing with changing reservoir wettability and cyclic water injection is conducive to improving the imbibition ability of tight reservoirs.

The determination of α-glucosidase activity through a nano fluorescent sensor of F-PDA−CoOOH

A sensitive nanocomplex probe prepared from fluorescent polydopamine nanoparticles (F-PDA) and cobalt oxyhydroxide (CoOOH) nanosheets was established for the determination of α-glucosidase activity. In this detection system, the fluorescence of F-PDA was firstly quenched by CoOOH nanosheets based on fluorescence resonance energy transfer (FRET). Subsequently, ascorbic acid was produced from 2-O-α-d-glucopyranosyl-l-ascorbic acid which was selectively hydrolyzed by α-glucosidase. CoOOH was reduced to Co2+ by the released ascorbic acid, which resulted in the recovery of F-PDA nanoparticles fluorescence. In consequence, α-glucosidase activity was determined by the fluorescence recovery degree of the F-PDA nanoparticle. This fluorescent method showed a good linear relationship with the activity of α-glucosidase from 2 to 80 U L−1 and low detection limit of 1.65 U L−1 (S/N = 3). This fluorescence probe with high selectivity and sensitivity demonstrated a remarkable applicability in human serum samples and provided an alternative for α-glucosidase inhibitors screening in the discovery of anti-diabetes drugs.

MON-053 CLINICAL AND PATHOLOGICAL CHARACTERISTICS OF IgA NEPHROPATHY WITH AKD

IgA nephropathy is one of the most common types of primary glomerulonephritis worldwide.It was found that the creatinine of IgA nephropathy could increase in a short time even reaching the diagnostic standard of acute kidney disease（AKD）in clinical work. However, the factors for the occurrence in these patients were unclear. Here,we did a research to explore the clinical features and kidney pathological characteristics of IgA nephropathy patients with AKD and the related factors influencing its recovery. Patients between 2011 and 2016 taken from the First Affiliated Hospital of Zhengzhou University were enrolled in the study.The number of renal glomeruli in all cases was more than or equal to 10.The secondary IgA nephropathy such as systemic lupus erythematosus, purpura nephritis, chronic liver diseases was not included.The 2012 KDIGO guidelines were adopted as the criteria to screen the IgA nephropathy patients with AKD. The baseline data, clinical and renal pathological data were collected.According to the degree of the decline of estimated glomerular filtration rate(eGFR), the IgA nephropathy patients with AKD were divided into three groups with the eGFR decreased by 35-50% in group A, 51-75% in group B, and 76% or more in group C.Then according to the recovery degree of the renal function, the patients were divided into two groups with the recovery group (fully recovery of renal function or partial recovery) and the non-recovery group(no obvious change of renal function or progression of renal function).The clinical features and kidney pathological characteristics of the three groups and the related factors affecting their recoveries were analyzed. A total of 1855 patients were included of which 128 patients occurred to AKD, accounting for 6.9%.There were significant differences in calcium, phosphorus,hemoglobin,albumin,urea nitrogen and urine leukocyte in the three groups (p < 0.05).We followed up the IgA nephropathy patients with AKD for 6 months and found that the creatinine level of 26 patients was not better or even progressed compared with the peak of creatinine during hospitalization, while the creatinine level of 102 patients was lower or completely restored to the baseline.High blood pressure and large amount of proteinuria are the factors that affect the recovery of renal function of AKD.At the same time, we take these patients for a long-term follow-up with the average follow-up time to 3.8 years with the result that 35 patients entered end-stage renal disease(ESRD) or died. The degree of decreased glomerular filtration rate in IgA nephropathy patients with AKD is related to clinical and pathological characteristics and IgA nephropathy patients occurred with AKD are more likely to enter the ESRD.

Study on Deformation and Permeation Properties of Gas-Containing Fractured Rock

In this paper, we investigated the gas permeation properties of fractured rock during the process of stage load axial stress and cyclic load and unload confining pressure and come to some conclusions as follows: (1) the relationship between radial strain and deviatoric stress satisfied the quadratic polynomial function, and the relationship between permeability and deviatoric stress satisfied the exponential function under different axial stress levels; (2) in the staged load axial stress process, the axial strain-deviatoric curves of specimens conform to the quadratic polynomial function. The axial strain-deviatoric curves of specimens conform to linear function when confining pressure is 8.6 MPa or 2.0 MPa at different axial stress levels; (3) we used the permeability damage rate and maximum permeability damage rate to evaluate the recovery degree and reduction extent of permeability; (4) we used the volume expansion ratio and the maximum volume expansion ratio to evaluate the expansion degree and increase extent of rock samples’ volume.