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Background: In recent years, a kind of drilling method of solid-liquid separation combined with pulsating vacuum formed by vibrating screen and compressed air injection has emerged in oil drilling, which profoundly improves the gas, solid, and liquid separation ability of the drilling fluid vibration screen. Objective: Based on the above ideas, a kind of hydrocyclone used for gas-liquid separation with the pulsating feed boundary was proposed. The separation performance of gas-liquid hydrocyclone may change significantly due to the mixed pulsation of the gas-liquid fluid transported by the jet pump. Therefore, the flow characteristics of the pulsating feed hydrocyclone need to be analyzed and explored to provide basic data for further improvement of the structure. Methods: The development status of cyclone separators are summarized through related literature and patent investigation. The Computational Fluid Dynamics (CFD) software ANSYS Fluent 2019 R3 is used to analyze the flow field characteristics and optimize the parameters of the hydrocyclone with stable feed. Then, the programming by the User-Define-Function (UDF) of Fluent is used to simulate the flow field of the separator under the condition of pulsating feed. Meanwhile, the flow field analysis and parameter optimization are carried out accordingly. Results: The optimal parameters in a stable state and pulsed state are obtained from the analysis of the efficiency curve. The results show that the flow field can be stabilized in the pulsating feed state, and the sinusoidal pulsing with a frequency of 0.4 Hz is used to achieve the highest separation efficiency, i.e., 85.5%. Conclusion: The separators with pulsating feed and stable feed have similar flow field characteristics, and the optimal structural parameters under pulsating feed are obtained. Compared with the stable feed condition, the pulsating feed condition can connect multiple cyclone separators, which can separate more drilling fluid in unit time and improve the work efficiency. It has strong practicability, which provides a critical foundation for structure optimization in the future.

Robotic grasping aims to detect graspable points and their corresponding gripper configurations in a particular scene, and is fundamental for robot manipulation. Existing research works have demonstrated the potential of using a transformer model for robotic grasping, which can efficiently learn both global and local features. However, such methods are still limited in grasp detection on a 2D plane. In this paper, we extend a transformer model for 6-Degree-of-Freedom (6-DoF) robotic grasping, which makes it more flexible and suitable for tasks that concern safety. The key designs of our method are a serialization module that turns a 3D voxelized space into a sequence of feature tokens that a transformer model can consume and skip-connections that merge multiscale features effectively. In particular, our method takes a Truncated Signed Distance Function (TSDF) as input. After serializing the TSDF, a transformer model is utilized to encode the sequence, which can obtain a set of aggregated hidden feature vectors through multi-head attention. We then decode the hidden features to obtain per-voxel feature vectors through deconvolution and skip-connections. Voxel feature vectors are then used to regress parameters for executing grasping actions. On a recently proposed pile and packed grasping dataset, we showcase that our transformer-based method can surpass existing methods by about 5% in terms of success rates and declutter rates. We further evaluate the running time and generalization ability to demonstrate the superiority of the proposed method.

Soil columns were designed to investigate the vertical migration of Cd in Indian mustard (IM) and tall fescue (TF). The TF biomass was greater than the IM biomass, and the Cd content in IM was higher in the shoots but lower in the roots than that in TF. Both IM and TF released N and absorbed P and K during outdoor growth, differing from the results of the previous experiment in which plants were grown in greenhouses. TF was more absorbent and had less upward attraction than IM. The IM soil was more favorable for Cd precipitation than was the TF soil. Leaching remained the dominant effect, with only 2.28–3.40% and 2.65–3.90% of Cd absorbed by IM and TF, respectively. The present study on the vertical migration of Cd provides new insights into the phytoremediation mechanisms of IM and TF. HIGHLIGHTSVertical migration rate of Cd in soil was calculated.Cd precipitation in IM soil was greater and more excellence than TF soil.TF was more absorbent and had less upward attraction than IM.Leaching remained the dominant effect with only small absorb. Vertical migration rate of Cd in soil was calculated. Cd precipitation in IM soil was greater and more excellence than TF soil. TF was more absorbent and had less upward attraction than IM. Leaching remained the dominant effect with only small absorb.

Additional file 1: Figure S1. (a) SEM of MoSe2-PVP NPs. (b) Histogram of diameter distribution of MoSe2-PVP NPs. Dynamic light scattering and Tyndall photographs of MoSe2-PVP NPs in (c) DMEM, (d) saline, and (e) H2O. Figure S2. (a) The photographs of scavenging ability of MoSe2-PVP NPs for ABTS+. Figure S3. (a) Absorbance of the reaction of H2O2 in the presence of MoSe2-PVP NPs (200 ��g/mL) with time; (b) Kinetic change at 650 nm of POD-like of MoSe2-PVP NPs. (c) Kinetic changes at 340 nm of GPx-like of MoSe2-PVP NPs. Figure S4. The safety of MoSe2-PVP NPs in vitro. (a) Cells viabilities of 266-6 cells after cultured with different concentrations of MoSe2-PVP NPs. (b) The photographs of Live/Dead staining corresponding to (a), b: control, c: 50 ��g/mL, d: 100 ��g/mL. Representative graphics are shown, n = 3 independent experiments. Figure S5. (a-i) Hematological test results of mice after the injection with MoSe2-PVP NPs.

In recent decades, although the research on gait recognition of lower limb exoskeleton robot has been widely developed, there are still limitations in rehabilitation training and clinical practice. The emergence of interactive information fusion technology provides a new research idea for the solution of this problem, and it is also the development trend in the future. In order to better explore the issue, this paper summarizes gait recognition based on interactive information fusion of lower limb exoskeleton robots. This review introduces the current research status, methods, and directions for information acquisition, interaction, fusion, and gait recognition of exoskeleton robots. The content involves the research progress of information acquisition methods, sensor placements, target groups, lower limb sports biomechanics, interactive information fusion, and gait recognition model. Finally, the current challenges, possible solutions, and promising prospects are analysed and discussed, which provides a useful reference resource for the study of interactive information fusion and gait recognition of rehabilitation exoskeleton robots.

The use of biochar as a soil amendment has substantial potential to enhance soil quality and carbon sequestration. However, the responses to the addition of biochar based on soil microbial residues are not well understood, particularly at the aggregate level. Herein, a two-year field experiment investigated the characteristics of distribution of microbial residues in calcareous fluvo-aquic soil aggregates (SA) in Henan Province, China. Four treatments were established as follows: no fertilizer (CK), chemical fertilizer (NPK), biochar (BC), and biochar combined with chemical fertilizer (NPK + BC). The results showed that the effects of particle size substantially impacted the microbial residues with 2–0.25 mm SA having the largest contents of amino sugars and microbial residual carbon (MRC), followed by >2 mm SA. Compared with the CK, the NPK treatment markedly enhanced the levels of glucosamine (GluN), galactosamine (GalN), muramic acid (MurA), total amino sugar (TAS), and MRC in the 2–0.25 mm SA by 26.69%, 24.0%, 23.62%, 25.11%, and 24.82%, respectively. The NPK + BC treatment significantly increased the contents of GluN, GalN, TAS, and MRC in the bulk soil and 0.25–0.053 mm SA compared with the NPK treatment. Bacterial biomass and the activity of N-acetyl-glucosaminidase in the bulk soil and SA markedly and positively affected the content of carbon in the amino sugars and microbial residues. Overall, the 2–0.25 mm SA were microenvironments with the largest accumulation of soil microbial residues, and the combined application of NPK + BC was more effective at increasing the accumulation of microbial residues in the SA, which provides an ideal fertilization strategy to improve the soil microenvironment and enhance soil quality.

Different from the high latitudes (24°N-53°N) of China, the low latitudes (4°N-24°N) present large solar elevation angle and strong solar radiation throughout the year. Radiation differences in all directions are smaller than that in high latitudes, which results in the building envelope optimization (BEO) in high latitudes is not applicable to low latitudes. Therefore, for the low latitudes, this research calculated the energy-saving effect of buildings with different shape parameters and the cooling load of thermal performance of different envelope by numerical simulation. In addition, the corresponding energy-saving indexes for cooling load reduction (CLR) are presented. And the energy saving priority of building envelope is mastered by analyzing the percentage of CLR per unit volume, the roofs have the greatest energy saving potential, followed by exterior walls, sunshade and exterior windows. Furthermore, the recommended insulation thickness for the exterior walls and roofs should be 30–40 mm, and of which the CLR value of per unit external wall area can reach 8.5 W/m2. The west exterior window has greater energy saving potential than other orientations. The effect of east and west sunshade on CLR is much greater than that of south sunshade. The recommended length of the north and south shading should be 500–600 mm, in which the cooling load from shading can be reduced by 95% and 15% respectively. The results can be the basis of the design method of the BEO in low latitudes of China.

The Kalpin fold-and-thrust belt (FTB) was active during the Cenozoic and accommodated crustal shortening between the Tian Shan and Tarim Basin. To constrain the timing of thrusting in the Yimugantawu and Kepingtag thrust sheets from north to south in the central area of the Kalpin FTB, we performed apatite fission track (AFT) and apatite (U-Th)/He (AHe) dating, as well as sandbox experiments. The AFT central ages of the Yimugantawu and Kepingtag thrust sheets range from 93.0 to 148.7 Ma. Single grain AHe ages of the Kepingtag thrust sheet (10.7–27.1 Ma) are younger than those of the Yimugantawu thrust sheet (15.1–82.5 Ma), indicating a southward propagation of the Cenozoic deformation. Combined inverse and forward thermal modeling suggest that the Yimugantawu and Kepingtag thrust sheets underwent initial cooling and deformation at 25–20 Ma and 15–10 Ma, respectively. The sandbox experiments also suggest that the Yimugantawu thrust sheet underwent deformation before the Kepingtag thrust sheet was activated, confirming the sequence revealed by low-T thermochronology. This study provides new insights into the timing of deformation at the northern margin of the Tarim Basin, which can significantly enhance understanding of the tectonic evolution of Central Asia.

BACKGROUND: The combination of wastewater treatment and algal biofuel production has received increasing attention in recent years owing to its many advantages. In order to clarify the influence of different organic pollutants such as carbohydrates, volatile fatty acids (VFAs) and proteins in domestic wastewater on the cultivation of Chlorella vulgaris, three simulated domestic sewages containing glucose, sodium acetate (NaAc) and protein respectively were prepared in this study to culture C. vulgaris in mixotrophic way. RESULTS: The biomass productivities of C. vulgaris cultured in wastewaters containing glucose and NaAc were 63.5 and 55.2 mg L⁻¹ day⁻¹ respectively, which were 2.61‐ and 2.27‐fold larger than that achieved in photoautotrophic condition. Owing to the higher biomass productivity, better performance of nutrient removal was also achieved in wastewater containing glucose or NaAc. Different from glucose and NaAc, protein in the wastewater had no significant effect on C. vulgaris growth and nutrient removal. Chlorella vulgaris cultured in NaAc and glucose wastewaters achieved the highest lipid (17.35 mg L⁻¹ day⁻¹) and carbohydrate (18.75 mg L⁻¹ day⁻¹) productivities respectively, indicating that wastewater containing these two organic substances has certain advantages in microalgal liquid biofuel production. CONCLUSIONS: Organic matters in wastewater have important effects on microalgae growth and the chemical composition of algal cells. Carbohydrates and VFAs in wastewater can significantly promote the growth of C. vulgaris and promote the accumulation of lipid by microalgae. © 2019 Society of Chemical Industry

Additional file 1. 1. Materials. 2. Characterization of IrO2@MSN@PDA-BSA NPs. Fig. S1. (a) The TEM images of IrO2@MSN@PDA-BSA NPs; (b) the corresponding size distributions of IrO2-PVP nanoparticles. Fig. S2. EDS spectra of IrO2@MSN@PDA-BSA NPs. Fig. S3. FTIR spectra of PVP, PDA, and IrO2@MSN@PDA-BSA NPs. Fig. S4. Release of Ce6 from IrO2@MSN@PDA-BSA(Ce6) NPs. Fig. S5. Variation of the dissolved oxygen (DO) content at different pH values (pH 6.0 and 7.4). Fig. S6. Routine blood test of IrO2@MSN@PDA-BSA(Ce6) treated KM mice fed for different days.

Additional file 1: Figure S1. (a) AFM image of LMM@BSA, (b) the height of LMM@BSA. Figure S2. XPS spectra of LMM: (a) Mo 3d, (b) Al 2p, (c) Mg 1s and (d) S 2p. Figure S3. Dynamic light scattering of LMM@BSA nanosheets dispersed in DMEM. Figure S4. (a) Cell viability profiles; (b–f) appearance of calcein-AM/PI dyed L929 cells treated with different concentration of LMM@BSA clay nanosheets (incubation time: 24 h): (b) control; (c) 50 μg/mL; (d) 100 μg/mL; (e) 250 μg/mL; (f) 500 μg/mL. Figure S5. (a, b) The morphology of cell treated with (a) saline and (b) LMM@BSA clay nanosheets (500 μg/mL). Figure S6. Hemolysis percentage of mRBCs co-incubated with LMM@BSA clay nanosheets (concentration: 0–500 μg/mL) for 2 h. Figure S7. UV–vis–NIR spectra of prepared nanosheets. Figure S8. (a) Cell viability profiles; (b–d) appearance of calcein-AM/PI dyed cells after PTT treatments (1 W/cm2) with different concentration of LMM@BSA clay nanosheets: (b) 100 μg/mL; (c) 250 μg/mL; (d) 500 μg/mL. Figure S9. (a) Cell viability profiles after different treatments; (b–g) appearance of calcein-AM/PI stained cells treated with (b) DMEM + saline without laser; (c) DMEM + LMM@BSA without laser; (d–g) DMEM + LMM@BSA with laser of (d) 0.2 W/cm2; (e) 0.5 W/cm2; (f) 0.8 W/cm2; (g) 1.0 W/cm2. Control: 0 2 W/cm2. Figure S10. (a) Cell viability profiles treated with LMM@BSA/Ce6 annd 660 nm laser (0.1 W/cm2) irradiation for different time points; (b–f) appearance of calcein-AM/PI stained cells after PDT treatments with varied irradiated duration: (b) 0 min; (c) 1 min; (d) 2 min; (e) 3 min; (f) 5 min. Figure S11. The routine blood test of mice (a) white blood cell (WBC); (b) red blood cells (RBC); (c) hemoglobin (HGB); (d) hematocrit (HCT); (e) mean corpuscular volume (MCV); (f) mean corpuscular hemoglobin (MCH); (g) mean corpuscular hemoglobin concentration (MCHC); (h) platelet (PLT); and (i) red cell distribution width (RDW) with feeding for varied days. Figure S12. H&E-stained tissue sections of major organs of KM mice that injected with saline or LMM@BSA/Ce6 nanosheets and fed for 1 and 7 days.

Each year there are nearly 57 million deaths around the world, with over 2.7 million in the United States. Timely, accurate and complete death reporting is critical in public health, as institutions and government agencies rely on death reports to analyze vital statistics and to formulate responses to communicable diseases. Inaccurate death reporting may result in potential misdirection of public health policies. Determining the causes of death is, nevertheless, challenging even for experienced physicians. To facilitate physicians in accurately reporting causes of death, we present an advanced AI approach to determine a chronically ordered sequence of clinical conditions that lead to death, based on decedent's last hospital discharge record. The sequence of clinical codes on the death report is named as causal chain of death, coded in the tenth revision of International Statistical Classification of Diseases (ICD-10); in line with the ICD-9-CM Official Guidelines for Coding and Reporting, the priority-ordered clinical conditions on the discharge record are coded in ICD-9. We identify three challenges in proposing the causal chain of death: two versions of coding system in clinical codes, medical domain knowledge conflict, and data interoperability. To overcome the first challenge in this sequence-to-sequence problem, we apply neural machine translation models to generate target sequence. Along with three accuracy metrics, we evaluate the quality of generated sequences with the BLEU (BiLingual Evaluation Understudy) score and achieve 16.04 out of 100. To address the second challenge, we incorporate expert-verified medical domain knowledge as constraint in generating output sequence to exclude infeasible causal chains. Lastly, we demonstrate the usability of our work in a Fast Healthcare Interoperability Resources (FHIR) interface to address the third challenge., 11 pages, 8 figures, 8 tables. Updates: (1) Added Section II: Recent Work (2) Added three accuracy evaluation criteria (3) Re-run experiments of OpenNMT and updated the results and discussion in Section VI: Results and Discussion (4) Finished FHIR mobile app and updated Section VII: FHIR Interface (5) Revised Section VIII: Conclusion accordingly

To increase the adsorption capacity of the Corylus heterophylla Fisch(HS) for Pb2+, HS was chemically modified using NaOH aqueous solution and 95% ethanol and was labeled as SHS; then SHS was chemically modified using mercaptoacetic acid. The SHS modified with mercaptoacetic acid(MHS) was characterized using FTIR, SEM, and XPS. The results indicated that the —SH group was present on MHS, and after Pb2+ adsorption, the absorption value of the characteristic peak of the —SH group decreased. The adsorption and desorption properties of this functionalized material were investigated as well as the influences of parameters, such as pH value, type of desorption reagent, dosage, flow rate and maximum sample volume. The Pb2+ adsorption of MHS reached a maximum with pH>5. The experimental data of Pb2+ adsorption using MHS were fitted using the Langmuir isothermal adsorption model, and a maximum adsorption capacity of 61.54 mg/g was obtained. This was much higher than the adsorption capacity of SHS before modification with the thiol group. After adsorption, MHS was desorbed using a 0.2 mol/L HCl solution, and the percent of desorption was higher than 99%. MHS was used as a solid-phase extractant in the analysis and determination of Pb2+ content in food and water samples, and the enrichment times achieved 150-fold.

Cooling load characteristics play a key role to the building, especially in self-sustained building. It is determined mainly by the building envelope thermal performance. This research investigates the effect of the building envelope on cooling load in low latitude and hot-humid area. In this paper, based on cooling load simulations, the effect of reducing the cooling load of building envelope and the life cycle cost was analyzed. In addition, the energy-saving system was established. For the life cycle cost analysis, the cost of each strategy was obtained through a survey in local stores. This paper determining the effect of external walls, windows, roof, shading on the building cooling load, and pointed out the optimum insulation thickness of roof and all orientation exterior wall. And the optimum window structure and exterior shading length was give.

Deep Learning has thrived on the emergence of biomedical big data. However, medical datasets acquired at different institutions have inherent bias caused by various confounding factors such as operation policies, machine protocols, treatment preference and etc. As the result, models trained on one dataset, regardless of volume, cannot be confidently utilized for the others. In this study, we investigated model robustness to dataset bias using three large-scale Chest X-ray datasets: first, we assessed the dataset bias using vanilla training baseline; second, we proposed a novel multi-source domain generalization model by (a) designing a new bias-regularized loss function; and (b) synthesizing new data for domain augmentation. We showed that our model significantly outperformed the baseline and other approaches on data from unseen domain in terms of accuracy and various bias measures, without retraining or finetuning. Our method is generally applicable to other biomedical data, providing new algorithms for training models robust to bias for big data analysis and applications. Demo training code is publicly available., 9 pages, 5 figures

Table S1. Strains and plasmids used in this study. Table S2. Primers used in this study. Table S3. Putative target genes of SACE_5754 were screened by EMSAs. Figure S1. Analyses of SACE_5754 homologs and comparison of growth rates and morphological differentiation in S. erythraea A226 and relevant strains. Figure S2. Inactivation of SACE_0388 in S. erythraea A226. Figure S3. Inactivation of SACE_3599 in S. erythraea A226. Figure S4. Inactivation of SACE_6149 in S. erythraea A226. Figure S5. Effects of SACE_5754 disruption on transcriptional levels of related genes involving in TCA cycle. Figure S6. Possible regulatory pathway of SACE_5754 on erythromycin biosynthesis in S. erythraea. Figure S7. qRT-PCR analysis of the accuracy of transcriptome analysis. (DOCX 968 kb)

Packs with high self-discharge accelerate the capacity decline and even cause the safe issues. It is important to keep the self-discharge rate at a uniform and small level for all the cells in a pack. The traditional clustering methods are either costly or time-consuming. In this paper, a novel classification method is invented to realize the fast estimation of the relative self-discharge rate. Firstly, the balancing technology for large-scale cells is proposed to ensure the voltage equalization. Small batches of equalized cells are then clamped in detection circuits to realize the external mapping of the internal current originated from the self-discharge. The relative self-discharge rates of the cells are estimated by the equivalent parallel circuit model with self-discharge. The results show that the method can detect the cell with a relative self-discharge rate of 3%/month for three cells at a time within 1 h. To further classify the cells according to the relative self-discharge rate, microammeters are connected in each branch of the detection circuits. The results show that the method can identify the relative self-discharge rate in less than 2 h, and the errors can be kept within 0.1%/month.

Apatite fission-track (AFT) analysis, a widely used low-temperature thermochronology method, can provide details of the hydrocarbon generation history of source rocks for use in hydrocarbon exploration. The AFT method is based on the annealing behavior of fission tracks generated by 238U fission in apatite particles during geological history. Due to the cumbersome experimental steps and high expense, it is imperative to find an efficient and inexpensive technique to determinate the annealing degree of AFT. In this study, on the basis of the ellipsoid configuration of tracks, the track volume fraction model (TVFM) is established and the fission-track volume index is proposed. Furthermore, terahertz time domain spectroscopy (THz-TDS) is used for the first time to identify the variation of the AFT annealing degree of Durango apatite particles heated at 20, 275, 300, 325, 450, and 500 ℃ for 10 h. The THz absorbance of the sample increases with the degree of annealing. In addition, the THz absorption index is exponentially related to annealing temperature and can be used to characterize the fission-track volume index. Terahertz time domain spectroscopy can be an ancillary technique for AFT thermochronological research. More work is urgently needed to extrapolate experimental data to geological conditions.

This study investigated the effect of co-incorporation of two different kinds of nano materials with different forms, layers (Na-MMT) and mesoporous silica particles (MCM-41), into the polymer matrix on the corrosion performance of epoxy resin. Correspondingly corrosion performance of the coatings was studied by electrochemical impedance spectroscopy (EIS) in 3.5% NaCl aqueous solution and salt spray test. The X-ray diffraction (XRD) measurement showed that the Na-MMT layers were exfoliated and the hexagonal framework structure of MCM-41 was retained during and after the composite preparation. The co-incorporation of Na-montmorillonite (Na-MMT) and MCM-41 into the epoxy coating possessed the best corrosion resistance than incorporating either Na-MMT or MCM-41 particles separately due to different interfacial structures between the fillers and the matrix.

Understanding the geological units of a reservoir is essential to the development and management of the resource. In this paper, drill cuttings from several depths from an oilfield were studied using terahertz time domain spectroscopy (THz-TDS). Cluster analysis (CA) and principal component analysis (PCA) were employed to classify and analyze the cuttings. The cuttings were clearly classified based on CA and PCA methods, and the results were in agreement with the lithology. Moreover, calcite and dolomite have stronger absorption of a THz pulse than any other minerals, based on an analysis of the PC1 scores. Quantitative analyses of minor minerals were also realized by building a series of linear and non-linear models between contents and PC2 scores. The results prove THz technology to be a promising means for determining reservoir lithology as well as other properties, which will be a significant supplementary method in oil fields.

For remediation of trichloroethylene (TCE) contaminated groundwater, activated carbon (AC) has been used to adsorb and reduce the TCE concentration and to manage contaminant migration. Additionally, AC may also act as an activator of the electron-transfer mediator in activating persulfate anion (S2O82−) to generate sulfate radical (SO4−·) for contaminant destruction. The objective of the present research was to examine the combined use of AC and persulfate to treat TCE. The degradation of persulfate in the presence of AC follows a first-order kinetic behavior, and the faster persulfate degradation is observed when elevated AC dosage is used. Higher initial persulfate concentration results in a decrease of the persulfate degradation rate. Upon persulfate oxidation, the AC surface properties are altered including: an increase in acidity of surface concentration, a decrease in pHzpc, and a slight decrease in the surface area. The results of a study of adsorption kinetics and isotherms suggest that the adsorp...

Objective: To explore the effects of Yizhi Capsule (YZC) on learning and memory disorder and β-amyloid peptide induced neurotoxicity in rats.Methods: Various doses of YZC were administered to Sprague-Dawley (SD) rats for 8 consecutive days, twice a day. On the 8th day of the experiment, scopolamine hydrobromide was intraperitoneally injected to every rat and Morris water maze test and shuttle dark avoidance test were carried out respectively to explore the changes of learning and memory capacities in the rats. Besides, after the cerebral cortical neurons of newborn SD rats aged within 3 days were culturedin vitro for 7 days, drug serum containing YZC was added to the cultured neurons before or after β amyloid peptide25–35 (Aβ25–35) intoxication to observe the protective effect of YZC on neurotoxicity by MTT assay and to determine the LDH content in the supernatant.Results: Compared with those untreated with YZC, the rats having received YZC treatment got superiority in shorter time of platform seeking in Morris water maze test, as well as elongated latent period and less times of error in shuttle dark avoidance test. On the cultured neurons, YZC drug serum could effectively increase the survival rate of Aβ25–35 intoxicated neurons and reduce the LDH contents in cultured supernatant.Conclusion: YZC has an action of improving learning and memory disorder, and good protective effect on Aβ25–35 induced neurotoxicity in SD rats.

Balance equation approach to the hot-electron transport in electric and magnetic fields is reformulated. The balance equations are re-derived from the Boltzmann equation. A new expression for the distribution function is reported in the present paper. It is homogeneous steady solution of the Boltzmann equation in constant relaxation time approximation. It holds when or . As an example, the mobility of 2D electron gas in the GaAs-AlGaAs heterojunction is computed as a function of electric field and magnetic field.

A theory of the c-axis infrared conductivity of a dx2-y2-wave superconductor due to the competition between the interlayer direct hopping and the hopping assisted by the spin fluctuations has been developed. The prediction of our theory captures the main feature of the experiment. Thus we argue that the anomalous behavior of the c-axis infrared conductivity of the underdoped cuprates in superconducting state may be properly understood within the theory.

The influence of pseudogap on the inelastic neutron scattering spectra of the underdoped lanthanum cuprate is studied on the basis of the model which incorporates both the superconducting state and pseudogap state. It is found that the striking effects of the influence of the pseudogap on the incommensurability of the spin excitation spectrum are that in the superconducting state the pseudogap makes the intensity of the incommensurate peak increase, in the normal state the pseudogap not only makes the intensity of the incommensurate peak increase, but also sharpens the incommensurate peak and increases incommensurability.

A mean field SDW analysis of pseudogap in the underdoped cuprates is proposed on the basis of the $t-t^{\prime}-U$ Hubbard model. The prediction of our theory is consistent with the experiment quite well within the uncertainty of the present experimental measurement. Therefore we argue that the pseudogap phenomenon in the underdoped cuprates can be well explained within the mean field approximation., RevTex 19 Pages, 8 Eps figures; The paper (cond-mat/9912481) is revised, Manuscript rewitten, figures revised

The mobility of a two-dimensional electron gas in GaAs-AlGaAs heterojunction is recomputed through solving numerically the balance equation. The peculiarity of the present study lies in that a new expression for the distribution function and the renormalized phonon frequency are used in the computation. Compared with those reported by previous authors, our result shows better agreement with the experimental data.

Nowadays, information disclosure is a noticeable topic to both practice and academy since it has significant effect on corporate governance and capital market operation. Open and transparent information disclosure can reduce the information asymmetry between insiders and outsiders. The main purpose of this study is to construct an information transparency evaluation model. In this paper, we used the information disclosure record obtained from the website of the Shenzhen Stock Exchange (SSE) as the level of listed companies information transparency and employed the support vector machine technique for building classification model. Experimental results demonstrate that the SVM has better performance than other methods and it is a considerable approach for information transparency research.

The magnetic contribution to the thermal expansion of Cu-O layer in YBa2Cu3O7-δ is studied with the nearly antiferromagnetic Fermi liquid model. Our analysis suggests that this additional thermal expansion due to antiferromagnetic spin fluctuation is the origin of the Cu-O plane buckling.

The objective of this study was to demonstrate the regeneration of trichloroethylene (TCE) spent activated carbon using persulfate oxidation and iron activated persulfate (IAP) oxidation. Both processes resulted in decreases in the adsorbability of regenerated activated carbons. IAP was shown to rapidly degrade the aqueous TCE and causes a significant mineralization of the TCE. The release of chloride ions provided evidence of this. Persulfate oxidation mainly resulted in desorption of TCE from the activated carbon and only partial mineralization of the TCE through a carbon activated persulfate reaction mechanism. Concerning destruction of the TCE, in the regeneration test using persulfate, 30% of the original TCE was present in the solution and 9% remained on the activated carbon after the first regeneration cycle. In contrast, in the test that used IAP, it was observed that no TCE was present in the solution and only approximately 5% of the original TCE remained on the activated carbon after the first regeneration. Following the regeneration cycles, elemental analysis was carried out on the samples. BET surface area and EDS analysis showed some effects on the physico-chemical properties of the activated carbon such as a slight decrease in the surface area and the presence of iron precipitates on the carbon.

To identify the influence of tumor characteristics on the outcome of liver transplantation (LT) among patients with hepatocellular carcinoma (HCC).A retrospective analysis was performed on 251 consecutive patients with HCC who underwent LT between April 2001 and February 2006 at our institution. We compared the outcome of the patients classified by different tumor related factors. Survival analysis was performed using Kaplan-Meier and Cox proportional hazards regression methods.Macroscopic vascular invasion, lymph node metastasis, Edmondson pathologic classification, microscopic tumor thrombosis, tumor location, satellite nodules and alpha-fetal protein (AFP) all significantly affected the overall survival and/or recurrence-free survival post-LT (P0.01 or P0.05). Pre-operative treatment and hepatitis background had no effect to the prognosis (P0.05). At multivariate Cox regression analysis, the factors associated with mortality or recurrence were macroscopic vascular invasion, microscopic tumor thrombosis and satellite nodules (P0.01 or P0.05).Edmondson grade III - IV, microscopic tumor thrombosis, left lobar or bilobar tumor, satellite nodules and AFPor = 300 microg/L were predictive factors of poor prognosis. Presence of macroscopic vascular invasion or lymph node metastasis should be contraindicated.

To present a new neurovascular island flap for fingertip reconstruction.Based on the transverse palmar branch of the digital artery, this flap was designed on the volar side of a digit and reversed to repair the fingertip defects.12 fingers in 11 patients were reconstructed using this flap. Of them, 11 flaps survived and one necrosed. The contour of the reconstructed fingers looked well.This new neurovascular island flap provides excellent padding and sensation for fingertip reconstruction. The technique is simple.

Objective: To investigate the effects of Capsule Yi-Zhi (CYZ is extracted and purified by our department mainly from Polygonum Multiflorum, Ginseng and Korean Epimedium herb, among which quantitatively effective ingredients are more than 50%.) on learning and memory disorder and â-amyloid protein induced neurotoxicity in rats. Methods: Various doses of CYZ were administered to Sprague-Dawley (SD) rats for 8 days, twice a day. Then scopolamine hydrobromide (Sco) intraperitoneal injection was performed on each rat and the Morris water maze test and step-though test were carried out respectively to explore the changes of the rats’ learning and memory capacities. Primary rat cortex neurons were cultured in vitro for 7 days and then, serum containing CYZ was added to neurons before or after the addition of â Amyloid peptide25–35 (Aâ25–35) to see the extent of CYZ’s protectiveness on neurotoxicity. MTT assay and test of level of LDH in the culture media were performed to achieve this aim. Results Compared with control group, rats in Morris water maze test required significantly decreased time in finding the platform under the water surface from 19.5 ± 11.40 to 8.5 ± 2.39, 8.8 ± 3.07, and 7.4 ± 3.87 sec, respectively, and in step-though test, the latent period rose from 22.70 ± 23.07 to 148.50 ± 124.02, 176.50 ± 143.36, and 196.60 ± 128.00 sec and the error number decreased from 14.20 ± 7.74 to 7.50 ± 8.02, 3.40 ± 4.43 and 2.50 ± 3.10 respectively, all with statistical significance. Moreover, in cultured primary neurons, the dramatic drop of LDH level in culture media from 3670.2 ± 437.65 to 864.5 ± 371.69 and 1444 ± 635.18 U L and the high A scores rising from 0.68 ± 0.193 to 0.93 ± 0.009 and 0.96 ± 0.239 in MTT test indicated that CYZ could effectively resist the neurotoxicity induced by Aâ25–35. Conclusions: CYZ presented promising effects on learning and memory dysfunction and Aâ induced neurotoxicity in vitro.

In the present letter, we study the magnetic contribution to the thermal expansion of Cu−O layer in YBa2Cu3O7−δ with the nearly antiferromagnetic Fermi liquid model. Our analysis suggest that this additional thermal expansion due to antiferromagnetic spin fluctuation is the origin of the Cu−O plane buckling.

So far, the theories of the cuprate pseudogap may be broadly divided into two main schools of though. One is based upon the idea that view the pseudogap as deriving from some of precursor superconductivity. Another assumes that associate the pseudogap phenomena with magnetic pairing of some sort. Both the scenario of superconducting fluctuation and the scenario of magnetic pairing of some sort on the pseudogap in underdoped cuprate are based upon the idea that a fluctuation of a certain type exists at temperatures higher than the usual superconducting transition temperature and has an effect on the single particl self-energy and just such a self-energy leads to the gap-like structure of the spectral weight. In this paper we argue that although a fluctuation of a certain type has an effect on the origin of the pseudogap, it is not the crucial factor of the origin of the pseudogap in underdoped cuprate. We analysis the scenario of the pseudogap in the underdoped cuprate based on the model that can bring about the spin density wave (SDW) and find the new dispersion characteristics of the high temperature cuprate superconductors (excepting two different saddle points located at ($\pm\pi$, 0) and (0, $\pm\pi$)) and suggest that the pseudogap formation might been due to the unique interior of the underdoped cuprate., Comment: plain tex, 12 pages, 8 figures