The Performance Investigation of Smart Diagnosis for Bearings Using Mixed Chaotic Features with Fractional Order.

This article presents a performance investigation of a fault detection approach for bearings using different chaotic features with fractional order, where the five different chaotic features and three combinations are clearly described, and the detection achievement is organized. In the architecture of the method, a fractional order chaotic system is first applied to produce a chaotic map of the original vibration signal in the chaotic domain, where small changes in the signal with different bearing statuses might be present; then, a 3D feature map can be obtained. Second, five different features, combination methods, and corresponding extraction functions are introduced. In the third action, the correlation functions of extension theory used to construct the classical domain and joint fields are applied to further define the ranges belonging to different bearing statuses. Finally, testing data are fed into the detection system to verify the performance. The experimental results show that the proposed different chaotic features perform well in the detection of bearings with 7 and 21 mil diameters, and an average accuracy rate of 94.4% was achieved in all cases.

[Aerobic Granulation Stability and Microbial Diversity of Filamentous Bulking Sludge].

Filamentous bacteria, as one of the common bacteria types in wastewater biological treatment, are considered to be the main factor to induce sludge bulking. However, because of its special filamentous shape, it plays a crucial role in the formation of sludge particles. Taking filamentous bulking sludge as the research object, the effect of filamentous bacteria on the sludge granulation process and maintaining the stability of sludge granules was studied, and the microbial diversity of the sludge system was analyzed. Filamentous bulking sludge (SVI=241.56 mL·g-1) and flocculated sludge (SVI=64.22 mL·g-1) were respectively inoculated to carry out granulation culture. The results showed that the time of particle appearance of bulking sludge and flocculated sludge was 20 days and 40 days, respectively; the mature particle sizes were 650 µm and 700 µm, respectively; and the granulation time of bulking sludge was only half that of flocculated sludge. After adding the anoxic zone, the granules were broken to differing degrees, but the SV30/SV5 value of mature granules recovered to 1 after short-term fluctuation, and the stability of the mature granules was stronger. The analysis of microbial community structure showed that the relative abundance of norank_o__Saccharimonadales, unclassified_o__Saccharimonadales, and unclassified_f__Saccharimonadaceae increased from 0.05%, 0.01%, and 0.01% to 4.09%, 3.15%, and 1.12%. The existence and accumulations of these hydrophobic bacteria were important for rapid granulation. The removal rates of COD, NH4+-N, and TN were 94%, 99%, and 35% and 92%, 97%, and 30%, respectively, in SBR1 of bulking sludge and SBR2 of flocculated sludge, and the removal rates of TP were 60% and 30%, respectively.

Comparative study of two cephalosporin antibiotics binding to calf thymus DNA by multispectroscopy, electrochemistry, and molecular docking.

The over-use of antibiotics has caused a number of problems such as contamination of antibiotic residues and virus resistance, and therefore has attracted global attention. In this study, spectroscopic techniques and molecular docking were employed to predict conformational changes and binding interaction between two cephalosporins (cefaclor and cefixime) and calf thymus DNA (ctDNA). Fluorescence and UV-vis spectra suggested that static quenching was predominant and cephalosporin bound to the groove region of ctDNA. Binding parameters calculated by the Stern-Volmer and Scatchard equations showed that cephalosporin bound to ctDNA with a binding affinity in the order of 103  L mol-1 . Thermodynamic parameters further indicated that the reaction was a spontaneous process driven by enthalpy and entropy, and that the main binding force was an electrostatic force. The effects of iodide, denaturant, thermal denaturation and pH on a cephalosporin-Hoechst-DNA complex were also studied, and the results confirmed that cephalosporin bound to the groove area of DNA. Finally, these results were further confirmed by molecular docking and electrochemical studies.

Probing the interaction of cephalosporin with bovine serum albumin: A structural and comparative perspective.

Cephalosporins belong the largest class of antibiotics used in the treatment of a wide range of infectious diseases caused by susceptible organisms. In the present study, we chose two typical antibiotics cefalexin/cefixime based on their structure, and investigated the interaction of cephalexin/cefixime with bovine serum albumin (BSA) using UV-vis absorption spectra, fluorescence spectroscopy, circular dichroism (CD) spectroscopy and molecular modeling approaches. Spectroscopic experiments revealed the formation of a BSA - cefalexin/cefixime complex. The binding parameters calculated using a modified Stern - Volmer method and the Scatchard method reached 103 -104  L·mol-1 . Thermodynamic parameter studies revealed that binding characteristics by negative enthalpy and positive entropy changes, and electrostatic interactions play a major role. Site marker competitive displacement experiments and molecular modeling approaches demonstrated that cefalexin and cefixime bind with appropriate affinity to site I (subdomain IIA) of BSA. Furthermore, synchronous fluorescence spectra, CD spectra and molecular modeling results indicated that the secondary structure of BSA was changed in the presence of cefalexin and cefixime. Additionally, the effects of metal ions on the BSA - cefalexin/cefixime system were also assessed.

Insights into the interaction of methotrexate and human serum albumin: A spectroscopic and molecular modeling approach.

In this study, fluorescence spectroscopy and molecular modeling approaches were employed to investigate the binding of methotrexate to human serum albumin (HSA) under physiological conditions. From the mechanism, it was demonstrated that fluorescence quenching of HSA by methotrexate results from the formation of a methotrexate/HSA complex. Binding parameters calculated using the Stern-Volmer method and the Scatchard method showed that methotrexate binds to HSA with binding affinities in the order 104  L·mol-1 . Thermodynamic parameter studies revealed that the binding reaction is spontaneous, and that hydrogen bonds and van der Waals interactions play a major role in the reaction. Site marker competitive displacement experiments and a molecular modeling approach demonstrated that methotrexate binds with appropriate affinity to site I (subdomain IIA) of HSA. Furthermore, we discuss some factors that influence methotrexate binding to HSA.

Novel rare earth tungstoarsenate heteropolyoxometalates K11[Ln(AsW 11O 39) 2]·xH 2O (Ln = La, Nd, Sm) binding to bovine serum albumin: spectroscopic approach.

The rare earth salts of heteropoly have been widely applied in many fields. In this study, the biological activity of rare earth tungstoarsenate heteropolyoxometalates K11[Ln(AsW11O39)2]·xH2O (abbr. LnW11, Ln = La (x = 24), Nd (x = 17), and Sm (x = 19)) were investigated by spectroscopic methods including fluorescence spectroscopy and UV-vis absorption spectroscopy at different temperatures. In the mechanism discussion, it was proved that the fluorescence quenching of bovine serum albumin (BSA) by LnW11 is initiated by complex formation. The thermodynamic parameters suggested that the binding of LnW11 to BSA is spontaneous, and the mainly force is electrostatic interactions. Site marker competitive experiments demonstrated that LaW11 binds with high affinity to site I (subdomain IIA) of BSA; but SmW11 and NdW11 bind with affinity to both site I (subdomain IIA) and site II (subdomain IIIA) of BSA. The results of synchronous fluorescence spectrum indicate that the secondary structure of BSA molecules was changed in the presence of LnW11. In addition, the binding parameters, binding site number, and effect of metal ions on LnW11-BSA were also discussed.

Preparation and in vitro evaluation of pDNA-CaPi-PLGA nanoparticles with a core-shell structure / 药学学报

To develop a core-shell structure pDNA-CaPi-PLGA nanoparticles (CS-pDNA-CaPi-PLGA-NPs), calcium phosphate-pDNA nano complexes (CaPi-pDNA) were encapsulated inside of PLGA shells. The characteristics of the nanoparticles, including morphology, average particle size, zeta potential, entrapment efficiency, loading efficiency, stability in medium, pDNA protection ability from nuclease degradation, in vitro release, cytotoxicity and cell transfection were investigated and compared with the embedded structured CaPi modified PLGA nanoparticles (embedded-pDNA-CaPi-PLGA-NPs). The results showed that the obtained CS-pDNA-CaPi-PLGA-NPs were spherical in shape with an average particle size of (155 +/- 4.5) nm, zeta potentials of (-0.38 +/- 0.1) mV, entrapment efficiency of (80.56 +/- 2.5)% and loading efficiency of (1.16 +/- 0.04)%. The CS-pDNA-CaPi-PLGA-NPs were stable in the release media and could protect pDNA against nuclease degradation. And they also exhibited sustained release of pDNA in vitro. The highest gene transfection efficiency of the CS-pDNA-CaPi-PLGA-NPs in vitro reached (24.66 +/- 0.46)% (after 72 h transfection), which was significantly higher than that of free pDNA [(0.33 +/- 0.04)%, P < 0.01] and the pDNA-PLGA-NPs [(1.5 +/- 0.07)%, P < 0.01]. Besides, the transfection lasted for longer time than that of embedded-pDNA-CaPi-PLGA-NPs and the cytotoxicity of it was significantly lower than that of PEI (P < 0.01). These results indicate that CS-pDNA-CaPi-PLGA-NPs are a promising non-viral gene vector. Key words: gene delivery system; polylactic-co-glycolic acid; calcium phosphate; nanoparticle

[Preliminary experiences of application of sentinel lymph node navigation technique in early gastric cancer].

OBJECTIVE: To investigate the feasibility and clinical significance of sentinel lymph node (SLN) navigation limited surgery in early gastric cancer (EGC). METHODS: Thirty-nine patients confirmed with EGC between January 2002 and December 2006 were randomly divided into tailored surgery group (20 cases) and conventional surgery group (19 cases). By combining the mapping agents of (99m)Tc labeled sulfur colloid solution and blue violet, SLN biopsy was conducted in tailored surgery group, in which a limited gastric resection with D0-D1 lymphadenectomy was performed in 17 cases with negative SLN examined by routine HE staining during operation; standard radical gastrectomy with lymphadenectomy (D2) was conducted in the other 3 cases with positive SLN and in all the cases of conventional surgery group. The diagnostic accuracy and false-negative rate of SLN status were calculated respectively. The operation outcome and postoperative complication and survival rate were compared between the two groups. RESULTS: SLNs were detected in all 20 patients with a successful detection rate of 100% in tailored surgery group. The number of detected SLNs ranged from 1 to 3, with a mean of 2.2 per case. The diagnostic accuracy and false-negative rate was 95% and 5%, respectively. The hospital stay and recovery time of gastrointestinal functions in patients undergoing limited surgery were significantly shorter than in conventional surgery group and with similar postoperative survival and less complications. CONCLUSIONS: SLN biopsy may provide an accurate diagnostic procedure for detecting lymph node metastasis in EGC. Patients with node-negative EGC receiving limited surgery are likely to benefit from minimally invasive approach with the similar survival as standard radical surgery.

[Clinical significance of sentinel lymph node detection by combining the dye-directed and radioguided methods in gastric cancer].

OBJECTIVE: To investigate the feasibility and accuracy of detection of sentinel lymph nodes (SLN) with combining the dye-directed and radioguided methods in gastric cancer and assess its potential role in determining the rational extent of lymphadenectomy in gastric cancer surgery. METHODS: Twenty-six patients of gastric cancer diagnosed as T(1)-T(3) were enrolled in this study. Endoscopic injection submucosally of (99m)Tc labeled sulfur colloid solution was performed around the primary tumor 2 - 4 h before operation. Immediately after laparotomy, patent blue violet was injected into subserosal layer adjacent to the tumor. SLNs were defined as blue stained nodes or(and) those containing 10 times more radioactivity than surrounding tissue with a gamma probe. Standard radical gastrectomy with lymphadenectomy (D(2) or D(3)) was performed in most of the patients, however, limited surgery was performed in early gastric cancer (EGC) when a rapid frozen examination indicated negative SLNs. All resected nodes were examined postoperatively by routine HE stain and those negative SLNs were examined with further cytokeratin immunohistochemistical staining. The diagnostic accuracy, sensitivity, negative predictive value and false-negative rate of regional lymph node status on the basis of SLN status were calculated respectively. RESULTS: SLNs were dectected in 25 of 26 patients with a successful detection rate of 96%. The number of SLNs ranged from 1 to 6, with a mean value of 3.2 per case. The SLNs of gastric cancer were only found in N(1) area in 50% of the cases, and only in N(2) or N(3) in 12%. The incidence of metastasis was significantly higher in SLNs than in non-SLNs (35% vs 7%). The diagnostic accuracy, sensitivity, negative predictive value and false-negative rate were 96%, 94%, 7/8 and 6% respectively. Complete analysis of SLN upstaged 2/7 of patients of gastric cancer. CONCLUSIONS: The SLN concept is validated in gastric cancer. Combined-agent SLN mapping is an accurate diagnostic procedure for detecting lymph node metastasis in patients with gastric cancer and may indicate rational extent of lymphadenectomy for gastric cancer.

Sentinel lymph node concept in gastric cancer with solitary lymph node metastasis.

AIM: To study the localization of the solitary metastases in relation to the primary gastric cancers and the feasibility of sentinel lymph node (SLN) concept in gastric cancer. METHODS: Eighty-six patients with gastric cancer, who had only one lymph node involved, were regarded retrospectively as patients with a possible sentinel node metastasis, and the distribution of these nodes were assessed. Thirteen cases with jumping metastases were further studied and followed up. RESULTS: The single nodal metastasis was found in the nearest perigastric nodal area in 65.1% (56/86) of the cases and in 19.8% (17/86) of the cases in a fairly remote perigastric area. Out of 19 middle-third gastric cancers, 3 tumors at the lesser or greater curvatures had transverse metastases. There were also 15.1% (13/86) of patients with a jumping metastasis to N2-N3 nodes without N1 involved. Among them, the depth of invasion was mucosal (M) in 1 patient, submucosal (SM) in 2, proper-muscular (MP) in 4, subserosal (SS) in 5, and serosa-exposed (SE) in 1. Five of these patients died of gastric cancer recurrence at the time of this report within 3 years after surgery. CONCLUSION: These results suggest that nodal metastases occur in a random and multidirectional process in gastric cancer and that not every first metastatic node is located in the perigastric region near the primary tumor. The rate of "jumping metastasis" in gastric cancer is much higher than expected, which suggests that the blind examination of the nodal area close to the primary tumor can not be a reliable method to detect the SLN and that a extended lymph node dissection (ELND) should be performed if the preoperative examination indicates submucosal invasion.