Nonlinear Transition from Mitigation to Suppression of the Edge Localized Mode with Resonant Magnetic Perturbations in the EAST Tokamak

Evidence of a nonlinear transition from mitigation to suppression of the edge localized mode (ELM) by using resonant magnetic perturbations (RMPs) in the EAST tokamak is presented. This is the first demonstration of ELM suppression with RMPs in slowly rotating plasmas with dominant radio-frequency wave heating. Changes of edge magnetic topology after the transition are indicated by a gradual phase shift in the plasma response field from a linear magneto hydro dynamics modeling result to a vacuum one and a sudden increase of three-dimensional particle flux to the divertor. The transition threshold depends on the spectrum of RMPs and plasma rotation as well as perturbation amplitude. This means that edge topological changes resulting from nonlinear plasma response plays a key role in the suppression of ELM with RMPs.

Optimization algorithm based characterization scheme for tunable semiconductor lasers

In this paper, an optimization algorithm based characterization scheme for tunable semiconductor lasers is proposed and demonstrated. In the process of optimization, the ratio between the power of the desired frequency and the power except of the desired frequency is used as the figure of merit, which approximately represents the side-mode suppression ratio. In practice, we use tunable optical band-pass and band-stop filters to obtain the power of the desired frequency and the power except of the desired frequency separately. With the assistance of optimization algorithms, such as the particle swarm optimization (PSO) algorithm, we can get stable operation conditions for tunable lasers at designated frequencies directly and efficiently.

Study on CH(4) and N(2)O emissions from water-saving irrigation in Phaeozem paddy fields in cold areas

Increasing greenhouse gas emissions and water shortage are two main problems associated with cultivation of rice. Soil moisture control is not only a core technology in water-saving irrigation, but also a decisive factor of greenhouse gas emissions. The CH(4) and N(2)0 emission fluxes from intermittent irrigation and flooding irrigation in Phaeozem paddy fields in cold area were measured in-situ to provide a theoretical basis for studying the regulation of CH(4) and N(2)O emissions and comprehensive assessing the effect of intermittent irrigation on the environment and control of greenhouse gas emissions. During the rice growing period, CH(4) emissions peaked at the tillering stage, whilst N(2)0 emissions peaked twice at the tillering and milky ripening stages. The accumulated emission of N(2)O from the implementation of flooding irrigation in paddy fields was 6.46 gm(-2), whilst that from intermittent irrigation was 5.47 gm(-2). The accumulated emission of N(2)0 from the implementation of flooding irrigation in paddy fields was 36.88 mgm(-2), whilst that from intermittent irrigation was 68.47 mgm(-2). The global warming potential of CH(4) and N(2)0 was 1362.7lkgCO(2)ha(-1) from intermittent irrigation in paddy fields, a value 108.12 kgCO(2)ha(-1) lower than that from flooding irrigation. Intermittent irrigation can thus be used to effectively decrease and control the combined greenhouse effect of CH4 and N20 emissions from rice paddy fields.

Can electrocoagulation process be an appropriate technology for phosphorus removal from municipal wastewater?

This paper evaluated a novel pilot scale electrocoagulation (EC) system for improving total phosphorus (TP) removal from municipal wastewater. This EC system was operated in continuous and batch operating mode under differing conditions (e.g. flow rate, initial concentration, electrolysis time, conductivity, voltage) to evaluate correlative phosphorus and electrical energy consumption. The results demonstrated that the EC system could effectively remove phosphorus to meet current stringent discharge standards of less than 0.2mg/L within 2 to 5min. This target was achieved in all ranges of initial TP concentrations studied. It was also found that an increase in conductivity of solution, voltages, or electrolysis time, correlated with improved TP removal efficiency and reduced specific energy consumption. Based on these results, some key economic considerations, such as operating costs, cost-effectiveness, product manufacturing feasibility, facility design and retrofitting, and program implementation are also discussed. This EC process can conclusively be highly efficient in a relatively simple, easily managed, and cost-effective for wastewater treatment system.

Tumorigenicity analysis of heterogeneous dental stem cells and its self-modification for chromosome instability

Heterogeneity demonstrates that stem cells are constituted by several sub-clones in various differentiation states. The heterogeneous state is maintained by cross-talk among sub-clones, thereby ensuring stem cell adaption. In this study, we investigated the roles of heterogeneity on genetic stability. Three sub-clones (DF2, DF8 and DF18) were isolated from heterogeneous dental stem cells (DSCs), and were proved to be chromosome instability (CIN) after long term expansion. Cell apoptosis were not detected in sub-clones, which exhibited strong tumorigenesis tendency, coupled with weak expression of p53 and aberrant ultra-structure. However, 3 sub-clones did not overexpress tumor related markers or induce tumorigenesis in vivo. The mixed-culture study suggested that 3-clone-mixed culturing cells (DF1) presented apparent decrease in the ratio of aneuploidy. The screening experiment further proved that 3 sub-clones functioned separately in this modification procedure but only mixed culturing all 3 sub-clones, simulated heterogeneous microenvironment, could achieve complete modification. Additionally, osteogenesis capability of 3 sub-clones was partially influenced by CIN while DSCs still kept stronger osteogenesis than sub-clones. These results suggested aberrant sub-clones isolated from heterogeneous DSCs were not tumorigenesis and could modify CIN by cross-talk among themselves, indicating that the heterogeneity played a key role in maintaining genetic stability and differentiation capability in dental stem cells.

Gp130-mediated STAT3 activation by S-propargyl-cysteine, an endogenous hydrogen sulfide initiator, prevents doxorubicin-induced cardiotoxicity

Doxorubicin (Dox) could trigger a large amount of apoptotic cells in the myocardium, which leads to dilated cardiomyopathy and heart failure. S-propargyl-cysteine (SPRC), a producing agent of endogenous hydrogen sulfide (H2S), possesses cardioprotective efficacy. However, the specific effect and mechanism of SPRC in Dox-induced cardiotoxicity remain elusive. Given gp130 with its main downstream signaling molecule, signal transducer and activator of transcription 3 (STAT3), is involved in cardiac myocyte survival and growth; the present study was performed to elucidate whether SPRC counteracts Dox-induced cardiotoxicity, and if so, whether the gp130/STAT3 pathway is involved in this cardioprotective activity. SPRC stimulated the activation of STAT3 via gp130-mediated transduction tunnel in vitro and in vivo. In Dox-stimulated cardiotoxicity, SPRC enhanced cell viability, restored expression of gp130/STAT3-regulated downstream genes, inhibited apoptosis and oxidative stress, and antagonized mitochondrial dysfunction and intracellular Ca(2+) overload. Intriguingly, blockade of gp130/STAT3 signaling abrogated all these beneficial capacities of SPRC. Our findings present the first piece of evidence for the therapeutic properties of SPRC in alleviating Dox cardiotoxicity, which could be attributed to the activation of gp130-mediated STAT3 signaling. This will offer a novel molecular basis and therapeutic strategy of H2S donor for the treatment of heart failure.

Investigate the Metabolic Reprogramming of Saccharomyces cerevisiae for Enhanced Resistance to Mixed Fermentation Inhibitors via 13C Metabolic Flux Analysis

The fermentation inhibitors from the pretreatment of lignocellulosic materials, e.g., acetic acid and furfural, are notorious due to their negative effects on the cell growth and chemical production. However, the metabolic reprogramming of the cells under these stress conditions, especially metabolic response for resistance to mixed inhibitors, has not been systematically investigated and remains mysterious. Therefore, in this study, 13C metabolic flux analysis (13C-MFA), a powerful tool to elucidate the intracellular carbon flux distributions, has been applied to two Saccharomyces cerevisiae strains with different tolerances to the inhibitors under acetic acid, furfural, and mixed (i.e., acetic acid and furfural) stress conditions to unravel the key metabolic responses. By analyzing the intracellular carbon fluxes as well as the energy and cofactor utilization under different conditions, we uncovered varied metabolic responses to different inhibitors. Under acetate stress, ATP and NADH production was slightly impaired, while NADPH tended towards overproduction. Under furfural stress, ATP and cofactors (including both NADH and NADPH) tended to be overproduced. However, under dual-stress condition, production of ATP and cofactors was severely impaired due to synergistic stress caused by the simultaneous addition of two fermentation inhibitors. Such phenomenon indicated the pivotal role of the energy and cofactor utilization in resisting the mixed inhibitors of acetic acid and furfural. Based on the discoveries, valuable insights are provided to improve the tolerance of S. cerevisiae strain and further enhance lignocellulosic fermentation.

Structural and biochemical characteristics of chitin-binding protein SeCBP66 from Spodoptera exigua (Hübner)

Peritrophic membrane proteins are important components of the insect peritrophic membrane. A novel cDNA gene encoding a chitin-binding protein, named secbp66, was identified by immunization screening of the cDNA library of Spodoptera exigua. The full length of secbp66 is 1806 bp, which encodes 602 amino acids. The predicted weight of the protein is 64.2 kDa. Bioinformatic analysis showed that a signal peptide composed of 17 amino acids located at the N-terminal of SeCBP66 contained seven tandem putative Type-II functional chitin-binding domains and five potential N-glycosylation sites, but no O-linked glycosylation sites. To study the properties of SeCBP66, recombinant SeCBP66 was successfully expressed in the insect cell line BTI-Tn-5B1-4 with a Bac-to-Bac expression system. A chitin binding experiment showed that the recombinant SeCBP66 protein could bind to chitin strongly. This study of the novel chitin-binding protein SeCBP66 provides a basis for developing new control targets for S. exigua.

A weighted scoring system to differentiate malignant liposarcomas from benign lipomas

PURPOSE

To construct a scoring system to differentiate malignant liposarcomas from benign lipomas by comparing their clinical and magnetic resonance imaging (MRI) features.

METHODS

Clinical and MRI features of 33 women and 33 men aged 17 to 83 (mean, 53) years who underwent resection of malignant liposarcomas (n=32) or benign lipomas (n=34) were reviewed.

RESULTS

The 5 strongest predictors of liposarcoma were male gender, larger tumour maximum dimension, deep to fascia, thick non-fatty septum or nodule, and internal cystic change. A weighted scoring system was constructed using the 5 strongest predictors as: Z score=10X1+X2+12X3+15X4+10X5, respectively. A cut-off score of 35 was used; all 32 malignant liposarcomas and 4 of 34 benign lipomas scored >35. The cut-off score of ≤35 could predict 30 of 66 lipomatous tumours as benign with a negative predictive value of 100% (p<0.0001).

CONCLUSION

The 5 strongest clinical and MRI features were identified to construct a scoring system to differentiate malignant from benign lipomatous tumours. Further validation in independent populations is required.

[Drug coated balloon with paclitaxel for the treatment of symptomatic peripheral artery disease: early and midterm results]

OBJECTIVE

To evaluate the safety and efficacy of the drug coated balloon (DCB) with paclitaxel in patients with symptomatic peripheral artery disease (PAD).

METHODS

The clinical data of 18 patients, who were diagnosed as PAD and treated with DCB from October 2013 to June 2014 in Department of Vascular Surgery, People's Liberation Army General Hospital, were retrospectively analyzed.Thirteen male and 5 female patients were in the series, the mean age of the patients was (65±7) years, and the Rutherford's categories were level 3 to 5. Patients were followed up at 3- and 6-month postoperative. The main efficacy end point were late lumen loss(LLL), rate of restenosis and clinically driven target lesion revascularization (TLR). Meanwhile, the clinical events were recorded.

RESULTS

Mean lesion length, the percentage of total occlusions and the percentage of in-stent restenosis were (138±91) mm, 9/18 and 2/18, respectively. Rate of technical success was 18/18. At 6-month postoperative, LLL, rate of restenosis and TLR were (0.1±0.9) mm, 2/14 and 0, respectively. There was no deaths or no amputations.

CONCLUSION

DCB with paclitaxel is safe in patients with PAD, and associated with reductions in LLL, restenosis and clinically driven TLR 6-month postoperative.

[Reconstruct abdominal aortic branch arteries totally by endovascular repair in complex aortic aneurysms: a single-centre experience]

OBJECTIVE

To report experiences and results of complex aortic aneurysms involving the visceral arteries treating by total endovascular repair.

METHODS

Seventy cases of thoracoabdominal aortic lesions treating by total endovascular repair in Department of Vascular Surgery, People's Liberation Army General Hospital from January 2011 to December 2014 were retrospectively analyzed. There were 47 cases underwent chimney technique, 6 underwent sandwich technique, 15 underwent fenestration technique and 2 underwent branched stent grafts technique.

RESULTS

The average follow-up time was 21 months, range from 3 to 47 months. Completion angiography showed that typeⅠ endoleak of chimney, sandwich, fenestration and branched stent grafts group were 9/47, 5/6, 2/15 and 0, respectively. While at 30-day typeⅠ endoleak reduced to 7/47, 2/6, 0 and 0. During follow-up, there were 3 target vessel stents occlusion in chimney group, the patency rate of target vessel stent was 95.1% (58/61). In sandwich, fenestration and branched stent grafts group, all the target vessel stents kept patent.

CONCLUSION

In this study, chimney, sandwich, fenestration and branched stent grafts techniques show good short-term and midterm results, the long-term effects still need further studies.

[Behaviors on drug-abuse and prevalence of sexually transmitted diseases among drug users in Tianjin, China, from 2011 to 2015]

OBJECTIVE

To understand the change of behavioral characteristics among drug users (DUS) in Tianjin and the prevalence rates of major sexually transmitted disease infections. A series of cross-sectional surveys were used.

METHODS

Between April and June, 2011 to 2015, a cross-sectional survey with face to face interview, was undertaken. Interview was conducted among DUS who entered the drug rehabilitation center and blood samples were drawn to test for HIV/syphilis/HCV infections. Multivariate logistic regression analysis was used to analyze the relationship between the infection of major sexually transmitted diseases and drug abuse or sexual behavior.

RESULTS

2 000 DUS were included during the 5-year study, with the average age of the DUS as 34.5 ± 8.7. Female accounted for 17.9% and club drug (new drugs) users accounted 45.4% of the participants, with its proportion increasing over the years. Comparing to traditional drug users, club drug users showed more sexual activities with partners, but lower proportion of condom use. Prevalence rates of HIV/Syphilis and HCV were 1.3%, 11.0%, 52.0%, respectively. The prevalence of syphilis among club drug users was significantly higher than those on traditional-drug use (χ(2)=67.778,P<0.001). Data from Binary logistic regression analysis showed that club drug use (adjusted OR=1.607, 95% CI:1.191-2.170) and females (adjusted OR=5.287, 95%CI: 3.824-7.311) were associated with syphilis infection among DUS.

CONCLUSION

Drug abuse behavior changed among the drug abuse in Tianjin. Proportion of club drug use continued to increase so as the risk of infected sexually transmitted diseases.

[Characteristics of HIV infections among over 50-year-olds population in China]

OBJECTIVE

To analyze the characteristics on demographical, spatial distribution and transmission mode of HIV infections among 50-year-old population.

METHODS

Related information on demography, spatial distribution, high risk behavioral and history of HIV infections among 50-year-old population were collected and analyzed. Possible time of infection based on their first CD4 testing results right after the HIV diagnoses, was estimated.

RESULTS

Since 2008, the number of new HIV/AIDS cases among the over-50-year-olds was reported increasing annually. The number of aged 50 and above in 2014 was 4.2 times than the number in 2008. 50-year-old or older population were infected mainly through heterosexual behavior (88.0%). Among these cases, 83.9% self-reported as having histories on extramarital sex intercourse and the number was increasing yearly. Among male cases who admitted as having heterosexual experience, 95.1% of them reported as having histories of extramarital sex intercourse while 53.4% of the female cases reported as having the same experiences. 46.6% of spouses of the females or with fixed partners were HIV positive. Through estimating the time of infection and the time interval between infection and diagnosis, we found that the proportion was 15.5%, from infection to diagnosis as 3 years among the 50 and older age groups, but the proportion of 8 years from infection to diagnosis was 43.6%. We estimated that 66.5% of the new HIV cases who were at age 50 and over, were infected when they were at that age span. The average time from infection and being tested was (6.8 ± 2.7) years.

CONCLUSION

The increasing number of being diagnosed on HIV among the 50-year-olds population might be related to both high risk exposure and belated diagnoses among this population, calling for the necessity of deriving the sources of HIV infection and tailoring the HIV prevention strategies in this population.

The split Renilla luciferase complementation assay is useful for identifying the interaction of Epstein-Barr virus protein kinase BGLF4 and a heat shock protein Hsp90

Protein-protein interactions can regulate different cellular processes, such as transcription, translation, and oncogenic transformation. The split Renilla luciferase complementation assay (SRLCA) is one of the techniques that detect protein-protein interactions. The SRLCA is based on the complementation of the LN and LC non-functional halves of Renilla luciferase fused to possibly interacting proteins which after interaction form a functional enzyme and emit luminescence. The BGLF4 of Epstein-Barr virus (EBV) is a viral protein kinase that is expressed during the early and late stages of lytic cycles, which can regulate multiple cellular and viral substrates to optimize the DNA replication environment. The heat shock protein Hsp90 is a molecular chaperone that maintains the integrity of structure and function of various interacting proteins, which can form a complex with BGLF4 and stabilize its expression in cells. The interaction between BGLF4 and Hsp90 could be specifically detected through the SRLCA. The region of aa 250-295 of BGLF4 is essential for the BGLF4/Hsp90 interaction and the mutation of Phe-254, Leu-266, and Leu-267 can disrupt this interaction. These results suggest that the SRLCA can specifically detect the BGLF4/Hsp90 interaction and provide a reference to develop inhibitors that disrupt the BGLF4/Hsp90 interaction.

DNA Demethylation Rescues the Impaired Osteogenic Differentiation Ability of Human Periodontal Ligament Stem Cells in High Glucose

Diabetes mellitus, characterized by abnormally high blood glucose levels, gives rise to impaired bone remodeling. In response to high glucose (HG), the attenuated osteogenic differentiation capacity of human periodontal ligament stem cells (hPDLSCs) is associated with the loss of alveolar bone. Recently, DNA methylation was reported to affect osteogenic differentiation of stem cells in pathological states. However, the intrinsic mechanism linking DNA methylation to osteogenic differentiation ability in the presence of HG is still unclear. In this study, we found that diabetic rats with increased DNA methylation levels in periodontal ligaments exhibited reduced bone mass and density. In vitro application of 5-aza-2′-deoxycytidine (5-aza-dC), a DNA methyltransferase inhibitor, to decrease DNA methylation levels in hPDLSCs, rescued the osteogenic differentiation capacity of hPDLSCs under HG conditions. Moreover, we demonstrated that the canonical Wnt signaling pathway was activated during this process and, under HG circumstances, the 5-aza-dC-rescued osteogenic differentiation capacity was blocked by Dickkopf-1, an effective antagonist of the canonical Wnt signaling pathway. Taken together, these results demonstrate for the first time that suppression of DNA methylation is able to facilitate the osteogenic differentiation capacity of hPDLSCs exposed to HG, through activation of the canonical Wnt signaling pathway.

Clinical application of highly agglutinative staphylococcin in cancer treatment updates of the literature

This review article summarized 100 published research papers and reviewed the application status of highly agglutinative staphylococcin in the clinical treatment of cancer. Highly agglutinative staphylococcin (HAS) derives from the superantigen of Staphylococcus aureus metabolite. Studies have shown that HAS can inhibit and kill tumors, repair tissues and cells, increase white blood cell count and improve the immune function. Its immunological effect acts through the following mechanism: activating T-cells and natural killer cells, enhancing phagocytes' phagocytosis and killing ability of lymphocytes, increasing white blood cell count in peripheral blood, repairing impaired histocytes, and inhibit the growth of tumor cells. Highly agglutinative staphylococcin is used in clinical treatment of tumors: intracavitary hyperthermic perfusion with single HAS is effective for malignant ascites; perfusion with HAS plus chemotherapeutics can remarkably improve the elimination rate of ascites. Highly agglutinative staphylococcin can also enhance the effect of and improve the response rate of chemotherapy and radiotherapy, and improve patients' immune function and relieve gastrointestinal reactions caused by radiotherapy and chemotherapy. Therefore, HAS is used to treat a malignant tumor, leucocytopenia, and malignant ascites, and relieve side effects caused by radiotherapy and chemotherapy and improve patients' immune function.

Outcomes of intracytoplasmic sperm injection in oligozoospermic men with Y chromosome AZFb or AZFc microdeletions

We investigated whether the presence of Y chromosome azoospermia factor (AZF) microdeletions impacts upon the outcomes of intracytoplasmic sperm injection (ICSI) using fresh ejaculated spermatozoa. Sixteen oligozoospermia patients with Y chromosome AZFb or AZFc microdeletions and undergoing ICSI cycles between March 2013 and November 2014 were studied. Twenty-six infertile men with normal Y chromosomes and also undergoing IVF/ICSI in the same time period were used as controls. A retrospective case-control study approach was used. Among the 16 cases, 12 (75%, 12/16) had deletions of AZFc markers (sY152, sY254 and sY255), one (6.25%, 1/16) had a deletion of sY152, and two (12.5%, 2/16) had deletions of sY152, sY254, sY255 and sY157. AZFb microdeletions were found in one patient (6.25%, 1/16). There were no significant differences between groups for cleaved embryo rate, high-grade embryo rate, blastocyst formation rate, embryo implantation rate, clinical pregnancy rate and delivery rate. The clinical outcomes of ICSI for oligozoospermic patients with Y chromosome AZF microdeletion are comparable to those of infertile patients with normal Y chromosomes. Our findings indicate that ICSI should be offered to patients with an AZFc deletion and that oligozoospermia patients with AZFb microdeletions are likely to father children.

Design and simulation of two-section DFB lasers with short active-section lengths

Distributed feedback lasers comprised of a reflection section and an active section have been proposed for high direct-modulation bandwidth. The reflection section has the same core layer as the active section so butt-joint re-growth is avoided. Without current injection the reflection section will be pumped to near transparency by the emission from the laser itself so high reflection (> 0.75) can still be achieved as confirmed by the simulation. Therefore a short (150 µm) active section can be used, which enables a low threshold current (~5 mA) and a high direct modulation bandwidth (>30 GHz) as demonstrated by the simulation.