IMPLICITIZATION OF RATIONAL CURVES AND POLYNOMIAL SURFACES

Yu, Jian-Ping,Sun, Yong-Li Korean Mathematical Society 2007 대한수학회보 Vol.44 No.1

In this paper, we first present a method for finding the implicit equation of the curve given by rational parametric equations. The method is based on the computation of $Gr\"{o}bner$ bases. Then, another method for implicitization of curve and surface is given. In the case of rational curves, the method proceeds via giving the implicit polynomial f with indeterminate coefficients, substituting the rational expressions for the given curve and surface into the implicit polynomial to yield a rational expression $\frac{g}{h}$ in the parameters. Equating coefficients of g in terms of parameters to 0 to get a system of linear equations in the indeterminate coefficients of polynomial f, and finally solving the linear system, we get all the coefficients of f, and thus we obtain the corresponding implicit equation. In the case of polynomial surfaces, we can similarly as in the case of rational curves obtain its implicit equation. This method is based on characteristic set theory. Some examples will show that our methods are efficient.

Implicitization of rational curves and polynomial surfaces

Jian-ping Yu,Yong-li Sun 대한수학회 2007 대한수학회보 Vol.44 No.1

Pathologic Response During Chemo-radiotherapy and Variation of Serum VEGF Levels Could Predict Effects of Chemo-Radiotherapy in Patients with Esophageal Cancer

Yu, Jing-Ping,Lu, Wen-Bin,Wang, Jian-Lin,Ni, Xin-Chu,Wang, Jian,Sun, Zhi-Qiang,Sun, Su-Ping Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.3

Background: To investigate the relationship between pathologic tumor response to concurrent chemoradiotherapy and variation of serum VEGF in patients with esophageal cancer. Materials and Methods: Forty six patients with esophageal cancer who were treated with concurrent chemo-radiotherapy were enrolled. Endoscopic and pathologic examination was conducted before and four weeks afterwards. Serum level of VEGF was documented before, four weeks later and after chemo-radiotherapy. The relationship between pathologic response and the variation of serum level of VEGF and its influence on the prognosis were investigated. Results: Serum level of VEGF decreased remarkably during and after chemo-radiotherapy in patients whose pathologic response was severe (F=5.393, 4.587, P(0.05). There were no statistical differences of serum VEGF level before, during and after chemo-radiotherapy for patients whose pathologic response was moderate or mild. There were 18 (85.7%), 7 (53.8%) and 6 patients (50.0%) whose serum VEGF level dropped in the severe, moderate and mild group, respectively, with significant differences among these groups (p=0.046). Two year survival rates of patients with severe, moderate and mild pathologic response were 61.9%, 53.8% and 33.3% respectively, and no statistically difference between severe and mild group regarding OS (p=0.245) was tested. Conclusions: Tumor pathologic response during chemo-radiotherapy and the changes of serum VEGF lever could predict curative effects of chemo-radiotherapy in patients with esophageal cancer.

Ethosomes, Binary Ethosomes and Transfersomes of Terbinafine Hydrochloride: A Comparative Study

Jian-Ping Zhang,Xin-An Wu,Yu-Hui Wei,Yan Zhou,Yu-Qing Li 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.1

The aim of this study was to compare the skin permeation of ethosomes, binary ethosomes and transfersomes of Terbinafine Hydrochloride (TH) under non-occlusive conditions. These lipid vesicles were prepared and characterized for shape, size, zeta-potential and entrapment efficiency. Franz diffusion cells and confocal laser scanning microscopy (CLSM) were used for the percutaneous absorption studies. The quantity of drug in the skin from ethosomes, binary ethosomes (the weight ratio of ethanol to propylene glycol 7:3, ethanol-PG = 7:3, w/w), and transfersomes was 1.26, 1.51 (p <0.05), 1.56 (p <0.01) times higher than that of TH from traditional liposomes (control). The skin deposition of the applied dose (DD%) of TH from ethosomes, binary ethosomes, and transfersomes was 3.34 (p < 0.05), 9.88 (p < 0.01), 2.52 times higher than that of TH from control. The results of CLSM experiments showed that penetration depth and fluorescence intensity of Rhodamine B from binary ethosomes was much greater than that from ethosomes and transfersomes. These results indicated the binary ethosomes (ethanol-PG = 7:3, w/w) most effectively permitted drug penetration through skin; transfersomes made drug easiest to accumulate in the skin. Ethosomes improved drug delivery with greater improvement in skin permeation than improvement in skin deposition.

Outcomes Based on Risk Assessment of Anastomotic Leakage after Rectal Cancer Surgery

Gong, Jian-Ping,Yang, Liu,Huang, Xin-En,Sun, Bei-Cheng,Zhou, Jian-Nong,Yu, Dong-Sheng,Zhou, Xin,Li, Dong-Zheng,Guan, Xin,Wang, Dong-Feng Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.2

Purpose: Anastomotic leakage (AL) is associated with high morbidity and mortality, high reoperation rates, and increased hospital length of stay. Here we investigated the risk factors for AL after anterior resection for rectal cancer with a double stapling technique. Patients and Methods: Data for 460 patients who underwent primary anterior resection with a double stapling technique for rectal carcinoma at a single institution from 2003 to 2007 were prospectively collected. All patients experienced a total mesorectal excision (TME) operation. Clinical AL was defined as the presence of leakage signs and confirmed by diagnostic work-up according to ICD-9 codes 997.4, 567.22 (abdominopelvic abscess), and 569.81 (fistula of the intestine). Univariate and logistic regression analyses of 20 variables were undertaken to determine risk factors for AL. Survival was analysed using the Cox regression method. Results: AL was noted in 35 (7.6%) of 460 patients with rectal cancer. :Median age of the patients was 65 (50-74) and 161 (35%) were male. The diagnosis of AL was made between the 6th and 12th postoperative day (POD; mean 8th POD). After univariate and multivariate analysis, age (p=0.004), gender (p=0.007), tumor site (p<0.001), preoperative body mass index (EMI) (p<0.001), the reduction of TSGF on 5th POD less than 10U/ml (p=0.044) and the pH value of pelvic dranage less than or equal to 6.978 on 3rd POD (p<0.001) were selected as 6 independent risk factors for AL. It was shown that significant differences in survival of the patients were AL-related (p<0.001), high ASA score related (p=0.036), high-level EMI related (p=0.007) and advanced TNM stage related <p<0.001). Conclusions: AL after anterior resection for rectal carcinoma is related to advanced age, low tumor site, male sex, high preoperative EMI, low pH value of pelvic drainage on POD 3 and a significant reduction of TSGF on POD 5. In addition to their high risk of immediate postoperative morbidity and mortality, AL, worse physical status, severe obesity and advanced TNM stage have similarly negative impact on survival.

The genome of Bacillus aryabhattai T61 reveals its adaptation to Tibetan Plateau environment

Ping Wan,ZhiWei Yang,Yan Yan,Lei Zhang,MengYao Yu,Jian Wang,He Tang 한국유전학회 2016 Genes & Genomics Vol.38 No.3

Tibetan Plateau is called ‘the Roof of the World’. Organisms survive there have to adapt to the high altitude environment. By shotgun method, we sequenced the genome of Bacillus aryabhattai T61, which inhabits in the soil at the altitude of 4123 m in Shigatse, Tibetan. Further, we explored the genomic basis for its adaptations to the plateau environment. The results showed that B. aryabhattai T61 has evolved an array of ROS defense systems and sporulation system for adaptations to the stresses caused by the plateau strong ultraviolet radiation, extreme oxygen limitation and low temperature. Specifically, B. aryabhattai T61 encodes the ResE–ResD twocomponent to sense the oxygen limitation and regulates COX15 for aerobic and anaerobic respiration. The twocomponent system DesK–DesR, which regulates the gene Des initiating the biosynthesis of unsaturated fatty acids, along with 33 temperature-shock proteins contribute to low temperature adaptation. With the comparative analysis, we deduced the novel gene cbiY may be involved in cobalamin biosynthesis. We also found that B. aryabhattai T61 may have novel regulatory mechanisms for sporulation initiation. B. aryabhattai T61 is the first Tibetan strain with high quality genome sequenced. The genome provides a paradigm for understanding the adaptations to the plateau environment in Bacteria kingdom.

Prevalence, Risk Factors, and Psychological Effects of Overactive Bladder in Chinese University Students

Yu Liang,Guo Wei Si,Hui Jie Hu,Zhen Wei Zhang,Cui Ping Song,Qi Feng Dou,Jian Guo Wen 대한배뇨장애요실금학회 2022 International Neurourology Journal Vol.26 No.4

Purpose: The purpose of this study was to investigate the prevalence and risk factors of overactive bladder (OAB) in young adults and to explore the influence of OAB on mental health. Methods: Between October 2019 and January 2020, 14,010 anonymous questionnaires were distributed to freshmen at 2 universities in Henan, China. The students came from all over the country. The questionnaire included general items and information necessary to calculate the overactive bladder symptom score, the Chinese version of the Pittsburgh Sleep Quality Index (PSQI) score, Self-Esteem Scale (SES) score, and Self-Rating Depression Scale (SDS) score. The relationships between the prevalence of OAB and its risk factors were evaluated. Results: The overall prevalence of OAB was 6.0%, with 4.3% of participants characterized as having dry OAB and 1.7% as having wet OAB. The prevalence of mild OAB was 5.5%, and that of moderate OAB was 0.5%; no severe OAB was observed. Higher prevalence rates of OAB were found among women, respondents with constipation, and respondents with primary nocturnal enuresis (PNE) (P <0.05). Compared to healthy controls, the OAB group exhibited a higher mean SDS score (52.12±8.986 vs. 47.71±9.399, P<0.001) and mean PSQI score (5.28±2.486 vs. 4.27±2.431, P<0.001), but a lower mean SES score (27.78±3.599 vs. 29.57±4.109, P<0.001). Conclusions: OAB significantly affects the mental health of young adults. Female sex, constipation, and PNE are risk factors for OAB.

Expression, Purification, and Biological Characterization of The Amino-Terminal Fragment of Urokinase in Pichia pastoris

( Jian Ping Li ),( Yu Li Lin ),( Hong Qin Zhuang ),( Zi Chun Hua ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.9

Urokinase (uPA) and its receptor (uPAR) play an important role in tumor growth and metastasis. Targeting the excessive activation of this system as well as the proliferation of the tumor vascular endothelial cell would be expected to prevent tumor neovasculature and halt the tumor development. In this regard, the amino-terminal fragment (ATF) of urokinase has been confirmed as effective to inhibit the proliferation, migration, and invasiveness of cancer cells via interrupting the interaction of uPA and uPAR. Previous studies indicated that ATF expressed in Escherichia coli was mainly contained in inclusion bodies and also lacked posttranslational modifications. In this study, the biologically active and soluble ATF was cloned and expressed in Pichia pastoris. The recombinant protein was purified to be homogenous and confirmed to be biologically active. The yield of the active ATF was about 30 mg/l of the P. pastoris culture medium. The recombinant ATF (rATF) could efficiently inhibit angiogenesis, endothelial cell migration, and tumor cell invasion in vitro. Furthermore, it could inhibit in vivo xenograft tumor growth and prolong the survival of tumor-bearing mice significantly by competing with uPA for binding to cell surfaces. Therefore, P. pastoris is a highly efficient and cost-effective expression system for large-scale production of biologically active rATFs for potential therapeutic application.

Geometrical and Magnetic Properties of Vanadium Clusters Supported on Graphene

Yu Zou,Chang Yong Zhan,Jian-Chun Wu,Li-Ping Zhou,Hai-Xia Da 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.2

We report ab-initio calculations of vanadium-cluster Vn(n = 2−5) adsorption on graphene sheets. Geometrical and magnetic properties of various adsorption configurations are studied using firstprinciples density-functional theory with the generalized gradient approximation. The geometrical and magnetic properties of vanadium clusters are found to be size-dependent, and the supported graphene sheet could influence the formation of the vanadium clusters. Low-dimensional Vn cluster configurations could be easily formed when they are absorbed on a graphene sheet, and the combined Vn-graphene systems exhibit a nonmagnetic state, which is the most stable magnetic configuration. Our calculations for the geometrical and the magnetic moment properties of Vn-graphene systems may be of interest for some nanotechnological applications.

Adjusting optical resonance thickness to increase the conversion efficiency of polymer solar cells

Yu Sheng Tsai,Jian-Shian Lin,Wei-Ping Chu,Po-Hsun Wang,Fuh-Shyang Juang,Ming-Hua Chung,Chin-Ming Chen,Mark O. Liu 한국물리학회 2010 Current Applied Physics Vol.10 No.3

The derivatives of C60, [6,6]-phenyl C61-butyric acid methyl ester (PCBM), and 3-hexylthiophene (P3HT)were dissolved in DCB solvent, then spin coated into an active layer for polymer solar cells. The experimental parameters were studied carefully to obtain the optimum power conversion efficiency (PCE). The primary process for generation of photocurrent in an organic photovoltaic device is the generation of bound electron–hole pairs (excitons) by absorption of energy (photons) from the optical electric field. Modeling was based on the assumption that the photocurrent generation process is the result of the creation and diffusion of photogenerated species (excitons), which are dissociated by charge transfer at the active layer. Improve organic optics absorb by insert organic layer (CuPc or C60) at the active layer/Al interface. This research is divided into two components. First part, we use n-type C60 as transmission layer. When an optimum thickness of C60 is 5 nm, the Jsc of polymer solar cell can be increased from 7.26 mA/㎠ to 7.7 mA/㎠. The Voc decrease is because the energy level of C60 LUMO (lowest unoccupied molecular orbital) at 4.5 eV is higher than the 3.7 eV of PCBM. Second part, we use p-type CuPc as transmission layer. When an optimum thickness of CuPc is 3 nm, the short circuit photo-current density (Jsc) and open circuit voltage (Voc) of polymer solar cell can be increased from 7.26 mA/㎠ to 8.0 mA/㎠ and 0.56–0.58 V, respectively. The reason is the same as C60. The Voc increase is because the energy level of CuPc LUMO (lowest unoccupied molecular orbital) at 3.1 eV is lower than the 3.7 eV of PCBM. The Jsc increase is because the 3 nm of CuPc leads to a constructive interference happened in the active layer and thus optical absorption increases. In this study we used 3 nm of CuPc at the active layer/Al interface to enhance the short circuit current density, and the efficiency was increased to 2.94%.