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Orbital correlation of space objects is one of the most important elements in space object identification. Using the orbital elements, we provide correlation criteria to determine if objects are coplanar, co-orbital or the same. We analyze the prediction error of the correlation parameters for different orbital types and propose an orbital correlation method for space objects. The method is validated using two line elements and multisatellite launching data. The experimental results show that the proposed method is effective, especially for space objects in near-circular orbits.

In the present paper, the natural pyrite was the sample. With the UV-visible near-infrared spectrophotometer Cary 500, we measured the absorption and reflection spectra of the sample within 200-2 000 nm range, calculated the absorption coefficient and figured out the forbidden band of the sample according to the Tauc regulation. The authors discovered that the light absorption coefficient of natural pyrite measured is 10(5) order of magnitude; in the absorption pattern we found obvious shoulder line structure and we can judge that the sample belongs to indirect forbidden band semiconductor, its forbidden band was 0.64 eV in width and the "limit conversion efficiency" corresponding to 0.64 eV could reach 14% or so. With the comparison of the results of this paper and the forbidden band of the solar battery materials at present in common, this paper mainly analyzed the effect of the light absorption coefficient and forbidden band on the photoelectric conversion efficiency of pyrite. The authors found that its high absorption coefficient provided the possibility that pyrite will be used as solar battery with the film form, but its forbidden band was narrower than the theoretical number. The authors could broaden its forbidden band or make composite films to use.

To investigate characteristics of cervical cytology and management in pregnant women.From Aug. 2006 to Jan. 2010, 5152 pregnant women who received antenatal and postpartum examination underwent cervical cytological screening by liquid-based cytological test (LCT) in China-Japan Friendship Hospital. The cytological diagnosis was in accordance with the Bethesda system (TBS) 2001 diagnosis and classification system. The abnormal LCT results were followed up at 3 months after postpartum. The diagnosis of high-grade squamous intraepithelial lesions (HSIL) and squamous cell carcinoma (SCC) were based on colposcopic examination and biopsy during pregnant. The diagnosis of atypical glandular cells (AGC) was based on curettage and biopsy at postpartum 6 weeks. The histopathology of biopsy were compared and analyzed.(1) Cervical cytological changes related with pregnancy: among 5152 cases, it was found navicular cells in 3215 cases (62.40%), decidual cells in 783 cases (15.20%), reactive glandular cells in 369 cases (7.16%), and trophoblastic cells in 55 cases (1.07%). (2) LCT results: among 5152 cases, the normal samples were 4125 cases (80.07%), the inflammatory samples were 542 cases (10.52%), and the samples of abnormal epithelial cells were 485 cases (9.41%). Among those abnormal cases, 291 cases (5.65%) were in atypical squamous cells (ASC), 153 cases (2.97%) were in low-grade squamous intraepithelial lesions (LSIL), 33 cases (0.64%) were in HSIL, 1 case (0.02%) were in SCC and 7 cases (0.14%) were in AGC. (3) Histological pathology results: all women with HSIL and SCC underwent colposcopic examination and biopsy, it was found 28 cases in cervical intraepithelial neoplasia (CIN)II-III, 1 cases in adenosquamous carcinoma. 7 women underwent curettage and biopsy at postpartum 6 weeks which were diagnosed by AGC, the histopathological diagnosis was all negative. The concordance rate of cytopathologic and histopathologic diagnosis was 71% (29/41). (4) FOLLOW-UP: 485 women with abnormal LCT results were all followed up to 3 months at postpartum. Women with HSIL, SCC and AGC undergoing biopsy showed normal LCT results during follow-up. Those women with ASC and LSIL did not undergo colposcopic examination and biopsy. The regression rate was 72.3% (321/444) at postpartum 3 months.The navicular cells were primarily morphological characteristics of cytology during pregnant and postpartum women. Some changes were easily confused with malignant lesions. It should be careful discrimination, and avoid excessively diagnosis and misdiagnosis. It suggested that we should follow up those women closely and expand the indication of colposcopic biopsy.

IANT hydronephrosis is a rare urological entity. It was first defined as the presence of more than 1 000 mL of fluid in the collecting system. That disease is seen more often in males than in females (2.4..1) and more often on the left side than on the right side (1.8..1). It is usually secondary to ureteropelvic junction obstruction, stone, or congenital abnormality. Among the etiologies of giant hydroureteronephrosis, obstruction of ectopic ureteral orifice into prostatic urethra is a very rare one. Most of the cases are diagnosed and treated in infancy or childhood. However, some patients remain asymptomatic until later in life. Adults may present with intermittent abdominal or flank pain, renal insufficiency, urinary tract infection, or gross hematuria after minor trauma. Here we report a unique case of a giant hydroureteronephrosis associated with ipsilateral inguinal hernia and contralateral hydronephrosis to contribute to better understanding of this disease.

In this paper, we prepared a novel cationic self-assembled micelle from poly(epsilon-caprolactone)-poly(ethyl glycol)-poly(epsilon-caprolactone) grafted polyethyleneimine (PCEC-g-PEI). The PCEC-g-PEI micelles, formed by self-assembly method, had mean particle size of ca. 82 nm and zeta potential of +22.5 mV at 37 degrees C, and could efficiently transfer pGFP into HEK293 cells in vitro. Meanwhile, as a model hydrophobic chemotherapeutic drug, honokiol was loaded into PCEC-g-PEI micelles by direct dissolution method assisted by ultrasonication. The honokiol loaded cationic PCEC-g-PEI micelles could effectively adsorb DNA onto its surface, while it could release honokiol in an extended period in vitro. This study demonstrated a novel DNA and hydrophobic chemotherapeutic drug co-delivery system.

In this study, a series of porous scaffolds were prepared from poly(D,L-lactide) (PLA) and nanohydroxyapatite (HA) using the phase separation method. HA/PLA composite membranes and PLA membranes with a microporous structure (pore size around 10-20 μm) were observed by scanning electron microscopy and these micropores were well distributed throughout the PLA membranes. The surface morphology of HA/PLA composite membranes was significantly improved compared to pure PLA membrane. Also, the mechanical property and contact angle of composite membranes were different from that of pure PLA films. The immortalized rat osteoblastic ROS 17/2.8 cell line was used in this research to study the cell adhesion and proliferation behavior, and the results indicated that composite membranes had great cell affinity and good biocompatibility.

Nano-hydroxyapatite (n-HA)/poly(e-caprolactone)-poly(ethylene glycol)-poly(e–caprolactone) (PCL-PEG-PCL, PCEC) composite membranes were prepared by solvent casting and evaporation method. The structure and properties of the membranes were investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), water contact angle measurements, in vitro hydrolytic degradation, mechanical test, and cell culture. The effect of n-HA content on physical–chemical properties of the n-HA/PCEC composite membranes was studied. The results showed that the shape and size of micropores of the composite membranes changed with n-HA content increased; the tensile strength decreased with the increase of n-HA content. The osteoblast cell was cultured on the membranes, good cell attachment and growth manner were observed after postseeding for 1 day. MTT assays showed that the n-HA/PCEC membranes had no negative effect on the cell viability and proliferation. These results suggested that the obtained n-HA/PCEC composite membranes in this study might have prospective applications in tissue engineering field. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.

In this study, cucumber seedlings were cultivated in nutrient solution added with different concentration (0.05, 0.1, 0.2, and 0.3 mmol x L(-1)) sodium nitroprusside (SNP) as nitric oxide (NO) donor to study the effects of exogenous NO on the growth of cucumber seedlings and the activities of antioxidant enzymes in cucumber leaves under NO3- stress. Under the stress of 140 mmol x L(-1) NO3-, treating with 0.1 mmol x L(-1) of SNP for 1 d or 7 d increased the leaf soluble protein content and superoxidase (SOD), catalase (CAT), and ascorbic acid peroxidase (APX) activities, and decreased the leaf malondialdehyde (MDA) content significantly, suggesting that exogenous NO could enhance the capacity of cucumber seedlings in scavenging active oxygen species, protect the seedlings from the peroxidation of membrane lipids, and promote the seedlings growth and increase their resistance to high concentration NO3- stress. After the cucumber seedlings grew in 0.3 mmol x L(-1) of SNP for 7 d, the activities of leaf SOD, POD, and CAT decreased, and the MDA content increased, resulting in the injury of cucumber seedlings. It was indicated that certain concentration (0.1-0.2 mmol x L(-1)) exogenous NO could alleviate the NO3- stress to cucumber seedlings.

Efficient timing synchronization for interleaves must be achieved first before signal detecting and decoding in an IDMA system. However, it is much more difficult to obtain the perfect timing information in IDMA systems than in CDMA systems, owing to the lack of spread gain, especially at the low signal-noise-ratio conditions. In this paper, a conventional sliding-correlate scheme is discussed and a novel scheme based on IDMA system, named Spreading-IDMA, is introduced. The fundamental principle is given and the performance is analyzed. The complexity and average time of the synchronization of the proposed scheme are much less than the conventional one.

In order to overcome the shortcomings of existing MAC protocols based on TDMA or CDMA in satellite networks, IDMA technique is introduced into satellite communication networks for the first time, and a novel IDMA-based MAC protocol is proposed in this paper. Due to the potential advantages of IDMA, the proposed scheme avoids complex packet scheduling and slot management required in the existing MAC protocols. In the random access channel, the spread aloha method is adopted to alleviate collision of request packet, which improve the access probability in high load conditions. Throughput and delay performances are derived in detail for a given arrival rate of access requests. Analysis and numerical results show the efficiency of the proposed scheme, especially when the traffic load is high.

Phenethyl isothiocyanate (PEITC), a natural dietary isothiocyanate, has anti-cancer activity in various in vitro and in vivo models. PEITC inhibits angiogenesis but the molecular mechanisms that underlie this effect are not known. We have now demonstrated that PEITC is an effective inhibitor of hypoxia inducible factor (HIF), a transcription factor that plays an important role in expression of pro-angiogenic factors. PEITC inhibited the activation of a HIF-dependent reporter construct following incubation of cells in hypoxia, or treatment with the hypoxia mimetic cobalt chloride. PEITC also interfered with the accumulation of HIF1alpha protein and induction of the endogenous HIF target genes, CAIX, GLUT1, BNIP3 and VEGF-A. The ability of PEITC to inhibit HIF activity was independent of the activity of prolyl hydroxylases, the Von-Hippel-Landau protein and the proteasome, all of which are required for the normal rapid turnover of HIF1alpha in normoxia. Decreased expression of HIF1alpha in PEITC treated cells was not associated with changes in the levels of HIF1alpha RNA suggesting that PEITC may inhibit HIF activity by decreasing translation of the HIF1alpha RNA. Consistent with this, PEITC decreased phosphorylation of the translation regulator 4E-BP1. Our data demonstrate that PEITC is an effective inhibitor of HIF activity. This may contribute to the anti-angiogenic and anti-cancer effects of PEITC.

To observe the serial changes of condition and related factors of Keshan disease (KSD) and provide the scientific basis for disease control and further research.The villages in KSD epidemic area of Juxian, Yishui, Pingyi, Zoucheng counties were selected. Since 1990, every five-year was counted as a stage. For the first to third stage, 3-14 year-old residents and over 14 year-old suspicious patients were selected as surveillance subjects. And in the fourth stage, all residents were selected as surveillance subjects. The same group of surveillance subjects in each stage were observed consecutively for 5 years. Surveillance contents included physical checkup, electrocardiogram (ECG) and Xray. At the same time, the selenium (Se) concentration in hair, wheat, corn and sweet potato was measured. The economic income and grain availability were also investigated.Totally, 14,510 cases were visited during 18 years. The incidence of KSD was 3.02% in the first stage, 2.31% in the second stage, 3.57% in the third stages and 3.65% in the fourth stage. Totally, 14,510 cases were examined by ECG, 809 cases showed the abnormal ECG and the total incidence of abnormal ECG was 5.49%. The incidence of abnormal ECG was 3.52% -5.24% from 1990 to 2004 but was 10.97%-10.91% from 2005 to 2007. 732 of hair samples, 701 of wheat samples, 615 of corn samples and 643 of sweet potato samples were collected and the Se concentration was determined by the fluorescent method. Se levels in hair samples had increased (P0.05) year by year but Se levels in food have not changed significantly. The economic income and grain availability had increased gradually from 535.8 yuan and 254.6 kg per person in 1990 to 2968.0 yuan and 602.0 kg per person in 2007.The condition of KSD was in a stable situation in Shandong Province. Related factors improvement should be an important environmental condition.

The purpose of this paper is to describe the large- scale atmosphere activities in the northern hemisphere by predigesting the model. Based on NCAR/NCEP reanalysis data, the oscillation of atmosphere circulation between Arctic and middle latitude are validated on EOF, and the wintertime planetary wave activities in the northern hemisphere are examined on 2D FFT and spectral analysis with focus on their spatial distribution and temporal-spatial characters respectively. The objective variables include sea level pressure (SLP) and anomaly stream function at 850 hPa, 500 hPa and 200 hPa. The analysis reveals that the wave numbers 1~2,1~3, and the wave numbers 1~4 dominate the perturbation pattern at 70deg~80degN, 60deg~70degN and 50deg~60degN zonal belt respectively. The results accord fairly well with Rossby's classical trough formula and are of potential use for understanding the northern hemisphere large-scale oscillations.

Based on fuzzy Takagi-Sugeno (T-S) model and variable structure control technique, the output tracking control problem for fuzzy time-delay systems in the existence of parameter perturbations is developed. Firstly, the sliding mode is chosen by variable structure control theory. According to reaching condition, the variable control method was proposed on condition that the time delay is precisely available and unavailable, respectively. The method guaranteed the trajectory of system to arrive the slide surface in finite time interval and be kept here thereafter. Secondly, the sufficient condition for globally bound of the state is proposed by using Input to state systems (ISS) theory and linear matrix inequality (LMI) method. Finally, simulation example is employed to illustrate the validity and effectiveness of the proposed method.

The problem of global optimal static output feedback control for linear time-invariant systems with linear quadratic index in the cases of random initial conditions and deterministic initial conditions was investigated. For the given initial condition (the random case), the necessary and sufficient condition - a matrix equation is obtained for the output feedback control to be equal to the optimal state feedback control and in this case, the output feedback is globally optimal. Further, for the deterministic case, the main contribution is to reveal the dependence of the global optimal feedback gain on the given initial condition. All results are described in a linear algebraic equation

BAG-1 is a multifunctional protein that exists as several differentially localised and functionally distinct isoforms. BAG-1 isoforms interact with a diverse array of molecular targets and regulate a wide range of cellular processes, including proliferation, survival, transcription, apoptosis, metastasis and motility. The BAG domain of BAG-1 interacts with chaperone molecules and this is considered important for many BAG-1 functions. The ability of BAG-1 to regulate such a wide variety of cellular processes suggests it might play an important role in many cancer types. For example, regulation of nuclear hormone receptor function and susceptibility to apoptosis might have a major impact on cancer development, progression and response to therapy. There is also increasing evidence that BAG-1 expression is altered in a variety of human malignancies relative to normal cells, and with further understanding of BAG-1 function it might become a powerful prognostic/predictive marker in human cancer. This review describes the structure and function of BAG-1 isoforms and the potential clinical implications of their expression in tumour cells.

Both the amino-terminal and carboxyl-terminal domains of IGF binding protein (IGFBP)-3 are believed to contribute to high-affinity IGF binding. To investigate cooperativity in IGF binding by these domains, we expressed IGFBP-3 fragments 1-88 (NBP-3) and 185-264 (CBP-3) as FLAG and hexahistidine-tagged fusion proteins, respectively. IGF-I and IGF-II bound to NBP-3 poorly and to CBP-3 with moderate affinities, approximately 1 liter/nmol. Coincubating the fragments in equimolar concentrations caused a significant cooperative increase in IGF binding, demonstrated by immunoprecipitation with IGFBP-3, FLAG, or hexahistidine antibodies. Equimolar NBP-3 + CBP-3 bound IGF-II with an affinity (12.2 liter/nmol) only 4-fold lower than that of the IGFBP-3-IGF-II complex and IGF-I with an affinity (3.2 liter/nmol) 13-fold lower than IGFBP-3-IGF-I. Heterotrimeric complexes of NBP-3, CBP-3, and IGF, also demonstrated by affinity labeling, bound acid-labile subunit poorly. Coprecipitation assays with iodinated NBP-3 or CBP-3 indicated that the fragments cannot interact unless IGF is also present. Complexing with NBP-3 + CBP-3 inhibited IGF stimulation of type 1 IGF receptor activity and IGF-II binding to the type II receptor. This study demonstrates that isolated amino-terminal and carboxyl-terminal domains of IGFBP-3 cooperate in the presence of IGFs to form high-affinity complexes that retain the ability to block IGF activity.

Qing Fa Guo, Ting Ting Liu, Xi Yan, Xiu Hong Wang, Shuai Shi, Feng Luo, Zhi Yong QianState Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of ChinaBackground: Gene therapy is a promising approach to the treatment of a wide range of diseases. The development of efficient and adequate gene delivery systems could be one of the most important factors. Polyethyleneimine, a cationic polymer, is one of the most successful and widely used vectors for nonviral transfection in vitro and in vivo.Methods: A novel biodegradable poly(ester amine) copolymer (PEA) was successfully prepared from low molecular weight polyethylenimine (PEI, 2000 Da) and poly(L-lactide) copolymers.Results: According to the results of agarose gel electrophoresis, particle size and zeta potential measurement, and transfection efficiency, the PEA copolymers showed a good ability to condense plasmid DNA effectively into nanocomplexes with a small particle size (≤150 nm) and moderate zeta potential (≥10 mV) at an appropriate polymeric carrier/DNA weight ratio. Compared with high molecular weight PEI (25kDa), the PEA obtained showed relatively high gene transfection efficiency as well as low cytotoxicity in vitro.Conclusion: These results indicate that such PEA might have potential application as a gene delivery system.Keywords: polyethylenimine, poly(L-lactide), gene delivery, cytotoxicity, transfection efficiency

Shuai Shi, Xiu Hong Wang, Gang Guo, Min Fan, Mei Juan Huang, Zhi Yong QianState Key Lab of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, PR ChinaAbstract: We prepared a series of microporous films based on poly(D,L-lactic acid) (PLA) via phase separation. According to scanning electron microscopy (SEM), a 3-dimensional foamy structure with multimicrometer scale pores on the air surface of film could be observed. As the morphology of PLA film could not be stabilized using solvent–nonsolvent phase separation, we investigated the effect of temperature, air movement, and concentration on the properties of microporous PLA films. The results show that when the temperature was 25°C in a vacuum, it was easy to prepare PLA film with micropores, and it was stable. As the relationship between the morphology and formation factors was clear and the morphology of the PLA film was controllable, we studied the PLA film’s potential use for cell culture. SEM results showed that NIH3T3 cell could be adhered on the surface of film well after incubation for 2 days. Meanwhile, in vitro culture experiments revealed the great biocompatibility of the scaffold for adsorption and proliferation of fibroblasts.Keywords: poly(D,L-lactic acid), scaffold, phase separation, cell culture

We have isolated a novel family of insect-selective neurotoxins that appear to be the most potent blockers of insect voltage-gated calcium channels reported to date. These toxins display exceptional phylogenetic specificity, with at least a 10,000-fold preference for insect versus vertebrate calcium channels. The structure of one of the toxins reveals a highly structured, disulfide-rich core and a structurally disordered C-terminal extension that is essential for channel blocking activity. Weak structural/functional homology with omega-agatoxin-IVA/B, the prototypic inhibitor of vertebrate P-type calcium channels, suggests that these two toxin families might share a similar mechanism of action despite their vastly different phylogenetic specificities.