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IMPORTANCE: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignant tumor, and durable disease control is rare with the current standard of care, even for patients who undergo surgical resection. OBJECTIVE: To assess whether neoadjuvant modified 5-fluorouracil, leucovorin, oxaliplatin, and irinotecan (mFOLFIRINOX) leads to early control of micrometastasis and improves survival. DESIGN, SETTING, AND PARTICIPANTS: This open-label, single-arm, phase 2 nonrandomized clinical trial for resectable PDAC was conducted at the Yale Smilow Cancer Hospital from April 3, 2014, to August 16, 2021. Pancreatic protocol computed tomography was performed at diagnosis to assess surgical candidacy. Data were analyzed from January to July 2023. INTERVENTIONS: Patients received 6 cycles of neoadjuvant mFOLFIRINOX before surgery and 6 cycles of adjuvant mFOLFIRINOX. Whole blood was collected and processed to stored plasma for analysis of circulating tumor DNA (ctDNA) levels. Tumors were evaluated for treatment response and keratin 17 (K17) expression. MAIN OUTCOMES AND MEASURES: The primary end point was 12-month progression-free survival (PFS) rate. Additional end points included overall survival (OS), ctDNA level, tumor molecular features, and K17 tumor levels. Survival curves were summarized using Kaplan-Meier estimator. RESULTS: Of 46 patients who received mFOLFIRINOX, 31 (67%) were male, and the median (range) age was 65 (46-80) years. A total of 37 (80%) completed 6 preoperative cycles and 33 (72%) underwent surgery. A total of 27 patients (59%) underwent resection per protocol (25 with R0 disease and 2 with R1 disease); metastatic or unresectable disease was identified in 6 patients during exploration. Ten patients underwent surgery off protocol. The 12-month PFS was 67% (90% CI, 56.9-100); the median PFS and OS were 16.6 months (95% CI, 13.3-40.6) and 37.2 months (95% CI, 17.5-not reached), respectively. Baseline ctDNA levels were detected in 16 of 22 patients (73%) and in 3 of 17 (18%) after 6 cycles of mFOLFIRINOX. Those with detectable ctDNA levels 4 weeks postresection had worse PFS (hazard ratio [HR], 34.0; 95% CI, 2.6-4758.6; P = .006) and OS (HR, 11.7; 95% CI, 1.5-129.9; P = .02) compared with those with undetectable levels. Patients with high K17 expression had nonsignificantly worse PFS (HR, 2.7; 95% CI, 0.7-10.9; P = .09) and OS (HR, 3.2; 95% CI, 0.8-13.6; P = .07). CONCLUSIONS AND RELEVANCE: This nonrandomized clinical trial met its primary end point, and perioperative mFOLFIRINOX warrants further evaluation in randomized clinical trials. Postoperative ctDNA positivity was strongly associated with recurrence. K17 and ctDNA are promising biomarkers that require additional validation in future prospective studies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02047474

Large-scale space membrane antennas have significant potential in satellite communication, space-based early warning, and Earth observation. Because of their large size and high flexibility, the dynamic analysis and control of membrane antenna are challenging. To maintain the working performance of the antenna, the pointing and surface accuracies must be strictly maintained. Therefore, the accurate dynamic modeling and effective active control of large-scale space membrane antennas have great theoretical significance and practical value, and have attracted considerable interest in recent years. This paper reviews the dynamics and active control of large-scale space membrane antennas. First, the development and status of large-scale space membrane antennas are summarized. Subsequently, the key problems in the dynamics and active control of large membrane antennas, including the dynamics of wrinkled membranes, large-amplitude nonlinear vibration, nonlinear model reduction, rigid-flexible-thermal coupling dynamic modeling, on-orbit modal parameter identification, active vibration control, and wave-based vibration control, are discussed in detail. Finally, the research outlook and future trends are presented.

PurposeProgrammed cell death-ligand 1 (PD-L1) as a cell surface glycoprotein can inhibit T cell function when binding to its receptor, PD-1. The newly developed therapy of targeting PD-1/PD-L1 signal pathway has shown great promise for the treatment of non-small cell lung cancer as well as melanoma. Approved by Food and Drug Administration, atezolizumab has become the first new drug to treat advanced bladder cancer. The aim of this study is to evaluate whether PD-L1 is associated with the lymphocytes infiltration in the tumour microenvironment and to assess the prognostic value of PD-L1 expression.Materials and methodsAmong 96 invasive bladder urothelial carcinomas, some were used to construct tissue-microarrays, and some cases with shallow infiltration or large heterogeneity were performed, respectively, for the following work. By means of immunohistochemistry and HE, PD-L1 expression and immune cell infiltration in the invasive front of urothelial carcinoma were analysed.ResultsWe find that PD-L1 expression in tumour cells and lymphocytes are significantly associated with more tumour infiltrating lymphocytes (TILs) and more T cells. The integrated TILs, T-PD-L1 and I-PD-L1 are not significantly correlated with the overall survival (OS) of patients. However, the combination of T-PD-L1 and TILs, T-PD-L1 and I-PD-L1 is significantly correlated with the OS of patients. The T-PD-L1 (−)/TIL (−) group show the best prognosis and the T-PD-L1 (+)/I-PD-L1 (−) group show the worst prognosis. Furthermore, a multivariate analysis reveal that PD-L1 expression of lymphocytes is an independent prognostic factor for OS of patients.ConclusionsOur study reveal that PD-L1 of tumour cells are associated with the corresponding T cells infiltration and that the combination of T-PD-L1 and I-PD-L1, T-PD-L1 and TILs could be a relevant marker for the determination of the prognostic role of patients with the urothelial carcinoma.

In this paper, on-orbit modal identification of membrane antenna spacecraft is investigated. Based on the modal identification results, dynamic model of the spacecraft is updated, and a vibration controller is designed. First of all, the rigid-flexible coupling dynamic model of the membrane antenna spacecraft is established by using Lagrange equation. Then, the covariance driven stochastic subspace identification (SSI-COV) method, which only relies on output measurements of the system under ambient excitation, is adopted to identify the modal parameters. By using the modal identification results, the model updating is performed based on sensitivity analysis, and vibration controller is designed to suppress the vibration caused by attitude maneuver based on the component synthesis vibration suppression (CSVS) method. Simulation results show that the SSI-COV method can identify the modal parameters of the membrane antenna spacecraft effectively, the updated dynamic model produces obvious improvements over the original model, and the vibration suppression effect of the CSVS controller is improved significantly after model updating.

With the development of the observation technology and the improvement of resolution requirements, a new membrane diffraction large space telescope is proposed to realize real-time high-resolution earth observation. Due to its light weight, high optical imaging accuracy and large folding ratio, the membrane diffraction space telescope has an extensive development prospect. Vibration of the large space truss inevitably occurs in the space environment. Such vibration will last continuously, influencing normal earth imaging of the space telescope. Thus, it is necessary to adopt an appropriate control method to suppress structural vibration. Considering the great structural degree of freedom, the equivalent dynamic model of the space telescope is established to simplify the vibration controller design in this paper. First, the truss lattice is equivalent to a micro-polar beam based on the energy-equivalence principle, and then the equivalent dynamic model of the telescope structure is built with Finite Element Method. Second, the linear quadratic regulator is adopted to design a vibration active controller on the basis of the equivalent dynamic model. Next, through proper transformations, the transformed active controller is used to control the vibration of the original space telescope structure. Finally, the correction of the equivalent dynamic model and the validity of the proposed active control strategy are verified by numerical simulations. The simulation results demonstrate the designed active controller in this paper could effectively suppress the vibration of the space telescope.

Membrane solar array has attracted a lot of attentions in recent years because of the advantage of light-weight, low-cost, and high-folding-ratio. Meanwhile, the membrane solar array structure also pose challenging large-amplitude vibration issue which will impact the performance of the spacecraft significantly. In this paper, active nonlinear vibration control of a membrane solar array structure is studied. Based on the nonlinear finite element method, a nonlinear dynamic model of the structure is established. The optimal positions of piezoelectric actuators are determined by optimizing a controllability optimization criterion with Particle Swarm Optimizer algorithm. An active controller is designed to suppress the undesired nonlinear vibration based on the linearized dynamic model by using the LQR control method. Simulation results show that the designed active controller can suppress the nonlinear vibration of the membrane solar array structure effectively, and the optimally placed actuators can produce better control effect with smaller control inputs.

Space robots are playing an increasingly important role in on-orbit services. Affected by the coupling of dynamics, the base attitude of a space robot will deflect with the motion of its manipulators, which leads to unfavorable effect to the success of the mission. The trajectory planning problem for base attitude disturbance minimization of a dual-arm space robot will be studied in this article. Along the planned trajectory, the attitude of the base will keep unchanged when the end effectors of the manipulators arrive at the desired position. First, the dynamic equation of the dual-arm space robot is given, and the direct-inverse mixed dynamic equation is also derived. Then, the rotation trajectory of the manipulator joints is parameterized, and the attitude deflection of the base with respect to the given parameters is calculated based on the direct-inverse mixed dynamic equation. The particle swarm optimization algorithm is utilized to obtain the optimal trajectory. Finally, numerical simulations are carried out to verify the effectiveness of the method proposed in this article. Four cases are included, considering symmetrical or asymmetrical initial configuration and synchronous or asynchronous start of the dual arms. The simulation results show that, in each case, the method proposed can effectively plan the trajectory along which the base attitude will keep nearly unchanged before and after the motion of the dual arms.

In recent years, the sustained growth of space launch missions has inevitably led to a rapid increase in space debris, which has attracted extensive attention to the capture and removal of space debris. This paper presents a new strategy for detumbling a flexible tumbling target in the post-capture phase using a flexible-base space robot (also called a chaser), which involves trajectory optimization and composite control of the chaser. Based on the dynamic equation of the combined system, the trajectories of the chaser base and the manipulator’s joints are parameterized by quintic polynomial curves, and then are simultaneously optimized for the collision avoidance of the combined system and the reduction of panel deformation, control energy, and mission duration. The Pareto-optimal solutions of the optimization problem are obtained by the multi-objective particle swarm optimization (MOPSO) algorithm. The composite control scheme, composed of a trajectory tracking controller and a vibration suppression controller, is used for the chaser to detumble the target along the planned trajectories, stabilize its base attitude, and eliminate the residual vibration of the flexible panels. Two representative cases are used to verify the effectiveness and robustness of the proposed detumbling strategy for the target with parameter uncertainties.

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, which lacks effective therapies. Here, we demonstrate that the transcription factor, homeobox C6 (HOXC6), is overexpressed in most PDACs, and its inhibition blocks PDAC tumor growth and metastasis. HOXC6 transcriptionally activates tumor-promoting kinase MSK1 and suppresses tumor-inhibitory protein PPP2R2B in PDAC. HOXC6-induced PPP2R2B suppression causes mammalian target of rapamycin (mTOR) pathway activation, which facilitates PDAC growth. Also, MSK1 upregulation by HOXC6 is necessary for PDAC growth because of its ability to suppress apoptosis via its substrate DDX17. Combinatorial pharmacological inhibition of MSK1 and mTOR potently suppressed PDAC tumor growth and metastasis in PDAC mouse models. PDAC cells with acquired resistance to MSK1/mTOR-inhibitors displayed activated insulin-like growth factor 1 receptor (IGF1R) signaling and were successfully eradicated by IGF1R inhibitor. Furthermore, MEK inhibitor trametinib enhanced the efficacy of dual MSK1 and mTOR inhibition. Collectively, these results identify therapeutic vulnerabilities of PDAC and an approach to overcome acquired drug resistance to prolong therapeutic benefit.

In this paper, the active control of nonlinear vibration of a membrane antenna structure is investigated. Considering the geometric nonlinearity of large amplitude vibration of the membrane, the von Karman type geometrical nonlinear strain–displacement relationship is employed in this paper. Then, a nonlinear dynamic model of the membrane antenna structure is established by using the finite element method. It is assumed that the amplitude of vibration of the structure is relatively small when the controller in on, and then a H∞robust controller is developed to control the undesired nonlinear vibration of the membrane antenna structure based on the linearized model of the structure. Active control of both the free vibration and forced vibration of the structure are investigated. Numerical simulations are presented to study the nonlinearity of the large amplitude vibration of the structure and the effectiveness of the presented controller.

Many control laws, such as optimal controller and classical controller, have seen their applications to suppressing the aeroelastic vibrations of the aeroelastic system. However, those control laws may not work effectively if the aeroelastic system involves actuator faults. In the current study for wing flutter of reentry vehicle, the effect of actuator faults on wing flutter system is rarely considered and few of the fault-tolerant control problems are taken into account. In this paper, we use the radial basis function neural network and the finite-time H∞adaptive fault-tolerant control technique to deal with the flutter problem of wings, which is affected by actuator faults, actuator saturation, parameter uncertainties and external disturbances. The theory of this article includes the modeling of wing flutter and fault-tolerant controller design. The stability of the finite-time adaptive fault-tolerant controller is theoretically proved. Simulation results indicate that the designed fault-tolerant flutter controller can effectively deal with the faults in the flutter system and can promptly suppress the wing flutter as well.

In this paper, deployment dynamics of large-scale flexible solar arrays are investigated. The adopted solar array system is introduced first, including system configuration, the tension control mechanism (TCM), guy-wire and joint damper between sub-panels. Then kinematic description of a single flexible body and kinematic constraint equations of two bodies are deduced. Finally, dynamic equation of the solar array system is established by the Jourdain velocity variation principle. The validity of the dynamic model is verified through comparison with ADAMS software. The effects of guy-wire, TCM and joint damper on the system performance are studied in detail. Simulation results indicate that the proposed model is effective to describe the deployment dynamics of the large-scale flexible solar arrays, and that guy-wire, TCM and joint damper have marked influence on the dynamic behaviour of deployment of the solar array system.

Autoimmune pancreatitis (AIP) is an inflammatory process that has characteristic clinical, radiographic, and pathologic features but may mimic pancreatic malignancy. In this study, we reviewed our experience in the endoscopic ultrasound-guided fine-needle aspiration evaluation of pancreatic lesions in patients with AIP.

Rapid on-site evaluation (ROSE) has repeatedly been shown to improve diagnostic performance of endoscopic ultrasound–guided fine-needle aspiration of pancreatic lesions. However, the practice of providing ROSE service varies among institutions. ROSE helps to ensure adequate sampling, appropriate specimen triage, and timely patient management. In this review, we discuss the practice and clinical significance of ROSE, the factors influencing the ROSE diagnosis, the financial considerations for providing ROSE service, and pitfalls to render a ROSE diagnosis.

The myosin-II heavy chain Myo1 and the formin Bni1 mediate the targeting of the myosin essential light chain Mlc1 to the division site before and during cytokinesis, respectively, in the budding yeast Saccharomyces cerevisiae.

Patients with EGFR-mutant lung adenocarcinomas (LUADs) who initially respond to first-generation tyrosine kinase inhibitors (TKIs) develop resistance to these drugs. A combination of the irreversible TKI afatinib and the EGFR antibody cetuximab can be used to overcome resistance to first-generation TKIs; however, resistance to this drug combination eventually emerges. We identified activation of the mTORC1 signaling pathway as a mechanism of resistance to dual inhibition of EGFR in mouse models. The addition of rapamycin reversed resistance in vivo. Analysis of afatinib-plus-cetuximab-resistant biopsy specimens revealed the presence of genomic alterations in genes that modulate mTORC1 signaling, including NF2and TSC1. These findings pinpoint enhanced mTORC1 activation as a mechanism of resistance to afatinib plus cetuximab and identify genomic mechanisms that lead to activation of this pathway, revealing a potential therapeutic strategy for treating patients with resistance to these drugs.

BACKGROUND:In the fineneedle aspiration biopsy FNAB diagnosis of Bcell nonHodgkin lymphomas BNHL, the role of flow cytometry FC can be limited because of nondiagnostic findings. Fluorescence in situ hybridization FISH studies, similar to FC, can be helpful in establishing clonality and in subclassifying the lymphoma. The aim of the current study was to determine whether FISH studies performed on unstained direct smears improved the ability to diagnose andor subclassify BNHL on FNAB.METHODS:A total of 181 cases of BNHL diagnosed by FNAB were retrieved. The cytomorphology, ancillary study results, clinical information, and available pathologic followup were reviewed.RESULTS:Of the 181 cases, FISH studies were performed in 106 cases 59. The indications for FISH studies were for subclassification 59 cases; 56 and nondiagnostic or unavailable FC results 47 cases; 44. Of the 59 cases submitted for subclassification, 23 cases 39 were successfully subclassified. The 47 cases with nondiagnostic or unavailable FC results included cases in which FC demonstrated a surface immunoglobulinnegative population 19 cases; 40, had insufficient cellularity 18 cases; 38, yielded negative results 6 cases; 13, or had no specimen submitted 4 cases; 9. In this group, 26 cases 55 demonstrated an immunoglobulin heavychain gene rearrangement andor chromosomal translocation.CONCLUSIONS:The results of the current study illustrate that FISH studies performed on unstained direct smears play a complementary role to FC in establishing the diagnosis andor subclassification of BNHL. Thus, the preparation of unstained smears at the time of FNAB can be helpful for potential FISH studies. Cancer Cancer Cytopathol 2009. © 2009 American Cancer Society.

Active control of a flexible cantilever plate with multiple time delays is investigated using the discrete optimal control method. A controller with multiple time delays is presented. In this controller, time delay effect is incorporated in the mathematical model of the dynamic system throughout the control design and no approximations and assumptions are made in the controller derivation, so the system stability is easily guaranteed. Furthermore, this controller is available for both small time delays and large time delays. The feasibility and efficiency of the proposed controller are verified through numerical simulations in the end of this paper.

Active control of a flexible cantilever plate with multiple time delays is investigated using the discrete optimal control method. A controller with multiple time delays is presented. In this controller, time delay effect is incorporated in the mathematical model of the dynamic system throughout the control design and no approximations and assumptions are made in the controller derivation, so the system stability is easily guaranteed. Furthermore, this controller is available for both small time delays and large time delays. The feasibility and efficiency of the proposed controller are verified through numerical simulations in the end of this paper.

In this study, we investigated hypolipidemic mechanisms of the ethanolic extract of Ananas comosusL. leaves (AC) in mice and then determined its activities in related enzymes. The results showed that AC (0.40 g/kg) significantly inhibited the increase in serum triglycerides by 40% in fructose-fed mice. In mice induced by alloxan and high-fat diets, serum total cholesterol remained at a high level (180 – 220 mg/dl) within 7 days of removing high-fat diets but reached normal level (120 – 140 mg/dl) after AC (0.40 g/kg per day) treatment. Also, AC (0.40 and 0.80 g/kg) significantly inhibited serum lipids from the increase in Triton WR-1339-induced hyperlipidemic mice. AC (0.01 – 100 µg/ml) selectively activated lipoprotein lipase (LPL) activity by 200% – 400% and significantly inhibited 3-hydroxyl-methyl glutaryl coenzyme A (HMGCoA) reductase activity by 20% – 49% in vitro. Furthermore, 2 months of fenofibrate (0.20 g/kg) administration particularly increased mice liver weights (0.0760 ± 0.0110 g/g) while AC (0.40 g/kg) had no effect (0.0403 ± 0.0047). Taken together, these results suggest that AC will be a new potential natural product for the treatment of hyperlipidemia that exerts its actions through mechanisms of inhibiting HMGCoA reductase and activating LPL activities. Its action mechanisms differentiate from those with fibrates but may be partly similar to those with statins. It is hopeful that AC may serve as the adjuvant for fibrates.

The discrete-time variable structure control method for seismically excited linear structures with time delay in control is investigated in this paper. The control system with time delay is first discretized and transformed into standard discrete form which contains no time delay in terms of the time delay being integer and non-integer times of sampling period, respectively. Then the discrete switching surface is determined using ideal quasi-sliding mode and discrete controller is designed using the discrete approach-law reaching condition. The deduced controller and switching surface contain not only the current step of state feedback but also linear combination of some former steps of controls. Numerical simulations are illustrated to verify the feasibility and robustness of the proposed control method. Since time-delay effect is incorporated in the mathematical model for the structural control system throughout the derivation of the proposed algorithm, system performance and dynamic stability are guaranteed. Copyright © 2002 John Wiley & Sons, Ltd.

A tetra-component blend, consisting of low-density polyethylene (LDPE), polyvinyl chloride (PVC), polypropylene (PP), and polystyrene (PS), was studied as a model system of commingled plastic wastes (LDPE/PVC/PP/PS, mass ratio: 70/10/10/10). Effects of chlorinated polyethylene (CPE), ethylene–propylene–diene monomer (EPDM), styrene–butadiene–styrene (SBS), and their mixture (CPE/EPDM/SBS, mass ratio: 2/2/2) on the mechanical properties and morphology of the system were investigated. With addition of several elastomers and their mixture, the tensile strength of the blends decreased slightly, although both the elongation at break and the impact strength increased. Among these elastomers, EPDM exhibited the most significant impact modification effect for the tetra-component blends. SBS and the mixture have a good phase-dispersion effect for the tetra-component blend. By adding a crosslinking agent [dicumyl peroxide (DCP)], the mechanical properties of the tetra-component blends also increased. When either SBS or the mixture was added to the blend together with DCP, the probability that the crosslinking agent (DCP) would be at the interface improved because of the phase-dispersion effect of SBS. Therefore, more co-crosslinked products will form between LDPE and other components. Accordingly, remarkable improvement of the interfacial adhesion and hence the mechanical properties of the tetra-component blends occurred. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2947–2952, 2001

To determine the effects of ischemia-reperfusion (I/R) on α1-adrenergic-receptor (α1-AR) functions, α1-AR-mediated contraction, inositol phosphate (IP) accumulation, and α1-AR-G protein coupling were examined in the tail arteries of anesthetized rats after 60 min of ischemia and 60 min of reperfusion. The contractile response to norepinephrine (NE) was significantly increased after I/R, whereas the contractile response to KCl remained unchanged. This was accompanied by a 69% increase in NE-stimulated IP accumulation. Furthermore, receptor-stimulated coupling of α1a-AR to Gαq/11proteins was increased, whereas the coupling of α1b-AR or α1d-AR to their G proteins was not altered by I/R. These changes in vascular α1-AR function occurred without concurrent alteration in expression levels of membrane α1-AR subtypes or in the associated G proteins. These data demonstrate that I/R increases α1a-AR-Gq/11protein coupling and α1-AR-stimulated IP accumulation in the tail artery. The alterations in α1-AR signaling are associated with and may underlie the enhanced contractile response of the tail artery to adrenergic stimulation after I/R.

Poly[1,1-bis(trimethylsilyloxy)-3,3,5,5-tetramethyltrisiloxane], the first linear polysiloxane in which each third silicon atom of the polymer backbone is a tetra-functional SiO2 (Q) unit, has been prepared by anionic ring-opening polymerization of 1,1-bis(trimethylsilyloxy)-3,3,5,5-tetramethylcyclotrisiloxane.

In this study we introduce a novel in vitro'oil-drop' assay system for the measurement of endothelial cell (EC) migration, based on the original concept of the Teflon fence assay (Pratt et al., 1984; Am. J. Pathol. 117: 349–354). An aliquot of 15–20,000 human umbilical vein EC (HUVEC) is pipetted through a layer of mineral oil. The cells readily attach, spread and migrate on the surface of a matrix-coated tissue culture dish as a confluent circular monolayer. Migration is measured as the net increase in the total area covered at 24 hours. We have used this system to quantify EC migration on matrices composed of a mixture of type I collagen and either von Willebrand factor (vWF) or fibronectin (FN) in the presence or absence of tumor necrosis factor α (TNFα). Plating efficiency on both vWF/collagen and FN/collagen, measured by counting cells after attachment and spreading, is about 80%. With this method, migration on vWF/collagen was about 6.4 mm2and 5.3 mm2for TNFα-treated and untreated HUVEC, respectively. HUVEC migration on FN/collagen was slightly greater – 6.4 mm2and 6.5 mm2with and without TNFα treatment, respectively. During the 24 hour time period, HUVEC numbers increased 30–40% on vWF/collagen, and 60–80% on FN/collagen, with increased proliferation observed with TNF-α treatment. EC proliferation could be completely inhibited by 2 mM hydroxyurea. This assay system has proven useful in our studies to quantify cell migration and proliferation.

Motion prediction of space noncooperative target is an important issue for spacecraft on-orbit service. After obtaining high-precision motion prediction results, the chaser can efficiently plan a motion trajectory to approach the target and then capture it. In this paper, a motion prediction method considering J2 perturbation is proposed for a free-floating noncooperative target. The core idea of this method is to identify dynamic parameters of the target, and then realize the motion prediction through a dynamic model of the target that considering J2 perturbation. In the identification of the dynamic parameters, inertia parameters of the target are preliminarily identified first, then a noise-adaptive unscented Kalman filter (UKF) is applied to roughly identify the dynamic parameters, and finally, the identification precision is further improved through optimization. At the end of this paper, the significance of considering J2 perturbation is demonstrated by numerical simulations, and the effectiveness of the proposed method is verified. Simulation results indicate that J2 perturbation has a great influence on the motion prediction of the target and that the proposed method can yield long-time high-precision motion prediction results. Specifically, under the simulation conditions of this paper, the predicted time obtained by the proposed method is longer than 200 s, and the errors of the motion prediction results of the target's attitude and position are less than 2 deg and 0.02 m, respectively.

The effects of repeated cocaine administration on contractile responses were studied in adult rabbits. Repeated cocaine exposure caused a significant increase in the maximal response of the aorta to the agonists norepinephrine and serotonin as well as the receptor-independent stimulus KCI when compared to the saline controls. Cocaine exposure caused a significant increase in the wet weights of both the heart and aorta. When the contraction was normalized to the wet weight of the aorta there was no difference between rabbits administered cocaine and saline. Acute cocaine administration caused a time-dependent increase in immunoreactivity of the proto-oncogene c-Fos in the aorta. These results show that repeated cocaine administration leads to the development of cardiovascular hypertrophy.

It is known that serum is a most important factor supporting cell survival and growth. Particularly, the deprivation of serum would result in the death of human endothelial cell. Our previous paper reported an endothelial cell-viability maintaining factor (EC-VMFa) purified from fetal bovine serum and identified as an apolipoprotein. In the present further study, it is demonstrated that another potent serum factor (refer as EC-VMFb) is also possessed of the endothelial cell-viability maintaining activity, improving a long-term survival of human endothelial cells in serum-free medium. EC-VMFb has a molecular weight of 66,000 (reduced and nonreduced), pIof 4.5 and has been identified as fragment b of complement factor B (Bb)-like protein by amino-terminal amino acid sequence.