bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective Random Field Characterization Considering Statistical Dependence for Probability Analysis and Design
Authors: Xi Zhimin , Youn Byeng D. , Hu Chao
Published: March 2011

The Proper Orthogonal Decomposition (POD) method has been employed to extract the important signatures of the random field presented in an engineering product or process. Our preliminary study found that coefficients of the signatures are statistically uncorrelated but may be dependent. In general, the statistical dependence of the coefficients is ignored in the random field characterization for probability analysis and design. This paper thus proposes an effective approach to characterize the random field for probability analysis and design while accounting for the statistical dependence among the coefficients. The proposed approach is composed of two technical contributions. The first contribution is to develop a generic approximation scheme of random field as a function of the most important field signatures while preserving prescribed approximation accuracy. The coefficients of the signatures can be modeled as random field variables and their statistical properties are identified using the Chi-Square goodness-of-fit test. Second, the Rosenblatt transformation is employed to transform the statistically dependent random field variables into statistically independent random field variables. There exist so many transformation sequences when the number of random field variables becomes large. It was found that an improper selection of a transformation sequence may introduce high nonlinearity into system responses, which causes inaccuracy in probability analysis and design. Hence, a novel procedure is proposed for determining an optimal transformation sequence that introduces the least degree of nonlinearity to the system response after the Rosenblatt transformation. The proposed random field characterization can be integrated with one of the advanced probability analysis methods, such as the Eigenvector Dimension Reduction (EDR) method, Polynomial Chaos Expansion (PCE) method, etc. Three structural examples including a Micro-Electro-Mechanical Systems (MEMS) bistable mechanism are used to demonstrate the effectiveness of the proposed approach. The results show that the statistical dependence in random field characterization cannot be neglected for probability analysis and design. Moreover, it is shown that the proposed random field approach is very accurate and efficient.
Modeling the Compliance of a Variable Stiffness C-Shaped Leg Using Castigliano’s Theorem
Authors: Aydın Yasemin O¨. , Galloway Kevin C. , Yazicioglu Yigit , Koditschek Daniel E.
Published: March 2011

This paper discusses the application of Castigliano’s Theorem to a half circular beam intended for use as a shaped, tunable, passively compliant robot leg. We present closed-form equations characterizing the deflection behavior of the beam (whose compliance properties vary along the leg) under appropriate loads. We compare the accuracy of this analytical representation to that of a Pseudo Rigid Body (PRB) approximation in predicting the data obtained by measuring the deflection of a physical half-circular beam under the application of known static loads. We briefly discuss the further application of the new model for solving the dynamic equations of a hexapod robot with a C-shaped leg.
A New Life Prediction Model Based on Ductility Exhaustion Theory for High Temperature Low Cycle Fatigue of Turbine Disk Alloys
Authors: Zhu Shun-Peng , Sun Rui , Huang Hong-Zhong , Zuo Ming J.
Published: March 2011

Based on ductility exhaustion theory and the generalized damage parameter, a new viscosity-based life prediction model is put forward to account for creep and mean strain or stress effects in a low cycle fatigue regime. The mechanisms of loading waveform and cyclic hardening effects are also taken into account within this model. It assumes that damage accrues by means of viscous flow and ductility consumption relates only to plastic strain and creep strain under high temperature low cycle fatigue conditions. The proposed model provides a better prediction on the fatigue behaviors of Superalloy GH4133 than the Goswami’s ductility model and the generalized damage parameter. Compared with the proposed model and the generalized damage parameter, the Goswami’s model cannot properly account for creep and mean stress effects on the low cycle fatigue life. Under non-zero mean strain conditions, the proposed model provides more accurate predictions of GH4133 Superalloy than that with zero mean strains.
Damping Reduction in Structures Using Piezoelectric Circuitry With Negative Resistance
Authors: Zhao J. , Wang X. , Tang J.
Published: March 2011

As damping reduction can potentially lead to performance enhancement in certain applications, a scheme based upon the concept of piezoelectric circuitry that yields reduced damping effect in a structural system is developed. The piezoelectric circuitry consists of an inductor and a negative resistance circuit serially connected to the piezoelectric transducer. By using the negative resistance element to make the overall resistance of the circuitry to be negative, the vibratory response becomes higher. The stability boundary of the negative resistance is derived for both ideal piezoelectric transducer and actual transducer with energy loss. The results are validated via experimental investigations.
An Energy Harvester With Bistable Compliance Characteristics
Authors: Cammarano Andrea , Burrow Stephen G. , Barton David A. W.
Published: March 2011

In this paper we present a bistable energy harvesting device. The bi-stability is produced by the particular arrangement of the permanent magnets which form the electro-magnetic transduction mechanism, in conjunction with an iron-cored stator. The harvester features a high magnetic loading but the resulting bistable compliance introduces complex dynamic behaviors. An experimental approach is first used to characterize the device, from which a simplified mathematical model has been developed. The model is then validated by comparison with experimental data. It has been shown that both chaotic and periodic responses are possible. The paper explores the dynamic behavior of the bistable system and attempts to understand the trade-off between the complex mechanical behavior and the benefits of increased magnetic loading.
Input of Log-Aesthetic Curves by Use of Control Points: Plugging an LA Curve Module in a Commercial Geometric Modeler
Authors: Shirahata Ryo , Agari Shin’ichi , Miura Kenjiro T.
Published: March 2011

In the field of industrial design, the aesthetic design is an important element to determine the quality of products and it is inevitable for them to make it aesthetic and attractive to improve the total quality of the shape design. If we can find an equation of aesthetic curves, it is expected that the quality of the curve design improves drastically because we can use it as a standard to generate, evaluate, and deform the curves. The log-aesthetic curve was proposed to generate high-quality curves efficiently [6]. Harada et al. insist that natural aesthetic curves like birds’ eggs and butterflies’ wings as well as artificial ones like Japanese swords and key lines of automobiles have such a property that their logarithmic curvature histograms (LCHs) can be approximated by straight lines and there is a strong correlation between the slopes of the lines and the impressions of the curves. Miura et al. defined the LCH analytically with the aim of approximating it by a straight line and propose new expressions to represent an aesthetic curve whose LCH is given exactly by a straight line. Furthermore they derive general formulas of aesthetic curves that describe the relationship between their radiuses of curvature and lengths. Also they defined the self-affinity possessed by the curves satisfying the general equations of aesthetic curves. The proposed curve is called the log-aesthetic curve. Agari et al. [1] proposed a method to input compound-rhythm log-aesthetic curves by use of four control points. Yoshida and Saito [2] proposed a method to generate log-aesthetic curves using three control points by searching for one variable, although Agari’s method searches for two variables. In this paper we compare Agari’s method with Yoshida-Saito’s method, and check out whether both of them generate the same curve. Next, we propose an efficient method to input log-aesthetic curve segments with an inflection point. Furthermore we try to improve the quality and the efficiency of the aesthetic design by plugging an log-aesthetic curve module in a commercial geometric modeler “FullMoon”.
Design of Zero-Emissions Vehicles by Multidisciplinary Student Teams in Multi-Years: A Model for Engineering Design Education
Authors: Hsu Tai-Ran , Yee Raymond K. , Le Thuy T.
Published: March 2011

This paper presents a unique experience in educating students from mechanical and electrical engineering majors in a course on senior design projects involving the design and production of two proof-of-concept electric vehicles, the mini-ZEM and ZEM (stands for Zero EMissions) vehicles. The ZEM vehicles combined positive aspects and latest technologies in electric vehicle design, solar/electric power conversions, and ergonomic human power into one affordable and environmentally sustainable vehicle for urban transportation. The 55 mechanical and 10 electrical engineering majors plus 7 students from business participated in this multidisciplinary project spanned over three academic years. The students involved in this multi-year endeavor gained valuable experiences in real-world working environment with multifunctional and multi-year subgroups. The success of this new attempt in conducting senior design projects classes have set a model for faculty members in the authors’ university in conducting similar courses.
Nanosecond pulsed field emission from single-gate metallic field emitter arrays fabricated by molding
Authors: Tsujino S. , Paraliev M. , Kirk E. , Vogel T. , Le Pimpec F. , Gough C. , Ivkovic S. , Braun H.-H.
Published: March 2011

Electrically gated pulsed field emission from molybdenum field emitter arrays was studied. Single-gate field emitter array devices supported by metallic substrates were fabricated by a combination of molding and a self-aligned gate process. Devices were tested in a low-inductance cathode holder compatible with the high-acceleration electric field of a pulsed diode gun. Pulsed field emission down to 1.1 ns was observed for single-gate devices with 1.2×103–1.2×105 emitter tips with 5 μm array pitches. Integrating the field emitter arrays in a high-voltage pulsed diode gun, the authors demonstrated nanosecond field emission at an acceleration field of 30 MV/m at the cathode surface and acceleration of the field emission electron beam up to 300 keV. In addition, transverse beam emittance of the single-gate devices was measured with two different array sizes.
Accrual to Cancer Clinical Trials in the Era of Molecular Medicine
Authors: Schilsky Richard L.
Published: March 2011

In the testing of targeted cancer therapies, new issues can complicate the decision by patients or providers to participate in clinical trials.
A National Cancer Clinical Trials System for Targeted Therapies
Authors: Mendelsohn John
Published: March 2011

Clinical cancer research requires a well-supported and efficient national clinical trials network that engages in innovative trials of modern cancer therapies.
Strike Three: Positive Progress on the Triple Negative
Authors: Gesty-Palmer Diane
Published: March 2011

Triple-negative breast cancers are driven by—surprise!—a tumor suppressor that regulates protein tyrosine kinases.
The Hunt for Red October
Authors: Tridandapani Srini
Published: March 2011

Investigators have improved medical sonar (ultrasound) to hunt down and track elusive cancer cells.
Expression of CK19 in invasive breast carcinomas of special histological types: implications for the use of one-step nucleic acid amplification
Authors: Alvarenga César A , Paravidino Paula I , Alvarenga Marcelo , Dufloth Rozany , Gomes Madalena , Zeferino Luiz C , Schmitt Fernando
Published: March 2011

Background

The sentinel lymph node (SLN) is the first lymph node to receive the lymphatic drainage of a primary tumour; based on the knowledge that CK19 is positive in more than 95% of breast carcinomas, a molecular method for intraoperative diagnosis of SLN metastases (the one-step nucleic acid amplification (OSNA) assay) was developed.

Aims

To evaluate CK19 immunoreactivity in a series of special histological types of breast carcinoma in order to verify whether the OSNA assay can be used in all breast cancer cases independently of the histological type.

Methods

116 samples of invasive breast carcinomas of special type were investigated for CK19 immunoreactivity in tissue microarrays (TMA); negative cases were evaluated in the entire tissue tumour tissue.

Results

Of the 116 cases, 88.9% were positive CK19. Micropapillary and apocrine carcinomas were all positive for CK19 in TMAs. The tubular (93%), mucinous (86%), medullary typical and atypical (84%), mixed carcinomas (83%) increased the rate of positivity for this marker to 100% after repeating the immunostain in whole tissue of negative TMA cases, because the expression of those cases was focal.

Conclusion

Most breast cancer cases were positive for CK19, independent of the histological type; therefore the OSNA assay can be used in all breast cancer cases with a potential low rate of false negative for CK19 detection of micrometastasis. There is an important variation between the positivity assessed on TMAs and the entire tissue; these findings can be clinically relevant because in some cases CK19 is evaluated on core-needle biopsy prior to surgery.
Medicare physician payment rules for 2011: a primer for the neurointerventionalist: Figure 1
Authors: Manchikanti Laxmaiah , Hirsch Joshua A
Published: March 2011

Physicians generally have been affected by significant changes in the patterns of medical practice evolving over the past several decades. The Patient Protection and Affordable Care Act of 2010, also called ACA for short, impacts physician professional practice dramatically. Physicians are paid in the USA for their personal services. The payment system is highly variable in the private insurance market; however, governmental systems have a formula based payment, mostly based on the Medicare payment system. Physician services are billed under part B. The Neurointerventional practice is typically performed in a hospital setting. The VA system is a frequently cited successful implementation of a government supported health care program. Availability of neurointerventional services at many VA medical centers is limited. Since the inception of the Medicare program in 1965, several methods have been used to determine the amounts paid to physicians for each covered service. Initially, the payment systems compensated physicians on the basis of their charges. In 1975, just over 10 years after the inception of the Medicare program, payments changed so as not to exceed the increase in medical economic index. The involvement of medical economic index failed to curb increases in costs, leading to the determination of a yearly change in fees by legislation from 1984 to 1991. In 1992, the fee schedule essentially replaced the prior payment system that was based on the physician's charges, which also failed to curb the growth in spending. Thus, in 1998, the sustainable growth rate system was introduced. In 2009, multiple unsuccessful attempts were made by Congress to repeal the formula. The mechanism of the sustainable growth rate includes three components that are incorporated into a statutory formula: expenditure targets, growth rate period and annual adjustments of payment rates for physician services.
A PRODUCT FORM SOLUTION FOR TREE NETWORKS WITH DIVISIBLE LOADS
Authors: ROBERTAZZI THOMAS G.
Published: March 2011

A product form solution for the optimal fractions of divisible load to distribute to processors in a multi-level tree network is described. Here optimality involves parallel processing the load in a minimal amount of time. This tractable solution is similar to the product form solution for equilibrium state probabilities arising in Markovian queueing networks. The existence of this product form solution answers a long standing open question for divisible load scheduling.
SEARCHING FOR PSEUDO-INVARIANT EIGEN-OPERATOR OF THE ∧-TYPE THREE-LEVEL JAYNES–CUMMINGS MODEL
Authors: YUAN HONG-CHUN , FAN HONG-YI , LI HENG-MEI , XU XUE-XIANG
Published: March 2011

We utilize pseudo-invariant eigen-operator (PIEO) method to research the three-level Jaynes–Cummings (JC) model. Our main task is to simplify the JC model and then redescribe the Hamiltonian via supersymmetric transformation generators. Another is to search for the so-called PIEO in terms of supersymmetric generators, which directly leads to the energy-level gap for the above system. We believe that this new approach may be extended to deal with more other generalized JC models.
THE DAUNS–HOFMANN THEOREM REVISITED
Authors: HOFMANN KARL HEINRICH
Published: March 2011

John Dauns died on June 4, 2009 of cancer in New Orleans at the age of 73. His work on rings and modules is well-known in the algebra community. However, functional analysts working in the area of C*-algebras are likely to know his name from one theorem that is a corollary of results he and I had obtained in work we did in the mid-sixties of the last century ([17, 27, 18]) and which became known as the Dauns-Hofmann Theorem in C*-algebra theory. It has been known in the C*-text book and monograph literature up to the recent one under this name ([9, 20, 21, 39, 41]) since it provides apparently a useful tool that continues to be used in current research (see e.g. [7, 8, 25, 38, 40]). The problem with the historical record of the Dauns–Hofmann Theorem is that it used to be somewhat obscure how it originated and that the full weight of what was proved was not precisely understood for a long time. As John Dauns was deeply, if not subbornly involved in the development of the early phases of the representation of rings, algebras, C*-algebras (and other classes of algebras) by continuous sections in bundles (sometimes called continuous fields) [11–18], and since his work in this area was substantial and contributed much to a local culture of "sectional representation" at Tulane University ([19, 22, 27–34, 43, 44, 48]), I feel that it is justified to attempt a clarification. He can no longer participate himself in such an attempt; nor would he actually protest the occasional lack of acknowledgment were he alive, because that would be contrary to his ever gentle disposition. This small survey is devoted to shedding some additional light on this portion of John Dauns' work in mathematics; it is natural that it should have a personal tenor by a writer remembering his presence and his work as a collaborator.
PERFECT TELEPORTATION, SUPERDENSE CODING VIA A KIND OF W-CLASS STATE
Authors: SHANG-GUAN LI-YING , SUN HONG-XIANG , CHEN XIU-BO , JIA HENG-YUE , WEN QIAO-YAN , ZHU FU-CHEN
Published: March 2011

Perfect teleportation and superdense coding are discussed via a special kind of W-state. It is shown that the state can be used for perfect teleportation of the state x|0〉⊗N + y|1〉⊗N. And the state can be utilized for superdense coding. Moreover, it is demonstrated that the sender can transmit N classical bits to the receiver by sending N − 1 qubits.
Salt-In-Polymer Electrolytes Based on Polysiloxanes for Lithium-Ion Cells: Ionic Transport and Electrochemical Stability
Authors: Hiller Martin M. , Gentschev Ann-Christin , Amereller Marius , Gores Heiner , Winter Martin , Wiemhöfer Hans D.
Published: March 2011

In this work, the ion transport and the electrochemical stability has been investigated for cross linked salt-in-polysiloxane membranes containing the two lithium salts with boron based anions, i.e. LiDFOB (lithium difluoro(oxalato)borate) and LiBOB (lithium bis(oxalato)borate) have been investigated. The stability was characterized by cyclic voltammetry at 70 °C in a three electrode cell with Li as counter and reference electrodes and a nickel or platinum working electrode. The electrochemical stability window of polysiloxane based electrolytes ranged between 0 V and 4.7 V vs. Li/Li+. The high ionic conductivity of 6.61 x 10-2 mS/cm at 30 C has been examined with impedance spectroscopy on blocking electrodes. The investigated polymer electrolytes showed an outstanding thermal resistance as confirmed by thermal analysis with DSC. Furthermore, analysis of the lithium transference number has been carried out using the potentiostatic polarization method introduced by BRUCE and VINCENT.
Structural Investigation of Polyvinyl Alcohol Gel Electrolyte by Small Angle X-ray Scattering
Authors: Chatterjee Jhunu , Liu Tao , Wang Ben , Zheng Jim P.
Published: March 2011

Polyvinyl alcohol based organogel electrolytes are a promising class of materials for lithium batteries and electrochemical supercapacitors. Amongst various classes of polymer electrolytes polymer based gel electrolytes have proven to be a materials for safer battery assembly with fast ion carrying capacity and better mechanical strength. Internal structure of gel is responsible for its ion conduction mechanism. This paper presents small angle X-ray scattering(SAXS) results for polyvinyl alcohol during its gelation in an organic solvent and salt system. Structural changes are observed during and after gelation for samples with varying polymer and lithium salt concentration and has been well documented by the SAXS results.
Li-Ion Battery Performance with FSI-Based Ionic Liquid Electrolyte and Fluorinated Solvent-Based Electrolyte
Authors: Ishikawa Masashi , Yamagata Masaki , Sugimoto Toshinori , Atsumi Yosuke , Kitagawa Takeshi , Azuma Kazuki
Published: March 2011

We evaluated the electrochemical behavior of a LiNi1/3Mn1/3Co1/3O2 (NMC) electrode in a neat ionic liquid, 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMImFSI), electrolyte. According to charge/discharge measurements, the discharge capacity of the NMC cathode in EMImFSI at 1 C in a voltage range of 3.0-4.5 (vs. Li/Li+) shows 165 mAh g-1, which is higher than that in a conventional electrolyte, EC+DMC. The rate capability of a cell with EMImFSI exceeds that with EC+DMC, especially at high rates, probably due to a low resistance at the electrode/electrolyte interface. These results suggest that EMImFSI is a suitable electrolyte for Li-ion batteries utilizing a NMC cathode. Also, we applied fluorine-containing solvents (FCSs) to an electrolyte for Li-ion batteries with a cobalt oxide (LiCoO2) cathode to enhance the upper voltage limit and investigated its electrochemical properties in a proposed FCS-based electrolyte. A test cell containing a FCS-based electrolyte exhibits high and stable discharge capacity for 30 cycles even with a high upper cutoff voltage of 4.5 V when compared with a cell containing a conventional electrolyte.
Charge and Discharge Property of Li/LiCoO2 Cell Using Ionic Liquids Composed of N,N-Diethyl-N-Methyl-N-(2-Methoxyethyl)Ammonium and Fluorosulfonyl (Trifluoromethylsulfonyl) Amide
Authors: Matsumoto Hajime , Terasawa Naohiro , Tsuzuki Seiji , Sakaebe Hikari
Published: March 2011

The rate property of Li/LiCoO2 cell using ionic liquids (ILs) containing fluorosulfonyl(trifluoromethylsulfonyl) amide (FTA−) anion and N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium (DEME+) was investigated. comparing with corresponding amide ionic liquids composed of such bis(trifluoromethyl)sulfonylamide (TFSA−) and bis(fluoromethylsulfonyl)amide (FSA−). As a result, the cell using DEME[FTA] was also exhibit good rate performance as in the case of DEME[FSA]. This result suggests that an existence of FSO2 group in anionic species might be a key factor to improve the battery performance containing neat ILs.
New Insight into Differences in Cycling Behaviors of a Lithium-ion Battery Cell Between the Ethylene Carbonate- and Propylene Carbonate-Based Electrolytes
Authors: Tasaki Ken , Goldberg Alexander , Liang Jian-Jie , Winter Martin
Published: March 2011

Density functional theory (DFT) calculations and classical molecular dynamics (MD) simulations have been performed to gain insight into the difference in cycling behaviors between the ethylene carbonate (EC)-based and the propylene carbonate (PC)-based electrolytes in lithium-ion battery cells. DFT calculations for the ternary graphite intercalation compounds (Li+(S)iCn: S=EC or PC), in which the solvated lithium ion Li+(S)i (i=1~3) was inserted into a graphite cell, suggested that Li+(EC)iCn was more stable than Li+(PC)iCn in general. In addition, MD simulations were carried out to examine the solvation structures at a high salt concentration: 2.45 mol kg-1. The results showed that the solvation structure was significantly interrupted by the counter anions, having a smaller solvation number than that at a lower salt concentration (0.83 mol kg-1). The results from both DFT calculations and MD simulations are consistent with the recent experimental observations.
Investigation of Lithium Tetrafluorooxalatophosphate [LiPF4(C2O4)] Based Electrolytes
Authors: Zhou Liu , Dalavi Swapnil , Xu Mengqing , Lucht Brett
Published: March 2011

The novel electrolyte, lithium tetrafluorooxalatophosphate (LiPF4(C2O4)), was investigated with various electrodes (graphite, LiNi1/3Co1/3Mn1/3O2, LiFePO4 and LiMn2O4). The room temperature cycling performance of LiPF4(C2O4) is compared to LiPF6 electrolytes.
Study of the LiMn1.5Ni0.5O4/Electrolyte Interface at Room Temperature and 60°C
Authors: Duncan Hugues , Duguay Dominique , Abu-Lebdeh Yaser , Davidson Isobel J.
Published: March 2011

The surface layer (Cathode-Electrolyte Interface; CEI) on LiMn1.5Ni0.5O4, a promising, high voltage positive electrode for Li-ion batteries, was studied by XPS, AC impedance spectroscopy and FTIR spectroscopy. Half cells and full cells with LiMn1.5Ni0.5O4as positive electrode material and Li4Ti5O12as a negative electrode material were assembled in conventional carbonate-based electrolytes with LiPF6or LiBF4as the salt, and the effect of cycling at different operating conditions (short and long storage time, state of charge and temperature) on the surface layer composition was assessed. Capacities reaching near the theoretical value of 140 mAh g−1were obtained in half cells cycled at C/2 and room temperature, with 85% of the capacity being retained after 100 cycles. Cycling at 60°C leads to a decrease in capacity and coulombic efficiency. The surface analysis by XPS revealed that the CEI is composed of inorganic species such as LiF and LixPFyOzor LixBFyOzas well as organic species such as polyethers and carbonates. Generally, it was found that cycling or storing the material at 60°C with an electrolyte using LiPF6as a salt yield more organic species and less LiF at the surface than the one with LiBF4.
AMP-activated protein kinase rescues the angiogenic functions of endothelial progenitor cells via manganese superoxide dismutase induction in type 1 diabetes
Authors: Wang Xiao-Rong , Zhang Ming-Wei , Chen Dan-Dan , Zhang Yun , Chen Alex F.
Published: March 2011

Endothelial progenitor cells (EPCs) play an essential role in angiogenesis but are functionally impaired in diabetes. We recently reported that decreased expression of manganese superoxide dismutase (MnSOD) critically contributes to diabetic EPC dysfunction. AMP-activated protein kinase (AMPK) activation has been shown to induce MnSOD and suppress hyperglycemia-induced mitochondrial ROS production in endothelial cells. However, whether AMPK protects EPCs from oxidative stress in diabetes is unknown. We tested the hypothesis that AMPK activation rescues impaired EPC functions through MnSOD induction in type 1 diabetes. Bone marrow-derived EPCs from adult male streptozotocin-induced diabetic mice and normal controls were used. AMPK activity was decreased in diabetic EPCs, indicated by reduced AMPK and acetyl-CoA carboxylase phosphorylation. AMPK activation by treating diabetic EPCs with its selective agonist AICAR rescued their in vitro functions, including Matrigel tube formation, adhesion, and migration. Furthermore, AICAR restored the decreased MnSOD protein and enzymatic activity and suppressed the mitochondrial superoxide level in diabetic EPCs, indicated by MitoSOX flow cytometry. These beneficial effects of AICAR on MnSOD and EPC functions were significantly attenuated by silencing MnSOD or AMPK antagonist compound C pretreatment. Finally, the expression of protein phosphatase 2A, a key enzyme for AMPK dephosphorylation and inactivation, was increased in diabetic EPCs, and its inhibition by siRNA or okadaic acid reversed the deficient AMPK activation and MnSOD level in diabetic EPCs. These findings demonstrate for the first time that AMPK activation rescues impaired EPC functions and suppresses mitochondrial superoxide by inducing MnSOD in type 1 diabetes.
Scheduled feeding results in adipogenesis and increased acylated ghrelin
Authors: Verbaeys I. , Tolle V. , Swennen Q. , Zizzari P. , Buyse J. , Epelbaum J. , Cokelaere M.
Published: March 2011

Ghrelin, known to stimulate adipogenesis, displays an endogenous secretory rhythmicity closely related to meal patterns. Therefore, a chronic imposed feeding schedule might induce modified ghrelin levels and consequently adiposity. Growing Wistar rats were schedule-fed by imposing a particular fixed feeding schedule of 3 meals/day without caloric restriction compared with total daily control intake. After 14 days, their body composition was measured by DEXA and compared with ad libitum-fed controls and to rats daily intraperitoneal injection with ghrelin. Feeding patterns, circadian activity, and pulsatile acylated ghrelin variations were monitored. After 14 days, rats on the imposed feeding schedule displayed, despite an equal daily calorie intake, a slower growth rate compared with ad libitum-fed controls. Moreover, schedule-fed rats exhibiting a feeding pattern with intermittent fasting periods had a higher fat/lean ratio compared with ad libitum-fed controls. Interestingly, ghrelin-treated rats also showed an increase in fat mass, but the fat/lean ratio was not significantly increased compared with controls. In the schedule-fed rats, spontaneous activity and acylated ghrelin levels were increased and associated with the scheduled meals, indicating anticipatory effects. Our results suggest that scheduled feeding, associated with intermittent fasting periods, even without nutrient/calorie restriction on a daily basis, results in adipogenesis. This repartitioning effect is associated with increased endogenous acylated ghrelin levels. This schedule-fed model points out the delicate role of meal frequency in adipogenesis and provides an investigative tool to clarify any effects of endogenous ghrelin without the need for ghrelin administration.
Architecture of energy balance traits in emerging lines of the Collaborative Cross
Authors: Mathes Wendy Foulds , Aylor David L. , Miller Darla R. , Churchill Gary A. , Chesler Elissa J. , de Villena Fernando Pardo-Manuel , Threadgill David W. , Pomp Daniel
Published: March 2011

The potential utility of the Collaborative Cross (CC) mouse resource was evaluated to better understand complex traits related to energy balance. A primary focus was to examine if genetic diversity in emerging CC lines (pre-CC) would translate into equivalent phenotypic diversity. Second, we mapped quantitative trait loci (QTL) for 15 metabolism- and exercise-related phenotypes in this population. We evaluated metabolic and voluntary exercise traits in 176 pre-CC lines, revealing phenotypic variation often exceeding that seen across the eight founder strains from which the pre-CC was derived. Many phenotypic correlations existing within the founder strains were no longer significant in the pre-CC population, potentially representing reduced linkage disequilibrium (LD) of regions harboring multiple genes with effects on energy balance or disruption of genetic structure of extant inbred strains with substantial shared ancestry. QTL mapping revealed five significant and eight suggestive QTL for body weight (Chr 4, 7.54 Mb; CI 3.32–10.34 Mb; Bwq14), body composition, wheel running (Chr 16, 33.2 Mb; CI 32.5–38.3 Mb), body weight change in response to exercise (1: Chr 6, 77.7Mb; CI 72.2–83.4 Mb and 2: Chr 6, 42.8 Mb; CI 39.4–48.1 Mb), and food intake during exercise (Chr 12, 85.1 Mb; CI 82.9–89.0 Mb). Some QTL overlapped with previously mapped QTL for similar traits, whereas other QTL appear to represent novel loci. These results suggest that the CC will be a powerful, high-precision tool for examining the genetic architecture of complex traits such as those involved in regulation of energy balance.
Alterations in the proteome of the NHERF2 knockout mouse jejunal brush border membrane vesicles
Authors: Donowitz M. , Singh S. , Singh P. , Chakraborty M. , Chen Y. , Murtazina R. , Gucek M. , Cole R. N. , Zachos N. C. , Salahuddin F. F. , Kovbasnjuk O. , Broere N. , Smalley-Freed W. G. , Reynolds A. B. , Hubbard A. L. , Seidler U. , Weinman E. , de Jonge H. R. , Hogema B. M. , Li X.
Published: March 2011

To identify additional potential functions for the multi-PDZ domain containing protein Na+/H+exchanger regulatory factor 2 (NHERF2), which is present in the apical domain of intestinal epithelial cells, proteomic studies of mouse jejunal villus epithelial cell brush border membrane vesicles compared wild-type to homozygous NHERF2 knockout FVB mice by a two-dimensional liquid chromatography-tandem mass spectrometry (LC-MS/MS)-iTRAQ approach. Jejunal architecture appeared normal in NHERF2 null in terms of villus length and crypt depth, Paneth cell number, and microvillus structure by electron microscopy. There was also no change in proliferative activity based on BrdU labeling. Four brush border membrane vesicles (BBMV) preparations from wild-type mouse jejunum were compared with four preparations from NHERF2 knockout mice. LC-MS/MS identified 450 proteins in both matched wild-type and NHERF2 null BBMV; 13 proteins were changed in two or more separate BBMV preparations (9 increased and 4 decreased in NHERF2 null mice), while an additional 92 proteins were changed in a single BBMV preparation (68 increased and 24 decreased in NHERF2 null mice). These proteins were categorized as 1) transport proteins (one increased and two decreased in NHERF2 null); 2) signaling molecules (2 increased in NHERF2 null); 3) cytoskeleton/junctional proteins (4 upregulated and 1 downregulated in NHERF2 null); and 4) metabolic proteins/intrinsic BB proteins) (2 upregulated and 1 downregulated in NHERF2 null). Immunoblotting of BBMV was used to validate or extend the findings, demonstrating increase in BBMV of NHERF2 null of MCT1, coronin 3, and ezrin. The proteome of the NHERF2 null mouse small intestinal BB demonstrates up- and downregulation of multiple transport proteins, signaling molecules, cytoskeletal proteins, tight junctional and adherens junction proteins, and proteins involved in metabolism, suggesting involvement of NHERF2 in multiple apical regulatory processes and interactions with luminal contents.
Positivity and Stability of the Solutions of Caputo Fractional Linear Time‐Invariant Systems of Any Order with Internal Point Delays
Authors: De la Sen M.
Published: March 2011

This paper is devoted to the investigation of the nonnegative solutions and the stability and asymptotic properties of the solutions of fractional differential dynamic systems involving delayed dynamics with point delays. The obtained results are independent of the sizes of the delays.
Some Topological and Geometrical Properties of a New Difference Sequence Space
Authors: Demiriz Serkan , Çakan Celal
Published: March 2011

We introduce the new difference sequence space . Further, it is
proved that the space is the BK‐space including the space bvp, which is the space of sequences of pbounded
variation. We also show that the spaces , and ℓp are linearly isomorphic for 1 ≤ p < ∞.
Furthermore, the basis and the α‐, β‐ and
γ‐duals of the space are determined. We devote
the final section of the paper to examine some geometric properties of the space .
Initial Feasibility of a Woman-Focused Intervention for Pregnant African-American Women
Authors: Jones Hendrée E. , Berkman Nancy D. , Kline Tracy L. , Ellerson Rachel Middlesteadt , Browne Felicia A. , Poulton Winona , Wechsberg Wendee M.
Published: March 2011

African-American women who use crack are vulnerable to HIV because of the complex social circumstances in which they live. Drug-abuse treatment for these women during pregnancy may provide time for changing risk behaviors. This paper examines the initial 6-month feasibility of a women-focused HIV intervention, the Women's CoOp, adapted for pregnant women, relative to treatment-as-usual among 59 pregnant African-American women enrolled in drug-abuse treatment. At treatment entry, the women were largely homeless, unemployed, practicing unsafe sex, and involved in violence. Results indicated marked reductions in homelessness, use of cocaine and illegal drugs, involvement in physical violence, and an increase in knowledge of HIV from baseline to 6-month followup for both conditions. Findings suggest that the Women's CoOp intervention could be successfully adapted to treat this hard-to-reach population. Future studies should examine the efficacy of the pregnancy-adapted Women's CoOp for women not enrolled in drug-abuse treatment.
Discovering the Unknown: Improving Detection of Novel Species and Genera from Short Reads
Authors: Rosen Gail L. , Polikar Robi , Caseiro Diamantino A. , Essinger Steven D. , Sokhansanj Bahrad A.
Published: March 2011

High‐throughput sequencing technologies enable metagenome
profiling, simultaneous sequencing of multiple microbial species
present within an environmental sample. Since metagenomic data
includes sequence fragments (“reads”) from organisms
that are absent from any database, new algorithms must be
developed for the identification and annotation of novel sequence
fragments. Homology‐based techniques have been modified to detect
novel species and genera, but, composition‐based methods, have not
been adapted. We develop a detection technique that can
discriminate between “known” and “unknown”
taxa, which can be used with composition‐based methods, as well as
a hybrid method. Unlike previous studies, we rigorously evaluate
all algorithms for their ability to detect novel taxa. First, we
show that the integration of a detector with a composition‐based
method performs significantly better than homology‐based methods
for the detection of novel species and genera, with best
performance at finer taxonomic resolutions. Most importantly, we
evaluate all the algorithms by introducing an
“unknown” class and show that the modified version of
PhymmBL has similar or better overall classification performance
than the other modified algorithms, especially for the
species‐level and ultrashort reads. Finally, we evaluate the
performance of several algorithms on a real acid mine drainage
dataset.
Robust Optimization‐Based Generation Self‐Scheduling under Uncertain Price
Authors: Luo Xiao , Chung Chi-yung , Yang Hongming , Tong Xiaojiao
Published: March 2011

This paper considers generation self‐scheduling in electricity markets under uncertain price. Based on the robust optimization (denoted as RO) methodology, a new self‐scheduling model, which has
a complicated max‐min optimization structure, is set up. By using optimal dual theory, the proposed model is reformulated to an ordinary quadratic and quadratic cone programming problems in the cases of box and ellipsoidal uncertainty, respectively. IEEE 30‐bus system is used to test the new model. Some comparisons with other methods are done, and the sensitivity with respect to the uncertain set is analyzed. Comparing with the existed uncertain self‐scheduling approaches, the new method has twofold characteristics. First, it does not need a prediction of distribution of random variables and just requires an estimated value and the uncertain set of power price. Second, the counterpart of RO corresponding to the self‐scheduling is a simple quadratic or quadratic cone programming. This indicates that the reformulated problem can be solved by many ordinary optimization algorithms.
On a Result of Levin and Stečkin
Authors: Gao Peng
Published: March 2011

The following inequality for 0 < p < 1 and an ≥ 0 originates from a study of Hardy, Littlewood, and Pólya: . Levin and Stečkin proved the previous inequality with the best constant cp = (p/(1 − p)) p for 0 < p ≤ 1/3. In this paper, we extend the result of Levin and Stečkin to 0 < p ≤ 0.346.
Tumor-Associated Neutrophils: New Targets for Cancer Therapy
Authors: Gregory Alyssa D. , McGarry Houghton A.
Published: March 2011

Studies have begun to emerge showing critical roles for neutrophils in tumorigenesis. Neutrophils can have a significant impact on the tumor microenvironment via their production of cytokines and chemokines, which influence inflammatory cell recruitment and activation. Additionally, products secreted from neutrophils, such as reactive oxygen species and proteinases, have defined and specific roles in regulating tumor cell proliferation, angiogenesis, and metastasis. Although evidence suggests that neutrophils act in a decidedly protumor capacity in vivo, recent studies indicate that neutrophils may be manipulated to exhibit cytotoxicity against tumors. Herein, we explore the idea of targeting tumor-associated neutrophils as a means of antitumor therapy and the important ramifications such manipulation could pose to host tissues. Cancer Res; 71(7); 2411–6. ©2011 AACR.
MicroRNA-95 Promotes Cell Proliferation and Targets Sorting Nexin 1 in Human Colorectal Carcinoma
Authors: Huang Zhaohui , Huang Shenglin , Wang Qifeng , Liang Linhui , Ni Shujuan , Wang Lisha , Sheng Weiqi , He Xianghuo , Du Xiang
Published: March 2011

MicroRNAs (miRNAs) are strongly implicated in cancer but their specific roles and functions in the major cancers have yet to be fully elucidated. In this study, we defined the oncogenic significance and function of miR-95, which we found to be elevated in colorectal cancer (CRC) tissues by microarray analysis. Evaluation of an expanded CRC cohort revealed that miR-95 expression was up-regulated in nearly half of the tumors examined (42/87) compared with the corresponding noncancerous tissues. Ectopic overexpression of miR-95 in human CRC cell lines promoted cell growth in vitro and tumorigenicity in vivo, whereas RNAi-mediated silencing of miR-95 decreased cell growth ratio. Mechanistic studies revealed that miR-95 repressed the expression of reporter gene coupled to the 3′-untranslated region of sorting nexin 1 (SNX1), whereas miR-95 silencing up-regulated SNX1 expression. Moreover, miR-95 expression levels correlated inversely with SNX1 protein levels in human CRC tissues. RNAi-mediated knockdown of SNX1 phenocopied the proliferation-promoting effect of miR-95, whereas overexpression of SNX1 blocked miR-95–induced proliferation of CRC cells. Taken together, these results demonstrated that miR-95 increases proliferation by directly targeting SNX1, defining miR-95 as a new oncogenic miRNA in CRC. Cancer Res; 71(7); 2582–9. ©2011 AACR.
S6 Kinase 2 Promotes Breast Cancer Cell Survival via Akt
Authors: Sridharan Savitha , Basu Alakananda
Published: March 2011

The 40S ribosomal protein S6 kinase (S6K) acts downstream of mTOR, which plays important roles in cell proliferation, protein translation, and cell survival and is a target for cancer therapy. mTOR inhibitors are, however, of limited success. Although Akt is believed to act upstream of mTOR, persistent inhibition of p70 S6 kinase or S6K1 can activate Akt via a negative feedback loop. S6K exists as two homologues, S6K1 and S6K2, but little is known about the function of S6K2. In the present study, we have examined the effects of S6K2 on Akt activation and cell survival. Silencing of S6K1 caused a modest decrease, whereas knockdown of S6K2 caused a substantial increase in TNF-α and TRAIL (TNF-related apoptosis-inducing ligand)-mediated apoptosis. In contrast to S6K1, depletion of S6K2 by siRNA decreased basal and TNF-induced Akt phosphorylation. Ectopic expression of constitutively active Akt in MCF-7 cells restored cell survival in S6K2-depleted cells. We have previously shown that activation of Akt induces downregulation of Bid via p53. Knockdown of S6K2 caused an increase in p53, and downregulation of p53 by siRNA decreased Bid level. Silencing of Bid blunted the ability of S6K2 deficiency to enhance TNF-induced apoptosis. Taken together, our study shows that the two homologues of S6K have distinct effects on Akt activation and cell survival. Thus, targeting S6K2 may be an effective therapeutic strategy to treat cancers. Cancer Res; 71(7); 2590–9. ©2011 AACR.
Insulin Receptor Activation in Deletion 11q Chronic Lymphocytic Leukemia
Authors: Brown Jennifer R.
Published: March 2011

The chromosomal abnormalities characteristic of chronic lymphocytic leukemia (CLL) are well studied, but the mechanisms underlying their contribution to pathogenesis are only partially elucidated. Integrated genomic profiling, focused on deletion 11q, has identified elevated expression of the insulin receptor in a subgroup of CLLs and associated it with worse outcomes. Clin Cancer Res; 17(9); 2605–7. ©2011 AACR.
Participation in Cancer Clinical Trials as Viewed by Chinese Patients and Their Families
Authors: Li Jun-ying , Yu Chun-hua , Jiang Yu
Published: March 2011

Objective: To evaluate the attitude of Chinese cancer patients and their families toward clinical trials. Methods: A questionnaire was administered to 578 pairs of cancer patients and their relatives. Results: Of the 712 pairs of participants contacted, 578 pairs completed the questionnaire (effective response rate 81.2%). Over half of the participants have heard about cancer clinical trials. Among the respondents, 54.5% of the patients would consider participation in an early-stage cancer clinical trial, 68.7% with advanced cancer without previous therapy and 75.6% with advanced cancer not responding to prior therapy would consider participation in a clinical trial. Willingness to participate in a clinical trial was affected by disease stage. No significant differences were observed between the attitudes of patients and families. Participants who had never heard of clinical trials were more willing to participate in a cancer clinical trial. The major reasons for willingness to participate in a cancer clinical trial were ‘doctor suggests’ or ‘more therapy chance’. The major reasons for patients not to participate were ‘the effect of new drug is unknown’ and ‘not want to be a guinea pig’. Conclusions: Most patients were willing to join a cancer clinical trial and no significant difference was observed between the attitudes of patients and their families.
Identification of the Sex Chromosomes of Brown Trout (Salmo trutta) and Their Comparison with the Corresponding Chromosomes in Atlantic Salmon (Salmo salar) and Rainbow Trout (Oncorhynchus mykiss)
Authors: Li J. , Phillips R.B. , Harwood A.S. , Koop B.F. , Davidson W.S.
Published: March 2011

Males are the heterogametic sex in salmonid fishes. In brown trout (Salmo trutta) the sex-determining locus, SEX, has been mapped to the end of linkage group BT-28, which corresponds to linkage group AS-8 and chromosome SSA15 in Atlantic salmon (Salmo salar). We set out to identify the sex chromosomes in brown trout. We isolated Atlantic salmon BAC clones containing microsatellite markers that are on BT-28 and also on AS-8, and used these BACs as probes for fluorescent in situ hybridization (FISH) analysis. SEX is located on the short arm of a small subtelocentric/acrocentric chromosome in brown trout, which is consistent with linkage analysis. The acrocentric chromosome SSA15 in Atlantic salmon appears to have arisen by a centric fusion of 2 small acrocentric chromosomes in the common ancestor of Salmo sp. We speculate that the fusion process that produced Atlantic salmon chromosome SSA15 disrupted the ancestral sex-determining locus in the Atlantic salmon lineage, providing the impetus either for the relocation of SEX or selection pressure for a novel sex-determining gene to arise in this species. Thus, the sex-determining genes may differ in Atlantic salmon and brown trout.