bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Study of Wake Shielding Effects of Three Cylinders in Currents
Authors: Huang Shan , Bolstad Jarle , Maro´n Adolfo
Published: January 2009

A large amount of experimental work has been carried out in the past to understand forces on a single cylinder in cross flows. In comparison substantially less work can be found on the interference between multiple cylinders and the number of publications available becomes drastically smaller as the number of cylinders involved increases. The current experimental work systematically examines the wake shielding effects of three cylinders by testing in a towing tank. Though staggered, the three cylinders are arranged mainly along the flow direction. The tests are carried out in the subcritical and critical Reynolds number regimes. Significant drag reduction on downstream cylinders is identified.
Nonlinear Internal Waves: A Numerical Investigation of 2D Sloshing
Authors: Valentine Daniel T.
Published: January 2009

This paper examines internal sloshing motions in 2-D numerical wave tanks subjected to horizontal excitation. In all of the cases studied, the rectangular tank of liquid has a width-to-depth ratio of 2. The results presented are from simulations of internal waves induced by sloshing a density-stratified liquid. Non-linear, viscous flow equations of a Newtonian, Boussinesq liquid are solved. Some of the features of the evolution of sloshing in nearly two-layer and three-layer fluid systems are described. Initially, the middle of the two layers and the center of the middle layer of the three layers are horizontal and located at the center of the tank. The two-layer cases are forced at resonance. The evolution of sloshing from rest is examined. The maximum amplitude of sloshing occurs during the initial transient. If breaking occurs it is at the center of the container in the two-layer cases. The subharmonic forcing of a three-layer case induces a resonant response with the middle layer moving in such a way that motion is perpendicular to the isopycnals within this layer. These model problems provide some insights into the relatively complex sloshing that can occur in density-stratified liquids.
Wave Loading on a Moored OWC Wave Energy Device
Authors: Finnigan Timothy
Published: January 2009

This paper describes results from wave tank testing on a 1/25 scale model of a moored oscillating water column (OWC) wave energy device. The device incorporates a piece-wise linear parabolic wall to focus the waves onto a three-sided OWC chamber. Model tests were conducted to determine the mooring line loads and associated structure motions in both a taut-moored floating configuration and a semi-fixed configuration. All six degrees of motion were recorded continuously along with forces in twelve mooring lines. Tests were conducted for a range of wave conditions and angles of incidence. For a device with a 35m wide parabolic wall (prototype scale), peak mooring line forces below 350Te were measured. In extreme conditions, heave motions were found to exceed design requirements in the floating configuration but this was rectified in the semi-fixed configuration. The paper presents a summary of the average results found and some of the dynamic response characteristics of the structure in various sea conditions. Implications for full-scale design and operation of the device are also discussed.
Numerical Simulation of the 3D Viscous Flow Around a Vertical Cylinder in Non-Linear Waves Using an Explicit Incident Wave Model
Authors: Gentaz L. , Luquet R. , Alessandrini B. , Ferrant P.
Published: January 2009

The numerical simulation of 3D wave-body interaction problems in viscous fluid still leads to numerical difficulties, mainly due to large grid and CPU time requirements, especially for wave generation and propagation aspects. The correct treatment of open boundary conditions also remains problematic in direct approaches The method proposed here allows to avoid these problems by solving a modified problem for the diffracted flow only, the incident wave field being explicitly described by potential flow models. A set of results, both on 2D and 3D geometries is presented and commented, showing the capacity of the proposed scheme to solve problems of practical interest in ocean or offshore engineering in an efficient and accurate manner.
Risk Assessment for Geotechnical Solutions Offshore (Invited Lecture)
Authors: Lacasse Suzanne
Published: January 2009

More and more frequently, it is required to quantify risk in practice. Statistics, reliability analysis and risk assessment are important tools to account for uncertainties and to assist the process of decision-making. After briefly reviewing concepts of uncertainties, reliability, safety and risk, the paper presents applications and approaches for offshore geotechnical practice. Methods for analysis of bearing capacity and settlement to couple statistical observations, e.g. from geological evidence of underwater slope instability, and computed failure probabilities are presented. The geotechnical profession needs to improve its understanding of geological risks and its ability to deal with them. Risk perception in society triggers discussion of acceptable risk level and public protection guidelines. The paper concludes that the profession can only gain by implementing in practice more systematically than before probabilistic and risk-based thinking and, where appropriate, risk-based methodology.
An Assessment of Structural Details in Lightweight Marine Structures
Authors: Pereira Carlos A. , Silva Paulo P. , Mateus Anto´nio F. , Witz Joel A.
Published: January 2009

This paper presents the results of investigations into the mechanics and failure modes of structural details usually encountered in lightweight marine structures. The structural analyses are performed using non-linear finite element analysis. The stress concentration factors and expected fatigue lives of the as designed and the as built structural details are evaluated and alternative configurations are discussed with the aim of improving the designs for production.
Studies on Model Caissons Embedded in Marine Clay for Coastal Protection Wall
Authors: Kumar N. Darga , Rao S. Narasimha , Sundar V.
Published: January 2009

Caissons can be used as embedded walls in marine environment for protecting the coast from severe erosion caused by waves and currents. The design of these embedded caissons requires proper evaluation of lateral passive earth pressures, base pressures and deflections. In this paper, an attempt has been made to arrive at ground level deflections, base pressures and tilts of model caissons under lateral static and cyclic loading and some interesting conclusions are brought out. The mobilization rate of ground level deflection is slow in the initial period up to a deflection of 10% of diameter of caisson. The ultimate base pressure is partly controlled by liquidity index. For a given load cycles, tilt in a caisson is observed to be more at higher values of CLR (CLR is defined as the ratio of applied cyclic load to the ultimate static lateral load). Also, based on the observations, an equation was suggested between ground level deflection and tilt.
Design Robustness Saves Marco Polo Oil SCR During Its Installation
Authors: Mekha Basim B. , O’Sullivan Enda , Nogueira Andre
Published: January 2009

The Marco Polo TLP, located in Green Canyon Block 608 in 4300 ft water depth exports oil and gas through 12-inch oil and 18-inch gas export SCRs that are connected to Marco Polo 14-inch oil and 18inch/20-inch gas export pipelines. Following completion of the installation of the 14-inch oil export pipeline and during the installation of the 12-inch oil export SCR on the seabed (with about 3,000 ft or 77 SCR pipe joints still to go), the operation had to be abandoned due to bad weather and the SCR pipe lowered to the seabed. During the abandonment operation, a high tension event occurred, causing the transition joint between the 14-inch and 12-inch pipes to slide by about 820 ft toward the TLP. This would have the effect of changing the touchdown position along the SCR and consequently the Three Layer Polyethylene abrasion coating would not be located at the at the touchdown to perform its function. In order to move the SCR touchdown area at least partially to the TLPE region, it was decided that four extra joints would be welded to the SCR resulting in the SCR departure angle to changing from 12 degrees to 10 degrees. This paper presents the methodology used for the original design of the oil export SCR and the design robustness, flexibility and margins that allowed for the design to be modified in the last minutes without compromising the integrity of the SCR. The paper also discuss the steps taken to ensure that the modified design is acceptable and within the code requirements. Some strength and fatigue results are presented.
On the Dynamics of the Three-Piece-Freight Truck
Authors: Xia Fujie , True Hans
Published: January 2009

This paper is based on part of Fujie Xia’s PhD-thesis [8] on the modelling and dynamics of the Three-Piece-Freight Truck.
Identifying and Reducing Scaling Problems in Solar Hot Water Systems
Authors: Baker Derek K. , Vliet Gary C.
Published: January 2009

In areas with hard water, scaling can reduce the reliability of solar hot water (SHW) systems. Common reliability problems associated with scaling are both mechanical (collector freeze damage, clogged passages, premature failure of pumps and valves) and thermal (efficiency degradation). A mechanistic and a mathematical scaling rate model are presented. Results from controlled experiments investigating the effect of key water chemistry and heat transfer parameters on the scaling rate are summarized. The implications of these results for designing SHW systems for scaling environments are discussed. Most importantly, indirect systems where the potable water side of the heat exchanger is integrated into the storage tank wall, such as in a wrap-around heat exchanger, are shown to be the most mechanically and thermally reliable systems for scaling environments. A new version of the software SolScale is discussed, which is intended to aid in the design of SHW systems to reduce scaling related reliability problems.
Design and Performance of the Amonix High Concentration Solar PV System
Authors: Stone Kenneth W. , Garboushian Vahan , Hayden Herb
Published: January 2009

Amonix has designed, manufactured, installed, and tested over 500 kW of high concentrating PV systems based around a concentrating silicon cell that set a new world efficiency record in 1992. This paper describes the development of this product as well as the physical and operating characteristics of the system. The operating characteristics that make this system attractive for grid, distributed, and off-grid are discussed. Data is presented that demonstrates the high daily power generating capability and the energy performance of the concentrating PV system. Other attributes of the system are also discussed such as the automatic/unattended operation, the short installation time, etc. An array installed at Pomona, CA is described, it has operated unattended for over 3 years and is still producing power today.
Net Energy Analysis for Sustainable Energy Production From Silicon Based Solar Cells
Authors: Pearce Joshua , Lau Andrew
Published: January 2009

A number of detailed studies on the energy requirements on the three types of photovoltaic (PV) materials, which make up the majority of the active solar market: single crystal, polycrystalline, and amorphous silicon were reviewed. It was found that modern PV cells based on these silicon technologies pay for themselves in terms of energy in a few years (1–5 years). They thus generate enough energy over their lifetimes to reproduce themselves many times (6–31 reproductions) depending on what type of material, balance of system, and the geographic location of the system. It was found that regardless of material, built-in PV systems are a superior ecological choice to centralized PV plants. Finally, the results indicate that efficiency plays a secondary role to embodied energy in the overall net energy production of modern solar cells.
Numerical Analysis of Surface Deformation and Adhesion by Lennard-Jones Interaction Potential
Authors: Biwa S. , Iwata S. , Kakoi K. , Ohno N.
Published: January 2009

A numerical procedure for the surface deformation and adhesion between elastic half-spaces interacting by the Lennard-Jones surface potential is presented. The problem is solved based on the superposition of Boussinesq solutions for a half-space, with an iteration procedure to incorporate the nonlinear surface force-depression relation. First the axisymmetric contact between a sphere and a plane surface is demonstrated to show the validity of the procedure for a wide range of the Tabor parameter. The method is then applied to the contact between a sphere and a wavy surface, and the influence of the surface waviness on the adhesive behavior is illustrated.
ON ACHIEVING THE SHORTEST-PATH ROUTING IN 2-D MESHES
Authors: JIANG ZHEN , WU JIE
Published: January 2009

In this paper, we present a fully distributed process to collect and distribute the minimal connected component (MCC) fault information so that the shortest-path between a source and its destination can always be found in the corresponding information-based routing via routing decisions made at each intermediate node. Considering the communication cost in the above information distribution, a more practical implementation is provided with a low number of nodes involved in the information propagation. The experimental results show substantial improvement of our approach in terms of the success rate in finding the shortest-path and the average path length.
SIMULATING AN R-MESH ON AN LR-MESH IN CONSTANT TIME
Authors: FERNÁNDEZ-ZEPEDA JOSÉ ALBERTO , CÓRDOVA-FLORES CARLOS ALBERTO , BOURGEOIS ANU G.
Published: January 2009

Recently, many parallel computing models using dynamically reconfigurable electrical buses have been proposed in the literature. The underlying characteristics are similar among these models, but they do have certain differences that can take the form of restrictions on configurations allowed. This paper presents a constant time simulation of an R-Mesh on an LR-Mesh (a restricted model of the R-Mesh), proving that in spite of the differences, the two models possess the same complexity. In other words, the LR-Mesh can simulate a step of the R-Mesh in constant time with a polynomial increase in size. This simulation is based on Reingold's algorithm to solve USTCON in log-space. The simulation is also the first to be executed in constant time. The only drawback of this simulation is that the resources required by the LR-Mesh to simulate the R-Mesh are quite big, which is not suitable for any practical application.
A NEW FM SCREENING METHOD TO GENERATE CLUSTER-DOT BINARY IMAGES USING THE LOCAL EXHAUSTIVE SEARCH WITH FPGA ACCELERATION
Authors: ITO YASUAKI , NAKANO KOJI
Published: January 2009

Screening is an important task to convert a continuous-tone image into a binary image with pure black and white pixels. The main contribution of this paper is to show a new algorithm for cluster-dot screening using a local exhaustive search. Our new algorithm generates 2-cluster, 3-cluster, and 4-cluster binary images, in which all dots have at least 2, 3, and 4 pixels, respectively. The key idea of our new screening method is to repeat a local exhaustive search that finds the best binary pattern in small windows of size k × k in a binary image. The experimental results show that the local exhaustive search produces high quality and sharp cluster-dot binary images. We also present an hardware algorithm to accelerate the computation. Our hardware algorithm for a round of the local exhaustive search runs O(k2) clock cycles while the software implementation runs in O(2k2 w2) time, where (2w + 1) × (2w + 1) is the size of Gaussian filter. Thus, from theoretical point of view, our hardware algorithm achieves a speedup factor of O(w2). To show that our hardware algorithm is practically fast, we have implemented it on an FPGA. Our hardware algorithm achieved a speedup factor of up to 229 over the software implementation.
GENERALIZED COUNTERS AND REVERSAL COMPLEXITY
Authors: RAO M. V. PANDURANGA
Published: January 2009

We generalize the definition of a counter and counter reversal complexity and investigate the power of generalized deterministic counter automata in terms of language recognition.
REMARKS ON TWO NONSTANDARD VERSIONS OF PERIODICITY IN WORDS
Authors: BLANCHET-SADRI F. , BROMBERG L. , ZIPPLE K.
Published: January 2009

In this paper, we study some periodicity concepts on words. First, we extend the notion of full tilings which was recently introduced by Karhumäki, Lifshits, and Rytter to partial tilings. Second, we investigate the notion of quasiperiods and show in particular that the set of quasiperiodic words is a context-sensitive language that is not context-free, answering a conjecture by Dömösi, Horváth and Ito.
Plasma Retinol and Prognosis of Postmenopausal Breast Cancer Patients
Authors: Formelli Franca , Meneghini Elisabetta , Cavadini Elena , Camerini Tiziana , Di Mauro Maria G. , De Palo Giuseppe , Veronesi Umberto , Berrino Franco , Micheli Andrea
Published: January 2009

Background: The role of retinol (vitamin A) in breast cancer prognosis has never been investigated in postmenopausal women. We prospectively assessed the long-term prognostic role of retinol plasma levels in a cohort of postmenopausal breast cancer patients.

Patients and Methods: We investigated 208 women self-reported as postmenopausal operated on for T1-2N0M0 breast cancer who participated in a chemoprevention trial as controls and never received chemotherapy or hormone therapy. Plasma samples were collected 3 months (median) after surgery and assayed within 3 weeks for retinol. Minimum and median potential follow-up were 12 and 15 years, respectively. The main analyses were on all women and on a subgroup ages ≥55 years, assumed too old to be in perimenopause. The main end point was breast cancer death. Breast cancer survival was estimated by the Kaplan-Meier method. The hazard ratios of breast cancer death by retinol level were estimated by Cox models stratified for age, where relevant, and recruitment period, and adjusted for tumor size and histology.

Results: At 12 years, patients with low retinol (<2.08 μmol/L, median of distribution) had lower breast cancer survival than those with high retinol (log-rank P = 0.052); the difference was significant for women ≥55 years (log-rank P = 0.006). The adjusted hazard ratios for low versus high retinol were 2.11 (95% confidence interval, 1.08-4.14) for all women and 3.58 (95% confidence interval, 1.50-8.57) for those ≥55 years.

Conclusions: Low plasma retinol strongly predicts poorer prognosis in postmenopausal breast cancer patients. Retinol levels should be determined as part of the prognostic workup. (Cancer Epidemiol Biomarkers Prev 2009;18(1):42–8)
Association and Interactions between DNA Repair Gene Polymorphisms and Adult Glioma
Authors: Liu Yanhong , Scheurer Michael E. , El-Zein Randa , Cao Yumei , Do Kim-Anh , Gilbert Mark , Aldape Kenneth D. , Wei Qingyi , Etzel Carol , Bondy Melissa L.
Published: January 2009

It is generally accepted that glioma develops through accumulation of genetic alterations. We hypothesized that polymorphisms of candidate genes involved in the DNA repair pathways may contribute to susceptibility to glioma. To address this possibility, we conducted a study on 373 Caucasian glioma cases and 365 cancer-free Caucasian controls to assess associations between glioma risk and 18 functional single-nucleotide polymorphisms in DNA repair genes. We evaluated potential gene-gene and gene-environment interactions using a multianalytic strategy combining logistic regression, multifactor dimensionality reduction and classification and regression tree approaches. In the single-locus analysis, six single-nucleotide polymorphisms [ERCC1 3′ untranslated region (UTR), XRCC1 R399Q, APEX1 E148D, PARP1 A762V, MGMT F84L, and LIG1 5′UTR] showed a significant association with glioma risk. In the analysis of cumulative genetic risk of multiple single-nucleotide polymorphisms, a significant gene-dosage effect was found for increased glioma risk with increasing numbers of adverse genotypes involving the aforementioned six single-nucleotide polymorphisms (Ptrend = 0.0004). Furthermore, the multifactor dimensionality reduction and classification and regression tree analyses identified MGMT F84L as the predominant risk factor for glioma and revealed strong interactions among ionizing radiation exposure, PARP1 A762V, MGMT F84L, and APEX1 E148D. Interestingly, the risk for glioma was dramatically increased in ionizing radiation exposure individuals who had the wild-type genotypes of MGMT F84L and PARP1 A762V (adjusted odds ratios, 5.95; 95% confidence intervals, 2.21-16.65). Taken together, these results suggest that polymorphisms in DNA repair genes may act individually or together to contribute to glioma risk. (Cancer Epidemiol Biomarkers Prev 2009;18(1):204–14)
Sampling Strategies for Tissue Microarrays to Evaluate Biomarkers in Ovarian Cancer
Authors: Permuth-Wey Jenny , Boulware David , Valkov Nikola , Livingston Sandra , Nicosia Santo , Lee Ji-Hyun , Sutphen Rebecca , Schildkraut Joellen , Narod Steven , Parker Alex , Coppola Domenico , Sellers Thomas , Pal Tuya
Published: January 2009

Introduction: Tissue microarrays (TMA) enable rapid analysis of biomarkers in large-scale studies involving archival tumor specimens, however, their utility in heterogeneous tumors such as ovarian cancer is limited.

Methods: In this study, immunohistochemical analysis was done on TMAs comprised of epithelial ovarian cancer (EOC) to estimate the prevalence of loss of expression of three mismatch repair proteins. TMAs were initially created using cores sampled from the center of donor tissue blocks from 59 EOC cases. Full sections were subsequently created and levels of expression were compared between tissues sampled from the central portion versus the periphery. Follow-up analyses were done by obtaining cores from the periphery of up to five additional donor blocks per case. A linear mixed model for each protein was used to investigate differences between results from the initial and follow-up blocks.

Results: In the original TMAs created using centrally sampled cores, loss of mismatch repair expression was noted in 17 (29%) of the 59 cases. By comparison, analyses from peripherally sampled cores revealed loss of expression in only 6 of these 17 cases. For each protein, significant differences (P < 0.05) were detected between results from the initial donor block and the majority of the follow-up blocks.

Conclusions: Our investigations, based on EOC, suggest that sampling variability in protein expression may result when TMAs are used. Thus, at least for EOC, it is important to preferentially sample from the periphery of tumor blocks where exposure to tissue fixatives is optimal. (Cancer Epidemiol Biomarkers Prev 2009;18(1):28–34)
TGF-α Expression as a Potential Biomarker of Risk Within the Normal-appearing Colorectal Mucosa of Patients with and without Incident Sporadic Adenoma
Authors: Daniel Carrie R. , Bostick Roberd M. , Flanders William Dana , Long Qi , Fedirko Veronika , Sidelnikov Eduard , Seabrook March E.
Published: January 2009

Background: Transforming growth factor-α (TGF-α), a stimulatory growth factor and member of the epidermal growth factor family, is a mediator of oncogenesis and malignant progression in colorectal carcinogenesis. Limited evidence suggests its utility as a growth-related biomarker of risk for colorectal cancer.

Methods: We measured expression of TGF-α in biopsies of normal-appearing colorectal mucosa using automated immunohistochemistry and quantitative image analysis in a subsample of 29 cases and 31 controls from a colonoscopy-based case-control study (n = 203) of biomarkers of risk for incident sporadic colorectal adenoma. Diet, lifestyle, and medical history were assessed with validated questionnaires.

Results: TGF-α expression in the rectum was 51% higher in cases compared with controls (P = 0.05) and statistically significantly associated with accepted risk factors for colorectal neoplasms (36% lower among nonsteroidal anti-inflammatory drug users, 49% lower among women using hormone replacement therapy, 79% higher among persons with a family history of colorectal cancer).

Conclusions: TGF-α expression in the normal-appearing rectal mucosa shows promise as an early, potentially modifiable biomarker of risk for colorectal cancer. (Cancer Epidemiol Biomarkers Prev 2009;18(1):65–73)
Effects of Menthol on Tobacco Smoke Exposure, Nicotine Dependence, and NNAL Glucuronidation
Authors: Muscat Joshua E. , Chen Gang , Knipe Ashley , Stellman Steven D. , Lazarus Philip , Richie John P.
Published: January 2009

Menthol is a controversial cigarette additive because its physiologic or pharmacologic effects may possibly increase the risk for cancer and its targeted market is the Black community. In a community-based cross-sectional study on 525 Black and White volunteers, we compared levels of urinary and plasma cotinine, plasma thiocyanate, urinary 4-(N-nitrosomethylamino)-1-(3-pyridyl)-1-butanol (NNAL), and its detoxified form (NNAL-Gluc) between menthol and nonmenthol smokers. In regression models that adjusted for daily cigarette intake, no significant differences were observed in the concentration of these biomarkers by menthol status in both races. There was no significant association between high Fagerstrom nicotine dependence scores and the use of menthol cigarettes (odds ratio, 1.1; 95% confidence interval, 0.6-2.0), but an increased risk was observed with smoking a cigarette soon (≤30 minutes) after waking (odds ratio, 2.1; 95% confidence interval, 1.0-3.8). The ratio of NNAL-Gluc to NNAL, a possible indicator of lung cancer risk, was significantly lower in menthol versus nonmenthol smokers. The NNAL-Gluc/NNAL ratio was 34% lower in Whites (P < 0.01) and 22% lower in Blacks. In subsequent human liver microsome studies, menthol inhibited the rate of NNAL-O-glucuronidation and NNAL-N-glucuronidation. Collectively, these results show that menthol does not affect biological exposure to tobacco smoke constituents but indicates that menthol might inhibit the detoxification of the potent lung carcinogen NNAL. (Cancer Epidemiol Biomarkers Prev 2009;18(1):35–41)
Physical Activity and Postmenopausal Breast Cancer: Proposed Biologic Mechanisms and Areas for Future Research
Authors: Neilson Heather K. , Friedenreich Christine M. , Brockton Nigel T. , Millikan Robert C.
Published: January 2009

Convincing evidence now supports a probable preventive role for physical activity in postmenopausal breast cancer. The mechanisms by which long-term physical activity affect risk, however, remain unclear. The aims of this review were to propose a biological model whereby long-term physical activity lowers postmenopausal breast cancer risk and to highlight gaps in the epidemiologic literature. To address the second aim, we summarized epidemiologic literature on 10 proposed biomarkers, namely, body mass index (BMI), estrogens, androgens, sex hormone binding globulin, leptin, adiponectin, markers of insulin resistance, tumor necrosis factor-α, interleukin-6, and C-reactive protein, in relation to postmenopausal breast cancer risk and physical activity, respectively. Associations were deemed “convincing,” “probable,” “possible,” or “hypothesized” using set criteria. Our proposed biological model illustrated the co-occurrence of overweight/obesity, insulin resistance, and chronic inflammation influencing cancer risk through interrelated mechanisms. The most convincing epidemiologic evidence supported associations between postmenopausal breast cancer risk and BMI, estrogens, and androgens, respectively. In relation to physical activity, associations were most convincing for BMI, estrone, insulin resistance, and C-reactive protein. Only BMI and estrone were convincingly (or probably) associated with both postmenopausal breast cancer risk and physical activity. There is a need for prospective cohort studies relating the proposed biomarkers to cancer risk and for long-term exercise randomized controlled trials comparing biomarker changes over time, specifically in postmenopausal women. Future etiologic studies should consider interactions among biomarkers, whereas exercise trials should explore exercise effects independently of weight loss, different exercise prescriptions, and effects on central adiposity. (Cancer Epidemiol Biomarkers Prev 2009;18(1):11–27)
Postmenopausal Levels of Endogenous Sex Hormones and Risk of Colorectal Cancer
Authors: Clendenen Tess V. , Koenig Karen L. , Shore Roy E. , Levitz Mortimer , Arslan Alan A. , Zeleniuch-Jacquotte Anne
Published: January 2009

Observational epidemiologic studies and randomized trials have reported a protective effect of oral hormonal replacement therapy on risk of colorectal cancer. Only one previous prospective study, the Women's Health Initiative Observational Study, has reported on the relationship between endogenous hormones and incident colorectal cancer. Contrary to expectation, the investigators found that women with higher circulating estradiol levels were at increased risk of developing colorectal cancer. We conducted a case-control study nested within the New York University Women's Health Study prospective cohort to evaluate the association between endogenous levels of estrone, estradiol, and sex hormone–binding globulin (SHBG) with risk of colorectal cancer. We measured hormones and SHBG in serum samples collected at enrollment from a total of 148 women who subsequently developed colorectal cancer and 293 matched controls. Circulating estrone levels were positively associated with risk of colorectal cancer: The odds ratio for the highest versus lowest quartile of estrone was 1.8 (95% confidence interval, 1.0-3.3). We found a nonsignificant inverse association between SHBG and colorectal cancer, which disappeared after adjusting for body mass index. We did not find an association between estradiol and colorectal cancer risk, but we cannot rule out a potential association because of substantial laboratory error in the measurement. Our results suggest that endogenous estrone is associated with increased risk of colorectal cancer in postmenopausal women. (Cancer Epidemiol Biomarkers Prev 2009;18(1):275–81)
Insulin-like Growth Factor-1- and Interleukin-6-related Gene Variation and Risk of Multiple Myeloma
Authors: Birmann Brenda M. , Tamimi Rulla M. , Giovannucci Edward , Rosner Bernard , Hunter David J. , Kraft Peter , Mitsiades Constantine , Anderson Kenneth C. , Colditz Graham A.
Published: January 2009

Insulin-like growth factor (IGF)-1 and interleukin (IL)-6 promote the proliferation and survival of multiple myeloma cells. Variation in genes related to IGF-1 and IL-6 signaling may influence susceptibility to multiple myeloma. To assess their etiologic role, we examined the association of 70 tagging single nucleotide polymorphisms (SNP) in seven IGF-1 and three IL-6 pathway genes with multiple myeloma risk in two prospective cohorts, the Nurses' Health Study and the Health Professionals Follow-up Study. Among the participants who provided DNA specimens, we identified 58 women and 24 men with multiple myeloma and matched two controls per case. We used multivariable logistic regression models to assess the association of the SNPs or tagged haplotypes with multiple myeloma risk. Several SNPs had suggestive associations with multiple myeloma based on large odds ratios (OR), although the corresponding omnibus P values were not more than nominally significant (i.e., at P < 0.05). These SNPs included rs1801278 in the gene encoding insulin receptor substrate-1 [IRS1; C/T versus C/C genotypes; OR, 4.3; 95% confidence interval (CI), 1.5-12.1] and three IL-6 receptor SNPs: rs6684439 (T/T versus C/C; OR, 2.9; 95% CI, 1.2-7.0), rs7529229 (C/C versus T/T; OR, 2.5; 95% CI, 1.1-6.0), and rs8192284 (C/C versus A/A; OR, 2.5, 95% CI, 1.1-6.0). Additional SNPs in genes encoding IGF-1, IGF binding protein-2, IRS2, and gp130 also showed suggestive associations with multiple myeloma risk. We conducted a large number of statistical tests, and the findings may be due to chance. Nonetheless, the data are consistent with the hypothesis that IGF-1- and IL-6-related gene variation influences susceptibility to multiple myeloma and warrant confirmation in larger populations. (Cancer Epidemiol Biomarkers Prev 2009;18(1):282–8)
Acute versus Chronic Myocardial Ischemia: A Differential Biological Profile Study
Authors: Sagastagoitia José Domingo , Sáez Yolanda , Vacas Marta , Narváez Idoia , Sáez de Lafuente Jesús Pablo , Molinero Enrique , Escobar Antonio , Lafita Manuel , Iriarte José Antonio
Published: January 2009

Objective: To determine the possible differences in lipid, thrombogenic and inflammatory marker concentrations and the presence of chronic and acute coronary artery disease (stable and unstable angina, respectively), comparing them with a group of control patients with normal coronary arteries. Material and Methods: This prospective cohort study included 125 patients with unstable angina, 189 with stable angina and a control group of 83 patients with normal coronary arteries. Marker concentrations were measured in all 3 groups. Logistic regression analysis was performed to determine whether such factors could predict unstable or stable angina. Results: Lipid parameter concentrations were similar in the 2 coronary disease groups and significantly lower than in controls. Haemostatic and inflammatory marker concentrations were higher in patients with coronary disease, but were statistically significant only when comparing unstable angina patients with normal controls. Unstable angina patients had significantly higher levels of lipoprotein (a) [Lp(a)], fibrinogen, C-reactive protein (CRP) and leucocytes. Multiple logistic regression analysis showed that CRP (OR 2.635, 95% CI 1.417–4.898), smoking (OR 3.416, 95% CI 1.773–6.584), leucocytes (OR 2.034, 95% CI 1.079–3.836) and Lp(a) (OR 2.269, 95% CI 1.188–4.334) were independent risk factors of unstable versus stable angina. Conclusions: Patients with unstable angina present a more atherogenic profile than patients with stable angina. Together with smoking, elevated Lp(a), CRP and leucocyte concentrations proved to be associated with the presence of unstable angina.
Acute Complete Splenic Infarction in a Patient with Hirschsprung’s Disease and Literature Review of Complete Splenic Infarction
Authors: Guler N. , Yapici O. , Erdem D. , Ogur G. , Ozatli D. , Bakir T.
Published: January 2009

Here we report a case of Hirschsprung’s disease presenting with acute complete splenic infarction due to thrombus in the splenic vena. MTHFR C677T (methylenetetrahydrofolate) gene homozygote mutation was a risk factor for thrombosis. According to our knowledge, this is the first report for a Hirschsprung’s disease patient with acute complete splenic infarct due to isolated splenic vein thrombosis accompanied by MTHFR C677T gene homozygote mutation.
A Novel TP53 Germline Mutation in a Family with a History of Multiple Malignancies: Case Report and Review of the Literature
Authors: Agarwalla Pankaj K. , Dunn Ian F. , Turner Christopher D. , Ligon Keith L. , Schneider Katherine A. , Smith Edward R.
Published: January 2009

Objective: Choroid plexus carcinoma (CPC) has been associated with TP53 germline mutations and Li-Fraumeni syndrome (LFS). We describe our finding of a novel germline mutation in the TP53 gene in a family with multiple malignancies and in association with a child presenting with CPC. Method: An 8-month-old male presented with seizure-like activity; imaging disclosed a 1.5-cm left ventricular mass confirmed to be CPC intra- and postoperatively. Family history was significant for a half-sister who died of a primary CNS sarcoma and a paternal grandmother negative for BRCA1, BRCA2, MLH1, and MSH2 mutations with multiple (>6) LFS spectrum malignancies. Results: Familial TP53 testing revealed an A→T substitution at DNA position 13071, creating a deleterious Asn→Ile substitution at amino acid 131 in exon 5. Conclusion: Physicians treating patients with CPC should be attuned to reviewing family history for risk factors suggestive of genetic cancer syndromes such as LFS. These syndromes markedly influence both the patient and family members and may alter postoperative treatment regimens.
Nicotinamide Cooperates with Retinoic Acid and 1,25-Dihydroxyvitamin D3 to Regulate Cell Differentiation and Cell Cycle Arrest of Human Myeloblastic Leukemia Cells
Authors: Shen Miaoqing , Yen Andrew
Published: January 2009

Nicotinamide, the amide derivative of vitamin B3, cooperates with retinoic acid (RA), a form of vitamin A, and 1,25-dihydroxyvitamin D3 (D3), to regulate cell differentiation and proliferation of human myeloblastic leukemia cells. In human myeloblastic leukemia cells, RA or D3 are known to cause MAPK signaling leading to myeloid or monocytic differentiation and G0 cell cycle arrest. In this process, RA or D3 induces the early expression of CD38, a receptor that causes ERK signaling and propels further differentiation. Our study demonstrates that nicotinamide in combination with RA or D3 affected induced expression levels of CD38, CD11b and CD14, suggesting a cooperative function of nicotinamide and RA or D3. Nicotinamide transiently retarded the initial RA- or D3-induced expression of CD38, which subsequently reached the same nearly 100% expression. Nicotinamide induced ERK activation and further enhanced the RA-induced ERK activation, but the D3-induced ERK activation was diminished by nicotinamide, although levels still exceeded those induced by RA, suggesting lineage-specific nicotinamide responses. Nicotinamide enhanced both RA- and D3-induced CD11b expression, inducible oxidative metabolism, and G0 cell cycle arrest, accelerating their induced occurrence in all instances. Consistent with this, the RA- or D3-induced downregulation of PARP was enhanced by nicotinamide. Nicotinamide thus regulated RA- or D3-induced differentiation and G0 arrest, causing a transient delay in certain early aspects of the progression to terminal differentiation but ultimately accelerating the occurrence of terminally, functionally differentiated G0 cells.
Selective Killing of Leukemia and Lymphoma Cells Ectopically Expressing hCGβ by a Conjugate of Curcumin with an Antibody against hCGβ Subunit
Authors: Vyas Hemant K. , Pal Rahul , Vishwakarma Ram , Lohiya Nirmal K. , Talwar G.P.
Published: January 2009

Objective: A variety of cancers ectopically express human chorionic gonadotropin beta (hCGβ). Patients harboring such cancers have poor prognosis and adverse survival. A recombinant chimeric antibody, cPiPP, exhibiting high affinity and specificity for hCGβ/hCG was engineered. This study was designed to determine whether this antibody alone or conjugated to curcumin can selectively kill tumor cells expressing hCGβ. Experimental Design: The study was carried out on MOLT-4 and U-937 cells expressing hCGβ and on peripheral blood leukocytes of acute myeloid leukemia (AML) patients. The anticancerous compound curcumin was conjugated to cPiPP. The binding of cPiPP and cPiPP-curcumin conjugate to cells was studied by flow cytometry and cytotoxicity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), FACS with propidium iodide staining, trypan blue exclusion assay and microscopy. Results: The antibody did not impair the growth of MOLT-4 and U-937 cells in culture. Its conjugate with curcumin, however, was lethal to both cell lines. The immunoconjugate killed tumor cells bearing the CD33 marker of an AML patient expressing hCGβ but did not have a similar action on cells of another AML patient with the CD13 marker but who was negative for hCGβ. Conclusion: A humanized antibody against hCGβ linked to curcumin has potential for therapy of hCGβ-expressing tumors.
Core Design for Energy Absorption in Sandwich Composites
Authors: Stapleton Scott E. , Adams Daniel O.
Published: January 2009

To achieve high energy absorption under edgewise compression loading, sandwich composites must experience a progressive failure that includes compression failure of the facesheets. This investigation focused on sandwich core design for energy absorption through the use of failure mode maps. Predictive models for global buckling, facesheet wrinkling, and facesheet compression failure were used to construct failure mode maps as a function of sandwich core thickness and density. Predicted failure loads and initial failure modes were found to be in good agreement with results from edgewise compression testing. Sandwich configurations experiencing facesheet compression failure as the initial failure mode were found to produce the highest energy absorption. These results suggest that sandwich composites may be designed for enhanced energy absorption through the proper selection of core materials and geometries.
Publishing in the Journal of Travel Research
Authors: Perdue Richard R. , Meng Fang , Courtney Jennifer
Published: January 2009

This article reports on a study that examined manuscript and review data for the Journal of Travel Research ( JTR). Two sets of data were examined to address the question “what are the key issues affecting acceptance and/or rejection of manuscripts submitted for publication in JTR?” Manuscripts reviewed for publication in JTR are sent to three editorial board members for review. Reviewers are asked to (a) quantitatively rate the manuscript on a review form and (b) provide qualitative comments to the authors articulating their perspectives of the manuscript along with concerns and constructive recommendations. Stratified, random samples of these quantitative ratings and qualitative comments for both manuscripts that were subsequently rejected and manuscripts that were ultimately accepted for publication provided the data for this study. The article presents these data and concludes with recommendations for authors.
Experimental Analysis of Sample-Based Maps for Long-Term SLAM
Authors: Biber Peter , Duckett Tom
Published: January 2009

This paper presents a system for long-term SLAM (simultaneous localization and mapping) by mobile service robots and its experimental evaluation in a real dynamic environment. To deal with the stability-plasticity dilemma (the trade-off between adaptation to new patterns and preservation of old patterns), the environment is represented by multiple timescales simultaneously (five in our experiments). A sample-based representation is proposed, where older memories fade at different rates depending on the timescale and robust statistics are used to interpret the samples. The dynamics of this representation are analyzed in a five-week experiment, measuring the relative influence of short- and long-term memories over time and further demonstrating the robustness of the approach.
Review: Current status of therapy in autoimmune liver disease
Authors: Hirschfield Gideon M. , Al-Harthi Nadya , Heathcote E. Jenny
Published: January 2009

Therapeutic strategies for autoimmune liver diseases are increasingly established. Although proportionately uncommon, specialist centers have with time refined the best approaches for each disease, based on an improved understanding of the spectrum of presentation. The major treatment aims are to prevent end-stage liver disease and its associated complications. As a result of drugs such as ursodeoxycholic acid, predniso(lo)ne and azathioprine, both primary biliary cirrhosis and autoimmune hepatitis are now less commonly indications for liver transplantation. Unfortunately, the same inroads in treatment efficacy have as yet not been made for primary sclerosing cholangitis, although the recognition that a subset of patients may have a treatable secondary sclerosing cholangitis (IgG4 related) is helping a proportion. With better biological understanding, more specific interventions are expected that will benefit all those with autoimmune liver diseases.
Review: Current status of therapy for hepatocellular carcinoma
Authors: Corey Kathleen E. , Pratt Daniel S.
Published: January 2009

The incidence of hepatocellular carcinoma (HCC) is increasing worldwide. A multidisciplinary approach is required for its management. Screening high-risk patients allows for earlier diagnosis and the use of potentially curative therapies. Current recommendations for HCC screening for patients with cirrhosis are an abdominal ultrasound and serum alpha fetoprotein level every 6 to 12 months. Treatment choice depends on tumor stage, liver function and the patient's overall functional status. Curative therapies include surgical resection, liver transplantation (LT), transarterial chemoembolization, and radiofrequency ablation (RFA). Surgical resection, either primary resection or LT, is the treatment most likely to result in cure of HCC. Which option to pursue is based on multiple factors. LT has the potential benefit of treating both HCC and the underlying cirrhosis; however, long wait times incur the risk of tumor progression. Firm recommendations regarding the role of living donor LT for HCC are not yet possible because of conflicting data. HCC recurrence after LT is 8—11% and several adjuvant therapies have been investigated to reduce this. Bridging therapy and tumor downsizing are techniques that also may be considered to deal with long waiting periods and qualification for LT, respectively. If neither LT nor primary resection is possible, loco-regional therapies such as RFA and TACE should be considered. Systemic chemotherapies have proved disappointing for the treatment of HCC; however, newer targeted therapies such as sorafenib and cetuximab have provided new hope for the future.
Review: Eradication of H. pylori infection: the challenge is on if standard therapy fails
Authors: Bohr Ulrich R.M. , Malfertheiner Peter
Published: January 2009

The recommended standard triple therapy for Helicobacter pylori infection, consisting of a proton pump inhibitor, clarithromycin and amoxicillin or metronidazole, can reach eradication rates in over 90%. However, in recent years resistance to antibiotics has increased and eradication rates have declined. Approximately one in five patients need a second-line therapy because eradication therapy fails. Second-line treatment with a bismuth-based quadruple therapy leads to satisfactory eradication rates, but bismuth is not available in many countries. Modern second- and third-line treatments can only be successful if they are adapted to the current resistance situation and they need to evolve continuously. Moreover, pharmacodynamic effects due to polymorphisms of the cytochrome P450 system are important. Because therapy adherence is significantly associated with therapy success, modern regimens if possible should be easy to take and well tolerated. In recent years, various novel salvage-therapy regimens have been investigated that significantly improve treatment options.
Induced-current-generated System Using the Chemomechanical Transduction at a Nitrobenzene/Water Interface
Authors: Matsushita Sachiko , Yoshida Kaori , Sato Tetsuya , Suga Yoshihiro
Published: January 2009

An induced-current-generated system using the nonequilibrium phenomena of water, nitrobenzene, and trimethylstearylammonium chloride is proposed. A nitrobenzene droplet spontaneously carried a small magnet around a coil, resulting in the induced current. Incidentally, we observed that the spontaneous rotation occurred without any contact with a glass substrate.
The First Organic Radical Compounds Exhibiting n-Type FET Properties
Authors: Aoki Kazunori , Akutsu Hiroki , Yamada Jun-ichi , Nakatsuji Shin’ichi , Kojima Takahiro , Yamashita Yoshiro
Published: January 2009

A couple of naphthalenediimide derivatives carrying TEMPO radicals were found to exhibit n-type FET with mobilities up to 2.6×10−5 cm2/V·s as the first examples of spin-carrying acceptor systems while no FET property could be discerned in the corresponding naphthaleneimide derivative.