bluuebunny/crossref_metadata_2025_split huggingface dataset:
Subharmonic Oscillations of Moored Floating Cranes
Authors: Clauss G.F. , Vannahme M. , Ellerman K. , Kreuzer E. 
Published: March 2009

Abstract
The paper presents a comparative study of the operation capabilities offloating cranes, i.e. barge, ship and semisubmersible vessel with hanging load. Over a wide range of applications the dynamic behaviour of moored floatingcranes can be treated as being linear. Under certain conditions, however, thecoupled system of floating structure and swinging load shows different linearand nonlinear phenomena:in-phase and anti-phase load oscillations mutually coupled tointerdependent transverse and angular resonance motions of the cranevesselsubharmonic motions of the vessel due to nonlinear mooringcharacteristics.
In such cases a safe heavy-lift operation cannot be guaranteed since thelinear methods underestimate the occurring loads and motions.
Time series and bifurcation analysis reveal a coexistence of subharmonicoscillations, i.e. period 2 (P-2) or period 3 (P-3) motions with significantlyincreased amplitudes compared to a harmonic linear mode (P-1) in case of anonlinear mooring characteristic. Surge and pitch motion of the floating vesselas well as the coupled motion of the swinging load are substantially influencedby nonlinear restoring forces. High peaks in the mooring line forces occur dueto increased surge amplitudes. The analysis identifies the significance of keyparameters and reveals how the mooring system design can be adjusted to avoidcritical conditions.

Introduction
Floating cranes play an increasingly important role in the operation ofoffshore installations. Basically, three different types of floating cranes aredistinguished (Fig. 1):Barges with hinged shearlegs located at the bow of pontoon shaped hulls, operating in sheltered waters of harbours where waves are relatively low, andin offshore regions at moderate weather conditions.Ships for crane (and pipelaying) operations equipped with a revolving craneat the stern. Their development started in the early Seventies, when first oiland gas was produced from fields in harsher environment of the North Sea. Advantages of monohulls are higher transit speed, associated with lowermobilizing costs.Semisubmersibles with two revolving cranes. In 1978, Heerema built thefirst SSCVs - Balder and Hermod. Since then vessels with tandem lift capacitiesof 12.000 t and 14.000 t have been put into operation. The advantages ofsemisubmersible vessels like Heeremac's Thialf (formerly DB 102) or Saipem's S7000 are favorable seakeeping behaviour and an immense deckload capacity ascompared to older and smaller crane ships.
Data Integration for Velocity Modeling and Depth Conversion, Trinidad and Tobago
Authors: Day Ron A. , Burch Tom , Lehmann Christoph , Hoffman Karen S. 
Published: March 2009

Abstract
Gas-bearing reservoirs southeast of Trinidad are often difficult torepresent geometrically in spite of excellent quality 3-D seismic dataavailable in the area. Developmental challenges of this field include:multiple pay sands (about 20);fault-induced compartmentalization;broad low-relief hydrocarbon accumulations; andcomplex velocityvariations. Variations in facies and burial rates in addition to shallow and localized gas-bearing sands give rise to a complex subsurface velocity field.
The localized gas-bearing sands manifest seismically as pronounced "gas sags". Accurate depth representation of proven and non-proven resources wasaccomplished using a minimum number of seismic surfaces (the five besthorizons), all mappable faults, a robust velocity model (for depth conversion), and well data to build a depth model of all of the sands and shales in thesubsurface. Below the shallow gas-bearing sands, initial efforts were notadequate to completely remove the gas sags, which impact over 25% of the studyarea. To accomplish final depth reconstruction, a number of seismic traverseswere interpreted through wells which pass through the shallow gas-bearingsands. These lines were depth converted and used to remove the gas sag wherethe velocity model was inadequate due to incorrect imaging of the seismic data. This was an iterative process which made use of geospatial data (isopachs, welldata, fault displacements, etc.) and was tested against all geophysical data(seismic interpretation, amplitudes, and velocity data). The result was a modelwhich not only added 0.5 TCF of proven resources, but also explained thetrapping mechanism responsible for gas accumulations in multiple reservoircompartments.

Geologic Setting
The Parang field, part of exploration and production license 120, lies 50miles southeast of the coast of Trinidad (Fig. 1). The field is located in the Columbus basin, which formed between the Caribbean and South American plates. The Miocene to Pleistocene reservoir sands and intercalated shales weredeposited in a variety of depositional environments along the ancestral Orinocodelta. Sedimentary rocks deposited on basin floor to slope fans comprise thelower part of the stratigraphic section. The sands and shales in the middle andupper part of the section were deposited in a paralic setting ranging fromprograding shore facies to a fluvial and transitional barrier complex. Thesource rock is assumed to be early Miocene and/or late Cretaceous in age.
The Physical Chemistry of Wax, Hydrates, and Asphaltene
Authors: Ellison B.T. , Gallagher C.T. , Frostman L.M. , Lorimer S.E. 
Published: March 2009

Abstract
Wax, hydrates, and asphaltenes are the three major threats to flow assurancethat must be assessed by design teams. These potential problems can dramatically change system selection and operational procedures. If one of themis discovered after the system is under construction or worse after first oilthen the whole project may be at risk. Each solid must be well understood byengineers so they can neutralize the threats to system uptime that result frompoor solids management. This paper focuses on the problems posed by, and the system implications of, wax, hydrates, and asphaltenes.

Introduction
Flow assurance in subsea systems focuses on preventing solid deposits fromblocking the flow path. The principle solids of concern are wax and hydrates. Sometimes scale and asphaltenes are also a concern. For a given reservoir fluidthese solids precipitate at certain combinations of pressure and temperature. Precipitated solids are often carried downstream slurried in the fluid; however precipitated solids can also deposit on the walls of the production equipment, which ultimately causes plugging and flow stoppage. Control of this blockage isthe essence of "flow assurance". Solids control strategies involve keeping thesystem pressure and temperature in a region where the solids are unstable(thermodynamic control) or controlling the conditions of solids formation sothat deposits do not form (kinetic control) or allowing solids to deposit, thenperiodically removing them (mechanical control).
This paper focuses on the thermodynamic and kinetic behavior of wax, hydrates and asphaltenes in reservoir fluids. The emphasis is on solidsbehavior in subsea systems. So, for each solid we describe the phase envelope, rate of solid formation and system implications. We also describephysicochemical factors important in solids removal. This is not acomprehensive review of the solids but we will describe their behavior wellenough so that the reader can understand why subsea systems are designed andoperated as they are.

Wax
Paraffinic hydrocarbon fluids can cause a variety of problems in aproduction system ranging from solids stabilized emulsions to a gelledflowline. Problems caused by wax occur when the fluid cools from reservoirconditions and wax crystals begin to form. The temperature at which crystals first begin to form is called the cloud point. At temperatures below the cloudpoint, crystals begin to form and grow. Crystals may form either in the bulkfluid forming particles that are transported along with the fluid or deposit on a cold surface where the crystals will build-up and foul the surface.
The Dynamics of a Flexible Jackup Transported in a Seaway
Authors: Fu Y. , Price W.G. , Temarel P. 
Published: March 2009

Abstract
Based on a three dimensional hydroelasticity theory, the responses (i.e.displacements, distortions, bending moments, shearing forces, stresses) at anyposition in a flexible jack-up structure are assessed. The transported rig iseither carried dry or towed wet in a unidirectional or confused seaway. Calculated response spectra and statistical measures are presented toillustrate the influence of barge/jack-up flexibility, sea conditions, wavespreading etc.

Introduction
The safe transportation of offshore structures from one exploration site toanother is an important operation which these designs must withstand, even whenundertaken in unexpected severe sea conditions. For mobile offshore drillingunits, two alternative modes of transportation may be considered. These areusually referred to as 'wet' and 'dry' tows. In the wet tow, the self floatingstructure is either towed by tugs or self-propelled whilst in a dry tow thestructure is carried on a heavy lift vessel or a flat top barge. The selectedmode of tow depends on the availability of suitable vessels, the dimensions andcharacteristics of the structure, the distance of the tow, expected seaconditions, etc.
To ensure maximum safety, a detailed knowledge of the behaviour of thedynamic responses of the structure to the expected wave loadings is essentialso that the viability of the transportation and mode of operation to differentenvironmental conditions may be assessed. However, the evaluation of theresponse characteristics of any marine structure relies on a chosenmathematical model with its inherent built in set of assumptions. These mayrely on particular physical attributes possessed by the structure i.e. large, slender, shallow draft etc. or assumptions introduced to simplify the analysiswhich may not truly reflect the correct physical nature of the structure. Forexample, it is not uncommon to treat structures as rigid bodies whereas inreality all structures are flexible possessing distributions of mass andstructural stiffness throughout their forms. The implications of theseassumptions have been discussed elsewhere and significant qualitative andquantitative differences may occur between the predicted responses depending onthe assumptions introduced. This investigation is continued in this paper withreference to the dry transportation of a flexible jack-up structure inprescribed irregular seaways.
Overview of High‐Throughput Screening
Authors: Entzeroth Michael , Flotow Horst , Condron Peter 
Published: March 2009

AbstractHigh‐throughput screening (HTS) is a key process used in drug discovery to identify hits from compound libraries that may become leads for medicinal chemistry optimization. This updated overview discusses the utilization of compound libraries, compounds derived from combinatorial and parallel synthesis campaigns and natural product sources; creation of mother and daughter plates; and compound storage, handling, and bar coding in HTS. The unit also presents an overview of established and emerging assay technologies (i.e., time‐resolved fluorescence, fluorescence polarization, fluorescence‐correlation spectroscopy, functional whole cell assays, and high‐content assays) and their integration in automation hardware and IT systems. This revised unit provides updated descriptions of state‐of‐the‐art instrumentation and technologies in this rapidly changing environment. The section on assay methodologies now also covers enzyme complementation assays and methods for high‐throughput screening of ion channel activities. Finally, a section on criteria for assay robustness is included discussing the Z′‐factor, which is now a widely accepted criterion for evaluation and validation of high throughput screening assays. Curr. Protoc. Pharmacol. 44:9.4.1‐9.4.27. © 2009 by John Wiley & Sons, Inc.
HPLC determination of acidic d‐amino acids and their N‐methyl derivatives in biological tissues
Authors: Tsesarskaia Mara , Galindo Erika , Szókán Gyula , Fisher George 
Published: March 2009

Abstractd‐Aspartate (d‐Asp) and N‐methyl‐d‐aspartate (NMDA) occur in the neuroendocrine systems of vertebrates and invertebrates, where they play a role in hormone release and synthesis, neurotransmission, and memory and learning. N‐methyl‐d‐glutamate (NMDG) has also been detected in marine bivalves. Several methods have been used to detect these amino acids, but they require pretreatment of tissue samples with o‐phthaldialdehyde (OPA) to remove primary amino acids that interfere with the detection of NMDA and NMDG. We report here a one‐step derivatization procedure with the chiral reagent N‐α‐(5‐fluoro‐2,4‐dinitrophenyl)‐(d or l)‐valine amide, FDNP‐Val‐NH2, a close analog of Marfey's reagent but with better resolution and higher molar absorptivity. The diastereomers formed were separated by HPLC on an ODS‐Hypersil column eluted with TFA/water–TFA/MeCN. UV absorption at 340 nm permitted detection levels as low as 5–10 pmol. d‐Asp, NMDA and NMDG peaks were not obscured by other primary or secondary amino acids; hence pretreatment of tissues with OPA was not required. This method is highly reliable and fast (less than 40 min HPLC run). Using this method, we detected d‐Asp, NMDA and NMDG in several biological tissues (octopus brain, optical lobe and bucchal mass; foot and mantle of the mollusk Scapharca broughtonii), confirming the results of other researchers. Copyright © 2009 John Wiley & Sons, Ltd.
Extraction and analysis of colourful eggshell pigments using HPLC and HPLC/electrospray ionization tandem mass spectrometry
Authors: Gorchein A. , Lim C. K. , Cassey P. 
Published: March 2009

AbstractThe literature on the pigments of avian eggshells is critically reviewed. Methods using methanolic sulfuric acid or hydrochloric acid to extract eggshell pigments are unsuitable to detect the occurrence of zinc protoporphyrin or zinc biliverdin because they demetallate these compounds. Extraction methods are described here using EDTA and acetonitrile–acetic acid or acetonitrile–dimethyl sulfoxide, which do not demetallate zinc protoporphyrin. Such extracts were prepared from eggshell of the common nighthawk, Chordeiles minor, and from another six bird species. Protoporphyrin and biliverdin were identified and fully characterized by HPLC/electrospray ionization tandem mass spectrometry (HPLC/ESI‐MS/MS) in all samples, but none contained zinc protoporphyrin. The zinc complex of biliverdin, claimed to be an additional pigment responsible for eggshell background colours, was labile to EDTA and acid pH and if occurring naturally could not be extracted intact by the published or the modified protocols. An explanation is advanced for the exceptional report that all porphyrins from uroporphyrin to protoporphyrin were found in eggshells of the fowl Gallus domesticus. Copyright © 2009 John Wiley & Sons, Ltd.
Development and validation of a highly sensitive and robust LC‐ESI‐MS/MS method for simultaneous quantitation of simvastatin acid, amlodipine and valsartan in human plasma: application to a clinical pharmacokinetic study
Authors: Ramani Addepalli V. , Sengupta Pinaki , Mullangi Ramesh 
Published: March 2009

AbstractA high‐throughput, simple, highly sensitive and specific LC‐MS/MS method has been developed for simultaneous estimation of simvastatin acid (SA), amlodipine (AD) and valsartan (VS) with 500 µL of human plasma using deuterated simvastatin acid as an internal standard (IS). The API‐4000 LC‐MS/MS was operated under the multiple reaction‐monitoring mode (MRM) using electrospray ionization. The assay procedure involved precipitation of SA, AD, VS and IS from plasma with acetonitrile. The total run time was 2.8 min and the elution of SA, AD, VS and IS occurred at 1.81, 1.12, 1.14 and 1.81 min, respectively; this was achieved with a mobile phase consisting of 0.02 mammonium formate (pH 4.5):acetonitrile (20:80, v/v) at a flow rate of 0.50 mL/min on an X‐Terra C18column. A linear response function was established for the range of concentrations 0.5–50 ng/mL (r > 0.994) for VS and 0.2–50 ng/mL (r > 0.996) for SA and AD. The method validation parameters for all three analytes met the acceptance as per FDA guidelines. This novel method has been applied to human pharmacokinetic study. Copyright © 2009 John Wiley & Sons, Ltd.
A sensitive and specific liquid chromatography/tandem mass spectrometry method for determination of echinacoside and its pharmacokinetic application in rats
Authors: Yang Hao , Wang Guangji , Hao Haiping , Tu Pengfei , Jiang Yong , Wang Qiong , Zhang Yan , Zheng Chaonan , Wang Yuxin , Dai Liang 
Published: March 2009

AbstractA rapid and sensitive method based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) for the determination of echinacoside in rat plasma was established and fully validated. A single step of liquid–liquid extraction with n‐butanol was utilized. Chromatographic separation of the analyte and the internal standard (IS), chlorogenic acid, from the sample matrix was performed using a Capcell‐MG C18 analytical column (100 2.0 mm × 5 µm), with a gradient of acetonitrile and water containing 0.1% acetic acid as the mobile phase. Detection was performed on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization source operated in negative ion selected reaction monitoring mode. The method was linear in the concentration range 10–2500 ng/mL. The deviations of both intra‐ and inter‐day precisions (RSD) were 7.1% and the assay accuracies were within 99.2–106.5%. Echinacoside proved to be stable during sample storage, preparation and analysis when an antioxidant solution was used. The method was successfully applied to a pharmacokinetic study in rats after an intragastric administration of echinacoside (100 mg/kg). With the lower limit of quantification at 10 ng/mL, this method proved to have sufficient selectivity, sensitivity and reproducibility for the pharmacokinetic study of echinacoside. Copyright © 2009 John Wiley & Sons, Ltd.
Effects of cholesterol and docosahexaenoic acid on cell viability and (Ca2+)i levels in acutely isolated mouse thymocytes
Authors: Sandal Suleyman , Tuneva Jelena , Yilmaz Bayram , Carpenter David O. 
Published: March 2009

AbstractWe investigated the effects of lipids on thymocyte function. The effects of application of cholesterol or docosahexaenoic acid (DHA), a C22, omega‐3 (n‐3) polyunsaturated fatty acid (PUFA), on viability and intracellular calcium concentrations of acutely isolated mouse thymocytes were investigated using flow cytometry. Cholesterol (100 µM) caused significant cell death after 30–60 min whether or not calcium was present in the medium. Cell death was associated with an elevation of intracellular calcium whether or not calcium was present in the extracellular medium. However, the elevation of calcium concentration was not responsible for the cell death since calcium levels in the presence of ionomycin rose higher without significant cell death. DHA had similar actions but was more potent, causing significant cell death and elevation of calcium concentration within 5 min at 1 µM. In the absence of extracellular calcium 1 µM DHA caused 100% cell death within 15 min. Linolenic acid, a C18 omega‐3 fatty acid also caused cytotoxicity at low concentrations whether or not albumin was present, but omega‐6 or saturated C22 fatty acids were much less effective. These observations demonstrate that thymocyte viability is very sensitive to acute exposure to low concentrations of omega‐3 fatty acids. Copyright © 2009 John Wiley & Sons, Ltd.
Coping strategies used by hypersexual patients to defend against the painful effects of shame
Authors: Reid Rory C. , Harper James M. , Anderson Emily H. 
Published: March 2009

AbstractThis article reports the findings of a study investigating coping strategies used by hypersexual patients (n = 71), compared with a control group (n = 73), in their attempts to defend against shame. Coping strategies were measured using the Compass of Shame Scale (CoSS) and hypersexual behaviour was measured by the Hypersexual Behavior Inventory (HBI). A multivariate analysis of variance of between‐group differences was significant, and examination of post hoc univariate tests revealed that the sample of hypersexual patients defended against shame with higher levels of withdrawal and higher tendencies to attack self and others when compared with the control group. The effect sizes of these differences were moderate to large. A categorical analysis of the patient group indicated that the greatest percentages of elevated shame scores were clustered on the Withdrawal and Attack Self subscales of the CoSS. Between‐group differences on the Avoidance subscale of the CoSS were not significant. The results of this study are discussed as they pertain to clinical practice, and future recommendations for research are offered. Copyright © 2009 John Wiley & Sons, Ltd.
Corporate social responsibility in Malaysia – experts' views and perspectives
Authors: Lu Jye Y. , Castka Pavel 
Published: March 2009

AbstractThe field of corporate social responsibility (CSR) has grown exponentially in the last decade and is gradually becoming a global trend. Companies are now expected to take explicitly into account all aspects of their performance, i.e., not just their financial results, but also their social and environmental performance. Therefore more organizations are now engaged in serious efforts to define and integrate CSR into all aspects of their businesses. The aim of our study is to understand this trend in Malaysia and specifically to investigate (i) The status of CSR in Malaysia; (ii) Different CSR practices in Malaysia; and (iii) Future diffusion of CSR in Malaysia. To answer these questions, we have conducted interviews with Malaysian leading experts in CSR. Our results suggests that the key issues in the journey toward wider diffusion and acceptance of CSR in Malaysia include current confusion over the meaning of CSR, the prevalent use of CSR as a PR tool, mandatory versus voluntary CSR and the role the National Mirror Committee of ISO/TMB/WG SR in this process. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
The effect of xanthorrhizol on the expression of matrix metalloproteinase‐1 and type‐I procollagen in ultraviolet‐irradiated human skin fibroblasts
Authors: Oh Hyun‐In , Shim Jae‐Seok , Gwon Song‐Hui , Kwon Ho‐Jeong , Hwang Jae‐Kwan 
Published: March 2009

AbstractMatrix metalloproteinases (MMPs) are key regulators of the skin photoaging process that is set in motion by exposure to ultraviolet (UV) irradiation. This skin damage results from UV‐induced generation of reactive oxygen species, which are associated with upregulation of MMPs and decreased collagen synthesis. We investigated the effects of xanthorrhizol, isolated from Curcuma xanthorrhiza, on the expression of MMP‐1 and type‐I procollagen in UV‐irradiated human skin fibroblasts. Fibroblasts cultured in the presence or absence of purified xanthorrhizol or C. xanthorrhiza extract were irradiated with UV (20 mJ/cm2), and MMP‐1 and type‐I procollagen levels were measured using Western blot analysis. Xanthorrhizol (0.001–0.1 µM) and C. xanthorrhiza extract (0.01–0.5 µg/mL) induced a significant, dose‐dependent decrease in the expression of MMP‐1 protein, and increased the expression of type‐1 procollagen. At a concentration of 0.1 µM, xanthorrhizol nearly completely abrogated MMP‐1 expression. The MMP‐1‐suppressing and type‐1 procollagen‐inducing effects of xanthorrhizol treatment were greater than those of epigallocatechin 3‐O‐gallate (EGCG), which is known to be a natural anti‐aging agent. These results suggest that xanthorrhizol is a potential candidate for the prevention and treatment of skin aging. Copyright © 2009 John Wiley & Sons, Ltd.