bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of clinical, microbiologic, and clinicopathologic findings in horses positive and negative for Clostridium difficile infection
Authors: Ruby Rebecca , Magdesian K. Gary , Kass Philip H.
Published: March 2009

Objective—To compare clinical, microbiologic, and clinicopathologic findings among horses infected with Clostridium difficile that had toxin A in their feces, horses with evidence of C difficile infection that were negative for toxin A in their feces, and horses with diarrhea that were negative for C difficile infection.

Design—Cross-sectional study.

Animals—292 horses and foals with diarrhea.

Procedures—Feces were submitted for microbial culture and tested for the C difficile antigen glutamate dehydrogenase and for toxin A with a commercial ELISA.

Results—Horses with toxin A in their feces had higher band neutrophil count, rectal temperature, hospitalization time prior to the onset of diarrhea, and total hospitalization time than did horses without evidence of C difficile infection, and 32 of the 33 (97%) horses with toxin A in their feces had received antimicrobials prior to the onset of diarrhea. Horses with toxin A in their feces had a significantly higher mortality rate than did horses negative for toxin A in their feces. Sensitivity and specificity of the ELISA for detection of C difficile antigen were 93% and 88%, when assay results were compared with results of microbial culture following direct plating, and 66% and 93%, when assay results were compared with results of microbial culture following broth enrichment.

Conclusions and Clinical Relevance—Results provided some evidence that horses positive for toxin A had more severe clinical disease than did horses with evidence of C difficile infection that were negative for toxin A and horses with diarrhea without evidence of C difficile infection.
Synthesis of Phenyl-1,3-thiazole Substituted Amino s-triazines as Antibacterial Agents
Authors: Gahtori Prashant , Singh BK , Das Aparoop
Published: March 2009

Amino s-triazines are widely believed to exert their antibacterial effects by nonspecific mechanisms. We assessed the extent to which physicochemical properties can be exploited to promote discriminative activity. In a wide search program towards new and efficient antibacterial agents, a series of amino substituted s-triazines were synthesized and subsequently screened for their in-vitro antibacterial activity against three Gram positive (Bacillus subtilis, B. cereus, Staphylococcus aureus) and three Gram-negative microorganism (Salmonella typhi, Escherichia coli, Klebsiella aerogenes) by the broth dilution technique, recommended by European Committee for antimicrobial susceptibility testing (EUCAST) with reference to streptomycin. The phenyl-1,3-thiazole substituted amino-s-triazine derivatives showed good antibacterial activity. Key words: Antibacterial activity, Bacterial resistance, Broth dilution technique, Physicochemical properties, s-Triazine. doi: 10.3329/dujps.v7i2.2164 Dhaka Univ. J. Pharm. Sci. 7(2): 107-111, 2008 (December)
Swelling and Erosion Modulation of Sterculia Foetida Gum Through Real Time Texture Probing
Authors: Namdeo Bendgude , Vidya Iyer , Sushilkumar Poddar
Published: March 2009

In the present investigation an attempt has been made to increase therapeutic efficacy, reduce frequency of administration and improve patient compliance by developing controlled release matrix tablets of diltiazem hydrochloride. Diltiazem hydrochloride was formulated as oral controlled release matrix tablets by using sterculia foetida gum. SFG fines were characterized with scanning electron microscopy. The purpose of this study was to optimize release profile of the highly water soluble drug from SFG matrix by using water soluble and swellable excipients like lactose and microcrystalline cellulose respectively. Tablets were prepared by direct compression, and their swelling behavior in presence of these excipients was assessed with the help of a Texture Analyzer. Dissolution assessment was performed using USP 26 apparatus 2 modified by insertion of a mesh to prevent sticking of the tablets to the bottom of vessel and allow them to swell three dimensionally. The interdependence of swelling front movement in relation to excipients type and progression of drug release are explained. It was concluded that unlike in conventional dosage forms insertion of excipients in hydrophilic controlled release tablets containing a water soluble drug gave the finger print information of drug release profile. In vitro drug release from these matrices was characterized and confirmed with the help of real time texture probing. Results indicated that it is possible to achieve desired modulation in the drug release profile by inclusion of lactose and microcrystalline cellulose. Key words: Diltiazem HCl, Sterculia Foetida Gum, Swelling and erosion, Lactose, Texture analysis. doi: 10.3329/dujps.v7i2.2167 Dhaka Univ. J. Pharm. Sci. 7(2): 127-132, 2008 (December)
Antimicrobial Activity Studies of Mixed Ligand Metal Complexes of Some Dibasic Acid and Heterocyclic Bases
Authors: Hossain Md Belayet , Hassan Md Nazmul , Yousuf MA , Salam MA
Published: March 2009

Mixed ligand transition metal complexes of Cu(II), Co(III), Rh(III) and Pt(IV) ions with dibasic acids viz., diphenic acid and adipic acid as primary ligands and amine bases as secondary ligands have been synthesized. They were characterized by conventional physical and chemical analyses. The antibacterial and antifungal activities have been evaluated for the synthetic ligands. Disc diffusion methods were employed for antimicrobial assays against five pathogenic bacteria and two fungi. The complexes containing 8-hydroxy quinoline as secondary ligand were much more active than the other complexes. In addition, the complex [Rh(DA)(8-HQ)(H2O)2] (4) showed the highest antibacterial activity against all bacteria tested (where, DA = Diphenic acid, 8-HQ = 8-hydroxyquinoline) and the complex [Pt(A)2(Q)2] (3) showed the lowest. On the other hand, he highest inhibition of growth occurred by complex K[Cu(DA)(8-HQ)] (1) against the fungi Botryodiplodia theobromae and the lowest by complex [Rh(DA)(8-HQ)(H2 O)2] (4) against the fungi Colletotrichum gloesparioides. Key words: Biological activity, Diphenic acid, Heterocyclic amine, Mixed ligand complexes doi: 10.3329/dujps.v7i2.2170 Dhaka Univ. J. Pharm. Sci. 7(2): 145-148, 2008 (December)
Adolescent Male Reproductive Health Knowledge and Practices in Bangladesh
Authors: Ahmed Faez , Kabir Abdul Kalam Lutful , Islam Md Shafiqul , Rouf Abu Shara Shamsur
Published: March 2009

Opinions on reproductive health education at the onset of puberty at present were studied by using a structured questionnaire consisting of 13 questions with a view to know their conception about it. A total of 800 male students were randomly selected of which 400 were from two public and the rest 400 from private universities situated in Dhaka, Bangladesh. At least half of the university students (384, 48%) did not understand much about puberty and remained confused. A large number of adolescents felt shy (208, 26%), scared (56, 7%), least bothered (112, 14%) and were not at all aware (40, 5%) of their onset of puberty. The respondents reported to have discussion their pubertal changes mainly with their male peers (672, 84%) and a very little access to parents (16, 2%) and elder brothers (16, 2%). A few respondents talked with their teachers (40, 5%). Their shared feelings were not informative and rather incorrect for maintaining good reproductive health at a growing time. On the contrary, they were rather warned by the persons not to disclose it to others. Most of the respondents (672, 84%) felt sex education is essential for better reproductive health management, a few of them (88, 11%) opposed this idea and some of them remained silent (40, 5%). Half of the respondents (760, 50%) preferred reproductive health education should be included in secondary and higher secondary levels (375, 25%), in the university level (166, 11%) and very few wanted it to be included in primary level (93, 6%). A few number of respondents (92, 6%) preferred non-formal reproductive health education. Some of the respondents (785, 23%) wanted to learn through curriculum and discussion with partners on sexual matter, reproductive organs and their functions (765, 16%), on STIs and AIDS (665, 17%) for safe sexual life. They (580, 11%) want to know the process of pregnancy and lactation, menstruation (356, 7%) and protection from unwanted sex (320, 6%) and other related issues (130, 2%). Most of the respondents (600, 75%) have no clear idea on the impact of addiction on sexual activity. However, a few number of respondents (128, 16%) believed that any drug addiction might cause decreased sexual activity while the other respondents (72, 9%) kept silent. Key words: Adolescent, Male, Reproductive Health, Sex education, Curriculum, Drug addiction, Secondary level. doi: 10.3329/dujps.v7i2.2171 Dhaka Univ. J. Pharm. Sci. 7(2): 149-154, 2008 (December)
Effects of Plastic and Acrylate Polymers on the Release Profile of Ambroxol Hydrochloride Controlled Release Pellets
Authors: Ahmed Ishtiaq , Roni Monzurul Amin , Kibria Golam , Islam Muhammad Rashedul , Rahman Md Habibur
Published: March 2009

The effects of Ammonio Methacrylate copolymer dispersion (EudragitÂ® NE 30 D) and Polyvinyl Acetate dispersion (KollicoatÂ® SR 30 D) are compared on the in vitro release of Ambroxol Hydrochloride from coated pellets in the current study. The nuclei pellets were manufactured by Extrusion-Spheronization with the drug, microcrystalline cellulose, lactose, maize starch, and hydroxypropyl methylcellulose followed by fluid bed coating. Dissolution study of coated pellets was performed with USP Type-II apparatus in acidic (0.1N HCl for 1 h) and buffer (phosphate buffer, pH 6.8 for 11 h) media to simulate gastrointestinal environment. The release profile of drug from two types of polymers were distinct and drug release was sustained longer by Polyvinyl Acetate film than Acrylate polymer. Key words: Aqueous coating, EudragitÂ® NE 30D, KollicoatÂ® SR 30D, release kinetics, pellets, extrusion-spheronization doi: 10.3329/dujps.v7i2.2176 Dhaka Univ. J. Pharm. Sci. 7(2): 181-186, 2008 (December)
The ̣Hurūfī Moses: An Example of Late Medieval ‘Heterodox’ Interpretation of the Qur'an and Bible
Authors: Mir-Kasimov Orkhan
Published: March 2009

The foundational work of Ḥurūfī doctrine, the Jāwdān-nāma (‘Eternal Book’) of Faḍlallāh Astarābādī (d. 796/1394), is often described as a Qur'an commentary. More specifically, a rich stock of Qur'anic ayas and images, often accompanied by references to the Biblical Old and New Testaments, constitutes the very language chosen by the author of the Jāwdān-nāma in order to express his teaching. This syncretistic approach is one of the most interesting particularities of the Jāwdān-nāma. This article sees to explore how the Jāwdān-nāma uses a number of symbols from the Moses story, such as the Tent of Meeting, Mount Sinai, the Broken Tablets of Law, the Rod of Moses, the Parting of the Waters and the Burning Bush, so as to demonstrate the ways in which the interpretation of the Moses story in the Jāwdān-nāma can be seen as an example of the assimilation of the Qur'anic text in the milieu of late medieval Iranian ‘heterodox’ movements.
The Angels inSūrat al-Malāʾika: Exegeses of Q. 35:1
Authors: Burge S.R.
Published: March 2009

The opening aya of Q. 35 (Sūrat al-Malāʾika or Sūrat al-Fāṭir) is one of only a few which describe the relationships between God, humans and angels: it attests to the creative power of God and describes the angels as winged messengers, the only aya in which angels are portrayed in this way. However, two of the most important words in this aya are often passed over without comment or consideration by modern translators and commentators alike: malak (malāʾika) and fāṭir, which are usually given the translations ‘angel’ or ‘messenger’ and ‘Creator’ respectively. The precise meanings of malak and fāṭir are not the only difficulties in this aya that appear to have posed problems. The three distributive adjectives found in the aya (mathnā, thulāth and rubāʿ) tend in modern translations to be given interpretations not found in the classical exegeses of the aya. This article will discuss the implications of the various different interpretations of these five terms, and explore whether they are best translated following the modern translators or the classical exegetes.
To What Extent Did Abu ʿAmr ibn al-ʿAlā and al-Kisāʾī Adhere to Their Respective Schools of Grammar? An Analytical Study in the Light of the Qur'anic qirāʾāt
Authors: Hanan Mustapha Nik
Published: March 2009

In this article the author aims to present evidence of the extent to which Abū ʿAmr and al-Kisāʾī conformed to the grammatical traditions of their respective Basran and Kufan schools in terms of the Qur'anic qirāʾāt. Within this context, the primary concern of this study revolves around the evident disagreements between them in their readings. The article identifies the specific differences which distinguish the reading of both figures, and discusses the stance of the leading Basrans or Kufans with regards to their acceptance or rejection of either of these two readings. Thus, this paper is an investigation of selected samples as a means of viewing the extent to which the qiraʾāt of these two authors correspond with their grammatical views.
Mathematical Programming Techniques for Sensor Networks
Authors: Sorokin Alexey , Boyko Nikita , Boginski Vladimir , Uryasev Stan , Pardalos Panos M.
Published: March 2009

This paper presents a survey describing recent developments in the area of mathematical programming techniques for various types of sensor network applications. We discuss mathematical programming formulations associated with these applications, as well as methods for solving the corresponding problems. We also address some of the challenges arising in this area, including both conceptual and computational aspects.
Notes on the Particulate Matter Standards in the European Union and the Netherlands
Authors: Priemus Hugo , Schutte-Postma Elizabeth
Published: March 2009

The distribution of Particulate Matter in the atmosphere, resulting from emissions produced by cars, trucks, ships, industrial estates and agricultural complexes, is a topical public health problem that has increased in recent decades due to environmental factors in advanced economies in particular. This contribution relates the health impact caused by concentrations of Particulate Matter (PM) in ambient air to the PM standards, the size of the particles and spatial planning. Diverging impacts of PM standards in legal regulation are discussed. The authors present a review of the development of legal PM standards in the European Union, with a specific reference to The Netherlands.
Indirect Potable Reuse: A Sustainable Water Supply Alternative
Authors: Rodriguez Clemencia , Van Buynder Paul , Lugg Richard , Blair Palenque , Devine Brian , Cook Angus , Weinstein Philip
Published: March 2009

The growing scarcity of potable water supplies is among the most important issues facing many cities, in particular those using single sources of water that are climate dependent. Consequently, urban centers are looking to alternative sources of water supply that can supplement variable rainfall and meet the demands of population growth. A diversified portfolio of water sources is required to ensure public health, as well as social, economical and environmental sustainability. One of the options considered is the augmentation of drinking water supplies with advanced treated recycled water. This paper aims to provide a state of the art review of water recycling for drinking purposes with emphasis on membrane treatment processes. An overview of significant indirect potable reuse projects is presented followed by a description of the epidemiological and toxicological studies evaluating any potential human health impacts. Finally, a summary of key operational measures to protect human health and the areas that require further research are discussed.
Physiological and Pathological Role of Alpha-synuclein in Parkinson’s Disease Through Iron Mediated Oxidative Stress; The Role of a Putative Iron-responsive Element
Authors: Olivares David , Huang Xudong , Branden Lars , Greig Nigel H. , Rogers Jack T.
Published: March 2009

Parkinson’s disease (PD) is the second most common progressive neurodegenerative disorder after Alzheimer's disease (AD) and represents a large health burden to society. Genetic and oxidative risk factors have been proposed as possible causes, but their relative contribution remains unclear. Dysfunction of alpha-synuclein (α-syn) has been associated with PD due to its increased presence, together with iron, in Lewy bodies. Brain oxidative damage caused by iron may be partly mediated by α-syn oligomerization during PD pathology. Also, α-syn gene dosage can cause familial PD and inhibition of its gene expression by blocking translation via a newly identified Iron Responsive Element-like RNA sequence in its 5’-untranslated region may provide a new PD drug target.
Dielectric Properties of Binary Solvent Mixtures of Dimethyl Sulfoxide with Water
Authors: Yang Li-Jun , Yang Xiao-Qing , Huang Ka-Ma , Jia Guo-Zhu , Shang Hui
Published: March 2009

In this paper, the dielectric properties of water-dimethylsulfoxide (DMSO) mixtures with different mole ratios have been investigated in the range of 1 GHz to 40 GHz at 298 K by using a molecular dynamics (MD) simulation. Only one dielectric loss peak was observed in the frequency range and the relaxation in these mixtures can be described by a single relaxation time of the Davidson-Cole. It was observed that within experimental error the dielectric relaxation can be described by the Debye-like model (β ≈ 1, S.M. Puranik, et al. J. Chem. Soc. Faraday Trans.1992, 88, 433 - 435). In general, the results are very consistent with the experimental measurements.
Polymer Hydrogel/Polybutadiene/Iron Oxide Nanoparticle Hybrid Actuators for the Characterization of NiTi Implants
Authors: Jeličić Aleksandra , Friedrich Alwin , Jeremić Katarina , Siekmeyer Gerd , Taubert Andreas
Published: March 2009

One of the main issues with the use of nickel titanium alloy (NiTi) implants in cardiovascular implants (stents) is that these devices must be of very high quality in order to avoid subsequent operations due to failing stents. For small stents with diameters below ca. 2 mm, however, stent characterization is not straightforward. One of the main problems is that there are virtually no methods to characterize the interior of the NiTi tubes used for fabrication of these tiny stents. The current paper reports on a robust hybrid actuator for the characterization of NiTi tubes prior to stent fabrication. The method is based on a polymer/hydrogel/magnetic nanoparticle hybrid material and allows for the determination of the inner diameter at virtually all places in the raw NiTi tubes. Knowledge of the inner structure of the raw NiTi tubes is crucial to avoid regions that are not hollow or regions that are likely to fail due to defects inside the raw tube. The actuator enables close contact of a magnetic polymer film with the inner NiTi tube surface. The magnetic signal can be detected from outside and be used for a direct mapping of the tube interior. As a result, it is possible to detect critical regions prior to expensive and slow stent fabrication processes.
Sensory Properties and Color Measurements of Dietary Chocolates with Different Compositions During Storage for Up to 360 Days
Authors: Popov-Raljić Jovanka V. , Laličić-Petronijević Jovanka G.
Published: March 2009

In this work sensory characteristics (appearance – color, brilliance, shape and surface; texture – structure, break, firmness and chewiness; aroma – odor and taste) of dietary chocolates of different compositions were evaluated, in parallel with color parameter measurements. Color was determined instrumentally on the top and bottom surfaces, using a "MINOLTA" Chroma meter CR 400 thristimulus colorimeter. Sensory evaluation was performed by a group of experienced panelists immediately after the production (0 – 30 days), and then after 90, 180, 270 and 360 days of storage under ambient conditions (t = 18 – 20°C). Results were statistically analyzed by the two-factorial analysis of variance (MANOVA) and with the LSD – test. It was concluded that the storage time up to one year had statistically highly significant (p < 0.01) effects on the sensory attributes of chocolate, as well as on instrumentally measured color parameters.
Responding to Stakeholder Research needs using a visitor Monitoring Survey: The case of the Great Barrier Reef Tourism Industry
Authors: Coghlan Alexandra , Prideaux Bruce
Published: March 2009

Marketed internationally as an iconic tourism experience, Australia's Great Barrier Reef (GBR) faces a range of issues similar to those faced by coral reefs in other parts of the world. According to the Great Barrier Reef Marine Park Authority (GRBMPA), the management body responsible
for the reef, 1.9 million tourists visit the reef annually, using marine tour operators that offer a wide range of tour products. Management of the tourism industry is based on a zoning system that requires natural and social science input. Data on visitor experiences and satisfaction have
been collected in the past by CRC Reef Research, and more recently by a new long-term reporting system of reef tourist visitation supported by the Marine and Tropical Sciences Research Facility (MTSRF) funded by the Australian Federal Government. The sustainability of this industry is influenced
by a range of natural (climate change, crown-of'thorns, etc.) and social (rising cost of fuel, changing travel patters, emerging markets) issues. These issues are reviewed followed by analysis of the reef tourism experience within this natural and social context. Data used in this analysis
were drawn from a visitor monitoring survey that is discussed in this article. The monitoring program was designed to collect data that can be compared on a monthly and annual basis to enable comparison over time with the aim of identifying emerging social and environmental issues and threats
to determine their effect on the sustainability of reef tourism. Finally, the article identifies a number of solutions and strategies that may be available to tourism operators.
Dolphin Watch Tourism: Two Differing Examples of Sustainable Practices and Proenvironmental Outcomes
Authors: Mayes Gayle , Richins Harold
Published: March 2009

This study compares the management practices and content of the education/interpretation commentaries of two differing commercial dolphin watch operators in Nelson Bay, New South Wales, which is promoted as the "Dolphin Capital of Australia." The major objective of the study was to
measure and evaluate the postexperience effectiveness of the education/interpretation components on the self-reported proenvironmental attitudes, beliefs, intended behaviors, and intended actions of participants. A questionnaire was administered to participants immediately after their half-day
dolphin watch cruises. The most important feature of the experience for all participants was the opportunity to see wild dolphins behaving naturally in their natural habitat. Although the management practices and content of the education and interpretation messages differed aboard the two
vessels, no significant differences occurred between the two differing samples for impacts on visitors' intended proenvironmental actions. Significant differences did occur between samples for the self-reported impacts on participants' strength of support for conservation of marine wildlife
and for conservation of dolphins. The effectiveness and influence of the dolphin watch cruises on proenvironmental attitudes, beliefs, intended behaviors, and actions of participants appears to be related to two factors: the quality and content of the education/interpretive message, and the
intensity level of the dolphin watching experience.
Quantifying Community Perceptions of Marine Environments for Marine Protected Area Planning: When is the Reef too Crowded?
Authors: Breen Barbara Bollard , Breen Daniel
Published: March 2009

A widely accepted overall goal in marine protected area management is to allow for multiple uses that are appropriate and sustainable. An issue relevant to this goal is the quality of the experience perceived by users of marine protected areas. Understanding relationships between stakeholder
values at different sites and their perceptions of crowding and other impacts is, therefore, important information for managers. As a consequence, the study reported here compares the perceptions of individuals involved in tourism, commercial and recreational fishing, scientific research,
boating, yachting, and other activities with values derived from the Great Barrier Reef Marine Park management and scientific databases. Surveys of regular reef users indicated that different activities were targeted at specific areas according to a combination of values that could be statistically
analyzed and mapped across the region. Respondents considered that current levels of use were too high for many locations in the Cairns Sector. They preferred to see fewer people and vessels, but were more concerned by the number of vessels than the number of people. Acceptable levels of use
varied widely depending on the location. At established tourism destinations and major recreational fishing sites, responses indicated that a large number of vessels (20–100) and people (100–1,000) could be tolerated. At areas visited only rarely, only low levels of use were acceptable.
This suggests that there may be shifts in perceptions at sites that become used more frequently. The results have implications for management as reef use continues to increase and extend to other locations. Results from the survey were used to assess management settings to limit the level
and type of activity in different areas. The techniques used have since been valuable in helping to plan for sustainable marine use in other regions in Australia and might be usefully employed elsewhere.
Interview with Doris C. Rusch
Authors: Fernández-Vara Clara
Published: March 2009

An interview with Doris C. Rusch, postdoctoral researcher at the Singapore-MIT GAMBIT Game Lab, conducted by Clara Fernández-Vara.
Subsea Pressure Boost/Separation: A Necessity for Deepwater Development?
Authors: Beran W.T. , Hatton G.J. , Stires J.L. , Gunderson R.H.
Published: March 2009

Early in the DeepStar program, both subsea pressure boosting and subseaseparation were identified as potentially necessary components for implementingdeepwater subsea production. The initial goal for the entire DeepStar programwas to have the technical capability to implement a deepwater Gulf of Mexico(GOM) subsea production system by 1996. Thus, the current status of subsea pumpand separator development was reviewed to determine whether such equipmentwould meet DeepStar technical requirements, and could be implemented by the1996 target date. Assessments were made of the system arrangements and costsfor implementing subsea pumps or separators relative to alternativeapproaches.

This paper addresses a number of technical aspects and cost implications ofthese pumps and separators. It notes the field development circumstances thatfavor implementation of subsea pumping and subsea separation, but also suggestspotential system design alternatives to these components.

Introduction

Oil production from deepwater reservoirs in the Gulf of Mexico may requirein-field pressure boosting in order to achieve satisfactory flow rates over thelife of the field. Satellite subsea production systems, such as proposed forDeepStar, are prime candidates for pressure boosting, particularly as theoffset distances lengthen and production pipeline friction losses increase.

Subsea multiphase pumps, as well as subsea production separators withliquid-phase pumps and gas compressors, are being developed for satellite fieldpressure boosting applications. The multiphase pump systems are generallysimpler systems than the subsea separators, but face technical problemsinherent in pumping gas-entrained liquids of varying gas content (up to 100%gas in some applications). Subsea separation overcomes these multiphase pumpingproblems and significantly reduces pumping power consumption; it can alsopotentially relieve hydrate problems by separating produced gas from producedwater. However, subsea separators are generally more complex and costly thanmultiphase pumps, and have to demonstrate reliable, low maintenance separationfor site-specific well fluids.
Comparison Between Measured and Simulated Dynamic Responses of a Power Cable
Authors: Kaasen K.E. , Nordsve N.T.
Published: March 2009

A power cable has been instrumented with inclinometers and acoustictransponders for measurement of angular and linear motion. The cable hangs in aU-shape between the fixed and the floating platforms at Veslefrikk. Most of thecable is below the sea surface.

Statistical parameters like standard deviations and power spectra ofmeasured motion responses are compared with similar statistics for responseswhich are simulated with a finite element computer program. The objective wasto verify the models in the simulation program. For some of the responses theagreement between measurements and simulations is very good. Others agree lesswell. Some of the differences can be explained by errors in the measurements, while others could be reduced by improving the simulation model at certainpoints. In particular, replacing the linear model for wave kinematics by anonlinear model and including a diffraction model to account for the movingplatform's influence on the wave field is recommended.

Introduction

In the Veslefrikk field there are two platforms. These are a jacket wellheadplatform and a semisubmersible which carries the processing plant, power plantand living quarters. Oil, gas, drilling fluid and electrical power aretransported through a number of lines (flexible pipes and cables) hanging inalmost parallel U-shapes between the platforms (Fig. 1). The length of eachline is approximately 150 m, and the horizontal distance between the end pointsis about 36 m. The horizontal separation between neighbouring lines is twometres. The larger part of the U is below the sea surface.

Each line is set in motion by two sources: The motion of the end which isfixed to the floating platform and the direct action of moving water'particles' along its submerged part. The motion of a line will set up internaldynamic forces and moments.

Curvature is of special concern, as well as possible bumping of lines intothe platforms or into each other. For the latter reason the units are designedto have as identical dynamic behaviour as possible.
Fiber Optic Telemetry for Deep Sea Robotics
Authors: Grobe Klaus , Amann Hans , Conogan R. , Simeoni P.
Published: March 2009

Teleguided Work in the deep sea requires broad band data transfer in twodirections without crosstalk or other electromagnetic interferences. Furthermore power supply to the seafloor is necessary in the range of tens ofkilowatts. A multipurpose umbilical of 8 – 10 km length represents abottleneck, especially as inertial masses of ROVs and various forces andmoments accompanying deep sea work have to be compensated.

Fiber optic telemetry allows for broad band data and video transfer free ofinterference and over long distances. These systems require a small crosssection in the umbilical, thus giving space for high voltage power supply andstrength members in a cable with an overall diameter in the range of 20 mm. Theperformance of deep sea robotics is increased as high definition multichannelcolour video and sonar transmission becomes possible, telemetry data bandwidthis increased and power supply through the cable can be provided.

The scope, structure and test results of fiber optic telemetry systems fordeep sea robotics are presented.

Introduction: Deep sea robotics

Exploration, control and use of the deep sea increase constantly. The deepsea, with water depth beyond 1000 m, covers 60% of the earth's surface, whereasthe deep sea plains and troughs with an average water depth of 4000 – 5000 mcover almost half of the globe. We learn to understand that global change isalso influenced by deep sea processes, be they geologic, biologic oroceanographic, at least if we concentrate on medium (10 – 103 years)and long term (103 - 106 years) processes. The deep seaoffers in addition a number of eventually attractive uses such as mining ofpolymetallic nodules or clathrates, to give just examples. Or the disposal ofwastes in geologically calm deepsea soils where more long term stable barriersexist than on land. It goes without saying that such uses must be effected inan environmentally acceptable manner. This, in turn, requires extended andcomplicated research and control of the many interdependent aspects of the deepsea.
Comparison of Fatigue Resistance of Various Longitudinal Weld Joints
Authors: Dexter R.J. , Kaufman E.J. , Fisher J.W. , Stout R.D. , Beach J.E.
Published: March 2009

Various types of one-sided and two-sided longitudinal weld joints were madein the web/flange connection of large-scale HSLA-80 I-section beams. Fatigueexperiments were conducted on 78 beams. As expected, there is a decrease in thefatigue strength of the one-sided welds relative to the standard double filletweld. Among the one-sided welds, the differences in the fatigue strength wereslight. The findings show that existing design rules for longitudinal filletwelds in bridges can be used for ships. The data provide a rational basis forthe selection of longitudinal weld joints, fit-up tolerances, and NDErequirements.

Introduction

The Navy is considering advanced (unidirectional) double-hull surfacecombatant ships. A simplified schematic of the advanced double-hull crosssection is contrasted with a conventional stiffened-panel hull cross section inFigure 1. The multiple load paths (redundancy) and improved stiffness inherentin a double-hull design offer potentially improved strength relative toconventional stiffened-panel hull construction [1]. The double-hull design mayhelp contain damage from leaking due to fatigue cracks. A cracking element ofthe double-hull framing system transfers load to adjacent members more easilythan stiffened-panel construction, reducing the probability of catastrophicfailure. These ships are also likely to be fabricated from modern high-strengthlow-alloy (HSLA) steels which offer increased strength and toughness relativeto conventional ship steels.

The unidirectional double hull concept has also been proposed for commercialtankers [2,3]. Concern for the environment has led the Oil Pollution Act of1990, which requires that new oil tankers over 5000 tons built for use in U.S.waters have double hulls [4]. The International Maritime Organization hasrequested that member countries also require these tankers to have double hulls[5]. In commercial tankers and bulk carriers fabricated from high-strengthsteel, fatigue cracking has become a serious problem. For example, betweenJanuary 1990 and September 1991, 36 bulk carriers suffered severe structuralcasualties due to corrosion and fatigue causing the loss of 21 ships and 250lives [6].
Zinc Project: Overview of the Subsea Control System
Authors: Stair M.A. , Clark G.R. , White John
Published: March 2009

This paper provides an overview of the Zinc Electrohydraulic MultiplexControl System, which provides for monitoring and control of 10 subsea wellsand the subsea manifold functions as well as control and safety monitoringhardware for all Zinc process equipment located on the Alabaster platform. Adescription of the system architecture including support and test equipment anda discussion of the design requirements is provided, with an emphasis on thesubsea template based hardware. A companion paper describes Exxon's maintenanceand remedial action philosophy which resulted in this equipmentconfiguration.

Introduction

Zinc is a subsea production system installed in 1,460 ft of water fordevelopment of the Mississippi Canyon 354 Field in the Gulf of Mexico. Thesubsea template is linked to Exxon's Alabaster platform, located in MississippiCanyon Block 397 approximately 6 miles west of Zinc's location, via separateelectrical and hydraulic control umbilicals.

The Zinc Subsea Production Control System is characterized by a number ofsignificant design features:All subsea control system components located on a self-contained controlskid which is integrated into the production manifold.Control and safety monitoring of all platform-based Zinc process equipmentintegrated with the subsea production control system.Guidewire installed subsea system components using a vessel ofopportunity.Subsea intervention/maintenance by a work class 'ROV of opportunity'.

The control system architecture is implemented as an Electro-HydraulicMultiplexed system with dual electric and hydraulic supplies consolidated intoSubsea Control Pods (SCPs) for Xmas trees and manifold functions. Eachinterchangeable SCP, however, provides control and monitoring functions foreither two trees, or one tree plus the Zinc subsea production manifold. Allsubsea hydraulic and chemical supplies are routed from the umbilical endterminations to the tree and manifold functions via fully welded hard pipedtubing assemblies with metal-to-metal, self-sealing couplings being used at alldisconnection points. Electrical connections between the incoming umbilical anddistribution network to individual Control Pods are via ROVmanipulator-deployed inductive connector assemblies. The entire templateelectrical distribution network with its supporting framework is recoverableusing a simple Running Tool.
Total Quality Management Applications on the Zinc Subsea Production System
Authors: Bednar J.M. , Loes George
Published: March 2009

The concepts of early quality planning, and team approach, are key elementsof the Total Quality Management (TQM) program that was applied by ExxonCompany, U.S.A. during the execution of the Zinc Subsea Production SystemProject. This paper describes how these elements were applied during initialdesign and specification development, vendor and/or contractor selection, procurement, detail engineering, documentation and configuration control, manufacturing and fabrication, testing and system integration, and finallysystem installation.

Introduction

Deep water projects necessitate the application of recent advances intechnology and equipment, as well as the utilization of diversified humanresources, both from within the producing company's own organization, as wellas from the multitude of contractor and consulting organizations that alsocontribute to the project. In today's environment, where reduced budgets, enhanced safety, and aggressive schedules are becoming customary, a higheremphasis on procedural and equipment quality and reliability is imperative toensure that the end product will meet the performance standards that arerequired and expected. This emphasis on quality must begin during the earlystages of the project, where quality planning must be stressed over reliance oninspection to find latent defects.

The Zinc Subsea Production System was managed by a Project Team from ExxonU.S.A.'s Offshore Division (now Southeastern Division) based in New Orleans, Louisiana. Under the direction of the Project Leader, the core Team consistedof engineers from the Division's Production Technology group. Other groupswithin the Division, such as Geology, Reservoir Engineering, Operations, Drilling, and Contracts, and other Company groups outside the Division, such asExxon Production Research Co. and Headquarters Purchasing, assisted with expertadvice and services, as required. Consultants were added to the Team to providespecialty services in the areas of cost and schedule control, system interfacecontrol, and ROV (remote operated vehicle) interfacing, as well as to helpdefine and implement the project Quality Assurance program.

The various Zinc contractors included engineering firms, material suppliers, equipment manufacturers, fabricators, hydraulic system and testing specialists, ROV operators, and installation companies. The work was performed in severallocations primarily in the U.S., but also in England, France, and Japan.
Efficient Cross‐Coupling Reactions of Nitrogen Nucleophiles with Aryl Halides in Water
Authors: Teo Yong‐Chua
Published: March 2009

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A facile and practical strategy has been developed for the N‐arylation of nitrogen nucleophiles with aryl halides catalyzed by a combination of iron(III) chloride [FeCl3] and dimethylethylenediamine (dmeda) in water. A variety of nitrogen nucleophiles including pyrazole, indole, 7‐azaindole and benzamide afforded the N‐arylated products in the presence of the catalytic system (in up to 88% yield).
Total Synthesis of Ciguatoxin
Authors: Hamajima Akinari , Isobe Minoru
Published: March 2009

Eines der Haupttoxine bei Fischvergiftungen, das Ciguatoxin (siehe Struktur), war Ziel einer Totalsynthese. Der Syntheseweg beruht auf der Kupplung dreier Segmente, und die Schlüsselumwandlungen umfassen eine Komplexbildung zwischen Acetylen und Dicobalthexacarbonyl.

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Gas‐Phase Synthesis and Reactivity of the Lithium Acetate Enolate Anion, −CH2CO2Li
Authors: Meyer Matthew M. , Khairallah George N. , Kass Steven R. , O'Hair Richard A. J.
Published: March 2009

Aerial pingpong: The lithium acetate enolate anion, the prototypical lithium salt of an α‐deprotonated carboxylate, was prepared in the gas phase by electrospray ionization (ESI) and collision‐induced ionization (CID). Its structure, reactivity, and energetics are presented along with the results of high‐level computations.

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Iron‐Catalyzed Chemoselective ortho Arylation of Aryl Imines by Directed CH Bond Activation
Authors: Yoshikai Naohiko , Matsumoto Arimasa , Norinder Jakob , Nakamura Eiichi
Published: March 2009

No Fe‐ar: Iron catalyzes an imine‐directed CH bond activation to introduce an ortho‐aryl group to an acetophenone‐derived imine using a diarylzinc reagent (see scheme), whereas palladium catalyzes the conventional substitution reaction . The title reaction features mild and selective CH bond activation in the presence of aryl bromide, chloride, or sulfonate groups, and 1,2‐dichloroisobutane is essential to achieve such selectivity.

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Facile Synthesis of Ultrathin and Single‐Crystalline Au Nanowires
Authors: Wang Chao , Sun Shouheng
Published: March 2009

Thin is in! Recent advance in solution‐phase synthesis has led to the formation of ultrathin single‐crystalline Au nanowires with diameters of less than 10 nm. This Focus Review summarizes these syntheses and provides an exciting example of the electron transport in the ultrathin Au nanowires to demonstrate their great potential for nanoelectronic applications.

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Au nanowires have attracted significant interest in nanomaterials research owing to their chemical stability and high conductivity for potential nanoelectronic applications. However, previous syntheses yielded only polycrystalline Au nanowires with diameters larger than 10 nm. Very recent advances in solution‐phase synthesis have led to the formation of ultrathin single‐crystalline Au nanowires with diameters of less than 10 nm. This Focus Review summarizes the synthesis, characterization, and transport studies of these ultrathin single‐crystalline Au nanowires for potential electronic device applications.
Sodium benzoate exposure downregulates the expression of tyrosine hydroxylase and dopamine transporter in dopaminergic neuronsin developing zebrafish
Authors: Chen Qian , Huang Nan‐nan , Huang Jin‐tao , Chen Shen , Fan Jinjin , Li Chaohong , Xie Fu‐kang
Published: March 2009

BACKGROUND: Recent data have demonstrated that treatment with sodium benzoate (SB) leads to significant developmental defects in motor neuron axons and neuromuscular junctions in zebrafish larvae, thereby implying that SB can be neurotoxic. This study examined whether SB affects the development of dopaminergic neurons in the zebrafish brain. METHODS: Zebrafish embryos were exposed to different concentrations of SB for various durations, during which the survival rates were recorded, the expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the neurons in the ventral diencephalon were detected by in situ hybridization and immunofluorescence, and the locomotor activity of larval zebrafish was measured. RESULTS: The survival rates were significantly decreased with the increase of duration and dose of SB‐treatment. Compared to untreated clutch mates (untreated controls), treatment with SB significantly downregulated expression of TH and DAT in neurons in the ventral diencephalon of 3‐day post‐fertilization (dpf) zebrafish embryos in a dose‐dependent manner. Furthermore, there was a marked decrease in locomotor activity in zebrafish larvae at 6dpf in response to SB treatment. CONCLUSIONS: The results suggest that SB exposure can cause significantly decreased survival rates of zebrafish embryos in a time‐ and dose‐dependent manner and downregulated expression of TH and DAT in dopaminergic neurons in the zebrafish ventral diencephalon, which results in decreased locomotor activity of zebrafish larvae. This study may provide some important information for further elucidating the mechanism underlying SB‐induced developmental neurotoxicity. Birth Defects Res (Part B)86: 85‐91, 2009. © 2009 Wiley‐Liss, Inc.
A novel inhibitory kinetic fluorimetric method for the determination of trace methomyl in environmental samples
Authors: Fan Jing , Shao Xiaojing , Xu Haizhu , Feng Suling
Published: March 2009

A novel inhibitory kinetic fluorimetric method for the determination of trace methomyl was proposed. It was shown that the Fenton reagent oxidized rhodamine B in acid medium which enabled the fluorescence quenching of the latter. The presence of trace methomyl clearly inhibited the reaction. Upon addition of EDTA, a good linear relationship between the inhibitory effect and the concentration of methomyl was observed, together with improved stabilization and sensitivity. Factors affecting the determination of trace methomyl were investigated systematically. Under the optimum conditions, the linear range for the determination of methomyl was 0.04–2.2 µg/mL; the detection limit and the quantification limit for methomyl were 0.011 and 0.037 µg/mL, respectively. The proposed method was applied to the determination of methomyl in four environmental soil samples, six environmental water samples and one synthetic sample; the results were compared with those determined by the HPLC method. The recoveries and the relative errors were 83.5–101.2 and 0.47–2.02%, respectively. The possible reaction mechanism has also been discussed. Copyright © 2009 John Wiley & Sons, Ltd.
A Mechanism for Stochastic Decision Making by Bacteria
Authors: Hensel Zach , Xiao Jie
Published: March 2009

What mechanism underlies the induction of the lac operon? Expression from the lac operon is an all‐or‐none phenomenon. Recent work by Choi et al. combines single‐molecule imaging of gene expression with single‐cell induction measurements to develop a stochastic model describing the critical role of single lac‐repressor molecules in induction.

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