bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved arthritic knee health in a pilot RCT of phytotherapy
Authors: Hamblin Louise , Laird Alex , Parkes Edward , Walker Ann F.
Published: August 2008

Although practitioner-prescribed `western' herbal medicine (phytotherapy) is a popular complementary therapy in the UK, no clinical studies have been reported on patient-orientated outcomes. The objective of this pilot study was to investigate the effects of phytotherapy on symptoms of osteoarthritis of the knee. A previous study of Chinese herbal medicine for the treatment of irritable bowel syndrome, published in the Journal of the American Medical Association,1 acted as a model in the development of the protocol of this investigation.

Twenty adults, previously diagnosed with osteoarthritis of the knee, were recruited from two Inner London GP practices into this randomized, double-blind, placebo-controlled, pilot study carried out in a primary-care setting. All subjects were seen in consultation three times by a herbal practitioner who was blinded to the randomization coding. Each subject was prescribed treatment and given lifestyle advice according to usual practice: continuation of conventional medication where applicable, healthy-eating advice and nutrient supplementation. Individualized herbal medicine was prescribed for each patient, but only dispensed for those randomized to active treatment — the remainder were supplied with a placebo. At baseline and outcome (after ten weeks of treatment), subjects completed a food frequency questionnaire and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) knee health and Measure Yourself Outcome Profile (MYMOP) wellbeing questionnaires. Subjects completing the study per protocol (n = 14) reported an increased intake of wholegrain foods ( p = 0.045) and oily fish ( p = 0.039) compared to baseline, but no increase in fruit and vegetables and dairy products intakes.

There was no difference in the primary outcome measure of knee health assessed as the difference in the mean response (baseline-week 10) in WOMAC score between the two treatment groups. However, there was, compared with baseline, improvement in the active group ( n = 9) for the mean WOMAC stiffness sub-score at week 5 ( p = 0.035) and week 10 ( p = 0.060) but not in the placebo group ( n = 5). Furthermore, for the active, but not the placebo group, the mean WOMAC total and sub-scores all showed clinically significant improvement (≥ 20%) in knee symptoms at weeks 5 and 10 compared with baseline. Moreover, the mean MYMOP symptom 2 sub-score, mostly relating to osteoarthritis (OA), showed significant improvement at week 5 ( p = 0.02) and week 10 ( p = 0.008) compared with baseline for the active, but not for the placebo group.

This pilot study showed that herbal medicine prescribed for the individual by a herbal practitioner resulted in improvement of symptoms of OA of the knee.
A qualitative study of the experiences of mothers involved in street-based prostitution and problematic substance use
Authors: McClelland Gabrielle Tracy , Newell Robert
Published: August 2008

Abstract

This study aimed to enable a cohort of women to describe their personal experiences of motherhood in the context of problematic substance use and street-based prostitution. The study also aimed to describe the impact upon women of separation from their children. Findings that emerged from focus group data were organised into four over-arching themes: children and motherhood, personal accounts of drug use and street-based prostitution, risks to women and their children and supportive/unsupportive factors in the women’s lives. Each theme consisted of many categories that illustrated the impact of dependent drug use and involvement in prostitution on the lives of the women and their children. This article describes the theme of children and motherhood. Involvement in street-based prostitution is extremely risky, frequently characterised by calculated risk taking, with consequences for both the woman and her children. Parental responsibilities and lifestyle contribute to stress, which is typically compounded by problematic substance use. Risks are increased for both the woman and her children when timely and appropriate support is unavailable. Emphasis should be placed upon the proactive identification and implementation of positive supportive strategies. Ethical approval was obtained via the Local Research Ethics Committee to undertake this research study.
Conserved upstream open reading frames in higher plants
Authors: Tran Michael K , Schultz Carolyn J , Baumann Ute
Published: August 2008

Background

Upstream open reading frames (uORFs) can down-regulate the translation of the main open reading frame (mORF) through two broad mechanisms: ribosomal stalling and reducing reinitiation efficiency. In distantly related plants, such as rice and Arabidopsis, it has been found that conserved uORFs are rare in these transcriptomes with approximately 100 loci. It is unclear how prevalent conserved uORFs are in closely related plants.

Results

We used a homology-based approach to identify conserved uORFs in five cereals (monocots) that could potentially regulate translation. Our approach used a modified reciprocal best hit method to identify putative orthologous sequences that were then analysed by a comparative R-nomics program called uORFSCAN to find conserved uORFs.

Conclusion

This research identified new genes that may be controlled at the level of translation by conserved uORFs. We report that conserved uORFs are rare (<150 loci contain them) in cereal transcriptomes, are generally short (less than 100 nt), highly conserved (50% median amino acid sequence similarity), position independent in their 5'-UTRs, and their start codon context and the usage of rare codons for translation does not appear to be important.
Fungal cytochrome P450 database
Authors: Park Jongsun , Lee Seungmin , Choi Jaeyoung , Ahn Kyohun , Park Bongsoo , Park Jaejin , Kang Seogchan , Lee Yong-Hwan
Published: August 2008

Background

Cytochrome P450 enzymes play critical roles in fungal biology and ecology. To support studies on the roles and evolution of cytochrome P450 enzymes in fungi based on rapidly accumulating genome sequences from diverse fungal species, an efficient bioinformatics platform specialized for this super family of proteins is highly desirable.

Results

The Fungal Cytochrome P450 Database (FCPD) archives genes encoding P450s in the genomes of 66 fungal and 4 oomycete species (4,538 in total) and supports analyses of their sequences, chromosomal distribution pattern, and evolutionary histories and relationships. The archived P450s were classified into 16 classes based on InterPro terms and clustered into 141 groups using tribe-MCL. The proportion of P450s in the total proteome and class distribution in individual species exhibited certain taxon-specific characteristics.

Conclusion

The FCPD will facilitate systematic identification and multifaceted analyses of P450s at multiple taxon levels via the web. All data and functions are available at the web site http://p450.riceblast.snu.ac.kr/.
Grazing phenomena and fragmented strange attractors in a harmonically forced, piecewise, linear system with impacts
Authors: Luo A C J , Chen L
Published: August 2008

In this article, the grazing bifurcations and flows of an idealized gear transmission system with impact are investigated from the non-smooth dynamical system theory of Luo [1–3]. The necessary and sufficient conditions for such grazing bifurcations of all the generic mappings are obtained. The initial and final grazing, switching manifolds for all the generic mappings are introduced for the grazing motions. The fragmentation of strange attractors in non-smooth dynamical systems is described mathematically. The fragmentation mechanism of the strange attractors for such a non-smooth dynamical system is discussed qualitatively. Such a fragmentation of strange attractors is illustrated numerically through the switching sets. This investigation will provide a better understanding of the mathematical structures and characteristics of strange attractors in non-smooth dynamical systems. This is very useful to determine the origin of the vibration and noise in the gear transmission systems.
Letter: Correlation between Phosphorylation Ratios by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometric Analysis and Enzyme Kinetics
Authors: Kang Jeong-Hun , Kuramoto Masanori , Tsuchiya Akira , Toita Riki , Asai Daisuke , Sato Yuko T. , Mori Takeshi , Niidome Takuro , Katayama Yoshiki
Published: August 2008

To identify the correlation between the phosphorylation ratios by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-ToF MS) analysis and enzyme kinetics ( Km, Vmax and Vmax / Km) it is important to understand whether MALDI-ToF MS can be applied for monitoring the properties of peptides that are substrates of protein kinases. The correlation between phosphorylation ratios and enzyme kinetics was examined using peptides for protein kinase C (PKC) and for 60 kDa phosphoprotein, encoded by the cellular sarcoma gene (c-Src). Phosphorylation ratios, analyzed by MALDI-ToF MS, showed a higher correlation coefficient ( r = > + 0.7) for Vmax / Km compared with that ( r = < ± 0.6) for Km or Vmax. For ion modes, a higher correlation coefficient between phosphorylation ratios and Vmax / Km was identified in the positive mode ( r = > + 0.7) compared with that in the negative mode ( r = < + 0.5). These results suggest that MALDI-ToF MS is a useful tool to evaluate Vmax / Km of peptides for protein kinases.
Identification of the Tyrosine Nitration Sites in Human Endothelial Nitric Oxide Synthase by Liquid Chromatography-Mass Spectrometry
Authors: Zickus Michael A. , Fonseca Fabio Vasconcelos , Tummala Monorama , Black Stephen M. , Ryzhov Victor
Published: August 2008

The formation of nitric oxide (NO) in biological systems has led to the discovery of a number of post-translational protein modifications that can affect biological conditions such as vasodilation. Studies both from our laboratory and others have shown that beside its effect on cGMP generation from soluble guanylate cylcase, NO can produce protein modifications through both S-nitrosylation of cysteine residues. Previously, we have identified the potential S-nitrosylation sites on endothelial NO synthase (eNOS). Thus, the goal of this study was to further increase our understanding of reactive nitrogen protein modifications of eNOS by identifing tyrosine residues within eNOS that are susceptible to nitration in vitro. To accomplish this, nitration was carried out using tetranitromethane followed by tryptic digest of the protein. The resulting tryptic peptides were analyzed by liquid chromatography/mass spectrometry (LC/MS) and the position of nitrated tyrosines in eNOS were identified. The eNOS sequence contains 30 tyrosine residues and our data indicate that multiple tyrosine residues are capable of being nitrated. We could identify 25 of the 30 residues in our tryptic digests and 19 of these were susceptible to nitration. Interstingly, our data identified four tyrosine residues that can be modified by nitration that are located in the region of eNOS responsible for the binding to heat shock protein 90 (Hsp90), which is responsible for ensuring efficient coupling of eNOS.
Proteome Profiling of Human Cerebrospinal Fluid: Exploring the Potential of Capillary Electrophoresis with Surface Modified Capillaries for Analysis of Complex Biological Samples
Authors: Zuberovic Aida , Hanrieder Jörg , Hellman Ulf , Bergquist Jonas , Wetterhall Magnus
Published: August 2008

A bottom-up proteomic approach, based on capillary electrophoresis (CE), in combination with matrix-assisted laser desorption/ionization tandem time-of-flight (MALDI-ToF/ToF) mass spectrometry, was used to analyze immunoaffinity depleted human cerebrospinal fluid (CSF) and compare it with a non-depleted sample. After enzymatic digestion and desalting, the tryptic peptides were separated by CE using PolyE-323 modified capillaries and fractionated off-line onto MALDI target plates for further analysis by MALDI and tandem mass spectrometry (MS/MS). The protein profile of the depleted sample was compared with non-depleted CSF. Overall, 84 proteins were identified with 95% significance in both samples. The significance scores for the proposed biomarkers, such as amyloid-like protein 1 precursor, could be increased up to 12 times after the depletion. Other proteins, often suggested to be related to neurodegenerative diseases, such as amyloid beta A4 protein precursor, superoxide dismutase and apolipoprotein E precursor could only be found in the depleted CSF samples. The effect of a derivatization of tryptic peptides with 2-methoxy-4,5-dihydro-1 H-imidazole reagent for protein identification by mass spectrometry was also employed to increase the number of identified proteins and the sequence coverages. The results presented in this study illustrate the benefit of combining a sample pre-fractionation step and a label's ability to enhance the ionization efficiency with the potential of CE using PolyE-323 modified capillaries in the analysis of complex samples. The straight-forward approach that provides speed and simplicity resulting in high-resolution separations and low sample consumption represents an easily applicable separation technique that can serve as a complement to other currently existing analytical approaches needed in modern proteomic analysis of clinically relevant samples.
The Preliminary Research of Identifying Motor and Sensory Fascicles Using near Infrared Diffuse Reflectance Spectroscopy in Combination with Soft Independent Modelling of Class Analogy
Authors: Bu ShouShan , Xie Shaofei , Lu Jun , Cao XiaoJian , Xiang BingRen , Ye Ye
Published: August 2008

The aim of this study was to determine the feasibility of using near infrared (NIR) spectroscopy to identify motor and sensory fascicles. Using 12 adult Beagle dogs which were anesthetised generally and sacrificed, canalis vertebralis were opened and both anterior and posterior roots were harvested from the first lumbar vertebrae to the second sacral vertebrae (L1–S2). A total of 126 anterior roots and 126 posterior roots were collected. NIR diffuse reflectance spectra were measured using a Fourier transform near infrared (FT-NIR) spectrometer fitted with a fibre-optic probe. The average spectrum of each sample was used for further analysis. There were no clear differences from the spectra between the anterior and posterior root samples. Original spectral data were transformed to second derivative spectral data. Soft independent modelling of class analogy (SIMCA) was employed to identify the anterior and posterior roots based upon differences in their spectral features. SIMCA models correctly classified 79–100% for the anterior and posterior roots and mean 83.7%. This study demonstrated that NIR spectroscopy in combination with pattern recognition methods (SIMCA) could be used to classify the anterior and posterior roots. This result suggests that NIR spectroscopy may provide a rapid, correct, non-destructive, low-cost means to quickly differentiate motor and sensory fascicles in mixed nerves.
Near Infrared Applications in the Quality Control of Seed Cotton
Authors: Gaitán-Jurado Antonio J. , García-Molina María , Peña-Rodríguez Francisco , Ortiz-Somovilla Victor
Published: August 2008

In the cotton industry the most important parameters for quality of seed cotton (unginned, harvested cotton) are moisture content and impurity level. In Spain, these quality parameters are regulated and cotton producers are awarded incentives. This study was performed to investigate the potential of near infrared (NIR) spectroscopy for determining moisture content and impurity level of seed cotton. A total of 100 cotton samples collected from eight cotton ginners were used. Two spectrometers were employed, one a research level instrument (Foss NIRSystems 6500), the other with a reduced wavelength range more suitable for use at-line (InfraXact Lab). Moisture content was measured using a moisture meter, which is used in cotton industry, and by a drying oven technique. Impurity level was determined by gravimetric analysis. Partial least square regression and classification were performed for moisture and impurity level of cotton, respectively. In sample preparation, the NIRSystems 6500 with a back cover of the sample cell was better in repeatability of spectra than the InfraXact Lab with no back cover. For moisture, the best calibration was developed by using the reference values from the oven drying method and using the first derivative and standard normal variate and detrending as pre-processing of the spectral data, giving a standard error of 0.44% in the range of 5.83-14.96% moisture content. The classification model for the impurity level was developed with a combination of first derivative and multiplicative scatter correction of the spectral data and resulted in an accuracy of 80%. For both moisture and impurity parameters, using the NIRSystems 6500 instrument gave slightly better results than using the InfraXact Lab.
An Application of near Infrared Spectroscopy to the Study of the Selenite Minerals: Chalcomenite, Clinochalcomenite and Cobaltomenite
Authors: Frost Ray L. , Reddy B. Jagannadha , Keeffe Eloise C.
Published: August 2008

The selection of five naturally occurring selenite minerals that contain two different transition metal ions, Cu2+ and Co2+ could be distinguished by near infrared spectroscopy. Dependence of composition on spectral properties is a key to mineral identification and differentiation of the members of the selenite group. The nature of the band positions and splitting of band components in the electronic spectra of Cu2+ selenites in the region 12,400–8000 cm−1 are in conformity with octahedral geometry distortion. The two split components which are observed for the Co2+ band near 9000 cm−1 in cobaltomenites are considered as the vibrational satellites of spin-allowed transition 4T1g(F)→4T2g(F). Bands observed at 6950 cm−1, 6810 cm−1 and 6700 cm−1 are the overtones of OH stretches of structural water in selenites and a strong absorption feature near 6700 cm−1 is the result of hydrogen bonding between (SeO3)2– and H2O. These bands are shifted in cobaltomenites. A sharp absorption band at 5170 cm−1 is a common feature in all the spectra of selenite minerals and is the contribution by the combinations of the OH vibrations of water molecules, ν3 and ν1. A series of overlapping bands around 4500 and 4100 cm−1 is the result of the combination of the vibrational modes of (SeO3)2– ion in the minerals.
Hyperspectral Imaging System Calibration Using Image Translations and Fourier Transform
Authors: Gorretta Nathalie , Rabatel Gilles , Roger Jean-Michel , Fiorio Christophe , Lelong Camille , Bellon-Maurel Veronique
Published: August 2008

In this paper, we describe a methodology based on imaging system shifting and Fourier transform to recover the spatial distribution of the sensivity of a hyperspectral imaging system. The methodology mainly adresses a hyperspectral imaging system based on a CCD sensor for proximity image acquisition. The principle is to look several times at the same scene by moving the camera slightly (a few millimetres) at each acquisition. Thus, it is possible to separate what moves (scene) from what remains fixed (response of the system) using properties of Fourier transform. Tests on synthetic images have reinforced theorical results on contraint shifts and given good results with more than ten translations. Tests on real and in-laboratory images have shown the need for accurate determination of translation to avoid some disruptive effects (pattern multiplication). Nevertheless, the results are promising and have shown the potential of the methodology to correct images from spatial non-uniformity due to the imaging system (radiometric aberration due to the sensor and optic). We notice that such a methodology remains valid for any imaging system based on a charged-coupled device (CCD) sensor.
Multiplex Allele-Specific Fluorescent PCR for Haplotyping the IVS8 (TG)m(T)n Locus in the CFTR Gene
Authors: Costa Catherine , Costa Jean-Marc , Martin Josiane , Boissier Brigitte , Goossens Michel , Girodon Emmanuelle
Published: August 2008

Background: Precise genotyping of the intron 8 poly(TG) and poly(T) tracts of the cystic fibrosis transmembrane conductance regulator (CFTR) gene is of clinical relevance in CFTR pathology. The (TG)m locus influences the penetrance of the (T)5 allele, which may be associated with male infertility by congenital bilateral absence of the vas deferens (CBAVD) or other CFTR-related disorders (CFTR-RD), in particular in the context of (TG)12 and (TG)13. Simple and accurate genotyping of both loci should thus be routinely offered in laboratories.

Methods: We designed a new single test method relying on multiplex allele-specific fluorescent PCR: (T)5-, (T)7-, and (T)9-specific primers, labeled with different fluorophores, in combination with a common primer. Each fluorescent PCR product was identified on a capillary sequencer by its fluorescence color, specific for (T)n, and size, indicative of the (TG) length. We first validated the assay in 2 different laboratories on 52 DNA samples with already known genotypes. We then evaluated the method prospectively, compared with sequencing, on 62 samples from healthy individuals and 108 samples from patients with CBAVD or other CFTR-RDs.

Results: We observed a 100% match in both validation steps. Results found in CBAVD and CFTR-RD patients are in keeping with data in the literature.

Conclusions: The assay proved to be simple, rapid, and accurate for single-test (TG)m(T)n genotyping and suited for analysis in clinical laboratories.
Functional and non-functional spindle formation affecting mitosis and cytokinesis in Fucus distichus zygotes: the role of the centrosome
Authors: Motomura Taizo , Nagasato Chikako
Published: August 2008

Functional (with centrioles) and non-functional (without centrioles) mitotic spindle formation was studied in Fucus distichus zygotes. In normally fertilized zygotes, a pair of centrioles derived from sperm existed at both mitotic poles. Both centrin and γ-tubulin were associated with centrioles. In multipolar spindles of fertilized multinucleate eggs, mitotic poles with centrioles were stained with an anti-γ-tubulin antibody, but the other poles were not, and cytokinesis proceeded abnormally. When karyogamy was blocked with colchicine, centrioles remained around the sperm nucleus. A monastral spindle or a bipolar, barrel-shaped spindle was formed on the egg nucleus; however, there were no centrioles at these mitotic poles. When cytoplasmic fragments containing only an egg or a sperm nucleus were separately prepared and cultured, the egg nucleus appeared to enter, but did not complete, mitosis. In cytoplasm containing only a sperm nucleus, mitosis and cytokinesis did not occur. We concluded that the egg nucleus has the potential to form a non-functional spindle without the sperm centrioles. However, this acentrosomal spindle was non-functional; mitosis remained at the stage of chromosome condensation and did not proceed to cytokinesis. Even though some cells proceeded to cytokinesis, they showed abnormal chromosome condensation.
Embodying Utopia: Charisma in the post-Mao Qigong Craze
Authors: Palmer David A.
Published: August 2008

This article discusses the dynamics of charismatic religious movements through the case of the qigong craze, which was the largest mass spiritual/religious movement in urban China in the 1980s and 1990s, until the banning of Falun Gong in 1999. Charisma can be apprehended at three levels: as the embodied experience of individuals; as the emotional affect between masters and followers; and as a collective movement within a macro-social context. This article examines the articulation between these three dimensions of the charismatic phenomenon, tracing how, through breathing and meditation exercises, the masters teaching them and the organizations promoting them, charismatic experiences could be generated within and between millions of individual bodies and articulated with utopian expectations at a specific juncture of modern Chinese history. The emic notion of qi as an objectified power that can be experienced, manipulated, and produced is discussed, showing how it both facilitated the emergence of charisma but prevented its consolidation, leading groups based on qi experiences towards post-charismatic outcomes of commodification, radicalization or traditionalization.
Influence of processing route and SiO2on sintering ability, CTE, and dielectric constant of β-Si4Al2O2N6
Authors: Ganesh Ibram , Thiyagarajan N. , Jana D.C. , Sundararajan G. , Olhero S.M. , Ferreira J.M.F.
Published: August 2008

Dense β-Si4Al2O2N6and β-Si4Al2O2N6-0.5SiO2ceramics were obtained from α-Si3N4, α-Al2O3, AlN, and Y2O3upon sintering green bodies consolidated by aqueous gel casting. For comparison purposes, a β-Si4Al2O2N6was also prepared by the conventional dry-powder processing route. In the case of gel-cast β-Si4Al2O2N6, the as-purchased AlN powder was treated with H3PO4and Al(H2PO4)3prior to use along with α-Si3N4, α-Al2O3, and Y2O3. The gel-cast β-Si4Al2O2N6exhibited superior hardness (1423 ± 6 Hv), fracture toughness (3.95 ± 0.3 MPa⋅m1/2), and coefficient of thermal expansion (CTE) (3.798 × 10−6/°C between 30 and 1000 °C) in comparison to the ceramic consolidated by conventional dry pressing, which exhibited only 1317 ± 5 Hv, 3.30 ± 0.2 MPa⋅m1/2, and 3.532 × 10−6/°C between 30 and 700 °C. The in situ-generated ∼9 wt% SiO2has considerably reduced the dielectric constant and CTE of β-Si4Al2O2N6from 7.30 to 6.32 and from 3.798 × 10−6/°C to 3.519 × 10−6/°C, respectively. The loss tangent property of the investigated materials was little influenced by the variation of chemical composition and processing route.
Electromigration and thermomigration behavior of flip chip solder joints in high current density packages
Authors: Yang D. , Chan Y.C. , Wu B.Y. , Pecht M.
Published: August 2008

The electromigration and thermomigration behavior of eutectic tin-lead flip chip solder joints, subjected to currents ranging from 1.6 to 2.0 A, at ambient temperatures above 100 °C, was experimentally and numerically studied. The temperature at the chip side was monitored using both a temperature coefficient of resistance method and a thermal infrared technique. The electron wind force and thermal gradient played the dominant role in accelerated atomic migration. The atomic flux of lead due to electromigration and thermomigration was estimated for comparison. At the current crowding region, electromigration induced a more serious void accumulation as compared with thermomigration. Also, because of different thermal dissipations, a morphological variation was detected at different cross-sectional planes of the solder joint during thermomigration.
Reaction mechanism of self-propagating high-temperature synthesis reaction in the Ni–Ti–B4C system
Authors: Yang Y.F. , Wang H.Y. , Zhao R.Y. , Liang Y.H. , Jiang Q.C.
Published: August 2008

The SHS reaction in the Ni–Ti–B4C system starts with the formation of Ni–Ti and Ni–B intermetallic compounds from the solid interacted reaction among the reactants and, subsequently, the formation of Ni–Ti and Ni–B liquid at the eutectic point. Meanwhile, some C atoms from the reaction between Ni and B4C can dissolve into Ni–Ti liquid to form TiC. The heat generated from these reactions can promote the mutual diffusion of Ni–Ti–C and Ni–B liquid and simultaneously accelerate the formation of Ni–Ti–C–B liquid. Finally the precipitation of TiC and TiB2 occur when the C and B atoms in the liquid become supersaturated. The addition of Ni not only promotes the occurrence of the self-propagating high temperature synthesis (SHS) reaction by forming Ni–Ti liquid, but also accelerates the SHS reaction by forming Ni–B liquid and dissociative C. The early appearance of dissociative C from the reaction between Ni and B4C causes the formation of TiC prior to that of TiB2.
Investigation of Polymer Adsorption on Rock Surface of High Saline Reservoirs
Authors: Amro Mohammed M.
Published: August 2008

Blocking or reducing water production from oil wells has to be considered as a serious problem in oil industry. In order to reduce the water relative permeability in the reservoir, there is the possibility of envisaging polymer flooding. Moreover and, owing to the phenomenon of adsorption of polymers on the rock surface, the existing heterogeneities within the reservoir can be reduced. In this study, two types of polymers namely; polyacrylamide (PAA) and polysaccharides (xanthan) have been investigated. The viscosity of both polymer solutions was first evaluated based on different salinities, shear rates and concentrations. The prepared solutions were then injected into core samples. Such process was aimed to examine the adsorption on rock surface by calculating the resistance factor as well as the residual resistance factor. Moreover, the effect of the injection rate of polymer solution has also been studied. As a result, it has been found that xanthan solution is tolerant of high salinity (20%), while PAA-solution is very sensitive to salt. Furthermore, such statement matches also the temperature which can reach till 60°C. It is also found that the lower the injection rate the higher is the adsorption on rock surface. Therefore, xanthan can be recommended to water shut off in high salinity and high temperature reservoirs.
A New Deep Azimuthal Resistivity LWD for Optimal Well Placement and Reservoir Exploitation; Successful Validation with Saudi Aramco
Authors: Palmer Richard , Silva Andre , Hajari A. A. , Bittar Michael , Shokeir Ramez , Lotfy Amr , Chemali Roland
Published: August 2008

Optimal well placement seeks to achieve two seemingly contradictory objectives. For the short term, the well needs to establish the longest possible contact with the productive zone in order to enhance early production. For the long term production strategy of the field, the challenge is to maximize the total volume of hydrocarbon produced during the life of the field.

The first objective can be readily achieved by staying away from all reservoir boundaries at all times; this includes the oil-water contact and the cap rock for an oil reservoir. The second objective requires, depending on the situation, that the well be placed immediately below the cap rock, immediately above the oil-water contact, or at some predefined distance away. Precise well placement and proactive geosteering are required to achieve both objectives simultaneously.

A new azimuthal deep resistivity LWD device was recently evaluated and field tested in a field in Saudi Arabia. The stated objective of the run was to measure resistivity azimuthally and to assess the electrical anisotropy in the reservoir. In addition to anisotropy and resistivity determination, memory data was acquired in the process and later used to simulate situations in the field where real time geosteering decisions were required.

The up-down phase propagation logs gave a visual indication of the approaching boundaries, showing whether to expect it from below or above the well. The additional deep Geosignal measurement provided an early warning of the approaching boundaries long before the actual intersection was confirmed by borehole imaging. Multiple images at three depths of investigation showed progressively a bed of interest entering sequentially into the fields of investigation of the various measurements. Quantitative distance-to-bed boundary also helped derive the rate of approach of the boundary. Combined with images at different depths of investigation and with up-down resistivity, the information enabled informed real time decision-making for evasive action and proactive geosteering in future deployments.
Comprehensive Reservoir Characterization with Multiphase Production Logging
Authors: Al-Muthana Ahmed S. , Ma S. M. , Zeybek M. , Malik Shauket
Published: August 2008

Currently, many of the producers are horizontal wells and a considerable number of them are equipped with smart complex completions. Evaluating the performance of these horizontal producers is critically important for improved reservoir management. Conventional production logging tools cannot meet the challenges of logging horizontal wells, especially in multiphase flow. A new logging tool has been specifically designed to better characterize fluid flow in horizontal wells. Advanced sensors provide better resolution among gas, oil, and water and cover more cross sectional areas of a wellbore for enhanced characterization of multiphase flow regimes. The new tool is also more compact to pass through intervals that have high dog legs.

In this paper we will briefly review the new technologies available today for production logging, with examples of evaluating horizontal wells with barefoot smart completions, diagnosing water entries, flow profiles and fluid break-through. Production flow profiles are also used for identifying geological features such as super permeable zones or fractures. Well performance evaluation shows that the integration of the flow profiles, well performances and all other reservoir data provided improved reservoir characterization and better well production strategies.
Economical Modeling of CO2 Capturing and Storage Projects
Authors: Algharaib M. , Al-Soof N. Abu
Published: August 2008

Recently, there is a rising global attention to reduce carbon dioxide (CO2) emissions from fossil fuels burning due to environmental considerations. Conversely, there is a growing interest in oil industry to utilize CO2 in Enhanced Oil Recovery methods (EOR) to cope with the high oil demands in main consuming countries. Synchronization between these two sides is promising through the applications of CO2-EOR projects. Generally, there are five economical constituents of most CO2-EOR projects: CO2 capturing cost, CO2 compression cost, CO2 transportation cost, CO2 storage cost, and revenue enhancement through increasing oil production. Economical evaluation of CO2-EOR projects is a crucial measure in order to insure project’s viability.

In this study, an efficient and fast model was developed to predict the economics involved in CO2-EOR projects. The developed model consists of five modules that predict the major economical constituents of CO2-EOR projects.

The model was used to predict the economics involved in capturing and storing CO2 in a Middle Eastern reservoir which is recommended for miscible CO2 flooding. The results showed that due to the level of the immature development of the reservoir, CO2 storage activities, such as drilling new wells and preparing the field for injection, constituted most of the expenditures. Moreover, the model was subjected to sensitivity analyses to evaluate the effects of several parameters on the various cost components encountered in CO2-EOR projects and the net present value. The results indicated that the investigated parameters can be divided into five different groups according to their influence. The results also showed that recycling the produced CO2 has a significant impact on the economics of CO2-EOR projects. Finally, the effect of capturing CO2 from different types of power plants on the capturing cost was investigated.
Multidisciplinary Challenge for Microbial Enhanced Oil Recovery (MEOR)
Authors: Amro Mohammed M.
Published: August 2008

Microbial enhanced oil recovery (MEOR) is one of the recent techniques suggested to stimulate oil production. This technique is based on in situ growth and metabolism of selected microorganism in the reservoir rock with certain nutrients. The microorganisms produce gases and/or chemicals in the formation such as polymer, acids, gases and surfactants. Production of these chemicals in the formation changes fluid and rock properties of the reservoir and improves the sweep efficiency. This change respectively increases the oil production from the reservoir.

This paper presents the methods to find out about suitable bacteria, the assessment of their oil mobilizing abilities and the determination of the responsible mechanisms for oil mobilization. In addition, the effect of different reservoir parameters on the growth of microorganisms was investigated. Flooding experiments were carried out under reservoir conditions, in order to verify the ability of bacteria strains to mobilize residual oil in place and to detect the oil mobilizing mechanisms.

Important mechanisms leading to oil recovery by microorganisms are found. Moreover, the most important screening criteria for the application of Microbial Enhanced Oil Recovery (MEOR) in any field are included. Achievements of this project have been found also and strongly on the involvement of other disciplines. Among those branches are; microbiology, chemistry and of course petroleum engineers. This interdisciplinary challenge has been set up for better result improvements.
New Hydrogen-Resistant Optical Fibre for Harsh Environments
Authors: Hawthorne W. D. , Ramos R. T.
Published: August 2008

Distributed temperature sensing (DTS) has now become an established method for collecting permanent real-time temperature logs of wells. The applications include real-time production-allocation, heavy oil thermal recovery (e.g., steam-assisted gravity drainage, SAGD) and steam-well management, and well-integrity monitoring. One issue that has been limiting the lifetime of such systems is degradation of the optical fibres that are used as the sensing element. The main mechanism of long-term deterioration is the increase in optical losses due to attack of the optical-fibre glass by hydrogen. The presence of hydrogen within the core of both single- and multimode optical fibres can cause significant problems, specifically high attenuation across a broad wavelength span, and this can reduce the efficiency of an optical fibre to transmit data or be used as a sensor. Depending upon the ambient temperature, this attenuation can be permanent.

This article discusses the testing of a new type of optical fibre that is much less susceptible to hydrogen-induced failure. The performance of this fibre in high-temperature hydrogen tests is presented and this fibre is shown to be at least an order-of-magnitude more resistant to hydrogen deterioration than other commercially available optical fibres under controlled laboratory conditions. Field-test results in harsh conditions are in agreement with the experimental observations.

This is a significant technological advance that will increase the reliability of DTS systems. The much-improved performance at high temperatures will also increase the range of applications in the oil and gas industry, including steam-flood recovery in extreme environments; high-pressure, high-temperature permanent monitoring; and other related thermal methods.
I-Field Capabilities Enable Optimizing Water Injection Strategies in Saudi Arabian Newly Developed Oil Fields
Authors: Al-Malki Said , Buraikan Meshal M. , Abdulmohsin Rami A. , Ahyed Rabea , Al-Hamzani Housam
Published: August 2008

This paper demonstrates how I-Field capabilities were used to monitor in real time pre-injection performance of eight reservoirs across the three AFK fields. Focus will be on illustrating one I-Field workflow used to monitor injection from real time data gathering, validation, and mapping using Permanent Downhole Monitoring Systems (PDHMS), and integrated surface & subsurface modeling and data mapping packages. Additionally, the paper will address how integrated real time data and modeling results are used to optimize injection strategy for the three fields for more efficient real time reservoir management.
2005 Poliovirus eradication: poliovirus presence in Cyprus 2 years after
Authors: Richter Jan , Bashiardes Stavros , Koptides Dana , Tryfonos Christina , Pissarides Nikolas , Stavrou Niki , Papageorgiou Georgos T. , Christodoulou Christina
Published: August 2008

The last case of polio in Cyprus caused by a wild-type poliovirus occurred in 1995. Since then Cyprus belongs to the countries considered poliovirus-free by the WHO. The aim of this study was to confirm the absence of any circulating wild-type polioviruses and to monitor vaccine-derived polioviruses in Cyprus by analysis of sewages. During the course of this study no wild-type polioviruses were identified, although the identification of viable oral poliovirus vaccine isolates confirmed the presence and circulation of poliovirus vaccine strains in sewage in Cyprus.
Comparison of two molecular methods used for subtyping of Legionella pneumophila 1 strains isolated from a hospital water supply
Authors: Casini B. , Valentini P. , Baggiani A. , Torracca F. , Lorenzini C. , Frateschi S. , Matteoli B. , Privitera G.
Published: August 2008

The results of the pulsed-field gel electrophoresis and the sequence-based typing (using the loci flaA, pilE, asd, mip, mompS and proA) were compared for subtyping of Legionella pneumophila 1 strains isolated from a hospital water supply. Molecular typing was carried out on 61 isolates (38% of the positive samples) selected on space and temporal criteria in order to follow the evolution of the water-system colonization. For all the 61 isolates, the sequence of the amplified mip gene fragment identified Legionella pneumophila strain Wadsworth. Genotype testing by PFGE analysis showed three different patterns, correspondent to three SBT types according to the allelic profiles. Both PFGE and SBT indicated the circulation and the persistence in the hospital potable water-system of three types randomly distributed in space and time. The two molecular methods adopted showed a 100% concordance, although a low degree of genetic heterogeneity characterized the isolates. The electrophoretic patterns were sufficiently unambiguous to consider PFGE a highly discriminatory typing method, but the SBT technique besides accurately characterizing isolates, was able to identify Legionella strains through analysis of the mip gene. A typing method with this level of discriminatory power has great potential for assisting in epidemiological studies.
Getting ready for climate change implications for the western USA
Authors: Standish-Lee P. , Lecina K.
Published: August 2008

Water users throughout the western United States have faced supply problems from the conception of modern civilization. Today, climate change, population growth, and declining water quality combine with the age-old problem of finding sufficient water resources in a region with a largely arid climate. Climate change in particular poses a significant threat to the sustainability of water supplies in the western United States (the West). Casting aside all debate about who and what is responsible for climate change, the public and water utilities alike must be prepared to address its effects on water supplies.
Estimating Reach via Visual Imagery and Motor Imagery
Authors: Gabbard Carl P , Cordova Alberto
Published: August 2008

With the present study we compared the use of motor imagery (MI) and visual imagery (VI) in estimating reach. There are indications that with MI there is a visual (action) processing advantage. Alternatively, one could speculate that due to a lifetime of experience with reaching within one's peripersonal space, the difference between imagery techniques would be minimal. Adult right-handers performed estimates of reach via VI and MI at multiple locations in peripersonal and extrapersonal midline space. Data analysis indicated a distinction in which participants were more accurate when using MI. In addition to the basic science nature of these findings, there are possible implications for imagery methodology used in sport and clinical settings.
Optimal Fiscal Policy When Migration Is Feasible
Authors: Occhino Filippo
Published: August 2008

This paper investigates how the feasibility of migration affects governments' optimal fiscal policies. We assume that households migrate toward economies where their welfare is higher, governments choose taxes and public expenditures to maximize a weighted sum of the households' welfare, welfare is increasing in public expenditures, and only distortionary labor income taxes are available. In isolated economies, the optimal fiscal policy implies that some households are net fiscal contributors, while other households are net fiscal beneficiaries. When households can migrate, however, governments compete for the households which are net fiscal contributors, and modify the fiscal policy in their favor, lowering their taxes and net fiscal contribution, and increasing their welfare. The magnitude of the effect increases with the sensitivity of migration to welfare. In the limiting case of free mobility, all households are zero net fiscal contributors. As to the patterns of migration, the model predicts that, with high migration costs, all households migrate toward the same high-productivity countries, which benefits low-productivity households, whereas with low migration costs, households with different productivities migrate toward different countries, which benefits high-productivity households.
How to Optimize Learning From Animated Models: A Review of Guidelines Based on Cognitive Load
Authors: Wouters Pieter , Paas Fred , van Merriënboer Jeroen J. G.
Published: August 2008

Animated models explicate the procedure to solve a problem, as well as the rationale behind this procedure. For abstract cognitive processes, animations might be beneficial, especially when a supportive pedagogical agent provides explanations. This article argues that animated models can be an effective instructional method, provided that they are designed in such a way that cognitive capacity is optimally employed. This review proposes three sets of design guidelines based on cognitive load research: The first aims at managing the complexity of subject matter. The second focuses on preventing activities (attributed to poor design) that obstruct learning. The last incites learners to engage in the active and relevant processing of subject matter. Finally, an integrative framework is presented for designing effective animated models.
Energy Product Options for Eucalyptus Species Grown as Short Rotation Woody Crops
Authors: Rockwood Donald L. , Rudie Alan W. , Ralph Sally A. , Zhu J. Y. , Winandy Jerrold E.
Published: August 2008

Eucalyptus species are native to Australia but grown extensively worldwide as short rotation hardwoods for a variety of products and as ornamentals. We describe their general importance with specific emphasis on existing and emerging markets as energy products and the potential to maximize their productivity as short rotation woody crops. Using experience in Florida USA and similar locations, we document their current energy applications and assess their productivity as short-term and likely long-term energy and related products.
Redox Behavior of Anticancer Chalcone on a Glassy Carbon Electrode and Evaluation of its Interaction Parameters with DNA
Authors: Shah Afzal , Khan Asad M. , Qureshi Rumana , Ansari Farzana L. , Nazar Muhammad F. , Shah Syed S.
Published: August 2008

The interaction of anticancer chalcone [AMC, 1-(4'-aminophenyl)-3-(4-N,Ndimethylphenyl)- 2-propen-1-one] with DNA has been explored using electrochemical, spectroscopic and viscometric techniques. A shift in peak potential and decrease in peak current were observed in cyclic voltammetry and hypochromism accompanied with bathochromic shift were noticed in UV-Vis absorption spectroscopy. These findings were taken as evidence for AMC –DNA intercalation. A binding constant (K) with a value of 6.15 × 105 M-1 was obtained from CV data, which was also confirmed by UV-Vis absorption titration. Moreover, the diffusion coefficient of the drug with and without DNA (Db and Du), heterogeneous electron transfer rate constant (ko) and electron affinity (A) were also calculated from electrochemical data.