bluuebunny/crossref_metadata_2025 huggingface dataset:
Obagi – Present and Future Challenges of a Mature Oil Field
Authors: Guillonneau N. , Fontaine G. , Gory J. Y. , Iwuoha S. , Ahmed H. , Ekpenyong D.
Published: December 2009

OBAGI is an onshore oil field located on OML58, 85 km north-west of Port-Harcourt, Nigeria. It is composed of 26 stacked reservoir levels with an estimated total OOIP of 1.2 Gbbls. It was discovered in 1964 and has been producing since 1966 through 123 wells and 257 completions. 21 layers have been developed.

With a global recovery to-date of 50% and an average producing water-cut of 75%, OBAGI can be considered as a mature oil field. Current activities are driven by two main objectives: to sustain short term production level, andto identify potential remaining resources for additional developments

Appropriate monitoring and global static/dynamic review are the key factors to achieve these objectives.

The short term objective is to maintain production by optimizing the injection capacity. Difficulties to model reservoir performance have resulted in implementation of an intensive monitoring program. This is to limit water production and to maintain/increase water injection capacity.

For the long term, it is believed that potential resources not accessible with current wells could effectively double the remaining reserves. For this purpose, complementary developments have to be proposed to target clearly identified attic oil or bypassed regions. A pragmatic approach was adopted based on 2G model review, material balance study and fluid contact updates (with regular saturation survey campaigns) to identify additional reserves potential.

The progress of the study is presented for one of the layers of the field.
A System Approach to Enhance Offshore Drilling and Production
Authors: Polito Sergio , Brambilla Mauro , Dall’Aglio Dario
Published: December 2009

The main design criteria of an innovative semisubmersible drilling rig are presented. Among other distinctive features, the "functional availability" is illustrated as the most effective fault tolerance systemic approach of the state of the art. The basic tool to implement functional availability is the "Fault isolation through distribution" with ensuing beneficial effects bot technical and economical on the major onboard systems.

Consistent, reliable performance quality-level and overall operational safety enhancement are the direct result of such an approach, alongside with a substantial increase of operational flexibility.

This applies as well to the easy and quick conversion of the rig into an early production unit (and back) in P modes:

Production & Drilling Mode, keeping drilling equipment onboard with a 40 - 60,000 BBPD oil production capacity

Production Only Mode, removing main drilling equipment, with a resulting oil production capacity of 80 - 110,000 BBPD, without considering possible associated gas.

The unit has been designed to fully comply with the stringent Norwegian Petroleum Directorate rules for floating production units, including all extra requirements for fire protection (also structural).

A modular approach to production and drilling equipment and facilities enhances easy, safe, quick installation & removal.

Finally a concise description of the technical nature of the maiden assignement of the rig is supplemented, with a variety of operational duties on the Snorre Field off Norway, which could extended, from 1990, untill 1998.
Delivering BP North Sea's Longest OHGP Completion in the Harsh Environment Deepwater West of Shetlands
Authors: White D. , Wilson A. , Roy A. , Stewart S. , Woudwijk R. , Nadeem A.
Published: December 2009

The BP Operated Foinaven, Schiehallion and Loyal fields, located West of Shetland (WoS) in the UKCS, are a highly challenging environment to work in. The three deepwater fields are drilled and completed utilising 4th generation semi-submersible rigs and the harsh marine environment can severely impact operations.

Although standalone screen completions have been used successfully in the majority of the wells, premature sanding problems have been experienced, potentially jeopardizing project economics due to prohibitively high cost of remediation. To improve this situation, alternative means of sand control completions have therefore been sought. There are now four Open Hole Gavel Pack (OHGP) completions in the fields, all of which are performing well with high productivities and no sand production.

In this paper, we present a case history on the application of the circulating water pack in the Foinaven field. The P11 sidetrack is the third gravel pack completion in this deepwater environment, and the first to be completed with a water pack. The subject well is the longest OHGP in BP's North Sea portfolio with a 3,345 ft open hole, penetrating through two sand bodies and multiple shale and mudstone packages.

The well was designed with a long horizontal open hole section to cost-effectively access multiple sand bodies and maximise productivity while minimising drawdown across the sandface. Baker Oil Tools BetaBreaker technology was utilised for the completion to maintain the treatment pressure below the reservoir fracture gradient during the gravel pack. The well was completed with a +110% packing efficiency, has an early time mechanical skin of +2 based on pressure buildup testing and was delivered safely 5 days ahead of target at P(10) production expectations.
Regulation of Macrophage Homeostasis
Authors: L Bonfield Tracey
Published: December 2009

Macrophages contribute to both initiation and resolution of inflammatory processes.
These cells of diverse functional activity participate as both effectors and affectors in host tissue
development, homeostasis and response to injury. Survival and function of the macrophage is
dependent on colony stimulating factors granulocyte colony stimulating factor (GM-CSF) and
macrophage colony stimulating factor (M-CSF). These colony stimulating factors play a significant
role in defining the phenotype and activity of macrophages through regulating the expression of
transcription factors PU.1 and peroxisome proliferator activator receptor gamma (PPARγ). Recent
data suggests that alveolar macrophages are not passive participants in immune responses and that
the status of “macrophage activation” defines the phenotype of the ensuing innate and adaptive
responses. The status of alveolar macrophage activation, including cytokine production,
phagocytosis, and antigen presentation, orchestrates the intensity and duration of the immune
response. This chapter summarizes the perspectives of colony stimulating factor regulation of
macrophage activity in immunity and pulmonary homeostasis.
Critical Clearance: Alveolar Macrophage Recognition of Apoptotic Cells
Authors: Anne Ogden Carol
Published: December 2009

Apoptotic cell clearance is a vital process by which the body rids itself of unwanted
cells, whether they become unwanted due to age, senescence, tissue remodeling and repair, or even
damage. Efficient clearance of apoptotic cells depends upon the ability of the phagocyte to
recognize and quickly engulf the effete cell before the apoptotic cells can progress to a state of
secondary necrosis, spilling out phlogistic and possibly auto-immunogenic contents into the tissue.
Removal of apoptotic cells in the lung by alveolar macrophages results in the maintenance of
homeostasis, and alveolar macrophage recognition factors control process of clearance.
Defective Clearance of Apoptotic Cells (Efferocytosis) in Chronic Lung Diseases
Authors: Hodge Sandra
Published: December 2009

Repair of airway epithelial injury and resolution of inflammation are highly regulated
processes. Inefficient clearance of apoptotic cells (efferocytosis) has the potential to cause an
accumulation of apoptotic material and the subsequent development of secondary necrosis and
perpetuation of chronic inflammation. Alveolar macrophages have the major role in effectively
clearing excess apoptotic cells in the airway. Several studies have identified defective efferocytosis
in the airways of subjects with chronic pulmonary diseases including chronic obstructive pulmonary
disease (COPD), asthma, lung cancer and cystic fibrosis. These defects have been shown to at least
partially relate to reduced levels of soluble mediators including mannose binding lectin (MBL) and
collectins (surfactant proteins A and D), as well as dysregulated expression of various macrophage
surface receptors and molecular pathways. These defects in macrophage function are potential
targets for new therapeutic interventions for chronic lung diseases.
Role of Macrophage Phagocytosis of Bacterial Pathogens in Chronic Lung Disease
Authors: E Taylor Abigail , E Donnelly Louise
Published: December 2009

The increasing prevalence of inflammatory lung disease is becoming a major heath
burden. Chronic inflammation is a key feature of asthma, chronic obstructive pulmonary disease
(COPD) and cystic fibrosis. These patients are prone to bacterial pathogens that contribute to
disease worsening. The reasons for this are unclear but may reflect defective pathogen clearance by
alveolar macrophages. For example, alveolar macrophages from patients with COPD have a educed
capacity to phagocytose bacteria and hence promote pulmonary bacterial colonisation. In cystic
fibrosis macrophages are also defective in removing bacteria and this coupled with reduced
acidification of the phagosome implies that macrophages contribute to ineffective bacterial uptake
and subsequent killing. Bacteria can also employ diverse strategies to subvert the macrophage
phagocytic pathway. For example, the capsule of Streptococcus pneumoniae prevents opsonisation
by complement proteins and therefore is not removed efficiently by macrophages. Understanding
the mechanisms underlying exacerbations of lung diseases will provide novel treatment strategies
that will be of benefit for the patients in the short-term but could also prevent the acceleration of the
disease process that is often associated with frequent exacerbations and ultimately improve the
quality of life for patients already living with debilitating disease.
Novel Therapeutic Approaches to Improve Efferocytosis for Pulmonary Disease
Authors: N. Reynolds Paul
Published: December 2009

There is growing appreciation for the potential role of defective clearance of apoptotic
cells by macrophages in disease pathogenesis. This has naturally lead to the consideration that
therapies directed towards improving phagocytosis may have therapeutic utility. Some of these
candidate therapies are already in use, although their initial rationale was for reasons other than
improving phagocytosis. Examples are macrolide antibiotics, which are known to have antiinflammatory
activities beyond their antimicrobial roles. In certain conditions (panbronchiolitis)
these agents have become first-line therapy. Subsequent studies have revealed that at least part of
their beneficial effects may be mediated via improvements in macrophage function. Statins and
glucocortocosteroids also appear to act in part via improved phagocytosis. More recently, strategies
are being pursued that are more specifically directed towards macrophage function, such as the use
of mannose-binding lectin, but the initial rationale was to improve phagocytosis of microorganisms
– the potential role in effercytosis has been realised subsequently. We have conducted a
number of human and animal studies which support the potential role for improving phagocytosis as
a therapeutic strategy for airways disease. A number of new strategies are emerging which show
clinical promise.
Preliminary Concepts
Authors: Izadi F. A.
Published: December 2009

For the purpose of being self-contained, the book starts with some elementary topics.
These include the definition of various standard sets, some basic combinatorial definitions and identities,
introducing complex numbers and their arithmetic properties, in particular de Moivre formula and the
nth roots of a complex number. The case of square root gives rise to an elegant formula for the root of
the real number of the form a± √b. The next two sections are devoted to the definitions and properties
of matrices and determinants, the solutions of the linear system of equations as well as the formulas for
some special determinants, in particular the Vandermonde determinant. Finally, the closing remark of the
chapter is the definition of a function which plays an important role in discrete calculus. Because of its
relation to the arrangement formula it is called "the arrangement power function".
Boundary Value Problems
Authors: Izadi F. A.
Published: December 2009

The theory of discrete value problems and their connections to the spectral theory of
operators are discussed in this chapter. These problems can be interpreted as the discrete analog of the
mathematical physics equations in one dimension. These include auxiliary problem scheme, coincidence
condition of a boundary value problem on its auxiliary problem, the type of problems coinciding with
their auxiliary problems, the necessary condition for existence of the boundary value problem and finally
the boundary value problem on an infinite domain.
Appendix A 2-Variable Discrete Analysis
Authors: Izadi F. A.
Published: December 2009

This chapter deals with ten different problems. Except for the three sections; namely an
unsolved problem about a cubic root of a complex number, symmetric derivative, and the spectral de-
composition of a matrix by a projection matrices, all other sections are devoted to the discrete analysis of
complex valued functions. Topics included are the discrete partial derivatives of complex valued functions,
the Cauchy theorem, Laplace equation, Cauchy-Riemann discrete differential equations, complex integra-
tion and above all, the most important concept which brings all these together, is the discrete analog of
analytic functions in complex analysis.
Bibliography
Authors: Izadi F. A.
Published: December 2009

Full Text Available.
Index
Authors: Izadi F. A.
Published: December 2009

Full Text Available.
NUT Midline Carcinoma in a Newborn with Multiorgan Disseminated Tumor and a 2-Year-Old with a Pancreatic/Hepatic Primary
Authors: Shehata Bahig M. , Steelman Charlotte K. , Abramowsky Carlos R. , Olson Thomas A. , French Christopher A. , Saxe Debra F. , Ricketts Richard R. , Katzenstein Howard M.
Published: December 2009

NUT midline carcinoma (NMC) is a rare and aggressive malignant epithelial tumor defined by rearrangement of the NUT gene on chromosome 15. In two thirds of cases, NUT is involved in a balanced translocation with BDR4 on chromosome 19, while in the remaining cases, NUT is rearranged with variant fusion partners such as BRD3. These undifferentiated tumors primarily affect midline structures, usually in the upper aerodigestive tract and mediastinum. Most reported cases have followed a rapidly lethal clinical course. We report the clinical and pathological findings of NMC in the youngest patients identified so far. The 1st case involves a newborn who presented with a supraorbital mass and extensive multiorgan involvement, including the spine, lungs, liver, pancreas, adrenal glands, and subcutaneous tissue. The 2nd patient was a 2-year-old male with an abdominal mass involving the liver and pancreas with pulmonary metastasis. Histopathological analysis of both tumors showed undifferentiated malignant neoplasms, and immunohistochemistry showed positivity for epithelial markers. Both tumors demonstrated t(15;19), and immunohistochemistry with NUT monoclonal antibodies and fluorescent in situ hybridization confirmed NUT rearrangement. The patients died from disease at 1 and 2 months postpresentation. Thus far, 25 cases have been reported, including our 2 current cases. Presentation ages range from 0 to 78 years (mean, 23 years). Herein, we report the 2 youngest reported cases of NMC, including the 1st congenital case and the 1st case arising within the liver/pancreas. Increased awareness and further molecular studies are required for a better understanding of NMC pathobiology and improved therapeutic outcomes.
The use of ultrasonic treatment for improvement of metrological performance of sorption atomic absorption determination of lead(II) and cadmium(II) traces
Authors: Alemasova Antonina , Belova Elena
Published: December 2009

The optimal parameters for ultrasonic treatment (frequency 200–300 kHz, intensity 2–4 W cm−2) were obtained to intensify Pb(II) and Cd(II) sorption concentration by carbon sorbent from apricot pit. The combined action of ultrasonic frequency of 18 kHz and 1 MHz on concentrate slurry increases its sedimentation stability from 3 to 180 minutes and decreases Sr value up to 7% at Pb(II), Cd(II) hybrid sorption atomic absorption determination in natural waters, brines, common salt.
Synthesis and biological screening of octasubstituted-triphenodioxazines and its sulphur analogues with some novel intermediates
Authors: Heda Lalchand , Pareek Chandresh , Pareek Dushyant , Mosalpuri Sonraj
Published: December 2009

Attempts have been made to prepare for the first time the octasubstituted-triphenodioxazines and triphenodithiazines heterocycles by cyclisation of 3,6-dichloro-2,5-bis(2′,4′,5′-trichloroanilino)-1,4-benzoquinone and condensation. This wasfollowed by cyclisation of substituted 2-aminobenzenethiol respectively with chloranil and bromanil in ethanolic solution of fused sodium acetate in the presence of benzoyl chloride in nitrobenzene. Their structures were confirmed on the basis of their chemical and spectral analyses. Moreover, the biological activity of these compounds was evaluated against the test organisms viz — E.coli, S. aureus, B. subtilis, M.luteus and C. albicans. These compounds synthesized from 2,4,5-trichloroaniline appeared to possess significant antimicrobial activities and an explicit correlation between structure and biological activity was also observed.
The difference in stability between 5′R and 5′S diastereomers of 5′,8-cyclopurine-2′-deoxynucleosides. DFT study in gaseous and aqueous phase
Authors: Karwowski Boleslaw
Published: December 2009

Oxidatively generated damage to DNA frequently appears in the human genome as an effect of aerobic metabolism or as the result of exposure to exogenous oxidizing agents. Due to these facts it has been decided to calculate the stability of 5′,8-cyclo-2′-deoxyadenosine/guanosine (cdA, cdG) in their 5′R and 5′S diastereomeric forms. For all points of quantum mechanics studies presented, the density functional theory (DFT) with B3LYP parameters on 6-311++G** basis set level was used. The calculations showed a significant negative enthalpy for glycosidic bond cleavage reaction for cationic forms and slightly negative for neutral ones. The preliminary study of the discussed process has shown the nature of stepwise nucleophilic substitution DN*AD type mechanism. Surprisingly, the different values in free energy, between short-lived oxacarbenium ion intermediates, have been found to lie over a relatively small range, around 1 and 2.8 kcal mol−1. For anions, the decomposition enthalpies were found as positive in aqueous phases. These theoretical results are supported by the formic acid hydrolysis experiments of both diastereomers of cdA, for the first time. (5′S)cdA exhibited higher stability than (5′R)cdA.
Formation of amyloid-like aggregates through the attachment of protein molecules to a Congo red scaffolding framework ordered under the influence of an electric field
Authors: Stopa Barbara , Piekarska Barbara , Konieczny Leszek , Król Marcin , Rybarska Janina , Jagusiak Anna , Spólnik Paweł , Roterman Irena , Urbanowicz Barbara , Piwowar Piotr , Lewiński Krzysztof
Published: December 2009

This study describes a technique which makes it possible to introduce the amyloid-like order to protein aggregates by using the scaffolding framework built from supramolecular, fibrillar Congo red structures arranged in an electric field. The electric field was used not only to obtain a uniform orientation of the charged dye fibrils, but also to make the fibrils long, compact and rigid due to the delocalization of pi electrons, which favors ring stacking and, as a consequence, results in an increased tendency to self-assemble. The protein molecules (immunoglobulin L chain lambda, ferritin) attached to this easily adsorbing dye framework assume its ordered structure. The complex precipitating as plate-like fragments shows birefringence in polarized light. The parallel organization of fibrils can be observed with an electron microscope. The dye framework may be removed via reduction with sodium dithionite, leaving the aggregated protein molecules in the ordered state, as confirmed by X-ray diffraction studies.
Spatio-temporal visual properties in the ascending tectofugal system
Authors: Rokszin Alice , Márkus Zita , Braunitzer Gábor , Berényi Antal , Wypych Marek , Waleszczyk Wioletta , Benedek György , Nagy Attila
Published: December 2009

Our study compares the spatio-temporal visual receptive field properties of different subcortical stages of the ascending tectofugal visual system. Extracellular single-cell recordings were performed in the superficial (SCs) and intermediate (SCi) layers of the superior colliculus (SC), the suprageniculate nucleus (Sg) of the posterior thalamus and the caudate nucleus (CN) of halothane-anesthetized cats. Neuronal responses to drifting gratings of various spatial and temporal frequencies were recorded. The neurons of each structure responded optimally to low spatial and high temporal frequencies and displayed narrow spatial and temporal frequency tuning. The detailed statistical analysis revealed that according to its stimulus preferences the SCs has markedly different spatio-temporal properties from the homogeneous group formed by the SCi, Sg and CN. The SCs neurons preferred higher spatial and lower temporal frequencies and had broader spatial tuning than the other structures. In contrast to the SCs the visually active SCi, as well as the Sg and the CN neurons possessed consequently similar spatio-temporal preferences. These data support our hypothesis that the visually active SCi, Sg and CN neurons form a homogeneous neuronal population given a similar spatio-temporal frequency preference and a common function in processing of dynamic visual information.
Synchrotron microanalytical methods in the study of trace and minor elements in apatite
Authors: Rakovan John , Luo Yun , Borkiewicz Olaf
Published: December 2009

Synchrotron microanalytical methods in the study of trace and minor elements in apatite

Synchrotron X-ray facilities have the capability for numerous microanalytical methods with spatial resolutions in the micron to submicron range and sensitivities as low as ppm to ppb. These capabilities are the result of a high X-ray brilliance (many orders of magnitude greater than standard tube and rotating anode sources); a continuous, or white, spectrum through the hard X-ray region; high degrees of X-ray columniation and polarization; and new developments in X-ray focusing methods. The high photon flux and pulsed nature of the source also allow for rapid data collection and high temporal resolution in certain experiments. Of particular interest to geoscientists are X-ray fluorescence microprobes which allow for numerous analytical techniques including X-ray fluorescence (XRF) analysis of trace element concentrations and distributions; X-ray absorption spectroscopy (XAS) for chemical speciation, structural and oxidation state information; X-ray diffraction (XRD) for phase identification; and fluorescence microtomography (CMT) for mapping the internal structure of porous or composite materials as well as elemental distributions (Newville et al. 1999; Sutton et al. 2002; Sutton et al. 2004).

We have employed several synchrotron based microanalytical methods including XRF, microEXAFS (Extended X-ray Absorption Fine Structure), microXANES (X-ray Absorption Near Edge Structure) and CMT for the study of minor and trace elements in apatite (and other minerals). We have also been conducting time resolved X-ray diffraction to study nucleation of and phase transformations among precursor phases in the formation of apatite from solution at earth surface conditions. Summaries of these studies are given to exemplify the capabilities of synchrotron microanalytical techniques.
Whole rock major element influences on monazite growth: examples from igneous and metamorphic rocks in the Menderes Massif, western Turkey
Authors: Catlos Elizabeth , Baker Courteney , Çemen Ibrahim , Ozerdem Cenk
Published: December 2009

Whole rock major element influences on monazite growth: examples from igneous and metamorphic rocks in the Menderes Massif, western Turkey

Monazite (LREEPO4) is a radiogenic, rare-earth bearing mineral commonly used for geochronology. Here we examine the control of major element chemistry in influencing the crystallization of monazite in granites (Salihli and Turgutlu bodies) and garnet-bearing metamorphic assemblages (Bozdag and Bayindir nappes) from the Menderes Massif, western Turkey. In S-type granites from the massif, the presence of monazite correlates to the CaO and Al2O3content of the whole rock. Granites with monazite only are low Ca (0.6-1.8 wt% CaO). As CaO increases (from 2.1-4.6 wt%), allanite [(Ce, Ca, Y)2(Al, Fe3+)3(SiO4)3(OH)] is present. Higher Al2O3(>15 wt%) rocks contain allanite and/or monazite, whereas those with lower Al2O3contain monazite only. However, examining data reported elsewhere for A-type granites, the correlation between major element chemistry and presence of monazite is likely restricted to S-type lithologies. Pelitic schists of the Menderes Massif show no correlation between major element chemistry and presence of monazite. One Bayindir nappe sample contains both prograde garnets and those affected significantly by diffusion. These rocks have likely experienced a complicated multi-stage tectonic history, which influenced their current mineral assemblages. The presence of monazite in a metamorphic rock can be influenced by the number, duration, and nature of events that were experienced and the degree to which fluids were involved. The source of monazite in the Bayindir and Bozdag samples was likely reactions that involved allanite. These reactions may not have significantly changed the bulk composition of the rock.
Primena »Six Sigma« U Kontroli Kvaliteta Zdravstvenih Laboratorija
Authors: Ignjatović Svetlana , Majkić-Singh Nada
Published: December 2009

Primena »Six Sigma« U Kontroli Kvaliteta Zdravstvenih Laboratorija

Cilj svakog postupka ili proizvodnog sistema je dobijanje dobrog proizvoda. Većina metoda kontrole kvaliteta je inicijalno razvijena da pomogne industrijsku proizvodnju. Ovo ne predstavlja iznenađenje s obzirom da masovna proizvodnja tipično zahteva mnogo ponavljanja koje uključuju kontrolisani redosled operacija. Nisu svi prilazi kontroli kvaliteta podjednako efikasni. Neusaglašenosti koje postoje u laboratorijskom određivanju su u osnovi uzrokovane kako prekomernim varijacijama u procesu, tako i greškama. Ključni nedostatak u primeni metoda statističke kontrole kvaliteta ležKi u činjenici da su neefikasne u detekciji i kontroli grešaka, a one danas predstavljaju najdominatniji uzrok neusaglašenosti većine organizacionih procesa. Statističkom kontrolom kvaliteta mogu efikasno da se kontrolišu varijacije u procesu, ali ne mogu da se detektuju ili spreče greške. »Six Sigma« pripada statističkoj kontroli kvaliteta koja pružKa novu metodologiju za merenje karakteristika procesa, a takođe usavršava prethodne metodologije čime dolazi do unapređenja procesa. MenadžKment zasnovan na »Six Sigma« kvalitetu polako ulazi u zdravstvene organizacije pri čemu nudi realnu nadu za unapređenje razmišljanja i procesa menadžKmenta kvaliteta. Jedan od razloga je što se »Six Sigma« fokusira na defekte koji za uzvrat zahtevaju da ciljevi za dobar kvalitet budu definisani. »Six Sigma» pružKa univerzalnu metodologiju kojom se meri kvalitet time što se broje defektni proizvodi, pri čemu se određuje stopa defektnih proizvoda kao »defekti na milion» (»defects per million» ili »DPM»), a koji se zatim konvertuju u »Sigma metriku» uz korišćenje standradnih tabela koje su dostupne u svakom tekstu vezanom za »Six Sigma». »Sigma metrikom» se »Six Sigma» pojednostavljuje i dobija univerzalni »reper» koji govori o karakteristikama procesa. Na ovaj način svi procesi mogu da se okarakterišu na »Sigma skali.« Tipično se vrednosti nalaze između 2 i 6, pri čemu je cilj postizanje »svets- ke klase kvaliteta» koja iznosi 6. Na osnovu podataka koji potiču iz stvarnog sveta zdravstvenih laboratorija očigledno se možKe zaključiti da je izvođenje operacija na današnjim instrumentima dobro. Nova generacija kliničkih analizatora je postigla jako visoku «Sigma metriku«. Korisnici zdravstvene zaštite mogu da užKivaju u novoj eri napretka sa instrumentima i metodama nivoa 6 Sigma ili višim.
Significance of Determining Levels of Apolipoproteins A-I and B in the Diagnostics and Assessment of Lipid-Related Atherogenic Risk in Hyperalpha-Lipoproteinemia, Hypocholesterolemia and Hypo-Hdl-Cholesterolemia
Authors: Kojić-Damjanov Sunčica , đerić Mirjana , Čabarkapa Velibor , Vučurević-Ristić Ljiljana
Published: December 2009

Significance of Determining Levels of Apolipoproteins A-I and B in the Diagnostics and Assessment of Lipid-Related Atherogenic Risk in Hyperalpha-Lipoproteinemia, Hypocholesterolemia and Hypo-Hdl-Cholesterolemia

The significance of determining apolipoproteins apoB and apoA-I and their correlation with lipid status parameters were tested in hyperalpha-lipoproteinemia (30 women), hypocholesterolemia (10 men) and hypo-HDL-cholesterolemia (15 women and 21 men). Control groups were 20 normolipidemic men and women, each. ApoA-I showed positive correlation with HDL-cholesterol in hyperalpha-lipoproteinemia, with total and HDL-cholesterol in hypocholesterolemia, and with total and LDL-cholesterol in females with hypo-HDL-cholesterolemia, and negative correlation with cholesterol ratios only in hypocholesterolemia. ApoB showed a positive correlation with total and LDL-cholesterol in all groups, and with cholesterol ratios in hyperalpha-lipoproteinemia and hypo-HDL-cholesterolemia. The apoB/apoA-I ratio, correlating with the majority of lipid parameters, and with the highest percentage of pathological values in all tested groups, was singled out as the most sensitive parameter for the evaluation of lipid-related atherogenic risks.
The Schemes of External Quality Control in Laboratory Medicine in the Balkans
Authors: Karkalousos Petros
Published: December 2009

The Schemes of External Quality Control in Laboratory Medicine in the Balkans

There are many differences between the national External Quality Control Schemes all around Europe, but the most important ones are certainly those between the countries of the Balkan region. These differences are due to these countries' different political and financial development, as well as to their tradition and the development of clinical chemistry science in each one. Therefore, there are Balkan countries with very developed EQAS and others where there is no such a scheme. Undoubtedly, the scientific community in these countries wants to develop EQAS despite of the financial and other difficulties.
Reading Disabilities in Adults: A Selective Meta-Analysis of the Literature
Authors: Swanson H. Lee , Hsieh Ching-Ju
Published: December 2009

This article synthesizes the experimental literature that compares the academic, cognitive, and behavioral performance of adults with reading disabilities to those of average-achieving adult readers. The central question posed by this review is to what extent and in what manner do adults with reading disabilities differ from adults without reading disabilities on measures assumed to relate to overall reading competence. In all, 52 studies met criteria for a meta-analysis, yielding 776 effect sizes (ESs) with an overall a weighted ES of 0.72 ( SD = 0.54). Moderate to high ESs in favor of adults without reading disabilities emerged on measures of cognition (naming speed [ M = 0.96], phonological processing [ M = 0..87], verbal memory [ M = 0.62]) and achievement (word attack [ M = 1.33], math [ M = 0.75], vocabulary [ M = 0.71], spelling [ M = 1.57], and writing [ M = 0.72]). Hierarchical linear modeling indicated that verbal IQ, vocabulary, math, spelling, and specific cognitive process measures (naming speed, phonological processing, and verbal memory) significantly moderated overall group ES differences. Significantly larger ESs emerged for studies with relatively higher IQ scores when compared to studies with IQ and reading scores in the same low range. Overall, the results support the notion that reading achievement and cognitive deficits in adults with reading disabilities are persistent across age.
College Preparatory Curriculum for All: Academic Consequences of Requiring Algebra and English I for Ninth Graders in Chicago
Authors: Allensworth Elaine , Nomi Takako , Montgomery Nicholas , Lee Valerie E.
Published: December 2009

There is a national movement to universalize the high school curriculum so that all students graduate prepared for college. The present work evaluates a policy in Chicago that ended remedial classes and mandated college preparatory course work for all students. Based on an interrupted time-series cohort design with multiple comparisons, this study found that the policy reduced inequities in ninth grade course work by entering ability, race/ethnicity, and special education status. Although more students completed ninth grade with credits in algebra and English I, failure rates increased, grades slightly declined, test scores did not improve, and students were no more likely to enter college. In sum, few benefits resulted from universalizing college preparatory course work among freshmen, but dropout rates did not increase. Possible explanations are discussed.
Unbiased Causal Inference From an Observational Study: Results of a Within-Study Comparison
Authors: Pohl Steffi , Steiner Peter M. , Eisermann Jens , Soellner Renate , Cook Thomas D.
Published: December 2009

Adjustment methods such as propensity scores and analysis of covariance are often used for estimating treatment effects in nonexperimental data. Shadish, Clark, and Steiner used a within-study comparison to test how well these adjustments work in practice. They randomly assigned participating students to a randomized or nonrandomized experiment. Treatment effects were then estimated in the experiment and compared to the adjusted nonexperimental estimates. Most of the selection bias in the nonexperiment was reduced. The present study replicates the study of Shadish et al. despite some differences in design and in the size and direction of the initial bias. The results show that the selection of covariates matters considerably for bias reduction in nonexperiments but that the choice of analysis matters less.
Teacher Preparation and Student Achievement
Authors: Boyd Donald J. , Grossman Pamela L. , Lankford Hamilton , Loeb Susanna , Wyckoff James
Published: December 2009

There are fierce debates over the best way to prepare teachers. Some argue that easing entry into teaching is necessary to attract strong candidates, whereas others argue that investing in high quality teacher preparation is the most promising approach. Most agree, however, that we lack a strong research basis for understanding how to prepare teachers. This article is one of the first to estimate the effects of features of teachers’ preparation on teachers’ value added to student test score performance. Our results indicate variation across preparation programs in the average effectiveness of the teachers they are supplying to New York City schools. In particular, preparation directly linked to practice appears to benefit teachers in their 1st year.
The clinical significance and optimal timing of postoperative computed tomography following cranial surgery
Authors: Khaldi Ahmad , Prabhu Vikram C. , Anderson Douglas E. , Origitano Thomas C.
Published: December 2009

Object

This study was conducted to evaluate the value of postoperative CT scans in determining the probability of return to the operating room (OR) and the optimal time to obtain such scans to determine the effects of surgery.

Methods

Between January and December 2006 (12 months), all postoperative head CT scans obtained for 3 individual surgeons were reviewed. Scans were divided into 3 groups, which were determined by the preference of each surgeon: Group A (early scans—scheduled between 0 and 7 hours); Group B (delayed scans—scheduled between 8 and 24 hours); and Group C (urgent scans—ordered because of a new neurological deficit). The initial scans were reviewed and analyzed in 2 different fashions. The first was to analyze the efficacy of the scans in predicting return to the OR. The second was to determine the optimal time for obtaining a scan. The second analysis was a review of serial postoperative scans for expected versus unexpected findings and changes in the acuity of these findings over time.

Results

In 251 (74%) of 338 cases, the patients had postoperative head CT scans within 24 hours of surgery. Analysis 1 determined the percent of patients returning to the OR for emergency treatment based on postoperative scans: Group A (early)—133 patients, with 0% returning to the OR; Group B (delayed)—108 patients, with 0% returning to the OR; and Group C (urgent)—10 patients, with 30% returning to the OR (p < 0.05). Analysis 2 determined the optimal timing of postoperative scans and changes in scan acuity: Group A (early scan) had an 11% incidence of change in acuity on subsequent scans. Group B (delayed scan) had a 3% incidence of change in acuity on follow-up scans (p < 0.05).

Conclusions

Routine postoperative scans at 0–7 hours or at 8–24 hours are not predictive of return to the OR, whereas patients with a new neurological deficit in the postoperative period have a 30% chance of emergency reoperation based on CT scans. In addition, early postoperative scans (0–7 hours) fail to predict CT changes, which might evolve over time and may influence postoperative medical management.
Cushing's lost cases of “radium bomb” brachytherapy for gliomas
Authors: Seymour Zachary A. , Cohen-Gadol Aaron A.
Published: December 2009

Although recent efforts to advance the treatment of gliomas through radiotherapy and chemotherapy may seem to be a relatively new area of growth and development, these efforts have been in progress since the therapeutic potential of radiation therapy was discovered in the late 19th century. Cushing's use of brachytherapy has been mentioned several times in the literature without receiving an appropriate in-depth analysis. The reasoning behind Cushing's initial use of brachytherapy was not fully examined, and a close analysis of the outcomes of this therapy was not made. In addition, Cushing's use of his “radium bomb” occurred more commonly than the 3 cases previously documented. The authors reviewed all the patient records available at the Cushing Brain Tumor Registry—which represents the most complete series of patient records from the Cushing era—and selected those patients who underwent treatment with Cushing's “radium bomb.” The authors place these early attempts to optimize interstitial radiation of brain tumors in their historical perspective.
Binding of Natural and Synthetic Polyphenols to Human Dihydrofolate Reductase
Authors: Sánchez-del-Campo Luís , Sáez-Ayala Magalí , Chazarra Soledad , Cabezas-Herrera Juan , Rodríguez-López José Neptuno
Published: December 2009

Dihydrofolate reductase (DHFR) is the subject of intensive investigation since it appears to be the primary target enzyme for antifolate drugs. Fluorescence quenching experiments show that the ester bond-containing tea polyphenols (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin gallate (ECG) are potent inhibitors of DHFR with dissociation constants (KD) of 0.9 and 1.8 μM, respectively, while polyphenols lacking the ester bound gallate moiety [e.g., (-)-epigallocatechin (EGC) and (-)-epicatechin (EC)] did not bind to this enzyme. To avoid stability and bioavailability problems associated with tea catechins we synthesized a methylated derivative of ECG (3-O-(3,4,5-trimethoxybenzoyl)-(-)-epicatechin; TMECG), which effectively binds to DHFR (KD = 2.1 μM). In alkaline solution, TMECG generates a stable quinone methide product that strongly binds to the enzyme with a KD of 8.2 nM. Quercetin glucuronides also bind to DHFR but its effective binding was highly dependent of the sugar residue, with quercetin-3-xyloside being the stronger inhibitor of the enzyme with a KD of 0.6 μM. The finding that natural polyphenols are good inhibitors of human DHFR could explain the epidemiological data on their prophylactic effects for certain forms of cancer and open a possibility for the use of natural and synthetic polyphenols in cancer chemotherapy.
Isolation of C11 Cyclopentenones from Two Didemnid Species, Lissoclinum sp. and Diplosoma sp.
Authors: Ogi Takayuki , Margiastuti Palupi , Teruya Toshiaki , Taira Junsei , Suenaga Kiyotake , Ueda Katsuhiro
Published: December 2009

A series of new C11 cyclopentenones 1-7 was isolated, together with four known metabolites 9/10, 12 and 13, from the extract of the didemnid ascidian Lissoclinum sp. The other didemnid ascidian Diplosoma sp. contained didemnenones 1, 2 and 5, and five known metabolites 8-12. The structures of 1-7 were elucidated by spectroscopic analyses. Cytotoxicity of the isolated compounds was evaluated against three human cancer cell lines (HCT116, A431 and A549).
The Soluble Epoxide Hydrolase Inhibitor AR9281 Decreases Blood Pressure, Ameliorates Renal Injury and Improves Vascular Function in Hypertension
Authors: Imig John D. , Carpenter Margaret A. , Shaw Sean
Published: December 2009

Soluble epoxide hydrolase inhibitors (sEHIs) are demonstrating promise as potential pharmaceutical agents for the treatment of cardiovascular disease, diabetes, inflammation, and kidney disease. The present study determined the ability of a first-inclass sEHI, AR9281, to decrease blood pressure, improve vascular function, and decrease renal inflammation and injury in angiotensin hypertension. Rats were infused with angiotensin and AR9281 was given orally during the 14-day infusion period. Systolic blood pressure averaged 180 ± 5 mmHg in vehicle treated and AR9281 treatment significantly lowered blood pressure to 142 ± 7 mmHg in angiotensin hypertension. Histological analysis demonstrated decreased injury to the juxtamedullary glomeruli. Renal expression of inflammatory genes was increased in angiotensin hypertension and two weeks of AR9281 treatment decreased this index of renal inflammation. Vascular function in angiotensin hypertension was also improved by AR9281 treatment. Decreased afferent arteriolar and mesenteric resistance endothelial dependent dilator responses were ameliorated by AR9281 treatment of angiotensin hypertensive rats. These data demonstrate that the first-in-class sEHI, AR9281, lowers blood pressure, improves vascular function and reduces renal damage in angiotensin hypertension.
Sonar Sensor Models and Their Application to Mobile Robot Localization
Authors: Burguera Antoni , González Yolanda , Oliver Gabriel
Published: December 2009

This paper presents a novel approach to mobile robot localization using sonar sensors. This approach is based on the use of particle filters. Each particle is augmented with local environment information which is updated during the mission execution. An experimental characterization of the sonar sensors used is provided in the paper. A probabilistic measurement model that takes into account the sonar uncertainties is defined according to the experimental characterization. The experimental results quantitatively evaluate the presented approach and provide a comparison with other localization strategies based on both the sonar and the laser. Some qualitative results are also provided for visual inspection.
Satellite RNAs and Satellite Viruses of Plants
Authors: Hu Chung-Chi , Hsu Yau-Heiu , Lin Na-Sheng
Published: December 2009

The view that satellite RNAs (satRNAs) and satellite viruses are purely molecular parasites of their cognate helper viruses has changed. The molecular mechanisms underlying the synergistic and/or antagonistic interactions among satRNAs/satellite viruses, helper viruses, and host plants are beginning to be comprehended. This review aims to summarize the recent achievements in basic and practical research, with special emphasis on the involvement of RNA silencing mechanisms in the pathogenicity, population dynamics, and, possibly, the origin(s) of these subviral agents. With further research following current trends, the comprehensive understanding of satRNAs and satellite viruses could lead to new insights into the trilateral interactions among host plants, viruses, and satellites.
Active and relict alluvial fans on contact karst of the Vrhpoljska brda hills, Slovenia
Authors: Stepišnik Uroš
Published: December 2009

Several types of contact karst are found within the Slovenian karst, but the most common is the ponor type, which usually develops at boundaries between flysch and limestone. One of these types is in the area of Vrhpoljska brda. In this contact karst area two types of alluvial fans appear on carbonate bedrock. Members of the first type are ordinary alluvial fans with active alluvial processes where flysch derived sediment covered limestone surface in a distinct fan shape. The other type, described as relict alluvial fans, is fan-shaped features preserved in the carbonate bedrock. These essentially bedrock landforms developed as a result of the gradual removal of pre-existing alluvial fan cover and the concurrent but non-uniform chemical denudation of the underlying carbonate bedrock. Geomorphologic and morphometric description of alluvial fans and relict alluvial are provided in the article and mechanisms of relict alluvial fans formation and transformation are discussed.
Erosion processes in Slovene Istria – part 2: Badlands
Authors: Zorn Matija
Published: December 2009

This article is a continuation of the article on soil erosion in submediterranean Slovene Istria from the first issue of the 2009 (49-1) journal. In this article we present geomorphic processes in the badlands of the same area (Dragonja River basin, SW Slovenia): sediment production from steep bare (Eocene) flysch slopes (rockwall retreat), movements of flysch debris along erosion gullies, and geomorphic processes on talus slopes. Sediment production of flysch rocks was determined by measurements on erosion plots and totals around 80 kg/m2 per year on average, which means that steep bare flysch rockwalls retreat at a speed of 35 to 50 mm per year.The badlands not only contain flysch walls but also slopes already eroded by erosion rills and gullies. A dam in one of the erosion gullies with the catchment area of 0.1 ha captured 20 tons of debris in fourteen months.Monitoring on talus slopes of the badlands revealed their dual character because erosion here alternates with accumulation.