bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of Orvosi Hetilap in the development of contemporary Hungarian gastroenterology. Part 4: 1989–2008
Authors: Buzás György Miklós
Published: April 2009

Az
Orvosi Hetilap
1948 és 1989 között az előző időszakhoz képest jelentősen több gasztroenterológiai tárgyú publikációt közölt. Az ismeretek elsősorban angol közvetítéssel kerültek a magyar szakirodalomba.
Célkitűzés:
Az
Orvosi Hetilap
ban 1989 és 2008 között megjelent gasztroenterológiai tárgyú publikációk kiértékelése.
Módszer:
A szerző manuális módszerrel áttekintette a folyóirat 1989 és 2008 közötti évfolyamait. A gasztroenterológiai tárgyú eredeti közleményeket, lapszemléket és könyvismertetéseket azonosította és azokból adatbázist készített. A publikációkat tematikai csoportokba sorolta és arányukat meghatározta. Az eredményeket összehasonlította az 1948 és 1989 közötti időszak publikációs tevékenységével. Részletesen áttekintette a laparoszkópos sebészet, a májátültetés és a genetikai ismeretek recepcióját az
Orvosi Hetilap
ban. Eredmények: 1989 és 2008 között az
Orvosi Hetilap
ban 2817 gasztroenterológiai tárgyú dolgozat jelent meg (1067 eredeti közlemény, 1698 folyóirat-referátum, 52 könyvismertetés), ez az összes közlemény 10,1%-a. Az előző korszakhoz képest a gasztroenterológiai tárgyú közlemények száma nem változott (p = 0,82), a folyóirat-referátumok (p = 0,006) és könyvismertetések száma jelentősen csökkent (p = 0,01). 2007-től megjelent az
Orvosi Hetilap
online változata és a
Hungarian Medical Journal
. A 1989 és 2008 között legtöbbet a máj (17,8%) és epeutak betegségeivel (4,31%), ezen belül a vírusos hepatitisekkel foglalkoztak (7,0%). Laparoszkópos sebészettel 27 (1,8%), májátültetéssel 39 (2,6%), genetikával 61 (4,0%) közlemény foglalkozott. Százharmincegy szakfolyóiratot szemléztek, a gasztroenterológiai tárgyú folyóirat-referátumok száma az előző időszakhoz képest csökkent (p = 0,006). A referátumok 65,4%-a magfolyóiratokban jelent meg. Az angol nyelvű lapok aránya 62,4%, a lapszemlék 31,5%-a német, 1,69%-a francia forrásból táplálkozik, tehát az angol dominancia erősödött. A könyvismertetések száma 211-ről 52-re csökkent (p = 0,01). A laparoszkópos sebészetben elsősorban a cholecystectomiával szerzett tapasztalatokat ismertették. A májátültetés kérdéskörének fő fóruma az
Orvosi Hetilap
volt. A 2000-es években az egyetemi centrumokban működő munkacsoportok ismertették az emésztőszervi betegségek genetikai kutatásait.
Következtetés:
Az utóbbi két évtizedben az
Orvosi Hetilap
sikerrel látta el hagyományos feladatát a hazai orvosok szakmai tájékoztatásában, emellett fontos szerepet vállalt a kortárs gasztroenterológia új vívmányainak (laparoszkópos sebészet, májátültetés, genetika) ismertetésében.
Transformation of chronic lymphocytic leukemia to myelodysplastic syndrome: case presentation and review of the literature
Authors: Telek Béla , Pfliegler György , Reményi Gyula , Méhes Leonóra , Batár Péter , Udvardy Miklós
Published: April 2009

A krónikus lymphoid leukaemia (CLL) növeli a különböző szolid tumorok kialakulásának veszélyét, transzformálódhat egyéb lymphoid eredetű malignus betegségbe, myeloid jellegű malignus kórkép azonban ritkán társul CLL-hez. A szerzők egy kezeletlen CLL-es betegük kórtörténetét ismertetik, akiben hat évvel a CLL felismerését követően myelodysplasticus szindróma [refrakter anaemia gyűrűs („ringed”) sideroblastokkal] alakult ki. A myelodysplasticus szindróma kialakulásával és progressziójával a CLL háttérbe szorulását észlelték. A kórtörténet és irodalom ismertetése mellett áttekintik a CLL-hez társuló malignus myeloid betegségek patogenezisének lehetőségeit.
Disorders of perioperative heat balance and their treatments
Authors: Fazekas Brigitta , Simon Éva , Fülesdi Béla
Published: April 2009

Az intraoperatív hypothermia felismerésének és a maghőmérséklet-csökkenés megelőzésének jelentősége az utóbbi 10 évben tisztázódott részleteiben. Igazolódott, hogy a maghőmérséklet a hosszabb időtartamú műtétek esetén 1–3 °C-kal csökken. Ugyanakkor már enyhe hypothermia is (36 °C alatti maghőmérséklet) számos, a betegség kimenetelét hátrányosan befolyásoló szövődménnyel bírhat, úgymint perioperatív cardialis szövődmények, fokozott vérzékenység, a transzfúziós igény megnövekedése, a sebgyógyulás ütemének lassulása, a gyógyszerek metabolizmusának csökkenése. Igazolódott az is, hogy az intraoperatív hypothermia következményeinek kezelése mintegy megduplázza a betegek kezelési költségeit. Ezért indokoltnak tartjuk, hogy összefoglaljuk az intraoperatív hypothermia létrejöttével, következményeivel és megelőzésével kapcsolatos legkorszerűbb ismereteket.
Chlamydia trachomatis infections in neonates – overview of current laboratory diagnostics
Authors: Balla Eszter
Published: April 2009

A közelmúltban publikált szakirodalom és saját laboratóriumi tapasztalatai alapján a szerző összegzi a klinikai tüneteket, a diagnosztikus lehetőségeket és a megelőzés eszközeit azokban a neonatalisChlamydia trachomatis-fertőzésekben, ahol felmerül e kórokozó potenciális vagy igazolt etiológiai szerepe. A gyakran tünetmentes, fel nem ismert anyai fertőzés megnehezíti a definitív diagnózist, amelyhez a megfelelő mintavétel és a célzott szűrés elengedhetetlen. A neonatalisChlamydia trachomatis-fertőzések incidenciájával kapcsolatban csak becsült adataink vannak, holott rendelkezünk olyan laboratóriumi tesztekkel, amelyekkel diagnosztizálhatjuk az érintett újszülötteket, akiknél a korai kezelésnek köszönhetően általában csak enyhe-mérsékelt formában jelentkezik a fertőzés. Célzott szűrési stratégiát kellene megvalósítani annak érdekében, hogy csökkenjen a fertőzött terhesek száma, és ezáltal mérséklődjön a vertikális transzmisszió lehetősége.
Extracellular calcium sensing under normal and pathological conditions
Authors: Tőke Judit , Patócs Attila , Gergics Péter , Bertalan Rita , Tóth Miklós , Rácz Károly , Tulassay Zsolt
Published: April 2009

Régóta ismert, hogy az ionos kalcium fontos sejten belüli másodlagos hírvivő szerepet tölt be. Az utóbbi 15 évben megismert kísérletes vizsgálatok és klinikai tanulmányok eredményei alapján az is egyértelművé vált, hogy az ionos kalcium elsődleges jelként is működik: az extracelluláris kalciumion egy G-fehérjéhez kapcsolódó sejtfelszíni receptort aktivál, amit kalciumérzékelő receptornak neveztek el. A szerzők összefoglalják a kalciumérzékelő receptor szerepét a kalciumhomeosztázis fenntartásában, ismertetik a receptor működésének szövetspecifikus sajátosságait és azokat a kórképeket, amelyek a kalciumérzékelés zavarával járnak. A kalciumérzékelő receptor génjének funkcióvesztést vagy fokozott működést okozó csírasejtes mutációi hyper- vagy hypocalcaemiával járó öröklődő betegségeket váltanak ki. Az inaktiváló hatású mutációk heterozigóta formában familiáris hypocalciuriás hypercalcaemiát, míg homozigóta formában a gyakran életet veszélyeztető újszülöttkori hyperparathyreosist okozzák. Az autoszomális domináns hypocalcaemia hátterében aktiváló mutációk állnak. A szerzők összefoglalják ezeknek a betegségeknek a klinikai és laboratóriumi jellemzőit és a kezelés lehetőségeit. Áttekintik azokat a molekuláris folyamatokat, amelyek primer és szekunder hyperparathyreosisos betegekben hibás kalciumérzékelést váltanak ki, valamint azokat a klinikai vizsgálatokat, amelyek a kalciumérzékelő receptorgén genetikai variációinak funkcionális következményeiről számolnak be.
Analytical problems in determination of hemoglobin A 1c and the different ways of its interpretation
Authors: Góth László
Published: April 2009

A glikált proteinek a glükóz és a fehérjék aminosava között lejátszódó nem enzimatikus reakció termékei. A hemoglobin-A
1c
a glükóz és a hemoglobin mindkét béta-láncának N-terminális valinja közötti reakció eredményeként képződik, és a koncentrációja a vörösvértestek életidejének és a vér glükózkoncentrációjának függvénye. Az utóbbinak tulajdoníthatóan az előző 6–8 hét integráltglükóz-koncentrációját jelzi. A HbA
1c
-t a glykaemia hosszabb távú monitorozására alkalmas, valamint a diabetes komplikációinak kockázati tényezőjeként is szolgál. A HbA
1c
-mérési eredmény az előzőkön túlmenően függ még a vér egyéb szénhidrátjaitól és más alkotóitól, a meghatározási módszertől, illetve annak kalibrálási módjától. Nemzetközi társaságok (IFCC, ADA) dolgoztak ki ajánlásokat (NGSP, DDCT, IFCC) a HbA
1c
-meghatározás standardizálására. Az eredmény megadására javasolja az NGSP a százalékot (g HbA
1c
/g hemoglobin) és az IFCC az SI egységet (mmol HbA
1c
/mol HbA). Több közleményben található olyan statisztikai módszerrel meghatározott egyenlet, amelynek segítségével a HbA
1c
-ből az előző 6–8 hét átlagos glükózkoncentrációja (eADAG) megbecsülhető. Az eljárás klinikai relevanciáját több szerző még nem látja teljesen megalapozottnak.
Molecular mechanisms of insulin resistance in obesity and type 2 diabetes mellitus
Authors: Winkler Gábor , Cseh Károly
Published: April 2009

A zsírszövetben az inzulinreceptor jelátviteli folyamatait auto-, para- és endokrin hatásokkal szabályozó számos fehérje termelődik és szekretálódik. Ezek közül több, így a tumornekrózis-faktor-α és szolúbilis receptor formái, az sTNFR1 és sTNFR2, a rezisztin, retinolkötő fehérje-4, plazminogénaktivátor-inhibitor, lipokain-1 gátolja az inzulin jelátviteli folyamatait és inzulinrezisztenciát okoz, elsősorban a zsírszövetben, a májban, az izomszövetben, az agyban, az endothelsejtekben, valamint a hasnyálmirigy β-sejtjeiben. Más fehérjék, így az adiponektin, visfatin, vaspin, omentin, apelin és chemerin pedig javítják az inzulinreceptor jelátvitelét. Az összefoglalás áttekinti az inzulinreceptor jelátviteli folyamatainak főbb részleteit és kitér az elhízásban, valamint a 2-es típusú cukorbetegségben észlelhető inzulin- és citokinrezisztenciák patomechanizmusában a közelmúltban megismert molekuláris tényezőkre (például a suppressor of cytokine signaling fehérje család).
Preoperative revascularization in high-risk patients undergoing vascular surgery
Authors: Rácz Kristóf , Tiszai-Szűcs Tamás , Gál János , Kertai Miklós D.
Published: April 2009

Helyreigazítás a
DOI: 10.1556/OH.2009.28545
közleményhez. (OH 150. évfolyam, 8. szám – 2009. február 22. 341–352. o.)
Forensic landslide investigations in Hong Kong
Authors: Ho Ken , Lau Tony , Lau Jonathan
Published: April 2009

Serious landslides have occurred in Hong Kong from time to time with loss of life and significant socio-economic impact on the community. The systematic landslide investigation programme implemented by the Hong Kong government's geotechnical engineering office has proved to be an important asset-management tool in contributing to enhanced landslide-risk management and professional practice. This paper reviews the evolution of forensic landslide investigations in Hong Kong and presents the framework of the systematic landslide investigation programme, together with the key lessons learnt.
Durability of rock-filled-dam face-slab concrete
Authors: Woo S.-K. , Song Y.-C. , Won J.-P.
Published: April 2009

The present study examined the durability of face-slab concrete in concrete-faced rock-filled dams. The durability of face-slab concrete can be improved by optimising the amount of fly ash in the cement mixture. Durability tests, including permeability, abrasion resistance, repeated wetting and drying and repeated freezing and thawing, were conducted for face-slab concrete using different amounts of fly ash and polypropylene fibre. When the effect of the fly ash content on the concrete durability was evaluated, the results showed that a 20% fly ash content yielded an optimum durability level for concrete-faced rock-filled dams
Fuzzy logic approach for estimating durability of concrete
Authors: Nehdi M. L. , Bassuoni M. T.
Published: April 2009

In this work, it is shown how fuzzy inference systems can be constructed to produce a global durability evaluation factor for concrete based on various performance criteria from accelerated tests. This can facilitate the decision-making process during the design stage by identifying optimum concrete mixtures proposed for specified field exposure. A fuzzy inference system was built for the specific case of various self-consolidating concrete mixtures subjected to ammonium sulfate attack. The performance of this model was compared with that of other models that enable decision making: the remaining service life model and compromise programming. Results of the fuzzy inference system had a better correlation with compromise programming (R2 = 0·7) than that with the remaining service life model (R2 = 0·5), and better represented the actual degradation observed in test specimens. It is shown that the proposed fuzzy inference model is rational, clear, reliable, versatile and flexible since it can be easily updated with new data or modified to accommodate future findings.
Sociodemographic, Sexual, and HIV and Other Sexually Transmitted Disease Risk Profiles of Nonhomosexual-Identified Men Who Have Sex With Men
Authors: Jeffries William L.
Published: April 2009

I examined sociodemographic, sexual, and HIV and other sexually transmitted disease risk differences among homosexual- and nonhomosexual-identified men who have sex with men (MSM) in the United States. Non-Mexican Latino ethnicity, marriage or cohabitation, religiosity, and incarceration history were positively associated with being nonhomosexual identified. Being nonhomosexual identified was associated with some risk (e.g., more sexual intercourse while intoxicated) and protective (e.g., fewer male partners) behaviors. Probabilistic sampling strategies may be useful in future research and intervention efforts.
Mobilizing a Medical Home to Improve HIV Care for the Homeless in Washington, DC
Authors: Wright Maurice Alexander , Knopf Amelia Shaw
Published: April 2009

African Americans face a higher burden of HIV infection, morbidity, and mortality than other ethnic groups in the United States. As an organization that exists to serve the homeless and impoverished of Washington, DC, So Others Might Eat (SOME) works diligently to address this disparity. SOME's clients are primarily African Americans who often face obstacles to HIV care because of low socioeconomic status, mistrust of the medical establishment, and fear of being identified as HIV positive. We relate the lessons we learned at SOME's medical clinic while trying to better address the needs of our clients living with HIV/AIDS. Chief among those lessons was the need to shift from considering our patients “noncompliant” with their HIV-related care to recognizing they had needs we were not addressing.
Are HIV/AIDS Prevention Interventions for Heterosexually Active Men in the United States Gender-Specific?
Authors: Dworkin Shari L. , Fullilove Robert E. , Peacock Dean
Published: April 2009

Although gender-specific theories are often deployed in interventions to reduce women's HIV risks, the same is often not true for interventions among men. Theories of masculinity are not guiding most US research on the risky sexual behavior of heterosexual men or on what can be done to intervene.

We first assess the extent to which evidence-based HIV-prevention interventions among heterosexually active men in the United States draw upon relevant theories of masculinity. Next, we introduce a useful framework within masculinity and gender studies that can be applied to HIV-prevention interventions with heterosexually active men.

Finally, we make suggestions to improve the gender specificity of HIV-prevention interventions for heterosexually active men in the United States.
Far-Field Volumetric Distribution of Fracturing Fluids away from an Uncemented Horizontal Liner in the Bakken Formation
Authors: Dunek Kenneth L. , Walser Doug W. , Astakhov Dmitriy K.
Published: April 2009

The Middle Bakken member of the Bakken series in the Williston Basin is sometimes completed with horizontal open holes, or with horizontal uncemented liners. Completion strategy involves fracture stimulation of the mature Upper and Lower Bakken Shales above and below the middle Bakken member (often a thin, moderately low porosity carbonate or siltstone). Knowledge of the volumetric fluid distribution away from the wellbore in the middle Bakken member is important, in terms of determining which portions of the reservoir are actually stimulated.

A case study of a Williston Basin Bakken completion in which precision surface tiltmeter technology mapped volumetric fracture distribution along an uncemented horizontal liner is presented.

When a long horizontal interval with unknown initiation points is stimulated, the number of created hydraulic fractures is unknown, as well as fracture orientation and dimensions. There are often more degrees of freedom than the number of measurements, and the same surface deformation response may be simulated by different combinations of fractures of various orientation and sizes. To reduce the number of unknown parameters, the wellbore may be divided into several segments, with all fracture volume in each segment placed in the middle, and the size of each segment larger than the spatial resolution of the tiltmeter array.
Non-Darcy Porous Media Flow According to the Barree and Conway Model: Laboratory and Numerical Modeling Studies
Authors: Lai Bitao , Miskimins Jennifer L. , Wu Yu-Shu
Published: April 2009

This paper presents supplementary laboratory data to show that a non-Darcy flow model, proposed by Barree and Conway in 2004, is capable of overcoming the limitation with the Forchheimer non-Darcy equation in high flow rates while describing the entire range of relationships between rate and potential gradient from low- to high-flow rates through proppant packs using a single equation or model. To supplement these laboratory findings, a numerical model is developed that incorporates the Barree and Conway model into a general-purpose reservoir simulator for modeling single-phase non-Darcy flow in porous and fractured media. In the numerical approach, flow through fractured rock is handled using a general multi-continuum approach, applicable to both continuum and discrete fracture conceptual models. The numerical formulation is based on a discretization using an unstructured grid of regular or irregular meshes, followed by time discretization carried out with a backward, first-order, finite-difference method. The final discrete nonlinear equations are handled fully implicitly, using Newton iteration. Additionally, an analytical solution under steady-state linear flow condition is derived and used to verify numerical simulation results for the steady-state linear flow case. The numerical model is applied to evaluate the transient flow behavior at an injection well for non-Darcy flow according to the Barree and Conway model. Results show that the parameter of characteristic length, τ, is more sensitive than other parameters; while the impact of the minimum permeability plateau is shown only at extremely large flow rates or pressure gradients. The proposed numerical modeling approach is suitable for modeling various types of multi-dimensional non-Darcy flow through porous and fractured heterogeneous reservoirs.
From Hydraulic Fracturing, What Can We Learn About Reservoir Properties of Tight Sand at the Wattenberg Field in the Denver-Julesburg Basin?
Authors: Yang Yuanhai , Birmingham Thomas , Kremer Anne
Published: April 2009

While hydraulic fracturing is the most commonly used stimulation method for the Codell tight sand at the Wattenberg Field, the authors have observed that the leak-off tests during a typical frac can be utilized to calculate the near wellbore reservoir pressure, far-field reservoir pressure, and permeability indicator. The correlations calculating the reservoir pressures are based on the linear relationship between the fracture closure pressure and reservoir pressure, whereas the permeability indicator is inferred from an analysis of the leak-off coefficiency, or a critical factor of the formation transmissibility. The validity of these methods has been substantiated by the corresponding pertrophysical property distribution, as well as well performances. As the results of these methods, the distribution of the calculated reservoir pressures and permeability indicator have greatly benefited the infill drilling program in terms of situating new in high pressure and high permeability areas while avoiding depleted places.
Reservoir Simulation Study of An In-situ Conversion Pilot of Green-River Oil Shale
Authors: Shen Chonghui
Published: April 2009

Shell Oil Company conducted an oil shale thermal conduction pilot in the Piceance Basin of Colorado during 1997 and 1998. Six heaters and one producer were arranged in a single unconfined hexagonal seven spot pattern to test the viability of the Shell's proprietary in-situ conversion process (ICP) in oil shale under field conditions and to substantiate the in-house experiments that produced high quality crude. The pilot succeeded in meeting all of the intended objectives. The history match of the production data, however, encountered some technical challenges and hindered the full interpretation of test results.

This paper presents the results and findings of a new history match study of the pilot. This simulation succeeded in achieving a good match of the production data by the identification of (1) borehole reflux heat loss, and (2) production impairment from scale build-up and the proper adjustment of well skin effects in the model. It also confirmed that the ICP performance observed in laboratory could be used as a good proxy for ICP in field.
Micro-Emulsion Effectiveness for Twenty Four Wells, Eastern Green River, Wyoming
Authors: Crafton J. W. , Penny G. S. , Borowski D. M.
Published: April 2009

The evaluation of 24 wells representing 339 stages of fracture stimulation which produce from the Lance interval in the northeastern Pinedale Anticline area of the Green River Basin, Wyoming has been conducted to determine if the use of a micro-emulsion (ME) surfactant intended to reduce permeability impairment and improve load recovery, had any observable benefits. The well group consisted of wells in a limited contiguous six square mile area, with 10 wells having 1.5 gallons of ME per thousand used throughout the fracture stimulations, but at no other time during in-well operations. Fourteen wells completed approximately nine months earlier had no micro-emulsion used during stimulation or other in-well operations. Based on the matched reservoir properties and effective degree of stimulation, 20 year forecasts were performed for each well. Then comparisons of those results and various treating parameters were used to assess the potential benefit arising from using ME. The determination of potential benefit was assessed using classical statistical methods to ensure that the interpretation was as unbiased as possible. From that analysis, there is distinct and clear benefit from using the micro-emulsion to facilitate placing the fracture stimulations, to increase effective fracture length, to minimize damage arising from operational shut-ins and especially to increase gas recovery and net present value of wells in which the micro-emulsion system is used.
A Simple Methodology for Direct Estimation of Gas-in-Place and Reserves Using Rate-Time Data
Authors: Johnson N. L. , Currie S. M. , Ilk D. , Blasingame T. A.
Published: April 2009

Estimation of contacted gas-in-place/reserves in unconventional (low/ultra-low permeability) gas reservoirs is a problematic issue, and the uncertainty associated with the estimate is relatively higher. In this work we provide a robust methodology for estimating gas reserves in tight gas/shale gas systems based (primarily) on the use of an integrated approach which makes use of the following models: Semi-analytical formulation — "Quadratic" rate-cumulative relation type curve (Blasingame and Rushing [2005]).Empirical formulation — "power-law exponential" rate decline model (Ilk et al [2008a] and [2008b]).

A dimensionless quadratic rate-cumulative type curve is derived using the rate-cumulative relation proposed by Blasingame and Rushing (2005) and is given by: qD=1−αGpD+α2GpD2(where qD=qg/qgi,GpD=Gp/G,and  α=G/(qgi/Di)by definition)

A "reverse solution" for the α-parameter enables the analyst to establish the existence of boundary-dominated flow — directly from the data. Our experience using synthetic and field data suggests that, for the Blasingame and Rushing model, the α-parameter is equal to two (2) for full boundary-dominated flow.

We have also written the "power-law exponential rate decline relation" in dimensionless rate-time form and we employ the type-curve procedures for the analysis of a given set of rate-time data. The dimensionless power-law exponential rate decline relation is given as: qDd=exp[−D˜∞tDd−tDdn]

We have validated our analysis procedure for this model using a two numerical gas simulation cases and we have applied this procedure to several tight gas and shale gas cases. Our results show that when gas production data are analyzed using the integrated approach described in this work then the uncertainty in reserves estimates is reduced. Specifically, expressing the rate-cumulative production data functions in dimensionless forms provides a direct diagnostic of the boundary-dominated flow regime. Power law exponential rate decline type curves help the analyst to identify the features (character) in the rate data.
Calibrated Log Model and Reservoir Understanding Allows Accurate Prediction of Production and Improved Hydraulic-Fracturing Designs
Authors: Garcia Mariano , Mullen Michael J. , James Aaron
Published: April 2009

The Frontier formation in the Moxa Arch (Wyoming) is a complex, tight sandstone reservoir. As with any other tight formations, hydraulic-fracture stimulation is required to unlock the hydrocarbon reserves. This reservoir is also known for having high water and condensate production that seriously diminish the gas production, despite good reservoir quality, and can cause confusion when comparing the effectiveness of different stimulation techniques. A good understanding of reservoir characterization and production analysis is critical when comparing the effectiveness of different stimulation treatments across the field. This work addresses these topics by applying a systematic loop process that begins with reservoir evaluation, followed by completion design and production history analysis to identify the optimal treatment for each area in the field. The measure of success in this model was the accurate prediction of production using a reservoir flow-capacity model based on the parameters obtained from a calibrated log model specific to this reservoir and year-over-year production improvement. Once production capacity of the reservoir was known, an analysis allowed completion designs to be ranked by efficiency, from best to worst. Production-history matching provided additional information for a better understanding of the reservoir, as well as some other completion efficiencies. The results of this analysis were the key to identify necessary changes to improve fracture designs.

In this study, fifty one (51) wells that were completed before 2006 were used to generate the model to predict production. The model was later successfully tested using fourteen wells completed in 2007, where actual production matched model predictions and showed improvement over similar offset completions.

Different hydraulic-fracture treatment-design criteria were presented as a result of this study as optimized designs based on return on investment (ROI) for the Frontier formation. Each design criteria corresponds to specific areas of the field, where very clear and different fluid/gas ratios were identified.
Paradigm Change: Proppant Fracture Treatments in the Lower Green River Formation of the Altamont-Bluebell Field, Utah
Authors: Rajappa Bharath , Brown Devin L. , Lytle Denise M.
Published: April 2009

The Altamont-Bluebell field produces oil and gas from fractured, tight, lacustrine deposits. Initial field discovery is dated back to 1950. The main producing intervals are the Wasatch and the lower portion of the Green River formation. The lower Green River intervals are found at a depth of 8,000-10,500 feet and are the focus of this study.

Previous stimulation in the lower Green River formation mainly consisted of acid breakdown treatments. With the advent of better fracturing fluid additives and proppants, hydraulic fracturing has shown to be more effective when compared to acid stimulation treatments.

This work compares production data from over 20 hydraulically fractured recompletions done in the lower Green River formation. Fracture modeling with a fully functional 3D simulator is also presented to gain better insight into the fracture design. Finally, we present pitfalls and techniques to better stimulate the tight formations encountered.
Causes and distribution of arsenic contamination in Bangladesh: evidence from the literature
Authors: Nahar N.
Published: April 2009

In attempting to eliminate disease caused by drinking polluted surface water, millions of tube-wells were drilled in Bangladesh. However, owing to arsenic in groundwater, the availability of safe drinking water has declined from earlier achievement of 97% to 51.2%. This article reviews the causes and distribution of arsenic concentration in rural Bangladesh from a wide variety of literature. Scientists have converged to two hypotheses for causes of arsenic in groundwater: the pyrite oxidation hypothesis and the oxy-hydroxide reduction hypothesis. There is a positive correlation between arsenic content in irrigated groundwater and arsenic contained in soils. There is a significant presence of arsenic in rice and leafy vegetables. Today, arsenic is causing toxicity to human health and creating major social problems. This finding implies that, had there been a precautionary measure taken when a new technology tube-well was being introduced, in the form of testing water for harmful metals, the risk that the rural population is facing now could have been drastically reduced. This lack of precautionary measure, before starting a mass installation of tube-wells for drinking and irrigation should be seen as a “human error” and avoided in future water policy and planning.
Cross-Cultural Beliefs about Memory and Aging for Self and Others: South Korea and Canada
Authors: Ryan Ellen Bouchard , Jin Young-Sun , Anas Ann P.
Published: April 2009

Young adults in Canada ( N = 161) and South Korea ( N = 165) rated either themselves or typical others at target ages 25, 45, and 65 years. In both countries, poorer memory was anticipated with each increase in age on all 3 memory belief factors: capacity, change, and locus. Both groups demonstrated a self-protective bias about age-related decline, with Koreans showing a greater effect. These findings demonstrate the cross-cultural generality of negative memory stereotypes of middle and old age and the importance of self-other distinctions in age biases.
Reported Causal Antecedents of Discrete Emotions in Late Life
Authors: Chipperfield Judith G. , Perry Raymond P. , Weiner Bernard , Newall Nancy E.
Published: April 2009

Valuable insights about emotional well-being can be learned from studying older adults who have wrestled with differentiating and regulating their emotions while they navigate through the many joys and traumas of a lifetime. Our objective was to document the underlying reasons for older adults' ( n = 353, ages 72–99) emotional experiences. Using a phenomenological approach, we identified participants' reported reasons (i.e., antecedents) for a broad variety of positive and negative emotions, classifying them into thematic categories through a content analysis. The array of thematic categories that emerged for some emotions was more differentiated than for others. For example, 14 antecedent categories were required to account for the emotion of happiness; whereas, only 4 categories were needed to capture all antecedents for anger. Our analysis provided a rich description of what older adults report as the causes of their emotions, showing that later life is characterized as a time when the loss of love ones elicits sadness, self-limitations elicit frustration, and others' transgressions elicit anger. Yet, our data show that old age can be portrayed even more so as a time when a variety of positive emotions are elicited by social factors (interactions and relationships), achievements, and personal attributes. Finally, in an analysis of the most common antecedents for pride (accomplishments) and anger (other's transgression), we suggest that pride over accomplishments is most likely elicited by internal attributions to skill and effort; whereas, anger over others' transgressions is most likely elicited by controllable attributions to the transgressor's inconsiderate or offensive behavior. Overall, this shows the utility of applying Weiner's attributional framework (Weiner, 1985) to an analysis of emotion antecedents in late life.
Learning from the Disease: Lessons Drawn from Adolescents Having a Grandparent Suffering Dementia
Authors: Celdrán Montserrat , Triadó Carme , Villar Feliciano
Published: April 2009

The objective of this study was to explore what adolescent grandchildren have learned from having a grandparent who suffers dementia and what coping strategies they might recommend for other adolescents in similar situations. We also present information on background factors influencing lessons learned and coping strategies. Adolescent grandchildren living in Barcelona, Spain participated in the study ( N = 138). Qualitative analysis was conducted on responses to 2 open-ended questions regarding lessons learned from having a grandparent with dementia and advice to other grandchildren facing similar situations. Five learning and 4 coping strategies emerged from the analysis. Adolescents reported about the value of life, the complexity of the life-span, and changes in personal characteristics such as patience and responsibility as a result of the experience. Advice to other adolescents primarily focused on accepting the dementia as well as acquiring behavioral coping strategies. Binary logistic regression analysis revealed that type of care grandparent receives—day center versus nursing home—and age of the adolescent influenced lessons learned and coping strategies. Implications for the developmental tasks of the grandchild during adolescence are discussed.
Domestic Economic Policies, Political Institutions, and Transnational Portfolio Investments
Authors: Cao Xun
Published: April 2009

For many, transnational capital is one of the most important driving forces of economic globalization; yet, we know little about what determines cross-border portfolio investments. In addition to recent economic literature's focus on information asymmetries as one key determinant of cross-border investment, this study brings in a political aspect to the field of international trade in assets. The –race to the bottom’ thesis connects domestic economic policies to investment decisions and argues that capital is more likely to move towards economies characterized by economic liberalism; political institutions are also relevant for portfolio investments, because democratic institutions often provide more credible protection against predatory practices. In this study, I model bilateral portfolio investments as a function of economic policies, political institutions, and levels of transparency of sending and receiving countries as well as important international connections. Empirical findings indicate the importance of transparency to attract portfolio investments. Moreover, transnational portfolio investments are only sensitive to some fiscal policy indictors and only within the OECD countries. Therefore, for non-OECD countries, there is still ‘room to move’ in maneuvering different aspects of fiscal policies. Finally, I find that investors care about the nature of political institutions as democratic institutions tend to be associated with higher levels of portfolio investment inflows. This is good news for developing countries that have undergone or are in the process of democratization. In addition to democratizing for peace, increased foreign capital further incentivizes a progression towards democratization.
When Do Firms Prefer Individual Action to Collective Action in The Pursuit of Corporate Political Strategy? A New Perspective on Industry Concentration
Authors: Ozer Mine , Lee Seung-Hyun
Published: April 2009

In this study we advance the current research on corporate political strategy by examining how firms decide on their level of engagement in political action. This study proposes a contingency approach that identifies conditions in which firms prefer individual action to collective action in their pursuit of political strategy and introduces a framework that addresses this preference. Our results show that even in concentrated industries, a firm's preference of individual action over collective action varies when government contracts or research and development intensity are important considerations.
Campaigning as an Industry: Consulting Business Models and Intra-Party Competition
Authors: Grossmann Matt
Published: April 2009

American political campaigns have become a multi-billion dollar industry. Rather than assume that only political factors affect the campaigns that voters see, scholars must assess the importance of the business incentives associated with political consulting. Economic competition does not match political competition; firms compete for clients within the two major parties, against their political allies. I argue that the supply of firms in each party, the revenue models in the industry, the diversification of client types, and the cooperative structure in each party all may affect political campaigns. The way the industry operates and the different patterns of behavior within each party create incentives and practices that may alter campaigns in response to economic factors having little to do with optimal political strategy. Using two original surveys and a network analysis, I analyze how the industry is changing and how consultants in each party cooperate and compete.
Self-Regulation by Associations: Collective Action Problems in European Environmental Regulation
Authors: Héritier Adrienne , Eckert Sandra
Published: April 2009

How and to what effect do firms coordinate their actions to deal with the negative external effects of productive activity? Under which conditions do associations engage in self-regulation and how do they tackle the specific regulatory challenges at stake? When developing hypotheses, we first vary attributes of the information environment in which private actors interact; and, secondly, actors' preferences as a function of the problem type at hand. With respect to the environmental conditions, our findings show that a regulatory threat matters when developing associative action, whilst the evidence is less clear as regards NGO campaigns. In terms of the problem type, we find that redistributive issues and prisoner's dilemma situations are much more conflict prone than coordination/win-win type of problems. Industry actors recur to various governance devices such as flexible contract design and compensation mechanisms to solve redistributive problems. Prisoner's dilemma (PD) problems may only partially be addressed by governance devices to the extent that free-riding is controlled and sanctioned within an association. We conclude that private actors engaging in self-regulation will not successfully manage all types of conflicts. They lack powerful sanctioning tools to deal with PD situations, but prove to be able to flexibly handle redistributive problems.
Effects of Incubation Temperature, Starter Culture Level and Total Solids Content on the Rheological Properties of Yogurt
Authors: Wu Sha , Li Dong , Li Shu-jun , Bhandari Bhesh , Yang Bao-ling , Chen Xiao Dong , Mao Zhi-huai
Published: April 2009

The effects of incubation temperature (35-45oC), starter culture level (0.003-0.006%, w/v), and milk total solids content (12.32-15.68%, w/v) on the rheological properties of yogurt were investigated using central composite rotatable design (CCRD) and response surface methodology (RSM). Gelation time during milk fermentation and apparent viscosity of yogurt stored for 3 days were the rheological parameters studied. The results revealed that the gelation time and apparent viscosity of yogurt were significantly affected (P < 0.1) by incubation temperature, starter culture level, and total solids. Incubation temperature had the greatest influence on the gelation time. Higher temperature led to shorter gelation time, but resulted in lower apparent viscosity of yogurt. Apparent viscosity of yogurt was mainly affected by total solids. Higher apparent viscosities were also obtained at lower incubation temperature.
The Effect of De-Oiled Rice Bran for Single Cell Protein Production Using Fungal Cultures under Solid State Fermentation
Authors: Pogaku Ravindra , Rudravaram Ravinder , Chandel Anuj Kumar , Linga Venkateshwara Rao , Yim Zhi Hui
Published: April 2009

In the present work, de-oiled rice bran (DOB) was exploited for SCP production using three different fungi, namely, Aspergillus oryzae MTCC 1846, Trichoderma viride NRRL 1186 and Aspergillus niger MTCC 1842 under solid state fermentation. DOB was found to contain 9% protein, 39% cellulose, 28% hemicellulose and 24% lignin. All the three cultures have shown more specific growth rate when grown on glucose in comparison to maltose and cellulose. The specific growth rates on glucose were 0.203, 0.201 and 0.196 h-1 and on maltose were 0.173, 0.171, 0.169 h-1 for A. oryzae MTCC 1846, T. viride NRRL 1186 and A. niger MTCC 1842, respectively. All the three microorganisms showed lowest specific growth rate on cellulose 0.119, 0.117, 0.114 h-1 for A. oryzae MTCC 1846, T. viride NRRL 1186 and A. niger MTCC 1842, respectively. The major constituent of dried fungi is crude protein, which contributes to 43% in A. oryzae MTCC 1846, 44% in T. viride NRRL 1186 and 39.2% in A. niger MTCC 1842 on dry basis. Among the three fungi A. oryzae MTCC 1846 shows minimum content of nucleic acids (5.3%) while A. niger MTCC 1842 and T. viride NRRL 1186 showed (6.1%) and (7.2%), respectively.
Thermomechanical Property of Rice Kernels Studied by DMA
Authors: Jia Hai-yan , Li Dong , Lan Yubin , Bhandari Bhesh , Shi John , Chen Xiao Dong , Mao Zhi-huai
Published: April 2009

The thermomechanical property of the rice kernels was investigated using a dynamic mechanical analyzer (DMA). The length change of rice kernels with a loaded constant force along the major axis direction was detected during temperature scanning. The thermomechanical transition occurred in rice kernels when heated. The transition temperatures were determined as 47°C, 50°C and 56°C for the medium-grain rice with the moisture contents of 18.1%, 16.0% and 12.5% (wet basis), respectively. Length change of the rice kernels increased with the increase of the temperature and moisture content. Among the four rice varieties investigated, the results showed that the thermomechanical property was not significantly affected by variety.
The Hispanic-White Achievement Gap in Math and Reading in the Elementary Grades
Authors: Reardon Sean F. , Galindo Claudia
Published: April 2009

This article describes the developmental patterns of Hispanic-White math and reading achievement gaps in elementary school, paying attention to variation in these patterns among Hispanic subgroups. Compared to non-Hispanic White students, Hispanic students enter kindergarten with much lower average math and reading skills. The gaps narrow by roughly a third in the first 2 years of schooling but remain relatively stable for the next 4 years. The development of achievement gaps varies considerably among Hispanic subgroups. Students with Mexican and Central American origins—particularly first- and second-generation immigrants—and those from homes where English is not spoken have the lowest math and reading skill levels at kindergarten entry but show the greatest achievement gains in the early years of schooling.
Lightning induced atrial fibrillation
Authors: Dronacharya L , Poudel R
Published: April 2009

Atrial fibrillation (AF) is a common arrhythmia that occurs in paroxysmal and persistent forms. It occurs in varied situations but lightning induced AF is extremely rare. Here is a case which reverted to sinus rhythm spontaneously. This 37-year-old man without any underlying heart disease had new onset AF after being struck by a lightning. Oral Metoprolol alone was given to control ventricular rate. Spontaneous reversion to sinus rhythm within 36 hours is in favor of new onset lightning induced AF. Key words: Lightning injuries, atrial fibrillation, ECG changes doi: 10.3126/kumj.v6i4.1747     Kathmandu University Medical Journal (2008), Vol. 6, No. 4, Issue 24, 5514-515
Traumatic enucleation with avulsion of the ophthalmic artery resulting in aneurysm-like subarachnoid hemorrhage
Authors: Limbrick David D. , Behdad Amir , Derdeyn Colin P. , Custer Phillip L. , Zipfel Gregory J. , Santiago Paul
Published: April 2009

Traumatic, nonaneurysmal subarachnoid hemorrhage (SAH) is common after closed head injury and most often results from ruptured cortical microvessels. Here, the authors present the case of a 60-year-old woman who fell and struck her head, causing traumatic enucleation and avulsion of both the optic nerve and ophthalmic artery. The arterial avulsion caused a Fisher Grade 3 SAH. During her stay in the intensive care unit, hydrocephalus and vasospasm developed, clinical conditions commonly observed after aneurysmal SAH. Epileptiform activity also developed, although this may have been related to concurrent Pantoea agglomerans ventriculitis. It is reasonable to suggest that intracerebral arterial avulsion with profuse arterial bleeding may be more likely than traditional traumatic SAH to result in clinical events similar to that of aneurysmal SAH. Special consideration should be given to the acute care of patients with intracranial arterial avulsions (conservative management vs surgical exploration or endovascular treatment), as well as long-term follow-up for vascular or other neurosurgical complications.
Subarachnoid hemorrhage and the distribution of drugs delivered into the cerebrospinal fluid
Authors: Pluta Ryszard M. , Butman John A. , Schatlo Bawarjan , Johnson Dennis L. , Oldfield Edward H.
Published: April 2009

Object

Investigators in experimental and clinical studies have used the intrathecal route to deliver drugs to prevent or treat vasospasm. However, a clot near an artery or arteries after subarachnoid hemorrhage (SAH) may hamper distribution and limit the effects of intrathecally delivered compounds. In a primate model of right middle cerebral artery (MCA) SAH, the authors examined the distribution of Isovue-M 300 and 3% Evans blue after infusion into the cisterna magna CSF.

Methods

Ten cynomolgus monkeys were assigned to SAH and sham SAH surgery groups (5 in each group). Monkeys received CSF injections as long as 28 days after SAH and were killed 3 hours after the contrast/Evans blue injection. The authors assessed the distribution of contrast material on serial CT within 2 hours after contrast injection and during autopsy within 3 hours after Evans blue staining.

Results

Computed tomography cisternographies showed no contrast in the vicinity of the right MCA (p < 0.05 compared with left); the distribution of contrast surrounding the entire right cerebral hemisphere was substantially reduced. Postmortem analysis demonstrated much less Evans blue staining of the right hemisphere surface compared with the left. Furthermore, the Evans blue dye did not penetrate into the right sylvian fissure, which occurred surrounding the left MCA. The authors observed the same pattern of changes and differences in contrast distribution between SAH and sham SAH animals and between the right and the left hemispheres on Days 1, 3, 7, 14, 21, and 28 after SAH.

Conclusions

Intrathecal drug distribution is substantially limited by SAH. Thus, when using intrathecal drug delivery after SAH, vasoactive drugs are unlikely to reach the arteries that are at the highest risk of delayed cerebral vasospasm.