bluuebunny/crossref_metadata_2025 huggingface dataset:
Acid–Etched Channels in Heterogeneous Carbonates — A Newly Discovered Mechanism for Creating Acid Fracture Conductivity
Authors: Mou Jianye , Zhu D. , Hill A. D.
Published: January 2009

In the acid fracturing process, the fracture conductivity created by acid etching of the fracture walls is due to the surface roughness created by the acid's non-uniform dissolution of the fracture surfaces. The acid fracture conductivity is dependent on surface etching patterns, which are determined by permeability and mineralogy distributions. That is, the spatial distribution of fracture roughness affects the fracture conductivity, which cannot be considered in laboratory measurements of acid fracture conductivity which use core samples that are too small to observe such macro-scale heterogeneities, nor in typical acid fracture simulations, in which the grid block size is much larger than the scale of local heterogeneities.

An accurate prediction of acid fracture conductivity necessitates the detailed description of the acid etching profiles on the fracture surfaces, which depend on acid transport in the fracture, leakoff due to local permeability, and acid/rock reactions. In this paper, we developed a three dimensional intermediate-scale acid fracture model with grid block sizes small enough and total dimensions large enough to capture local and macro-scale heterogeneity characteristics. The model predicts the pressure field, the flow field, acid concentration profiles, and fracture surface profiles as functions of acid injection volume. In the model, we use a front-fixing method (Crank, 1984) to handle the irregular, moving boundaries in numerical simulation. Spatially correlated permeability and mineralogy distributions were generated by using a semi-variogram model.

The model was validated by comparing simulation results with experimental results from an acid fracture conductivity cell. With the model, we analyzed the relationship among fracture surface etching patterns, conductivities, and the distributions of permeability and mineralogy. We also illustrated the formation characteristics necessary for acid to create channel-caused high acid fracture conductivity. We found that a fracture segment with channels extending from the inlet to the outlet of the segment has high conductivity because fluid flow in deep channels needs a very small pressure drop. Such long and highly conductive channels can be created by acids if the formation has heterogeneities in either permeability or mineralogy, or both, with strong correlation strength in the main flow direction, which is the case in laminated formations.
Modeling Fracture Fluid Cleanup in Tight Gas Wells
Authors: Wang John Yilin , Holditch Stephen A. , McVay Duane A.
Published: January 2009

On occasion, a hydraulically fractured tight gas well does not perform up to its potential because of slow or incomplete fracture fluid cleanup. A number of papers have been written to address individual factors related to fracture fluid cleanup, but there are still many unanswered questions as to which factors mostly affect gas production from such wells. Numerical reservoir simulation is one of the best methods to study the fracture fluid cleanup problem. Continuing from our previous publication (SPE 117444) on the impact of gel damage on fracture cleanup, we used reservoir simulation to analyze systematically the factors that affect fracture fluid cleanup and gas recovery from tight gas wells.

We first developed a comprehensive data set for typical tight gas reservoirs, and then ran single-phase flow cases for each reservoir and fracture scenario to establish the idealized base-case gas recovery. We then systematically evaluated the following factors: multiphase gas and water flow, proppant crushing, polymer filter cake, and finally yield stress of concentrated gel in the fracture. The gel in the fracture is concentrated due to fluid leakoff during the fracture treatment. We evaluated these factors additively in the order listed. We found that the most important factor that reduces fracture fluid cleanup and gas recovery is the gel strength of the fluid that remains in the fracture at the end of the treatment.

This paper illustrates the complexity of the fracture fluid cleanup problem and points out the need to use reservoir simulation and to include all the pertinent factors in order to rigorously model fracture fluid cleanup. The procedures presented can provide a useful, systematic guide to engineers in conducting a numerical simulation study of fracture fluid cleanup.
Fracture Containment in Soft Sands by Permeability or Strength Contrasts
Authors: de Pater C. J. , Dong Y.
Published: January 2009

We have conducted laboratory tests to investigate the containment of hydraulic fractures in unconsolidated, layered formations. We varied both permeability and strength of the layers in the samples. The fracture evolution was observed with X-Ray CT scanning and by excavating the sample after the test.

We found that permeability is the dominant factor in containment, if the stress contrast is small. With a factor of three to four between the permeability of the two layers there is a strong tendency for the fracture to propagate in the low permeability layer. Difference in strength is much less important for containment.

A numerical fracture propagation model described the sand as an elasto-plastic material with parameters obtained from triaxial tests and used a simplified leak-off description of the cross-linked gel. The results agree qualitatively with the tests.
Barnett Shale Refracture Stimulations Using a Novel Diversion Technique
Authors: Potapenko D. I. , Tinkham S. K. , Lecerf B. , Fredd C. N. , Samuelson M. L. , Gillard M. R. , Le Calvez J. H. , Daniels J. L.
Published: January 2009

Gas production from the unconventional Barnett Shale reservoir now exceeds 3 Bcf/d, which is more than 5% of total U.S. dry gas production. Typically Barnett Shale wells exhibit a rapid production decline following the initial hydraulic fracture stimulation treatment, so that, within 5 years, an operator is normally faced with a well producing below its economic threshold. To keep up with current gas demand, operators have moved to an aggressive horizontal drilling and completion program. Additionally, in an effort to increase the productivity of existing wells and book additional reserves at reduced cost, operators have restimulated their older vertical wells, with demonstrable success. This success is providing compelling opportunities to enhance refracture treatment coverage by targeting bypassed and ineffectively stimulated zones in additional vertical wells and even some horizontal wells. Because of the heterogeneous nature of this unconventional gas reservoir, the restimulation of horizontal wells is problematic, and operators have demonstrated limited success using current stimulation techniques.

This paper describes a new fracture diversion technique particularly adapted for horizontal well refracture stimulation. During the treatment, a fracture diversion system (FDS) is used to create a temporary bridge within the active fracture networks. That results in differential pressure increase and causes treatment redirection to understimulated intervals along the lateral. This technique enables both fracture diversion without mechanical intervention and, when enhanced with microseismic monitoring, real-time optimization of the fracturing treatment.

Refracture stimulation case studies are presented in which this novel diversion technique is successfully applied to horizontal Barnett Shale wells. This paper demonstrates how real-time hydraulic fracture monitoring has enabled operators to make informed decisions that influence fracture geometry, increase lateral coverage, and improve gas recovery. To date, more than 20 fracture diversion designs have been successfully placed. The trial wells have included both cemented and uncemented completions, with drilled azimuths selected to encourage either transverse or longitudinal fracture fairway development. With a continuing optimization of the described refracturing technique, these FDS designs and placement strategies have evolved to the point where they are consistently exhibiting fracture diversion as evidenced by movement of microseismic activity and improved lateral coverage.

While this engineered fracture diversion technique is ideally suited for re-fracture stimulations, it is also applicable for stimulation of new wells where the technique enables stimulation of larger wellbore intervals when used in the same fashion as for re-fracture stimulation applications.
Fiber-Laden Fluid—Applied Solution for Addressing Multiple Challenges of Hydraulic Fracturing in Western Siberia
Authors: Sitdikov S. , Serdyuk A. , Nikitin A. , Yudin A. , Mullen K. , Oussoltsev D. , Butula K. K.
Published: January 2009

This paper describes successful implementation of degradable fiber-laden fluids for hydraulic fracturing in one of the largest oilfield in Western Siberia. Placement advantage of fiber-assisted fluid already becomes obvious after initial campaign of four fracturing treatments. It demonstrated good proppant carrying capabilities and allowed decrease of polymer load without increasing risk of premature screenout. Fibers proved to be reliable for successful placement of 10/14-mesh size Intermediate Strength Proppants (ISP) at concentration up to 1000 kgPA and higher with only 3.0 kg/m3 (25lb/1000gal) guar polymer loading, a feat previously only achievable with 3.6-4.2 kg/m3 (30-35lb/1000gal) gel loading in similar geological conditions.

In addition to reducing damage with lower polymer concentrations, other advantages of degradable fiber usage were anticipated to be proven after proppant fractures geometries and production parameters (including PI and Jd) evaluation. Analyses of the fracturing treatments have been performed based on bottomhole pressure gauges data and well-supported with direct fracture geometry estimation obtained by using differential cased hole sonic anisotropy measurements. As it is common for most formations in Western Siberia to have high degree of lamination and multiple shaly layers inside producing zone, pilot well-candidates for the project were specifically selected to have complex geology including several layers of sandstones and shaly strikes. This requires the fracture to intersect layers of sandstone and provide optimum connection for hydrocarbons flow to the wellbore, by evenly distributing proppant throughout the height of the fracture. Thus, degradable fiber-assisted fluid must be utilized, as conventional fracturing fluids may not suspend proppant for required time period and proppant settling during fracture closure results in considerable part of net pay being under stimulated.

The laboratory testing on large size ISP proppant suspension by degradable fiber in viscous fluids was performed for this project and described in the paper.

Western Siberia field and degradable fiber-laden fluid provided a good example of how one solution may be applied for various challenges of hydraulic fracturing optimization. This research will present a comprehensive story supported by technical analyses.
Tank irrigation in India: a time series analysis
Authors: Narayanamoorthy A.
Published: January 2009

Tanks are one of the important traditional sources of irrigation in India, irrigating nearly three million hectares even today. Though considered to be a low cost source with few environmental problems, the performance of tank irrigation has been poor and has deteriorated over the years. Several studies have analysed the performance of tank irrigation using field survey data, but not many studies seem to have analysed the trends and determinants of tank irrigation covering various states as well as national level data in recent times. In this study, therefore, using time series data from 1950/51 to 1999/2000, an attempt is made (a) to study the growth pattern of tank irrigation across different periods both at the national as well as across states level, (b) to study the nexus between rainfall and area under tank irrigation at a specific state, which has relatively larger area under tank irrigation, (c) to find out the losers and gainers of tank irrigation among different size of farmers, and (d) to suggest policy measures to rejuvenate tank irrigation in India.
An approach to assessing socioeconomic implications of water management alternatives
Authors: Prasad Krishna C. , Strzepek Kenneth M. , van Koppen Barbara
Published: January 2009

Socioeconomic development objectives are integral to the integrated river basin management initiatives in several river basins around the world, including the Olifants River Basin of South Africa. All viable strategic water management alternatives are expected to contribute towards such, usually predefined, socioeconomic objectives in addition to other hydrological and ecological objectives. An assessment of the relative merits of different alternatives becomes imperative to trace the respective contributions of the alternatives to such objectives and thus to identify the best-bet and most agreeable alternative from a multi-stakeholders' perspective. This paper reports key findings from application of a methodology for this purpose in the Olifants River Basin of South Africa by (a) establishing a link between water management indicators and socioeconomic objectives, (b) assessing the potential socioeconomic implications of various water management alternatives and (c) rank ordering the identified alternatives against the socioeconomic objectives based on multi-criteria decision analysis techniques.
Water as a political good: revisiting the relationship between politics and service provision
Authors: Schwartz Klaas , Schouten Marco
Published: January 2009

Because water services are a private good, a merit good, an economic good and subject to market failure, the provision of water services features prominently on the political agenda in many countries, essentially making it a “political good”. Being a political good, the majority of water supply and sanitation services are still provided by public sector organizations. These public utilities have often provided very poor services and one of the main causes of the failure to provide adequate services is the political involvement in the sector. As a result, many professionals have called for the stringent separation of the political realm from service provision.

In this article it is argued that the realities of the water services sector are such that a stringent separation of the political realm from the management of the service provider is unrealistic, if not naive. Moreover, the article seeks to present a more nuanced view of the relationship between politics and service provision by arguing that service providers, who have improved services significantly, have been able to do so because of support from the political realm, which extended well beyond the activities of making policy.
Investigating the Optimal Soy Protein and Isoflavone Intakes for Women: A Perspective
Authors: Messina Mark
Published: January 2009

Traditional soyfoods have been consumed for centuries throughout much of East Asia and, recently, these foods have also become popular in the West. Soyfoods and specific soybean components, such as the protein and isoflavones, have attracted attention for their possible health benefits. Isoflavones are classified as phytoestrogens and have been postulated to be natural alternatives to hormone therapy for menopausal women. To provide guidance on optimal soy intake, this article evaluates Asian soy consumption and both clinical and Asian epidemiologic studies that examined the relationship between soy intake and a variety of health outcomes. On the basis of these data and the standard principles of dietary practice the author suggests that optimal soy protein and isoflavone intakes are 15–20 g/day and 50–90 mg/day, respectively. In addition, an intake of 25 g/day soy protein can be specifically used as the recommendation for cholesterol reduction.
Malignancies in Women with HIV Infection
Authors: Krishnan Amrita , Levine Alexandra M
Published: January 2009

Women with HIV infection have an increased risk of developing certain malignancies. These malignancies are commonly human papillomavirus (HPV)-related, reflecting the high rate of coinfection with HPV in women with underlying HIV infection. These women also have a high incidence of premalignant HPV-related changes, such as high-grade squamous intraepithelial lesions as diagnosed on Pap smears and cervical intraepithelial neoplasia on cervical biopsy. Screening recommendations for HIV-infected women reflect the need for vigilance in detecting and treating these lesions early. In addition, recent interest has focused on the use of cervical cancer screening, employing HPV-testing techniques, and on HPV vaccination in younger women to prevent initial infection and the subsequent development of cervical and other HPV-related cancers. The incidence of other types of malignancies, such as Hodgkin's and non-Hodgkin's lymphoma, is also increased in HIV-infected individuals. When these lymphomas occur, they tend to be of advanced stage and high-grade histologies. The advent of highly active antiretroviral therapy has been associated with a marked decrease in the incidence of some of these cancers. The use of therapy has been associated with marked improvement in response rates and overall survival of affected patients.
Decay of passively acquired measles antibody and its implications for vaccination
Authors: Rahman ASM Matiur
Published: January 2009

doi:10.3329/jafmc.v4i2.1818JAFMC Bangladesh Vol.4(2) 2008 1
Protein energy malnutrition curse of poverty
Authors: Habib Md Absan
Published: January 2009

doi:10.3329/jafmc.v4i2.1819JAFMC Bangladesh Vol.4(2) 2008 2-3
Study on measles antibody status in children below nine months of age and its implication on measles vaccination
Authors: Chowdhury Jamal Pasha , Mondol Md Eunus Ali , Uddin Muhammad Jalal , Hoque Md Monirul , Kawser Narjis Maliha , Rahim Ina , Wadud ABM Abdul
Published: January 2009

doi:10.3329/jafmc.v4i2.1820 JAFMC Bangladesh Vol.4(2) 2008 5-9
Antimicrobial susceptibility patterns of Î²-lactamase producing Staphylococcus Aureus
Authors: Kawsar Narjis Maliha , Mondal Md Eunus Ali , Khan Nizamul Karim , Jubaida Nishat , Chowdhury Jamal Pasha , Khan Luthunnahar
Published: January 2009

doi:10.3329/jafmc.v4i2.1838JAFMC Bangladesh Vol.4(2) 2008 14-17
Diagnostic evaluation of pleural fluid: the role of total protein and lactic dehydrogenage
Authors: Rahman Md Sayedur , Siddiqui Md Abdul Moyeed , Rabbani Md Golam , Nazimuddin Md , Al-Farooque Abdullah , Hasan SM Mahmudul , Bhuiyan Md Abdul Quddus , Ara Mah Jabeen
Published: January 2009

doi:10.3329/jafmc.v4i2.1839 JAFMC Bangladesh Vol.4(2) 2008 18-20
A healthy pregnancy following chemotherapy for dysgerminoma
Authors: Begum H , Nahar K , Moniruddin ABM , Majumder NA
Published: January 2009

doi:10.3329/jafmc.v4i2.1846 JAFMC Bangladesh Vol.4(2) 2008 42-43
Motion Simulation of a Fine Shaped Vessel at Hiron Point in the Bay of Bengal
Authors: Islam M Rafiqul , Hassan Md Munir , Baree Md Sdaiqul
Published: January 2009

The hydrodynamic behaviour of a fast fine vessel is of great importance than that of a fuller vessel as the fast fine vessels are engaged for important operations. Moreover with the advent of modern computers, in ship hydrodynamics, 3-D source distribution method is gaining much popularity and normally applied for blocky hull. But in the case of finer hull, examples are rare especially considering forward speed effect. With these views in mind, in the present research work, effort has been given to develop a mathematical model for fine shape vessel to predict and simulate her motions in irregular waves. A computer program has been developed on the basis of mathematical model and to examine the validity of the developed program, results for hydrodynamic coefficient and motions of a series 60 ship have been compared with Gerristma's experimental results and with the results based on other codes. After validation of the program, simulation of motions of an existing the fine shape ship has been carried out at Hiron point of the Bay of Bengal by utilizing hydrodynamic coefficients and wave exciting forces and moments obtained in regular waves and a new wave spectrum formula based on wave data at the concerned location. On the basis of the results presented, it may be concluded that the developed model based on 3-D distribution technique can be applied for prediction of motion of fine shape ship with forward speed effect. Moreover limitations of operation of the vessel have been demonstrated at various combinations of significant wave heights and speeds. doi:10.3329/jname.v2i2.1870 Â Journal of Naval Architecture and Marine Engineering 2(2005) 25-40
Modeling of Annular Prediffuser for Marine Gas Turbine Combustor using CFD - A Study on the Effect of Strut Configuration
Authors: Sheeba A , Ganesan V
Published: January 2009

This paper presents the numerical and experimental investigation of a straight core annular diffuser normally used in marine gas turbine combustor. The flow in the annular diffuser has been simulated by solving the equations for conservation of mass and momentum. For turbulence modeling the standard k-Îµ model is employed and the predicted results have been validated with experiments. A five-hole probe and a single normal hot wire anemometer were used to measure mean and fluctuating components of velocity. The comparison of the experimental and predicted mean velocity values in radial direction, at different axial locations of annular diffuser is presented and discussed. Flow development in the annular diffuser with different strut geometries has been analyzed. The discussion is focused on the distortion of the flow produced by the strut configuration. Keywords: Annular Diffuser, Struts, Recirculation Region Â  doi:10.3329/jname.v2i2.1871 Â Journal of Naval Architecture and Marine Engineering 2(2005) 41-52
Natural Convection Flow from an Isothermal Sphere with Temperature Dependent Thermal Conductivity
Authors: Molla Md Mamun , Rahman Azad , Rahman Lineeya Tanzin
Published: January 2009

Laminar free convection flow from an isothermal sphere immersed in a fluid with thermal conductivity proportional to linear function of temperature has been studied. The governing boundary layer equations are transformed into a non-dimensional form and the resulting nonlinear system of partial differential equations is reduced to local non-similarity equations, which are solved numerically by very efficient implicit finite difference method together with Keller box scheme. Numerical results are presented by velocity and temperature distribution of the fluid as well as heat transfer characteristics, namely the heat transfer rate and the skin-friction coefficients for a wide range of thermal conductivity parameter Î³ (= 0.0, 0.5, 1.0, 2.0, 3.0, 5.0) and the Prandtl number Pr (= 0.7, 1.0, 3.0, 5.0, 7.0). Â  Keywords: Natural convection, temperature dependent thermal conductivity, isothermal sphere. Â Â  doi:10.3329/jname.v2i2.1872 Â Journal of Naval Architecture and Marine Engineering 2(2005) 53-64
A Comparative Study of Two Passenger Transportation Systems between Two Bangladeshi Cities
Authors: Iqbal K Shahriar , Shil Samir K
Published: January 2009

Using life cycle impact assessment, required freight rate and the customer service time, the ecological impact and the economic performance of bus and water transportation systems were evaluated and compared for the Dhaka - Narayanganj route in Bangladesh. Then the benefit of modal shifting of passengers from bus to water transport is shown. The results are shown as three different comparison indices. The water transportation showed clear superiority in environmental and economic aspects. Only the âservice quality' went to the favor of bus. Â  Keywords: Inland water transport, transportation planning, environmental pollution, life cycle assessment, Â sustainable development, Kyoto Protocol. Â Â Â doi:10.3329/jname.v2i2.928Â Journal of Naval Architecture and Marine Engineering 2(2005) 1-10
Smoking Status, Changes in Smoking Status and Health-Related Quality of Life: Findings from the SUN (“Seguimiento Universidad de Navarra”) Cohort
Authors: Guitérrez-Bedmar Mario , Seguí-Gómez María , Gómez-Gracia Enrique , Bes-Rastrollo Maira , Martínez-González Miguel   A.
Published: January 2009

We aimed to evaluate the association between smoking, changes in smoking, and quality of life in a cohort of Spanish university graduates. Smoking habits were self-reported at baseline and four years later. Quality of life was assessed using the Short Form-36 (SF-36) at year 4. Statistical differences in SF-36 scores between groups were determined using ANCOVA with age and sex as covariates. Out of 5,234 eligible participants over 2000-2006, there were 2,639 non-smoker participants, 1,419 ex-smokers, and 1,048 smokers. Within the previous four years, 435 participants became recent quitters and 205 starters. Comparing smoking and health status in year 4, non-smokers showed better scores than the other categories of ever smoking in all dimensions except in the vitality scale value, which was similar in non-smokers and in those smoking less than 15 cigarettes/day. Comparing changes in smoking and health in year 4, continuing smokers had statistically significant worse scores than non-smokers in general health, social functioning, role-emotional and mental health, whereas recent quitters showed statistically significant improvements in role-emotional and mental health over those who had continued smoking or those who became smokers. Our findings support a dose-response relationship between cigarette consumption and a worse quality of life in general and mental health in particular. They also support that changes in smoking have an impact on health.
Multiscale Modeling of Dendrimers and Their Interactions with Bilayers and Polyelectrolytes
Authors: Lee Hwankyu , Larson Ronald  G.
Published: January 2009

Recent advances in molecular dynamics simulation methodologies and computational power have allowed accurate predictions of dendrimer size, shape, and interactions with bilayers and polyelectrolytes with modest computational effort. Atomistic and coarse-grained (CG) models show strong interactions of cationic dendrimers with lipid bilayers. The CG simulations with explicit lipid and water capture bilayer penetration and pore formation, showing that pore formation is enhanced at high dendrimer concentration, but suppressed at low temperature and high salt concentration, in agreement with experiments. Cationic linear polymers have also been simulated, but do not perforate membranes, evidently because by deforming into a pancake, the charges on a linear polymer achieve intimate contact with a single bilayer leaflet. The relatively rigid dendrimers, on the other hand, penetrate the bilayer, because only by interacting with both leaflets can they achieve a similar degree of contact between charged groups. Also, a “dendrimer-filled vesicle” structure for the dendrimer-membrane interaction is predicted by mesoscale thermodynamic simulations, in agreement with a picture derived from experimental observations. In simulations of complexes of dendrimer and polyelectrolyte, anionic linear chains wrap around the cationic dendrimer and penetrate inside it. Overall, these new results indicate that simulations can now provide predictions in excellent agreement with experimental observations, and provide atomic-scale insights into dendrimer structure and dynamics.
Mechanochemical Solvent-Free and Catalyst-Free One-Pot Synthesis of Pyrano[2,3-d]Pyrimidine-2,4(1H,3H)-Diones with Quantitative Yields
Authors: Mashkouri Sara , Reza Naimi-Jamal M.
Published: January 2009

Solvent-free synthesis of pyrano[2,3-d]pyrimidine-2,4(1H,3H)-diones by ball-milling and without any catalyst is described. This method provides several advantages such as being environmentally friendly, using a simple workup procedure, and affording high yields.
Ricin Detection Using Phage Displayed Single Domain Antibodies
Authors: Goldman Ellen  R. , Liu Jinny L. , Bernstein Rachael  D. , Swain Marla  D. , Mitchell Stanley  Q. , Anderson George  P.
Published: January 2009

Phage-displayed single domain antibodies (sdAb) were compared to monomeric solubly expressed sdAb and llama polyclonal antibodies for the detection of ricin. SdAb are comprised of the variable domain derived from camelid heavy chain only antibodies (HcAb). Although HcAb lack variable light chains, they as well as their derivative sdAb are able to bind antigens with high affinity. The small size of sdAb (~16 kDa), while advantageous in many respects, limits the number of labels that can be incorporated. The ability to incorporate multiple labels is a beneficial attribute for reporter elements. Opportunely, sdAb are often selected using phage display methodology. Using sdAb displayed on bacteriophage M13 as the reporter element gives the potential for incorporating a very high number of labels. We have demonstrated the use of both sdAb and phage- displayed sdAb for the detection of ricin using both enzyme linked immunosorbent assays (ELISAs) and Luminex fluid array assays. The phage-displayed sdAb led to five to ten fold better detection of ricin in both the ELISA and Luminex assays, resulting in limits of detection of 1 ng/mL and 64 pg/mL respectively. The phage-displayed sdAb were also dramatically more effective for the visualization of binding to target in nitrocellulose dot blot assays, a method frequently used for epitope mapping.
Language use predicts phenomenological properties of Holocaust memories and health
Authors: Boals Adriel , Perez Alison Stern
Published: January 2009

Twenty Holocaust survivors gave extensive interviews about their experiences in the Holocaust and their lives since. This study affords a rare opportunity to explore language use and trauma using a within‐subjects design. Consistent with past research which has shown that cognitive word use typically increases when describing stressful experiences, participants used a higher percentage of cognitive words when describing their Holocaust experiences, in comparison to describing non‐Holocaust experiences. Four years after the interviews, participants completed memory questionnaires in relation to their Holocaust experiences and measures of physical health and cognitive functioning. The extent to which participants used an elevated use of insight words when describing their Holocaust experiences 4 years earlier was related to lower ratings of visceral emotional reactions, less avoidance and better lifetime physical health. The results are discussed in terms of how use of cognitive words when describing traumatic memories reflects adaptive psychological and coping processes. Copyright © 2009 John Wiley & Sons, Ltd.
Enantioselective Synthesis of Chiral β‐Aryloxy Alcohols by Asymmetric Hydrogenation of α‐Aryloxy Aldehydes via Dynamic Kinetic Resolution
Authors: Zhou Zhang‐Tao , Xie Jian‐Hua , Zhou Qi‐Lin
Published: January 2009

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A catalytic enantioselective hydrogenation of racemic α‐aryloxy aldehydes via dynamic kinetic resolution has been developed by using (diamine)(spirodiphosphine)ruthenium(II) chloride [RuCl2(SDPs)(diamine)] catalysts. Employing this new reaction system a variety of optically active β‐aryloxy primary alcohols were synthesized in high yields and moderate to good enantioselectivities.
Job strain and the risk for occupational injury in small‐ to medium‐sized manufacturing enterprises: A prospective study of 1,209 Korean employees
Authors: Kim Hwan‐Cheol , Min Jin‐Young , Min Kyoung‐Bok , Park Shin‐Goo
Published: January 2009

Background

The aim of this study was to investigate whether job strain had an effect on the risk of occupational injury of workers at small‐ to medium‐sized manufacturing companies.

Methods

We conducted a prospective follow‐up survey and finally 1,209 workers in South Korea were included in this study. At time X1, we measured job stress with the Job Demand and Decision Latitude Questionnaire; and at time X2 (after 6 months), we evaluated occupational injuries through a single question. Occupational injuries were assessed using the question “Have you ever been injured at work, including minor scratches and cuts, in the previous four‐month period” by self‐reporting in the previous 4‐month period.

Results

For men, the high job‐demand group (OR = 1.71, 95% CI = 1.13–2.59) and high strain group (OR = 1.79, 95% CI = 1.02–3.14) showed the increased risk of occupational injury. For women, high job‐demand (OR = 2.11, 95% CI = 1.18–3.78), low job control (OR = 1.80, 95% CI = 1.02–3.17), and high job strain (OR = 3.57, 95% CI = 1.62–7.86) were significantly associated with occupational injury.

Conclusion

Workers under high job strain showed higher risk for occupational injury. The efforts to minimize stress‐related occupational injuries should be required. Am. J. Ind. Med. 52:322–330, 2009. © 2009 Wiley‐Liss, Inc.
RNA‐Interferenz: von den Grundlagen zur therapeutischen Anwendung
Authors: Kurreck Jens
Published: January 2009

Ein effizienter Mechanismus zur sequenzspezifischen Inhibition einer Genexpression ist die RNA‐Interferenz. Hierbei führen doppelsträngige RNA‐Moleküle zur Spaltung der ausgewählten Ziel‐RNA (siehe Bild). Diese Technik hat sich in den vergangenen Jahren zu einer Standardmethode der Molekularbiologie entwickelt, die nach erfolgreichen Anwendungen im Tiermodell bereits in klinischen Studien als neue Therapieform erprobt wird.

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Vor gerade einmal zehn Jahren konnten Andrew Fire und Craig Mello zeigen, dass doppelsträngige RNA‐Moleküle in Eukaryoten die Expression homologer Gene posttranskriptionell inhibieren können. Dieser als RNA‐Interferenz bezeichnete Prozess hat sich mittlerweile zu einer Standardmethode der Molekularbiologie entwickelt. Der vorliegende Aufsatz gibt einen Überblick über die zugrunde liegenden zellulären Vorgänge mit besonderem Fokus auf die posttranskriptionelle Inhibition der Genexpression in Säugerzellen, die Anwendungsmöglichkeiten in der Forschung und die ersten Ergebnisse der bereits laufenden klinischen Studien.
Pseudo‐Bridging Silanols as Versatile Brønsted Acid Sites of Amorphous Aluminosilicate Surfaces
Authors: Chizallet Céline , Raybaud Pascal
Published: January 2009

Amorphisierung regelt Säurestärke: Pseudo‐verbrückende Silanole, die in Modellrechnungen als anpassungsfähige Brønsted‐saure Gruppen identifiziert wurden, entstehen durch Hydrolyse von Si‐O‐Al‐Brücken, die durch Abscheiden von Siliciumoxid auf γ‐Al2O3(100) und anschließendes Erhitzen erzeugt wurden. Eine teilweise Entmischung des Siliciumoxids aus dem Alumosilicat nach der Adsorption eines Überschusses an Wasser wird vorhergesagt.

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RNA Interference: From Basic Research to Therapeutic Applications
Authors: Kurreck Jens
Published: January 2009

An efficient mechanism for the sequence‐specific inhibition of gene expression is RNA interference. In this process, double‐stranded RNA molecules induce cleavage of a selected target RNA (see picture). This technique has in recent years developed into a standard method of molecular biology. Successful applications in animal models have already led to the initiation of RNAi‐based clinical trials as a new therapeutic option.

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Only ten years ago Andrew Fire and Craig Mello were able to show that double‐stranded RNA molecules could inhibit the expression of homologous genes in eukaryotes. This process, termed RNA interference, has developed into a standard method of molecular biology. This Review provides an overview of the molecular processes involved, with a particular focus on the posttranscriptional inhibition of gene expression in mammalian cells, the possible applications in research, and the results of the first clinical studies.
Pseudo‐Bridging Silanols as Versatile Brønsted Acid Sites of Amorphous Aluminosilicate Surfaces
Authors: Chizallet Céline , Raybaud Pascal
Published: January 2009

Amorphization tunes acidity: Pseudo‐bridging silanols, suggested as versatile Brønsted acid groups by molecular modeling studies, are obtained by shifted hydrolysis of SiOAl bridges formed by the thermal treatment of silica deposited on γ‐Al2O3 (100), and appear under given pretreatment conditions. Demixing of part of the silica from the aluminosilicate phase is predicted upon excess water adsorption.

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Ruthenium‐Catalyzed Synthesis of Functionalized Dienes from Propargylic Esters: Formal Cross‐Coupling of Two Carbenes
Authors: Vovard‐Le Bray Chloé , Dérien Sylvie , Dixneuf Pierre H.
Published: January 2009

Cross‐coupling carbenes: The coupling of a propargylic ester with a diazoalkane in the presence of [RuCl(cod)Cp*] catalyst leads to the formation of functionalized conjugated dienes with high stereoselectivity. The reaction involves the cross‐coupling of a vinylcarbene fragment, arising from a ruthenium‐catalyzed propargylic ester rearrangement, with a diazoalkane carbene.

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Basking site and water depth selection by gharial Gavialis gangeticus Gmelin 1789 (Crocodylia, Reptilia) in National Chambal Sanctuary, India and its implication for river conservation
Authors: Hussain Syed Ainul
Published: January 2009

The species diversity of inland waters is among the most threatened of all ecosystems and in many parts of the world it is in continuing and accelerating decline. Such decline could be restrained by acknowledging the scope of target species, so that all relevant stages in their life cycle are considered.

The gharial Gavialis gangeticus is a prominent riverine species of the Indus, Ganges, Brahmaputra and Mahanadi river systems that is becoming increasingly rare due to reduction in water flow and available nesting beaches, modification of river morphology and increased mortality in fishing nets. Despite these threats, scientific information on habitat selection by gharial is still inadequate, which hinders conservation measures.

This paper presents the population status, basking site selection and water depth preferences of different size‐classes of gharial based on a study conducted in the National Chambal Sanctuary, India.

Between 1992 and 2007 a 40% decline in the gharial population was observed in the National Chambal Sanctuary. The decline was prominent in the recruitment class (<120 cm), which primarily comes from the nests laid in the wild, and also in sub‐adults (>180 to 270 cm) comprising both wild and reintroduced gharial.

Along the Chambal River, gharial preferred sandy parts of the river banks and sand bars for basking and showed less preference for rocky river banks and rocky outcrops. Clay river banks were least preferred.

Juvenile gharials <120 cm and 120–180 cm preferred water depths 1–3 m and 2–3 m, respectively. Gharial >180 cm (including sub‐adults and adults) preferred water depths >4 m.

Increasing demands for sand for development activities, and water abstraction for irrigation and energy generation coupled with mortality in fishing nets, are likely to affect gharial and other aquatic species, and steps need to be taken to maintain the minimum river flow necessary to sustain ecosystem processes.

Copyright © 2009 John Wiley & Sons, Ltd.
Potassium tert‐Butoxide‐Catalyzed Dehydrogenative SiO Coupling: Reactivity Pattern and Mechanism of an Underappreciated Alcohol Protection
Authors: Weickgenannt Andreas , Oestreich Martin
Published: January 2009

As simple as it gets! Potassium tert‐butoxide alone catalyzes the direct dehydrogenative SiO coupling of several synthetically important silanes with 1°, 2°, and even 3° alcohols without the need for stoichiometric hydrochloric acid scavengers. The stereoretentive mechanism is probed with a silicon‐stereogenic silane.

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A remarkable tert‐butoxide‐catalyzed coupling of alcohols and silanes is reported. Dihydrogen and not hydrochloric acid (generated in the prevalent, related coupling of alcohols and chlorosilanes) is formed as the sole by‐product. A comprehensive survey of common silanes provides a reliable tool for the predictability of their reactivity under defined reaction conditions. The debated mechanism of this transformation is investigated monitoring the stereochemical course at the silicon atom by means of a silicon‐stereogenic silane. On this basis, a transition state for the enantiospecific SiO coupling step is suggested rationalizing the observed frontside attack and thus retention at the silicon atom.
Innovation of visualized interactive tools for learning molecular simulation curriculum
Authors: Sung Wen‐Tsai , Chung Hung‐Yuan
Published: January 2009

The goal of molecular simulation stability is to predict the detailed structure and physical properties of molecules in bioengineer's experiment curriculum. This work succeeds in citing minimum energy and some computer graphics technologies to support this theme. Molecular structure is that given the uncountable number of possible conformations for a protein, how we can determine the lowest energy structure. In this article the authors employed the previous researches‐WebDeGrator and some existing molecular graphics tools to simulate various protein folding, ligand acceptor interaction, and molecular visualization. For this reason, bioengineer experimental curriculum will be visualization and interactive among learning members. Finally, Simpson's Taxonomy and pre‐ and post‐test examinations are applied to System Evaluation, and molecular simulation and minimum energy will be discussed. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 28–40, 2010; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20226
PerfPred: A web‐based tool for exploring computer architecture design space
Authors: Beg Azam , Ibrahim Walid
Published: January 2009

This paper presents a Web‐based tool for predicting the performance of computer systems. The tool can be used for teaching how the hardware configurations (processor microarchitecture, memory hierarchy, etc.) and/or software (benchmark program) characteristics can affect the system throughput. Use of the proposed tool in computer architecture classes has demonstrated its effectiveness in improving the students' understanding of the related topics. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 305–313, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20243
Mechanism of the Coupling of Diazonium to Single‐Walled Carbon Nanotubes and Its Consequences
Authors: Schmidt Grégory , Gallon Salomé , Esnouf Stéphane , Bourgoin Jean‐Philippe , Chenevier Pascale
Published: January 2009

On the tube: The coupling of diazonium ions onto single‐walled carbon nanotubes is shown to proceed through a radical chain reaction by kinetic analysis of the absorption peak drop (see picture). Radical species are also revealed by ESR. Metallic (m) nanotubes play a special catalytic role in the functionalization of semiconducting (sc) nanotubes.

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Due to its simplicity and versatility, diazonium coupling is the most widely used method for carbon nanotube (CNT) functionalization to increase CNT processability and add new functionalities. Yet, its mechanism is so far mostly unknown. Herein, we use kinetic analysis to shed light on this complex mechanism. A free‐radical chain reaction is revealed by absorption spectroscopy and ESR. Metallic CNTs are shown to play an unexpected catalytic role. The step determining the selectivity towards metallic CNTs is identified by a Hammett correlation. A mechanistic model is proposed that predicts reactivity and selectivity as a function of diazonium electrophilicity and metallic‐to‐semiconducting CNT ratio, thus opening perspectives of controlled high‐yield functionalization and purification.
Size Selection During Crystallization of Oppositely Charged Nanoparticles
Authors: Kowalczyk Bartlomiej , Kalsin Alexander M. , Orlik Rafal , Bishop Kyle J. M. , Patashinskii Alexander Z. , Mitus Antoni , Grzybowski Bartosz A.
Published: January 2009

Opposites attract (selectively): Oppositely charged nanoparticles characterized by different size distributions form 3D supracrystals (see figure) only if the distributions overlap. Crystal quality decreases rapidly with decreasing degree of overlap, and, irrespective of the ratio of particle diameters/charges, no crystals are observed for non‐overlapping distributions.

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ChemInform Abstract: Easy Access to Triazoles, Triazolopyrimidines, Benzimidazoles and Imidazoles from Imidates.
Authors: Zarguil A. , Boukhris S. , El Efrit M. L. , Souizi A. , Essassi E. M.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Anionic Condensations of 3,5‐Di‐tert‐butyl‐4(2)‐hydroxybenzaldehydes in the Presence of Weak Bases.
Authors: Vol'eva V. B. , Belostotskaya I. S. , Komissarova N. L. , Kurkovskaya L. N.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Greater Variety in Groebke—Blackburn Type 3‐Arylaminoimidazo[1,2‐a]azines Accessed via Pd‐Catalyzed Arylation of a Primary Precursor.
Authors: Sandulenko Yuri , Komarov Alexander , Rufanov Konstantin , Krasavin Mikhail
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Enantioselective Hydrogenation: Phospholane Ligands
Authors: Cobley Christopher J. , Moran Paul H.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Supercritical and Compressed Carbon Dioxide as Reaction Medium and Mass Separating Agent for Hydrogenation Reactions Using Organometallic Catalysts
Authors: Leitner Walter
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Synthesis of Natural Products Employing the SAMP/RAMP Hydrazone Methodology
Authors: Enders Dieter , Bettray Wolfgang
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Dendritic Macromolecules for Organic Light‐Emitting Diodes
Authors: Hwang Seok‐Ho , Moorefield Charles N. , Newkome George R.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.