bluuebunny/crossref_metadata_2025 huggingface dataset:
Solid-Expandable Liner System With Custom Composite Frac Plugs Enables Recovery of Lost Reserves in the Piceance Basin
Authors: Caplis Chris , Cameron John , Holte Darwin , Frazier Garrett
Published: May 2013

Casing-integrity failure, whether through parted casing, leaky collars, or some other issue, may result in less-effective stimulation work caused by abandonment of the plug-and-perforate method and/or completing through a frac liner. In more-extreme cases, it could result in lost reserves below the casing-failure point. Modern technology has provided a cost-effective solution to this problem.

In this case, the operator confirmed parted 4 1/2-in. production casing at 9,761 ft (Fig. 1) in their northern Piceance basin acreage. The operator would have to repair the parted casing to fracture the lower six zones of the well. The plug-and-perforate method for zonal isolation was required to effectively complete the 2,825-ft vertical pay interval. To complete the stimulation program, the goals were to repair the short section of damaged casing and restore pressure integrity to the well while maintaining a sufficient inner diameter (ID) to allow composite frac plugs to pass through the repair and set in the base casing's larger ID below the split. After a corrugated patch failed to provide casing integrity, the solution was a 3 1/2-in. single-joint solid-expandable system that was expanded downhole to cover and seal the parted 4 1/2-in. casing in conjunction with the use of custom-made composite frac plugs.

The 30-ft, 3 1/2-in. solid-expandable high-pressure/high-temperature (HP/HT) liner system was deployed and expanded in a single trip. This system provided the required pressure integrity to withstand the fracturing pressures needed in this area. The 3.261-in. drift ID of the expanded-solid liner allowed the operator to run custom 3.06-in.-outer-diameter (OD) composite frac plugs below the repaired section and successfully complete the well.

This installation was a success because the operator had essentially written off 63% of the well's reserves caused by the casing part occurring above a majority of the pay interval. The operator is now realizing full production from the entire well. Moreover, this single-joint solid-expandable liner technology coupled with the special drillable composite frac plugs can be used in any HP/HT formation to repair the common issue of damaged casing to allow plug-and-perforage completions to continue.
Pressure-Dependent Natural-Fracture Permeability in Shale and Its Effect on Shale-Gas Well Production
Authors: Cho Y.. , Apaydin O.G.. G. , Ozkan E..
Published: May 2013

This paper presents an investigation of the effect of pressure-dependent natural-fracture permeability on production from shale-gas wells. The motivation of the study is to provide data for the discussion of whether it is crucial to pump proppant into natural fractures in shale plays. Experiments have been conducted on Bakken-shale core samples to select appropriate correlations to represent fracture conductivity as a function of pressure (the actual characterization of fracture conductivity under stress for a specific formation is not an objective of the study). Correlations have been used in a flow model to demonstrate the potential impact of natural-fracture closure as pressure drops during production. Although the correlations indicate up to an 80% reduction in fracture permeability over practical ranges of pressure, the results of the flow model do not warrant the claims that fracture closing plays a significant role in the productivity losses of shale-gas wells. A history match of the performances of two wells in the Barnett and Haynesville formations also indicates that the effect of pressure-dependent natural-fracture permeability on shale-gas-well production is a function of the permeability of the matrix system. If the matrix system is too tight, then the retained permeability of the natural fractures may still be sufficient for the available volume of the fluid when the system pressure drops.
Approximate Analytical Solutions for CO2 Injectivity Into Saline Formations
Authors: Azizi Ehsan , Cinar Yildiray
Published: May 2013

This paper presents new analytical models to estimate the bottomhole pressure (BHP) of a vertical carbon dioxide (CO2) injection well in a radial, homogeneous, horizontal saline formation. The new models include the effects of multiphase flow, CO2 dissolution in formation brine, and near-well drying out on the BHP. CO2 is injected into the formation at a constant rate. The analytical solutions are presented for three types of formation outer boundary conditions: closed boundary, constant-pressure boundary, and infinite-acting formation. The sensitivity of BHP computations to gas relative permeability, retardation factors, and CO2 compressibility is examined. The predictive capability of the analytical models is tested by use of numerical reservoir simulations. The results show a good agreement between the analytical and numerical computations for all three boundary conditions. Variations in gas compressibility, retardation factors, and gas relative permeability in the drying-out zone are found to have moderate effects on BHP computations. It is demonstrated for several hypothetical but realistic cases that the new models can estimate CO2 injectivity reliably.
On the Liquid-Flow Analog To Evaluate Gas Wells Producing in Shales
Authors: Chen C.. , Raghavan R..
Published: May 2013

Drawing on links to the analog considered by Al-Hussainy et al. (1966), we present a corresponding analog to correlate solutions for a fractured well producing at a constant pressure. A solution in terms of the similarity transformation for the pressure distribution in a linear reservoir filled with a real gas provides the basis. This solution is particularly suited to demonstrate that anomalous results will be obtained when long linear-flow trends typical of shales produced through a horizontal well consisting of multiple, infinite-conductivity fractures are evaluated in classical terms. The basis for the liquid-flow analog is re-examined by considering 2D numerical solutions for a fractured well producing a gas reservoir at a constant pressure. A method to correlate the nonlinear solutions with the corresponding liquid-flow solutions for fractured wells producing at a constant pressure during the infinite-acting period is provided. The phrase “analog” used here represents attempts to match values of both the well response and its derivative for a 2D system during transient flow. This correlation enables analysts to obtain estimates that are accurate in the manner of Al-Hussainy et al. (1966). An example illustrates the application of this recommendation for a horizontal well producing a shale reservoir through multiple hydraulic fractures.
Phenotypic and Molecular Genetic Variation in Tunisian Natural Populations of Sulla carnosa
Authors: Neji Mohamed , Taamalli Wael , Smida Malek , Abdelly Chedly , Gandour Mhemmed
Published: May 2013

Sulla carnosa (Desf.) is a diploid (2n = 16), allogamous, seed‐propagated species and has a vegetative shoot system characterized by an orthotropic main stem bearing some lateral plageotropic shoots. It is of interest for rangeland revegetation and production. In this study, we analyzed the genetic diversity of five S. carnosa populations using 15 quantitative traits and nine random amplified polymorphic DNA primers. A total of 14 and 41% of the total genetic variation was found among the populations for molecular and phenotypic traits, respectively (Gst = 0.14 and Qst = 0.41). Despite the relatively high level of gene flow among populations (Nm = 3.1 or 0.065 individuals per generation), results showed a significant isolation by distance. Correlations between characters as well as with climatic region were established. The most significant positive correlations were found between features related to plant strength, while the most significant negative correlations were found between the flowering time and traits related to plant strength. When correlated to climatic region, plant height (r = –0.75, P = 0.000) and flowering date (r = –0.71, P = 0.000) showed the most significant estimates, indicating a gradual variation of these phenotypic traits. These results suggest a prominent role for natural selection in accounting for patterns of genetic differentiation of quantitative traits among natural populations of S. carnosa.
Visual Versus Marker‐Based Selection of Hybrid Progeny in Fertile × Fertile Beet and Carrot Crosses
Authors: Schaber Margaret A. , Goldman Irwin L.
Published: May 2013

Cytoplasmic‐genic male sterility systems (CMS) help control pollination in carrot and table beet breeding programs and hybrid seed production. A challenge common to these breeding programs is identification of F1 hybrid progeny in crosses where both parents carry normal (N) cytoplasm. Such fertile × fertile crosses often produce both F1 and selfed progeny, making identification of F1 hybrids difficult. Such identification has traditionally been accomplished in carrot and table beet by visually scoring roots using heterosis for size. However, if heterosis is lacking, misidentification can result in systematic errors in the breeding process. We sought to determine how effective visual selection of hybrid progeny is in the context of table beet and carrot breeding programs. We used amplified fragment length polymorphisms (AFLP) markers to genotype parents and progeny in a variety of fertile × fertile crosses. Progeny were also grown in the field and evaluated for hybridity based on visual selection using the phenotype of heterosis for size. Two of five fertile × fertile table beet crosses and three of five fertile × fertile carrot crosses showed highly significant differences between visual selection for hybridity and AFLP marker analysis (p < 0.01). Misidentification of roots as F1 hybrids when they were actually self‐pollinated occurred in some crosses as much as 75% of the time. Both type I, a hybrid root scored as an inbred, and type II, an inbred root scored as a hybrid, errors were committed. Across all matings, type I errors occurred on average 40.9% of the time and type II errors occurred on average 8.5% of the time. Type II errors have important consequences because both parents are not represented and recombined in the progeny resulting in further inbreeding. The results of this study indicate that using heterosis for size as a hybrid selection method can be inaccurate for identification of hybrids in certain crosses and may introduce error into breeding programs.
Effects of Soil and Foliar Application of Soluble Silicon on Mineral Nutrition, Gas Exchange, and Growth of Potato Plants
Authors: Pilon Cristiane , Soratto Rogério P. , Moreno Leticia A.
Published: May 2013

Silicon can alleviate biotic and abiotic stresses in several crops, and it has beneficial effects on plants under nonstressed conditions. However, there is still doubt about foliar‐applied Si efficiency and Si effects on mineral nutrition, physiological processes, and growth of potato (Solanum tuberosum L.) plants under well‐watered conditions. The objective of this study was to evaluate the effect of soil and foliar application of soluble Si on Si accumulation, nutrients, and pigments concentration as well as gas exchange and growth of potato plants. The experiment was conducted under greenhouse conditions in pots containing 35 dm3 of a Typic Acrortox soil. The treatments consisted of a control (no Si application), soil application of soluble Si (50 mg dm−3 Si), and foliar application of soluble Si (three sprays of 1.425 mM Si water solution, prepared with a soluble concentrate stabilized silicic acid), with eight replications. Both soil and foliar application of Si resulted in higher Si accumulation in the whole plant. Foliar application of Si resulted in the greatest Si concentration in leaves, and soil application increased Si concentration in leaves, stems, and roots. Silicon application, regardless of the application method, increased leaf area, specific leaf area, and pigment concentration (chlorophyll a and carotenoids) as well as photosynthesis and transpiration rates of well‐watered potato plants. However, only soil application increased P concentration in leaves and dry weight of leaves and stems.
Protein Expression Changes in Anther Callus of Ginseng during Low‐Temperature Acclimation
Authors: Lei Xiujuan , Wang Yingping , Li Changyu , Zhang Chengguo , Song Juan , Liu Lili , Bai Yongzhi
Published: May 2013

Low‐temperature acclimation is one of the main methods of improving the cryopreservation of anther callus of ginseng (Panax ginseng C. A. Mey.), particularly the callus survival rate. To investigate the molecular adaptation mechanisms of callus to low temperature, calli were induced from anthers and cultured at optimal temperature (25°C) for 15 d. Half of the calli were transferred to conditioned petri dishes stored at 4°C for different days. The optimal treatment time at 4°C was estimated based on the triphenyltetrazolium chloride value and survival rate of callus. Proteomic analysis showed that the abundance of 43 protein spots significantly changed (p < 0.5) under 4°C acclimation, and they were identified using mass spectrometry. The proteins were found to be involved in stress response and defense, carbohydrate metabolism, amino acid and protein biogenesis and degradation, molecular chaperone, electron transport coupled with adenosine triphosphate (ATP) synthesis, and cellular processes as well as nucleotide metabolism. The results suggested that the enhancement of stress response, organic metabolism, ATP synthesis, and molecular chaperoning played important roles in the adaptation of ginseng anther callus to low temperature.
An Aegilops ventricosa Translocation Confers Resistance Against Root‐knot Nematodes to Common Wheat
Authors: Williamson Valerie M. , Thomas Varghese , Ferris Howard , Dubcovsky Jorge
Published: May 2013

Root knot nematodes (RKN; Meloidogyne spp.) cause severe losses worldwide to a wide range of crops. Crop rotations with resistant hosts can be used to control losses, but the wide host range of RKN limits this option. In this study, we found that the wheat cultivar Lassik is resistant to several isolates of the RKN species M. incognita and M. javanica, including those that can reproduce on tomato with the resistance gene Mi‐1. Comparison of near‐isogenic lines of wheat showed that the wheat resistance gene(s) is localized within a segment of the short arm of chromosome 2N from Aegilops ventricosa (Zhuk.) Chennav translocated into common wheat (Triticum aestivum L.) chromosome arm 2AS and is associated with a highly significant decrease in RKN eggs in the roots. This RKN resistance gene has been assigned the name Rkn3. While wheat itself is tolerant of RKN infection, a microplot experiment coupled with tomato bioassays showed less RKN root galling in the tomato samples grown in soil from the previous microplots including RKN resistant wheat varieties than in those including a susceptible wheat isogenic line. This result suggests that rotation with Rkn3 resistant wheat cultivars has the potential to be a valuable component of nematode management for crops that are highly susceptible to nematode damage and for which alternative strategies are limited.
Partial Decomposition of the Genetic Correlation between Forage Yield and Fiber Using Semihybrids
Authors: Casler Michael D.
Published: May 2013

Voluntary intake potential of a forage crop is generally considered to be the most important feed characteristic regulating animal performance. Efforts to develop forage crops with increased intake potential have been associated with reduced plant fitness, prompting a need to modify breeding objectives and methods. The objective of this study was to determine if semihyrids could be used to restore all or a portion of the forage yield lost to drift during selection for low neutral detergent fiber (NDF) in smooth bromegrass (Bromus inermis Leyss.). A total of 48 semihybrids were created by pair crossing within four base (original) populations, four high‐NDF populations, and four low‐NDF populations. Genetic variation declined progressively with increased NDF concentration. Midparent heterosis was positive and significant for four of six semihybrids at the low‐NDF level. Two of these semihybrids also had positive and significant heterosis for NDF, reflecting the typical positive genetic correlation between yield and NDF. However, two of these semihybrids had no heterotic effect for NDF, resulting in partial decay of the genetic correlation due to a combination of linkage and drift acting on alleles that independently control these two traits. Because about one‐third of this genetic correlation is malleable by manipulation of linkage and drift, there is potential to produce low‐NDF smooth bromegrass populations without sacrificing forage yield potential.
Seasonal Changes and Treatment Effects on Soil Inorganic Nutrients Following a Decade of Fertilizer Addition in a Lowland Tropical Forest
Authors: Turner Benjamin L. , Yavitt Joseph B. , Harms Kyle E. , Garcia Milton N. , Romero Tania E. , Wright S. Joseph
Published: May 2013

We conducted monthly measurements of extractable soil nutrients, including N, P, base cations, and micronutrients, as well as the potential toxin Al, in a long‐term fertilization experiment in lowland tropical rain forest in the Republic of Panama. Our prediction was that the response of individual nutrients to seasonal climate and fertilizer addition would vary depending on the nature of their biogeochemical cycles. We detected significant seasonal variation in soil pH and all nutrients measured, although only extractable K concentrations were greater in the early wet season, while extractable phosphate varied little in plots that did not receive P addition. A decade of N addition increased soil nitrate, had no effect on extractable ammonium, and decreased soil pH (∼0.8 units in plots receiving only N). The decline in pH caused a corresponding decline in extractable base cations (Ca and K) and increased extractable Al, highlighting an important but poorly understood consequence of long‐term atmospheric N deposition onto tropical forests. A decade of P addition increased extractable phosphate by 50‐fold, indicating that chronic fertilizer addition has overcome the high phosphate sorption capacity of the soil. Potassium addition without N increased extractable soil K by 91%, but only by 25% when K was added in combination with N, suggesting that the previously reported N × K interactive effect on trunk growth rates could be a true response to N addition. Extractable Cu and Zn were increased twofold by micronutrient fertilizer addition, were reduced in the dry season, but were not affected by N addition (i.e., soil acidification). We conclude that the response of extractable nutrients to seasonal climate and fertilizer addition varies among nutrients, and suggest that greater attention be paid to the biological implications of acidification in response to long‐term atmospheric N deposition onto strongly‐weathered tropical forest soils.
Soil Water and Salinity Distribution under Different Treatments of Drip Irrigation
Authors: Selim Tarek , Bouksila Fethi , Berndtsson Ronny , Persson Magnus
Published: May 2013

In this study, field experiments and numerical simulations for different drip irrigation treatments in a sandy loam soil were conducted to investigate soil water and salinity distribution as well as dye infiltration patterns. Three treatments, surface drip irrigation without and with plastic mulch (T1 and T2, respectively) and subsurface drip irrigation (T3), were used. Daily and bi‐weekly irrigation regimes were used for each treatment. After completion of each irrigation treatment, horizontal soil sections were dug with 10 cm intervals. Dye patterns were photographed using a digital camera and soil water and pore water electric conductivity were measured by a WET‐sensor. Experimental results revealed that maximum dye infiltration depth and maximum dye coverage volume occurred during the bi‐weekly irrigation regime and in T3. Daily irrigation regime kept the top soil layer moist with adequate amount of soil water as compared to the bi‐weekly irrigation. Moreover, T2 provided higher soil water content within the soil domain as compared to other treatments. The simulation results demonstrated that model prediction for soil moisture distribution within the flow domain was excellent. Furthermore, T2 and daily irrigation showed lower salinity levels in the flow domain as compared to other irrigation treatments and regimes. In sum, mulching treatment with daily irrigation regime is recommended for arid areas over other drip irrigation treatments and regimes. In addition, HYDRUS‐2D/3D can be used as a fast and cost effective assessment tool for water flow and salt movement for sites having similar soil conditions.
A Soil Quality and Metabolic Activity Assessment after Fifty‐Seven Years of Agricultural Management
Authors: Stott Diane E. , Karlen Douglas L. , Cambardella Cynthia A. , Harmel R. Daren
Published: May 2013

Soil quality assessment is a process for understanding long‐term effects of soil and crop management. Our objective was to assess those effects on Vertisols in Texas after 57 yr. Five fields were sampled in 2006: a managed native pasture (NP), two pastures that were previously cropped and then seeded to Coastal bermudagrass [Cynodon dactylon (L.) Pers.] for the past 57 (CB) or 31 (CBTL) yr, and two fields that have been continuously cropped (RCTL and RC). The RCTL and CBTL fields have had turkey (Meleagris gallopavo) litter amendments. The soil quality assessment was conducted using the Soil Management Assessment Framework, using 10 measured soil attributes. There were significant differences in the overall soil quality ratings, which ranged from 75 to 94% of optimum in the following order: CBTL > NP = RCTL > CB ≈ RC. When separated into index values by sector, physical soil quality ranged from 66 to 84% of optimum, with NP ≈ CBTL > RCTL ≈ CB ≈ RC. All management systems had nearly the same chemical quality rating (94–95%). Focusing only on nutrient attributes, RC, RCTL, and CBTL had significantly higher ratings than the other treatments (99%), with NP being significantly lower (47%). Biological and biochemical soil quality ratings ranged from 44 to 81%, with the NP performing significantly better (81%) and RC significantly lower (44%) than the other treatments. The CBTL treatment exhibited the greatest levels of enzymatic activity and RC the lowest. There were several significant correlations between soil enzymatic activities and other soil parameters. Overall, turkey litter amendments improved soil quality, demonstrating that carefully managed bermudagrass pastures can be more productive than managed native grass pastures, primarily because of improved plant nutrient availability.
Disparities in Health, Poverty, Incarceration, and Social Justice among Racial Groups in the United States: A Critical Review of Evidence of Close Links with Neoliberalism
Authors: Nkansah-Amankra Stephen , Agbanu Samuel Kwami , Miller Reuben Jonathan
Published: May 2013

Problems of poverty, poor health, and incarceration are unevenly distributed among racial and ethnic minorities in the United States. We argue that this is due, in part, to the ascendance of United States-style neoliberalism, a prevailing political and economic doctrine that shapes social policy, including public health and anti-poverty intervention strategies. Public health research most often associates inequalities in health outcomes, poverty, and incarceration with individual and cultural risk factors. Contextual links to structural inequality and the neoliberal doctrine animating state-sanctioned interventions are given less attention. The interrelationships among these are not clear in the extant literature. Less is known about public health and incarceration. Thus, the authors describe the linkages between neoliberalism, public health, and criminal justice outcomes. We suggest that neoliberalism exacerbates racial disparities in health, poverty, and incarceration in the United States. We conclude by calling for a new direction in public health research that advances a pro-poor public health agenda to improve the general well-being of disadvantaged groups.
Neighborhood Adversity, Ethnic Diversity, and Weak Social Cohesion and Social Networks Predict High Rates of Maternal Depressive Symptoms: A Critical Realist Ecological Study in South Western Sydney, Australia
Authors: Eastwood John Graeme , Kemp Lynn Ann , Jalaludin Bin Badrudin , Phung Hai Ngoc
Published: May 2013

The aim of the study reported here is to explore ecological covariate and latent variable associations with perinatal depressive symptoms in South Western Sydney for the purpose of informing subsequent theory generation of perinatal context, depression, and the developmental origins of health and disease. Mothers (n = 15,389) delivering in 2002 and 2003 were assessed at two to three weeks after delivery for risk factors for depressive symptoms. The binary outcome variables were Edinburgh Postnatal Depression Scale (EPDS) > 9 and > 12. Aggregated EPDS > 9 was analyzed for 101 suburbs. Suburb-level variables were drawn from the 2001 Australian Census, New South Wales Crime Statistics, and aggregated individual-level risk factors. Analysis included exploratory factor analysis, univariate and multivariate likelihood, and Bayesian linear regression with conditional autoregressive components. The exploratory factor analysis identified six factors: neighborhood adversity, social cohesion, health behaviors, housing quality, social services, and support networks. Variables associated with neighborhood adversity, social cohesion, social networks, and ethnic diversity were consistently associated with aggregated depressive symptoms. The findings support the theoretical proposition that neighborhood adversity causes maternal psychological distress and depression within the context of social buffers including social networks, social cohesion, and social services.
The ‘Missing Heritability’ of Common Disorders: Should Health Researchers Care?
Authors: Chaufan Claudia , Joseph Jay
Published: May 2013

This article critiques the “missing heritability” position, which calls for greater efforts and funding to identify the genetic architecture of common disorders, even if this endeavor has yet to translate into tangible prevention, diagnosis, or treatment interventions. Supporters of the position contend that genetic variants “for” common disorders, which they argue must exist based on heritability estimates (hence their “missing heritability” position), have not been found because the current state of science and technology is not adequate to the task, yet they insist that this search warrants significant societal investments. We argue, instead, that these variants have not been found because they do not exist. The thrust of the problem with the “missing heritability” position, we propose, lies in its proponents' use of faulty concepts and research methods, including reliance on twin studies, plagued with environmental confounds; on the concept of heritability, a breeding statistic and not a measure of the importance of genetic influences on phenotypes; and on the belief that genetic variations are relevant to understanding, preventing, or treating common disorders, a belief that we argue is false. We elaborate on these problems, discuss their public health implications, and suggest future directions for a critical analysis of human genetics.
The Health of Safety Net Hospitals following Massachusetts Health Care Reform: Changes in Volume, Revenue, Costs, and Operating Margins from 2006 to 2009
Authors: Mohan Arun , Grant Jennifer , Batalden Maren , McCormick Danny
Published: May 2013

Massachusetts health care reform, designed to expand coverage and access to care for vulnerable populations, serves as the model for national health reform in the United States that will be implemented in 2014. Yet, little is known about how the reform may have affected the demand for and the financial performance of safety net hospitals (SNH), the primary source of care for such populations before the reform. Using a quasi-experimental design that included all acute care hospitals in the state, we calculated changes in mean inpatient and outpatient volumes, revenue, and operating margins at SNH from the pre-reform (Fiscal Year 2006) to the post-reform (Fiscal Year 2009) period. We contrasted these changes with contemporaneous changes occurring among non-safety net hospitals (NSNH) using a difference-in-differences approach. We found that SNH in Massachusetts continue to play a disproportionately large role in caring for disadvantaged patients after reform, but that their financial performance has declined considerably compared with NSNH. Ongoing reform efforts in the United States should account for continued SNH demand among the most vulnerable patients and should be designed so as not to undermine the financial stability of SNH that meet this demand.
Community Capacity as Means to Improved Health Practices and An End in Itself: Evidence from a Multi-Stage Study
Authors: Underwood Carol , Boulay Marc , Snetro-Plewman Gail , MacWan'gi Mubiana , Vijayaraghavan Janani , Namfukwe Mebelo , Marsh David
Published: May 2013

This three-phase study characterized, validated, and applied community capacity domains in a health communication project evaluation in Zambia. Phase I explored community capacity domains from community members' perspectives (16 focus groups, 14 in-depth interviews, 4 sites. These were validated in Phase II with 720 randomly selected adults. The validated domains were incorporated into a program evaluation survey (2,462 adult women, 2,354 adult men; October 2009). The results indicated that the intervention had direct effects on community capacity; enhanced capacity was then associated with having taken community action for health. Finally, community capacity mediated by community action and controlling for confounders, had a significant effect on women's contraceptive use, children's bed net use, and HIV testing. The results indicate that building community capacity served as a means to an end—improved health behaviors and reported collective action for health—and an end-in-itself, both of which are essential to overall wellbeing.
Out-of-Pocket Expenses for Maternity Care in Rural Bangladesh: A Public-Private Comparison
Authors: Rahman Md. Moshiur , Rob Ubaidur , Noor Forhana Rahman , Bellows Benjamin
Published: May 2013

Out-of-pocket expenses incurred by women for availing maternal healthcare services at public and private health facilities in Bangladesh were examined using a baseline household survey evaluating the impact of demand side financing vouchers on utilization and service delivery for maternal healthcare. The survey was conducted in 2010 among 3,300 women who gave birth in the previous 12 months from the start of data collection. Information on costs incurred to receive antenatal, delivery, and postnatal care services was collected. Findings reveal that the majority of women reported paying out-of-pocket expenses for availing maternal healthcare services both at public and private health facilities. Out-of-pocket expenses include registration, consultation, laboratory examination, medicine, transportation, and other associated costs incurred for receiving maternal healthcare services. On average, women paid US$3.60 out-of-pocket expenses for receiving antenatal care at public health facilities and US$12.40 at private health facilities. Similarly, women paid one and half times more for normal (US$42.30) and cesarean deliveries (US$136.20) at private health facilities compared to public health facilities. On the other hand, costs for postnatal care services did not vary significantly between public and private health facilities. Utilization of maternal healthcare services can be improved if out-of-pocket expenses can be minimized. At the same time, effective demand generation strategies are necessary to encourage women to utilize health facilities.
Temporal Trends in the Incidence, Treatment, and Outcomes of Hip Fracture in Older Patients Initiating Dialysis in the United States
Authors: Nair Sumi Sukumaran , Mitani Aya A. , Goldstein Benjamin A. , Chertow Glenn M. , Lowenberg David W. , Winkelmayer Wolfgang C.
Published: May 2013

Background and objectives

Patients with ESRD experience a fivefold higher incidence of hip fracture than the age- and sex-matched general population. Despite multiple changes in the treatment of CKD mineral bone disorder, little is known about long-term trends in hip fracture incidence, treatment patterns, and outcomes in patients on dialysis.

Design, setting, participants, & measurements

Fourteen annual cohorts (1996–2009) of older patients (≥67 years) initiating dialysis in the United States were studied. Eligible patients had Medicare fee-for-service coverage for ≥2 years before dialysis initiation and were followed for ≤3 years for a first hip fracture. Type of treatment (internal fixation or partial or total hip replacement) was ascertained along with 30-day mortality. Cox and modified Poisson regressions were used to describe trends in study outcomes.

Results

This study followed 409,040 patients over 607,059 person-years, during which time 17,887 hip fracture events were recorded (29.3 events/1000 person-years). Compared with patients incident for ESRD in 1996, adjusted hip fracture rates increased until the 2004 cohort (+41%) and declined thereafter. Surgical treatment included internal fixation in 56%, partial hip replacement in 29%, and total hip replacement in 2%, which remained essentially unchanged over time; 30-day mortality after hip fracture declined from 20% (1996) to 16% (2009).

Conclusions

Hip fracture incidence rates remain higher today than in patients reaching ESRD in 1996, despite multiple purported improvements in the management of CKD mineral bone disorder. Although recent declines in incidence and steady declines in associated short-term mortality are encouraging, hip fractures remain among the most common and consequential noncardiovascular complications of ESRD.
Prevention of Contrast-Induced AKI
Authors: Weisbord Steven D. , Gallagher Martin , Kaufman James , Cass Alan , Parikh Chirag R. , Chertow Glenn M. , Shunk Kendrick A. , McCullough Peter A. , Fine Michael J. , Mor Maria K. , Lew Robert A. , Huang Grant D. , Conner Todd A. , Brophy Mary T. , Lee Joanne , Soliva Susan , Palevsky Paul M.
Published: May 2013

Contrast-induced AKI (CI-AKI) is a common condition associated with serious, adverse outcomes. CI-AKI may be preventable because its risk factors are well characterized and the timing of renal insult is commonly known in advance. Intravenous (IV) fluids and N-acetylcysteine (NAC) are two of the most widely studied preventive measures for CI-AKI. Despite a multitude of clinical trials and meta-analyses, the most effective type of IV fluid (sodium bicarbonate versus sodium chloride) and the benefit of NAC remain unclear. Careful review of published trials of these interventions reveals design limitations that contributed to their inconclusive findings. Such design limitations include the enrollment of small numbers of patients, increasing the risk for type I and type II statistical errors; the use of surrogate primary endpoints defined by small increments in serum creatinine, which are associated with, but not necessarily causally related to serious, adverse, patient-centered outcomes; and the inclusion of low-risk patients with intact baseline kidney function, yielding low event rates and reduced generalizability to a higher-risk population. The Prevention of Serious Adverse Events following Angiography (PRESERVE) trial is a randomized, double-blind, multicenter trial that will enroll 8680 high-risk patients undergoing coronary or noncoronary angiography to compare the effectiveness of IV isotonic sodium bicarbonate versus IV isotonic sodium chloride and oral NAC versus oral placebo for the prevention of serious, adverse outcomes associated with CI-AKI. This article discusses key methodological issues of past trials investigating IV fluids and NAC and how they informed the design of the PRESERVE trial.
Biological and productive properties of the forms of grapevine cultivar Traminer in the subregion of Nis
Authors: Cirkovic Bratislav , Zunic Dragoljub , Garic Mladjan , Cirkovic Dusica , Matijasevic Sasa , Jovanovic Zoran
Published: May 2013

Traminer is a well-known grapevine cultivar. It is thought to originate from
Tramin, Italy, wherefrom it has been introduced to many European countries
(France, Switzerland, Austria, Germany). Researches included two Traminer
cultivar forms: White Traminer and Red Traminer. Examinations were carried
out in a collection vineyard of the Viticulture and Wine Production Center of
Nis. The collection vineyard was planted in 1995, with planting space of 3 x
1.2 m. Examinations took three years (2004-2006) and encompassed phenological
observations, fertility, vegetative potential of a vine, resistance to
Botrytis cinerea and wine quality. A detailed ampelographic description of
two Traminer cultivar forms was also provided according to O.I.V.
descriptors. The purpose of this paper is to determine growth, fertility,
yield, and grape and wine quality of the examined Traminer cultivar forms in
the viticultural subregion of Nis. According to the results obtained, the
examined forms could be successfully grown in this region. Average grape
yield varied depending on conditions of the particular year. White Traminer
recorded higher yield, while Red Traminer recorded better quality. In
addition, the best vines have been selected within the forms, and they will
be used in further studies and multiplication.
Effect of a Neem preparation on reproduction of the nematode Globodera rostochiensis and growth of potato
Authors: Trifonova Zlatka
Published: May 2013

An experiment was conducted under glasshouse conditions to test the effects
of neem-based product in the form of drenches and potato tuber treatments on
the growth of potato and population density of the potato cyst nematode
Globodera rostochiensis. The soil applications of the biopreparation improved
the plant growth and yield of potato, being greatest with 1% Neem Azal. The
biggest increase in the yield occurred in the Oxamyl application (15.8%). The
biopreparation in concentrations from 0.2% to 1% increased the yield of
potatoes from 0.3% to 9.7% compared to the untreated inoculated control. The
soil application was relatively more effective in increasing of the yield
(0.3%-9.7%) than the potato tuber treatments (0.3%-2.3%). The nematode
reproduction was reduced 83.3% with Oxamyl and from 59.8% to 71.0% with Neem
Azal treatments.
Transition metals in ZnO nanocrystals: Magnetic and structural properties
Authors: Kuryliszyn-Kudelska I. , Dobrowolski W. , Arciszewska M. , Romcevic N. , Romcevic M. , Hadzic B. , Sibera D. , Narkiewicz U. , Lojkowski W.
Published: May 2013

Currently, wide-gap ZnO nanoparticles bear important potential application in
electro-optical devices, transparent ultraviolet protection films, and
spintronic devices. We have studied the magnetic properties of nanocrystals
of ZnO(Fe, Co, Mn) prepared by two methods of synthesis. We have used the
microwave assisted hydrothermal synthesis and traditional wet chemistry
method followed by calcination. The detailed structural characterization was
performed by means of X-ray diffraction and micro-Raman spectroscopy
measurements. The morphology of the samples was studied by means of SEM and
TEM microscopy. The results of systematic measurements of AC magnetic
susceptibility as a function of temperature and frequency as well as SQUID
magnetization are presented. The SQUID magnetization measurements revealed a
clear bifurcation of the FC and ZFC plots. Such behavior suggested
superparamagnetic behavior above the blocking temperature. The dynamic
magnetic measurements were performed at small AC magnetic field with
amplitude not exceeding 5 Oe and different frequency values (from 7 Hz to
9970 Hz). For ZnO(Fe) and ZnO(Mn), the AC susceptibility maxima has been
found for in-phase susceptibility Re(?) and for out of phase susceptibility
Im(?). We analyzed the observed frequency dependence of the peak temperature
in the AC susceptibility curve using the empirical parameter ? that is a
quantitative measure of the frequency shift and is given by the relative
shift of the peak temperature per decade shift in frequency, as well as
Vogel- Fulcher law. We observed two different types of magnetic behavior,
spin-glasslike behavior or superparamagnetic behavior, depending on the
synthesis process. For ZnO(Co) nanocrystalline samples high temperature
Curie-Weiss behavior in AC magnetic susceptibility was observed. We observed
that the determined negative values of the Curie- Weiss temperature ? depend
strongly on the nominal content of cobalt oxide. It was shown that for
calcination method the values of ? increase with the increase of magnetic ion
content indicating enhancement of predominance of antiferromagnetic
interactions. For hydrothermal method the opposite effect was observed
indicating the breakdown of predominance of aniferromagnetic coupling with
the increase of nominal magnetic ion content. This paper gives an in-depth
discussion of the structural and magnetic properties of ZnO nanocrystals in
addition to the technological issues such as different methods of wet
chemical synthesis.
Segregation analysis of mandibular prognathism in Korean orthognathic surgery patients and their families
Authors: Ko Jeong-Min , Suh Young Ju , Hong Jongrak , Paeng Jun-Young , Baek Seung-Hak , Kim Young Ho
Published: May 2013

Objective:

To investigate the existence of genetic influences on the incidence of mandibular prognathism (MP) in Korean Class III patients.

Materials and Methods:

The probands consisted of 100 Class III patients with MP (51 men and 49 women; mean age, 22.1 ± 5.2 years; SNA, 81.2° ± 3.2°; SNB, 84.1° ± 3.9°) who underwent orthognathic surgery. Using three-generation pedigree charts, questionnaires, and clinical examinations, general information and information regarding MP for a total of 3777 relatives of the probands (1911 men and 1866 women) was ascertained. Familial correlations of MP between possible pairs in the pedigree were estimated. Heritability (h2) of MP under various models was estimated. Segregation analysis was conducted under the assumption of the nonpolygenic multivariate logistic model and finite polygenic mixed model. One-, two-, and three-susceptibility-type models were evaluated.

Results:

Among 3777 relatives, 199 (97 men and 102 women) were affected with MP (5.3%). Correlation coefficients of MP incidence in full siblings and in parent-offspring were .2003 and .2036, respectively (all P < .001). The h2 of MP was estimated as 21.5% after adjusting for sex and founder effects. Two- and three–susceptibility-type models showed that the general model fit better than the other models. MP incidence did not have a major gene transmission model and was influenced by numerous minor effect genes and their additive effects.

Conclusion:

These results suggest that the inherited susceptibility to MP in Korean Class III patients might be due to the summation of minor effects from a variety of different genes and/or influence of environmental factors, rather than Mendelian transmission of major genes.
Concurrent Validity of the Modified International Physical Activity Questionnaire for French Obese Adolescents
Authors: Vanhelst Jérémy , Fardy Paul S. , Mikulovic Jacques , Bui-Xuan Gilles , Béghin Laurent
Published: May 2013

Physical activity is an important component of a healthy lifestyle. Evaluating and promoting this activity warrants careful attention, particularly in the context of preventing obesity associated with low physical activity. The aim of the present study was to assess the concurrent validity of a modified, long, self-administered version of the International Physical Activity Questionnaire (IPAQ) using triaxial accelerometry in 56 youth with obesity. The participants' physical activity was measured with an RT3 accelerometer (objective measure) and with the International Physical Activity Questionnaire for Adolescents (IPAQ–A; subjective measure). Although the two methods were correlated strongly ( r = .84), there was a significant difference between the two methods. The participants' subjective ratings on the IPAQ–A overestimated the objective measure. Although activity questionnaires are simple and widely used in assessing physical activity, alternative methods should be used when measuring physical activity in youth with obesity.
Discriminatory Power of Game-Related Statistics in 14–15 Year Age Group Male Volleyball, According to Set
Authors: García-Hermoso Antonio , Dávila-Romero Carlos , Saavedra Jose M.
Published: May 2013

This study compared volleyball game-related statistics by outcome (winners and losers of sets) and set number (total, initial, and last) to identify characteristics that discriminated game performance. Game-related statistics from 314 sets (44 matches) played by teams of male 14- to 15-year-olds in a regional volleyball championship were analysed (2011). Differences between contexts (winning or losing teams) and “set number” (total, initial, and last) were assessed. A discriminant analysis was then performed according to outcome (winners and losers of sets) and “set number” (total, initial, and last). The results showed differences (winning or losing sets) in several variables of Complexes I (attack point and error reception) and II (serve and aces). Game-related statistics which discriminate performance in the sets index the serve, positive reception, and attack point. The predictors of performance at these ages when players are still learning could help coaches plan their training.
Fostering Revision of Argumentative Writing through Structured Peer Assessment
Authors: Tsai Ya-Chin , Chuang Min-Tun
Published: May 2013

This quasi-experimental study investigated the effect of structured peer assessment on revision of an argumentative writing. Two intact classes ( N = 22, 26) were randomly assigned to be the trained and control groups. The latter received no facultative resources, while the former participated in structured peer assessment based on Calibrated Peer Review™, a web-based program purposefully designed for students to receive peer-assessment training, assess their peers' writing, and make written commentary online. At the end of the treatment, both groups revised their writing. The trained group revised their writing more extensively, outperforming the control group on frequency and type of revision, as well as the holistic quality of argumentative writing. After structured peer assessment, participants of the trained group became critical of their own work and invested more effort in spontaneous revision to produce higher-quality argumentative writing.
Information and Repetition Change Children's Visual Strategies When Viewing Magic Tricks with and without Gaze Cues
Authors: Ordqvist Anna , Parsons Richard , Leung Denise , Dahlman Joakim , Falkmer Marita , Fleischer Håkan , Girdler Sonya , Falkmer Torbjörn
Published: May 2013

Gaze cues and direct gaze attract visual attention. However, few studies have explored visual cues in children within realistic contexts. The effect of information and repetitive stimulus presentation has not been thoroughly studied with dynamic stimuli. The aim of the present study was to investigate how information affects the visual strategies of children measured by the number of fixations on certain areas of interest and their durations. Furthermore, this study examined the effect of gaze cues and direct gaze. In two consecutive experiments, children's visual strategies when viewing magic tricks were measured by an eye tracker. Gaze cues were only present in Experiment 1. The results showed that repetitive stimulus presentation and information caused children to change their visual strategies when viewing magic tricks with and without gaze cues. However, the effect was larger when the gaze cues were not present. These findings in children were similar to those in adults.