bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Stress-controlled Erosion Apparatus for Studying Internal Erosion in Soils
Authors: Chang D. S. , Zhang L. M. 
Published: July 2011

AbstractSuffusion in soil involves selective erosion of fine particles within the matrix of coarse soil particles under seepage flow. Such loss of fine particles affects the hydraulic and mechanical behavior of the soil. In this study, a stress-controlled erosion apparatus was developed to investigate the initiation and development of suffusion under complex stress states and to study the effect of suffusion on soil stress-strain behavior. The apparatus allows independent control of hydraulic gradient and stress state. The hydraulic gradient is controlled using a water-head control method. The eroded soil and the outflow rate are measured using a soil collection system and a water collection system, respectively. The measurements can be used to study the erosion rate and variations in soil permeability during the erosion process. A series of erosion tests was conducted on a gap-graded soil under the same confining stress but different deviatoric stresses. The results show that the maximum erosion rate, the variations in soil permeability, and the total deformation of the soil specimen increase with the increase of deviatoric stress. After the loss of a significant amount of fine particles in the soil, the stress-strain behavior of the test soil changes from dilative behavior to contractive behavior.
Deflection Lag, Load Lag, and Time Lag of Buried Flexible Pipe
Authors: Howard Amster 
Published: July 2011

Abstract
The Iowa formula was published by Professor M. G. Spangler of Iowa State Univ. in 1941 to predict the deflection of buried flexible pipe. In the equation, he used the term “deflection lag” to describe the increase in flexible pipe defection after the maximum load was reached over the pipe. Unfortunately, the term is currently improperly used in ASTM, AWWA, and ASCE manuals and standards to reflect the increase in deflection starting the day the backfill is completed over the pipe, rather than when the maximum load occurs. The maximum load on a pipe is generally not attained until after 3–12 months after construction. The history of the deflection lag term and the use of the term “load lag” by Professor Spangler are explored. For the increase in pipe deflection following construction completion, the use of the term “time lag” should be used. A table of time lag values for use in estimating deflection is presented. The table is based on empirical data from field measurements.
Effects of Austenitizing Temperatures on Primary Structure Transformation in Cast High-Speed Steel of M2 Type Inoculated with Powder Additions of W and TiB2
Authors: Chaus Alexander S. , Boháčik Michal , Úradník Peter , Porubský Ján 
Published: July 2011

Abstract
The influence of heat treatment on the microstructure of AISI M2 type high-speed steels modified with powder additions of W and TiB2 was studied. The primary focus was on the effects of austenitizing temperatures on the prior austenite grain size and size distribution, volume fraction, and morphology of the eutectic carbides M2C, M6C, and MC, as well as the character of the secondary precipitation of carbides in the high-speed steels studied. It was shown that austenitizing significantly affects the changes in the chemical composition, morphology, size, and character of distribution of the eutectic carbides in the high-speed steels studied, as well as the volume fraction of retained austenite in the matrix and the prior austenite grain size. These changes in carbides seemed to be induced by a diffusion-induced redistribution of alloying elements between the steel matrix and the carbide phases due to their mutual interaction at high temperatures, which is accompanied by carbide decomposition, coagulation and dissolution and, as a consequence, saturation of the solid solution by alloying elements.
Detector Tube Method for Ammonia Compared to Ion Selective Electrode for Selected Class C and Class F Fly Ash
Authors: Butler Steven Roy 
Published: July 2011

Abstract
An investigation into the field tests used to test for ammonia in fly ash was conducted for comparison to the ASTM C311-07 ammonia determination by the ion selective electrode (ISE) test method. “Ammonia tube result” (ATR) refers to a Gastec tube reading on trapped gas over a slurried fly ash mixture that is correlated to the ISE results by linear regression. This paper contains the following: A comparison of the actual ammonia measurement in the lab by ISE and EPA Method 350.1. Testing was performed on the same samples and in duplicate as a confirmation. The statistical correlation of ASTM C-618–08a, class C fly ash by the ATR to the ASTM C311-07 test method is demonstrated which is comparable to the correlation with the EPA method. A discussion of the differences between the ATR and referenced analytical methods on both ASTM C 618 - 08a class C and class F fly ashes is presented. The effect of sodium hydroxide addition as a catalyst for the ammonia release was significant for both ASTM C-618–08a class C and class F fly ash but differences were noted and are presented.
Serum vaspin levels in hypothyroid patients
Authors: Çinar Neşe , Gülçelik Neşe Ersöz , Aydín Kadriye , Akín Şafak , Usman Aydan , Gürlek Alper 
Published: July 2011

ObjectiveTo elucidate the link between TSH and obesity, the relationship between TSH and adipocytokines were previously studied. Animal studies demonstrated a possible relationship between vaspin levels and thyroid functions. In this study, we aimed to investigate vaspin levels in hypothyroid states and its relationship with insulin resistance parameters in humans.DesignProspective observational study.MethodsWe enrolled 27 overt hypothyroid, 33 subclinical hypothyroid and 41 euthyroid patients. We measured the body mass index (BMI), fasting glucose, fasting insulin, homeostasis model assessment of insulin resistance index (HOMA-IR), lipid profile, TSH, free triiodothyronine, free thyroxine and vaspin levels. The change in vaspin levels in 12 overt hypothyroid patients after establishment of euthyroidism was analysed.ResultsAll groups were age-matched. Overt hypothyroid group had higher BMI values (P<0.05) than other groups. No significant difference was observed in insulin levels and HOMA-IR among the groups (P>0.05). Adjusted vaspin levels for BMI and age were similar among the groups. Mean vaspin levels in overt, subclinical and euthyroid patients were 1.20±1.17, 1.48±0.93 and 0.95±0.75 ng/ml respectively (P>0.05). There was no significant association between vaspin levels and BMI, fasting glucose, insulin and HOMA-IR (P>0.05). Establishing euthyroidism in hypothyroid patients did not result in a significant change in vaspin levels (before and after treatment, 1.35±1.06 and 1.25±0.68 ng/ml, respectively; P>0.05).ConclusionWe herein present novel data indicating vaspin levels are neither altered in overt and subclinical hypothyroidism nor have a relationship with features of insulin resistance in hypothyroid patients.
Circulating glucagon is associated with inflammatory mediators in metabolically compromised subjects
Authors: Ortega Francisco J , Moreno-Navarrete José M , Sabater Mónica , Ricart Wifredo , Frühbeck Gema , Fernández-Real José M 
Published: July 2011

BackgroundAcute phase mediators promote metabolic changes by modifying circulating hormones. However, there is virtually no data about the link between glucagon and inflammatory parameters in obesity-related chronic low-grade inflammation.Study designWe performed both cross-sectional and longitudinal (diet-induced weight loss) studies.MethodsCirculating glucagon concentrations (ELISA), parameters of glucose and lipid metabolism, interleukin 6 (IL6), and complement factor B (CFB) were analyzed in 316 subjects (250 men and 66 women). The effects of weight loss were investigated in an independent cohort of 20 subjects.ResultsCirculating glucagon significantly correlated with glucose (r=0.407,P<0.0001), HbAlc (r=0.426,P<0.0001), fasting triglycerides (r=0.356,P=0.001), and parameters of innate immune response system such as IL6 (r=0.342,P=0.050) and CFB (r=0.404,P=0.002) in obese subjects with altered glucose tolerance, but not in individuals with normal glucose tolerance (NGT). In obese and NGT subjects, glucagon was associated with fasting triglycerides (r=0.475,P=0.003) and CFB (r=0.624,P=0.001). In obese subjects, glucagon (P=0.019) and CFB (P=0.002) independently contributed to 26% of fasting triglyceride variance (P<0.0001) after controlling for the effects of age and fasting serum glucose concentration in multiple lineal regression models. Moreover, concomitant with fat mass, fasting triglycerides, and CFB, weight loss led to significantly decreased circulating glucagon (−23.1%,P=0.004).ConclusionsAccording to the current results, acute phase reactants such as IL6 and CFB are associated with fasting glucagon in metabolically compromised subjects. This suggests that glucagon may be behind the association between inflammatory and metabolic parameters in obesity-associated chronic low-grade inflammation.
Skeletal muscle mitochondrial function in polycystic ovarian syndrome
Authors: Rabøl Rasmus , Svendsen Pernille F , Skovbro Mette , Boushel Robert , Schjerling Peter , Nilas Lisbeth , Madsbad Sten , Dela Flemming 
Published: July 2011

ObjectivePolycystic ovarian syndrome (PCOS) is associated with skeletal muscle insulin resistance (IR), which has been linked to decreased mitochondrial function. We measured mitochondrial respiration in lean and obese women with and without PCOS using high-resolution respirometry.MethodsHyperinsulinemic–euglycemic clamps (40 mU/min per m2) and muscle biopsies were performed on 23 women with PCOS (nine lean (body mass index (BMI) <25 kg/m2) and 14 obese (BMI >25 kg/m2)) and 17 age- and weight-matched controls (six lean and 11 obese). Western blotting and high-resolution respirometry was used to determine mitochondrial function.ResultsInsulin sensitivity decreased with PCOS and increasing body weight. Mitochondrial respiration with substrates for complex I and complex I+II were similar in all groups, and PCOS was not associated with a decrease in mitochondrial content as measured by mitochondrial DNA/genomic DNA. We found no correlation between mitochondrial function and indices of insulin sensitivity.ConclusionsIn contrast to previous reports, we found no evidence that skeletal muscle mitochondrial respiration is reduced in skeletal muscle of women with PCOS compared with control subjects. Furthermore, mitochondrial content did not differ between our control and PCOS groups. These results question the causal relationship between reduced mitochondrial function and skeletal muscle IR in PCOS.
A Case Study of the Factors that Impact Horizontal Oil Well Production Performance in the Niger Delta
Authors: Thomas Ayoola Olakunle , Nigeria Shell 
Published: July 2011

Abstract
Various factors have an impact on the production performance of horizontal oil wells. Geological and reservoir factors such as environment of deposition and the thickness, permeability and reservoir drive mechanism, operational practices during the drilling of the horizontal drain hole such as the selection of the drill-in and completion fluids and the amount of overbalance pressure exerted on the production interval and technical design factors such as sand face completion types deployed and clean-up practice employed have significant impact on the production performance.
This study was conducted to assess the impact of the various factors on the production performance of horizontal wells through the comprehensive analysis of 70 horizontal oil wells in the Niger Delta. The wells were drilled and put on production over a period from 1993 to 2007.
The results from the study indicate that a combination of factors including shoreface facies type, minimum overbalance, oil-free mud system, brine completion fluid system, pre-drilled or slotted liner and clean up using nitrified hydrochloric acid circulated with coil tubing is required to optimise horizontal oil well production performance in the Niger Delta. Considerations of these factors when planning horizontal oil well development projects in the Niger Delta will ensure technical and operational excellence and improve overall project economics. Furthermore, the adaptation and application of the approach used in this study by the oil and gas industry worldwide will aid well performance monitoring under diverse technical and operational conditions and assist in optimal well design and performance optimisation.
Negative-pressure and low-pressure hydrocephalus: the role of cerebrospinal fluid leaks resulting from surgical approaches to the cranial base
Authors: Filippidis Aristotelis S. , Kalani M. Yashar S. , Nakaji Peter , Rekate Harold L. 
Published: July 2011

Object
Negative-pressure and low-pressure hydrocephalus are rare clinical entities that are frequently misdiagnosed. They are characterized by recurrent episodes of shunt failure because the intracranial pressure is lower than the opening pressure of the valve. In this report the authors discuss iatrogenic CSF leaks as a cause of low- or negative-pressure hydrocephalus after approaches to the cranial base.

Methods
The authors retrospectively reviewed cases of low-pressure or negative-pressure hydrocephalus presenting after cranial approaches complicated with a CSF leak at their institution.

Results
Three patients were identified. Symptoms of high intracranial pressure and ventriculomegaly were present, although the measured pressures were low or negative. A blocked communication between the ventricles and the subarachnoid space was documented in 2 of the cases and presumed in the third. Shunt revisions failed repeatedly. In all cases, temporary clinical and radiographic improvement resulted from external ventricular drainage at subatmospheric pressures. The CSF leaks were sealed and CSF communication was reestablished operatively. In 1 case, neck wrapping was used with temporary success.

Conclusions
Negative-pressure or low-pressure hydrocephalus associated with CSF leaks, especially after cranial base approaches, is difficult to treat. The solution often requires the utilization of subatmospheric external ventricular drains to establish a lower ventricular drainage pressure than the drainage pressure created in the subarachnoid space, where the pressure is artificially lowered by the CSF leak. Treatment involves correction of the CSF leak, neck wrapping to increase brain turgor and allow the pressure in the ventricles to rise to the level of the opening pressure of the valve, and reestablishing the CSF route.
Magnetic resonance imaging techniques for visualization of the subthalamic nucleus
Authors: Brunenberg Ellen J. L. , Platel Bram , Hofman Paul A. M. , ter Haar Romeny Bart M. , Visser-Vandewalle Veerle 
Published: July 2011

The authors reviewed 70 publications on MR imaging–based targeting techniques for identifying the subthalamic nucleus (STN) for deep brain stimulation in patients with Parkinson disease. Of these 70 publications, 33 presented quantitatively validated results.
There is still no consensus on which targeting technique to use for surgery planning; methods vary greatly between centers. Some groups apply indirect methods involving anatomical landmarks, or atlases incorporating anatomical or functional data. Others perform direct visualization on MR imaging, using T2-weighted spin echo or inversion recovery protocols.
The combined studies do not offer a straightforward conclusion on the best targeting protocol. Indirect methods are not patient specific, leading to varying results between cases. On the other hand, direct targeting on MR imaging suffers from lack of contrast within the subthalamic region, resulting in a poor delineation of the STN. These deficiencies result in a need for intraoperative adaptation of the original target based on test stimulation with or without microelectrode recording.
It is expected that future advances in MR imaging technology will lead to improvements in direct targeting. The use of new MR imaging modalities such as diffusion MR imaging might even lead to the specific identification of the different functional parts of the STN, such as the dorsolateral sensorimotor part, the target for deep brain stimulation.
Tumor origin and hearing preservation in vestibular schwannoma surgery
Authors: Rachinger Jens , Rampp Stefan , Prell Julian , Scheller Christian , Alfieri Alex , Strauss Christian 
Published: July 2011

Object
Preservation of cochlear nerve function in vestibular schwannoma (VS) removal is usually dependent on tumor size and preoperative hearing status. Tumor origin as an independent factor has not been systematically investigated.

Methods
A series of 90 patients with VSs, who underwent surgery via a suboccipitolateral route, was evaluated with respect to cochlear nerve function, tumor size, radiological findings, and intraoperatively confirmed tumor origin. All patients were reevaluated 12 months after surgery.

Results
Despite comparable preoperative cochlear nerve status and larger tumor sizes, hearing preservation was achieved in 42% of patients with tumor originating from the superior vestibular nerve, compared with 16% of those with tumor originating from the inferior vestibular nerve.

Conclusions
Tumor origin is an important prognostic factor for cochlear nerve preservation in VS surgery.
Serum Interleukin-6 Levels Correlate with Resistance to Treatment of Chronic Hepatitis C Infection with Pegylated-Interferon-α2B plus Ribavirin
Authors:   the Ochanomizu-Liver Conference Study Group, Ueyama Mayumi , Nakagawa Mina , Sakamoto Naoya , Onozuka Izumi , Funaoka Yusuke , Watanabe Takako , Nitta Sayuri , Kiyohashi Kei , Kitazume Akiko , Murakawa Miyako , Nishimura-Sakurai Yuki , Sekine-Osajima Yuko , Itsui Yasuhiro , Azuma Seishin , Kakinuma Sei , Watanabe Mamoru 
Published: July 2011

Background Interleukin (IL)-6, a pleiotropic cytokine, is increased in various types of chronic liver disease, including chronic hepatitis C (CHC). It was reported recently that IL-6 is associated with insulin resistance, iron metabolism and interferon resistance, which may affect the outcome of antiviral treatment. In this study, we investigated the association of serum IL-6 levels with outcomes of pegylated interferon (PEG-IFN) plus ribavirin (RBV) combination therapy. Methods We included 149 CHC patients and measured serum IL-6 levels at baseline and at 4, 8 and 12 weeks, and the end of treatment in 49 patients. We performed univariate and multivariate regression analyses for the association of IL-6 levels and clinical and laboratory parameters and treatment responses. Results Serum IL-6 levels were significantly higher in CHC patients than healthy subjects. Pretreatment IL-6 levels of male patients were inversely correlated with sustained virological response (SVR) in univariate analysis ( P=0.012). In male patients with SVR, serum IL-6 levels decreased significantly at 4 weeks of treatment ( P=0.029) and remained significantly lower than those of non-SVR patients after 4, 8 and 12 weeks of PEG-IFN plus RBV therapy. Conclusions Our results suggest that baseline levels of IL-6, as well as their decrease during treatment, are correlated to outcomes of PEG-IFN plus RBV therapy in male patients. Further analyses of IL-6 may provide new strategies for difficult-to-treat CHC patients and prevention of hepatocarcinogenesis.
Serum Interleukin (IL)-10 and IL-12 Levels and Il28B Gene Polymorphisms: Pretreatment Prediction of Treatment Failure in Chronic Hepatitis C
Authors: Umemura Takeji , Joshita Satoru , Yoneda Suguru , Katsuyama Yoshihiko , Ichijo Tetsuya , Matsumoto Akihiro , Yoshizawa Kaname , Ota Masao , Tanaka Eiji 
Published: July 2011

Background Both IL28B gene polymorphisms and serum levels of interleukin (IL)-10, IL-12p40 and IL-18 have been reported to affect the outcome of natural and pegylated interferon and ribavirin-treated HCV infection. Methods To clarify their association and predictive value in treatment outcome of genotype 1 HCV- infected patients, we measured pretreatment serum IL-10, IL-12p40 and IL-18 levels using multiplex assays and determined IL28B gene polymorphisms (rs 8099917) in 52 cases with chronic hepatitis C. Results High baseline levels of IL-10 ( P<0.001) and low levels of IL-12p40 ( P<0.001) were significantly associated with a non-virological response (NVR) in our cohort. The IL28B polymorphism was tested and TT, TG or GG genotypes were found in 60%, 38% and 2% of patients, respectively, with corresponding NVR rates of 10%, 60% and 100% ( P<0.001). Serum cytokine levels were significantly correlated with IL28B gene polymorphisms. When serum IL-10 levels were stratified at 5.0 pg/ml, NVR rates were 50% versus 0% ( P=0.004) for the TT genotype and 87% versus 0% ( P=0.001) for the TG or GG genotypes. Similarly, low IL-12p40 levels were associated with an NVR in patients with TG or GG genotypes ( P=0.006). In multivariate analysis, high IL-10, low IL-12p40 and IL28B TG or GG genotypes were independently associated with an NVR. Conclusions Serum IL-10 and IL-12p40 levels in combination with IL28B genotype, especially G-allele carriage, are strong predictive markers of an NVR to HCV treatment with pegylated interferon and ribavirin.
Simultaneous Bilateral Cataract Surgery With IOL Implantation in Children in Kenya
Authors: Gradin Dan , Mundia Daniel 
Published: July 2011

Purpose:
To investigate the cost implications, safety, and refractive outcomes of simultaneous bilateral cataract surgery (SBCS) with intraocular lens implantation in pediatric patients in a developing world setting.

Methods:
Children aged 3 months to 10 years with bilateral congenital or developmental cataracts who underwent surgery between January 1, 2007, and December 31, 2009, were eligible for inclusion in this retrospective study. Cost data were compared for simultaneous and sequential cases. Postoperative complications and refraction data were analyzed.

Results:

Ninety-six children (192 eyes) were included, 48 in the SBCS group and 48 in the sequential group. The mean age of the SBCS group and the sequential group was 3.4 and 4.7 years, respectively (
P
= .04). The total estimated surgical cost was $274 per child for SBCS and $344 for sequential surgery, a reduction of 20.3% for cases of SBCS. Fibrin formation of any amount occurred in 52 of 192 eyes (27.1%), 25 in the SBCS group and 27 in the sequential group (
P
= .75). Twenty-one eyes (10.9%) had additional surgery to remove visual axis obstruction, 14 in the SBCS group and 7 in the sequential group (
P
= .11). The incidence of early endophthalmitis in all cases of pediatric cataract surgery in an 11-year period was 0.16%. The incidence of anesthetic-related death during the same period was 0.11%.

Conclusion:
Bilateral simultaneous pediatric cataract surgery with intraocular lens implantation may be a safe alternative to sequential surgery, with advantages in cost reduction and no difference in sight-threatening complications.