bluuebunny/crossref_metadata_2025_split huggingface dataset:
Management of major bile duct injury after laparoscopic cholecystectomy: a case report
Authors: Manouras Andreas , Pararas Nikolaos , Antonakis Pantelis , Lagoudiannakis Emannuel E , Papageorgiou George , Dalianoudis Ioannis G , Konstadoulakis Manoussos M 
Published: January 2009

Abstract

Introduction
Bile duct injury is a severe and potentially life-threatening complication of laparoscopic cholecystectomy. Several series have described a 0.5% to 0.6% incidence of bile duct injury during laparoscopic cholecystectomy. The aim of this study was to analyze the presentation, characteristics, related investigation, and treatment results of major bile duct injuries after laparoscopic cholecystectomy.

Case presentation
A rare case of a 48-year-old Greek woman with a triple bile duct injury (right and left hepatic duct ligation and common bile duct cross-section) is presented. A Roux en Y hepaticojejunostomy was performed after repeated endoscopic retrograde cholangiopancreatographies, percutaneous transhepatic catheterization of the ducts and magnetic resonance cholangiographies to delineate the biliary anatomy and assess the level of injury.

Conclusion
Early recognition and an adequate multidisciplinary approach are the cornerstones for the optimal final outcome. Suboptimal management of injuries often leads to more extensive damage to the biliary tree and its vasculature. Early referral to a tertiary care center with experienced hepatobiliary surgeons and skilled interventional radiologists would appear to be necessary to assure optimal results.
Influence of brain-derived neurotrophic factor on pathfinding of dentate granule cell axons, the hippocampal mossy fibers
Authors: Tamura Makoto , Tamura Naohiro , Ikeda Takamitsu , Koyama Ryuta , Ikegaya Yuji , Matsuki Norio , Yamada Maki K 
Published: January 2009

Abstract
Mossy fibers, the dentate granule cell axons, are generated throughout an animal's lifetime. Mossy fiber paths and synapses are primarily restricted to the stratum lucidum within the CA3 region. Brain-derived neurotrophic factor (BDNF), a neurotrophin family protein that activates Trk neurotrophin receptors, is highly expressed in the stratum lucidum in an activity-dependent manner. The addition of a Trk neurotrophin receptor inhibitor, K252a, to cultured hippocampal slices induced aberrant extension of mossy fibers into ectopic regions. BDNF overexpression in granule cells ameliorated the mossy fiber pathway abnormalities caused by a submaximal dose of K252a. A similar rescue was observed when BDNF was expressed in CA3 pyramidal cells, most notably in mossy fibers distal to the expression site. These findings are the first to clarify the role of BDNF in mossy fiber pathfinding, not as an attractant cue but as a regulator, possibly acting in a paracrine manner. This effect of BDNF may be as a signal for new fibers to fasciculate and extend further to form synapses with neurons that are far from active BDNF-expressing synapses. This mechanism would ensure the emergence of new independent dentate gyrus-CA3 circuits by the axons of new-born granule cells.
The generation and properties of human macrophage populations from hemopoietic stem cells
Authors: Way Kerrie J , Dinh Hang , Keene Martin R , White Kirby E , Clanchy Felix I L , Lusby Patricia , Roiniotis John , Cook Andrew D , Cassady A Ian , Curtis David J , Hamilton John A 
Published: January 2009

AbstractInformation about the development and function of human macrophage lineage populations, such as osteoclasts, is limited because of the lack of defined in vitro systems for their large-scale generation. Two M-CSF-containing cytokine cocktails were found under serum-free conditions to expand dramatically and to differentiate over time human CD34+ hemopoietic stem cells into nonadherent and adherent macrophage populations. These populations exhibited increasing degrees of maturity over a 3-week period characterized by morphology, surface marker expression (CD11b, CD86, CD64, CD14, and c-Fms), phagocytic function, and gene-expression profiling using quantitative PCR and microarray analysis (principal component analysis, k-means clustering, and gene ontology classification). As assessed by the last criterion, the adherent population obtained at 3 weeks from the one protocol tested had high similarity to the well-studied peripheral blood monocyte-derived macrophages. The one population tested could be induced to differentiate into osteoclasts in the presence of M-CSF and receptor activator of NF-κB ligand, as judged by morphology, gene expression, and bone-resorbing ability. In addition to the large numbers of macrophage lineage cells able to be produced, this replicating system may be suitable for the molecular analysis of macrophage lineage commitment and progression and for gene targeting and delivery.
A Convenient LC-MS Method for Assessment of Glucose Kinetics In Vivo with d-[13C6]Glucose as a Tracer
Authors: Zhang Haoyue , Stevens Robert D , Young Sarah P , Surwit Richard , Georgiades Anastasia , Boston Raymond , Millington David S 
Published: January 2009

Abstract
Background: The isotope-labeled intravenous glucose tolerance test (IVGTT) combined with computer modeling is widely used to derive parameters related to glucose metabolism in vivo. Most of these methods involve use of either 2H2-labeled or 13C1-labeled d-glucose as a tracer with GC-MS to measure the isotope enrichment. These methods are challenging, both technologically and economically. We have developed a novel approach that is suitable for labeled-IVGTT studies involving a large cohort of individuals.
Methods: The tracer, d-[13C6]glucose, is a low-cost alternative with the significant advantage that the sixth isotope of natural glucose has virtually zero natural abundance, which facilitates isotopomer analysis with &lt;1% labeled glucose in the infusate. After deproteinization of plasma samples collected at various times, glucose is converted to a stable derivative, purified by solid-phase extraction (SPE), and analyzed by HPLC–electrospray ionization mass spectrometry to accumulate the isotope-abundance data for the A+2, A+3, and A+6 ions of the glucose derivative. A 2-pool modeling program was used to derive standard kinetic parameters.
Results: With labeled-IVGTT data from 10 healthy male individuals, the values for insulin sensitivity, glucose effectiveness, and the plasma clearance rate estimated with the 2-pool minimal model compared well with values obtained via traditional methods.
Conclusions: The relative simplicity and robustness of the new method permit the preparation and analysis of up to 48 samples/day, a throughput equivalent to 2 complete IVGTT experiments, and this method is readily adaptable to existing 96 well–format purification and analytical systems.
An Empirical Relationship for Determining Shear Wave Velocity in Granular Materials Accounting for Grain Morphology
Authors: Patel A. , Bartake P. P. , Singh D. N. 
Published: January 2009

Abstract
It is well recognized that shear wave velocity in the soil mainly depends on its type, state of compaction, and the confining stress. However, the influence of other geometrical parameters of soil particles (such as size, shape, roundness, and sphericity) on the shear wave velocity has not received much attention of the earlier researchers. It must be noted that these parameters primarily control the delegation of the applied normal stress in the soil and hence would directly influence the magnitude of shear wave velocity in it. With this in view, investigations were conducted to determine shear wave velocity in different types of granular materials (sands, glass beads, and cenospheres) by employing bender elements. Details of the methodology adopted for this purpose are presented in this paper. Experimental data have been used to develop an empirical correlation predicting shear wave velocity in granular materials by inputting their mean grain size and shape, and the confining stress, under dry and saturated states. The utility and efficiency of these relationships has also been demonstrated.
An In Situ Test Method for Evaluating the Coupled Pore Pressure Generation and Nonlinear Shear Modulus Behavior of Liquefiable Soils
Authors: Cox Brady R. , Stokoe Kenneth H. , Rathje Ellen M. 
Published: January 2009

Abstract
An in situ test method for evaluating the coupled response between excess pore water pressure generation and nonlinear shear modulus behavior has been developed. This technique is an active, strain-based method that may be used to directly evaluate the liquefaction resistance of soils in place. The test is based on the premise of dynamically loading a native soil deposit in a manner similar to an earthquake while simultaneously measuring its response with push-in sensors. Dynamic loading is performed via a large, buggy-mounted hydraulic shaker (vibroseis) that is used to generate vertically propagating (downward), horizontally polarized shear waves (Svh-waves) of varying amplitude within an instrumented portion of a liquefiable soil deposit. The newly-developed, push-in sensors consist of a three-component (3D) MEMS accelerometer and a miniature pore water pressure transducer. The new test method has been used to conduct field experiments in liquefiable soil deposits approximately 3 to 4 m below the ground surface. These tests were successful at measuring: (1) excess pore water pressure generation, and (2) nonlinear shear modulus behavior in native silty-sand deposits as a function of induced cyclic shear strain and number of loading cycles. These accomplishments represent a large step forward in the ability to accurately evaluate the susceptibility of a soil deposit to earthquake-induced liquefaction. While typical test results are presented herein, this paper primarily focuses on the equipment, field testing practices, and data analysis procedures for the new test method.
Determination of Shrinkage Limit of Fine-Grained Soils by Wax Method
Authors: Prakash K. , Sridharan A. , Baba J. Ananth , Thejas H. K. 
Published: January 2009

Abstract
Shrinkage limit of fine-grained soils is one of the parameters that is used for predicting the volume stability of soils in the field. ASTM Standard D427-04 (2007) involves the use of mercury, a health hazardous substance. Many stringent precautionary safety and disposal measures have to be exercised before its use in the laboratory. The present technical note presents the wax method of determining the shrinkage limit of soil in the laboratory which does not require the use of mercury, and also to substantiate the method proposed by the ASTM standard. It involves the use of wax as a coating on the dry soil pat and the water displacement method for the determination of the dry volume of soil pat. The experimental results have shown that the values of shrinkage limit of soils determined by the wax method and by the mercury displacement method are within certain statistical bounds.
A Discussion of the Benefits and Problems of ASTM C 1324 for Analyzing Hardened Masonry Mortars
Authors: Powers Laura , Coleman Ann , Papas Susanne 
Published: January 2009

Abstract
Laboratory testing of mortars by chemical analysis and petrography is generally appropriate to determine mortar composition, and to provide a basis for the formulation of compatible repair or replacement mortars. In cases of masonry distress and failures, analysis by C 1324 alone is often less useful unless the laboratory work is guided by knowledge obtained in the field. In addition to requiring the technical skills of experienced chemists and petrographers, the application of C 1324 requires knowledge of the specifications for mortar for unit masonry and benefits from the knowledge of how mortars are prepared and installed.
The quality of the sampling for laboratory tests, the physical condition of the samples obtained, and the mortar constituents can all influence the reliability of the results obtained by the chemical analysis and the petrographic examination. We review the development of the standard, discuss related standards, and present our experience with modern mortars prepared in the field and tested in the laboratory in accordance with ASTM C 1324 to provide insight into the results and limitations of such analysis.
Evaluation of ASTM Methods to Determine Splitting Tensile Strength in Concrete, Masonry, and Autoclaved Aerated Concrete
Authors: Parker Cody K. , Tanner Jennifer E. , Varela Jorge L. 
Published: January 2009

Abstract
Tensile strength of concrete or masonry is a fundamental material characteristic used to predict crack formation. ASTM C 496 and C 1006 are specifically designed to determine the splitting tensile strength of concrete cylinders and masonry units, respectively. Finite element studies for the above tests were completed with the maximum tensile strength compared to the theoretical value in the corresponding ASTM equations. The objectives of this paper are as follows: (1) evaluate current ASTM test methods to determine splitting tensile strength using finite element analysis; (2) evaluate the splitting tensile strength of masonry assemblages through modifying an existing ASTM test; (3) evaluate the application of ASTM test methods to determine the splitting tensile strength of autoclaved aerated concrete; and (4) evaluate a proposed ASTM test to evaluate the splitting tensile strength of thin-bed mortar used in AAC construction. A case study of the splitting tensile strength of autoclaved aerated concrete is used to propose a single test method for this new material.
Type S Portland Cement-Lime Mortar as a Low-Lift Grout
Authors: Biggs David T. , Thomson Margaret L. 
Published: January 2009

Abstract
Specification for Grout for Masonry, ASTM C 476, allows grouts to be specified by a proportion method using the cementitious materials of portland cement, blended cement, hydrated or putty lime (with a 1/10 by volume limit), and aggregate. There is no limitation on slump values in ASTM but industry standards recommend a slump of 8 to 11 in. (203 to 279 mm). A second method of specifying grout is by its properties with a minimum 28-day compressive strength value of 2000 psi (13 790 kPa). It is not an uncommon practice, however, for masonry contractors to use portland cement-lime mortars in low-lift (less than 5 ft [1.52 m] height) applications at a consistency of bedding mortar or a pourable consistency. According to ASTM C 476, this application would neither meet the proportion specification because of too much lime nor the property specification because of too low a slump. This study, investigating the comparative compressive strength properties and reinforcement pull-out strength of Type S and Type N ASTM C 270 proportioned cement-lime mortars, ASTM C 476 grout, and grout with comparable hydrated lime proportions to a Type S mortar, supports the following conclusions: • Type S portland cement-lime mortar at a bedding mortar consistency will perform as grout in specific low-lift grouting applications. • Type S portland cement-lime mortar at a pourable consistency will perform as grout in specific low-lift grouting applications. • Type M portland cement-lime mortar at a bedding mortar consistency or pourable consistency could also be used as grout in specific low-lift grouting applications.
Modeling the Heat, Air, and Moisture Response of Building Envelopes: What Material Properties are Needed, How Trustful Are the Predictions?
Authors: Hens Hugo S. L. C. 
Published: January 2009

Abstract
The physical models which form the basis for the different software tools used to predict heat, air, and moisture response of building envelopes seem quite diverse. For example, various “potentials” are used, and each individual potential demands apparently different properties. Anyhow, when digging into the physics and confronting the theory with what is measurable, then an array of eight basic material characteristics appear, all backed by an experimental rationale. Adapting that array to the potentials in use is not a question of creating new properties but of implementing the basic ones into potential-adapted expressions. A different problem, however, is that these basic properties are macroscopic in nature, i.e., represent the complexity of a material at the micro-scale by one single “average” number. That introduces restrictions as to the use of the property values measured experimentally. Hence, those restrictions are typically mixed up with the inability of the actual software packages to represent reality in full detail. Too many times, assumed incorrectness of the property values are blamed for causing the differences found between the predicted and real heat, air, moisture response of envelope parts. That inability, instead, should convince researchers and building engineers that the way to gain a well balanced understanding of the heat, air, and moisture response of envelopes is not by modeling only but by combining modeling with testing and field experience.
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part III: Experimental Crack Growth Behavior
Authors: Olsen Kirk W. , Rimnac Clare M. 
Published: January 2009

Abstract
Because fatigue crack growth in a threaded fastener can cause the loss of an aircraft, damage tolerant analyses are required. Because designers commonly perform crack growth analyses on stainless steel fasteners with scant data or simplifying assumptions, or both, the objective of this research was to determine the stress intensity multiplication factor (Y) in the threads of a nut loaded, stainless steel, aerospace, roll-threaded bolt under tensile fatigue conditions as the nondimensionalized crack depth (a/d) approaches zero. Y(a/d) can then be used to improve the accuracy of fatigue crack growth life estimations. Unflawed and flawed aerospace bolts were fatigue tested at a maximum stress (S) ranging from the ultimate tensile strength (UTS) to the surface endurance limit of the test bolt and at several loading ratios of 0.1⩽R⩽0.9. Data collection from the fracture surfaces yielded crack front shape characterization and striation spacing. The shape of the crack front in the unflawed and flawed test bolts was different and both changed as the crack grew. Fifty-one striation spacing measurements ranging from 5.6×10−5 to 7.9×10−4 mm were found at crack depths of a/d&gt;0.035. These striation measurements were directly related to crack growth rates so that stress intensity factor ranges (ΔK) and in turn Y(a/d) could be estimated.
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part II: Material/Stress State and Bolt Strength
Authors: Olsen Kirk W. , Rimnac Clare M. , Ferrell Douglas W. , Garrett Carl E. 
Published: January 2009

Abstract
Because fatigue failure in a threaded fastener can cause the loss of an aircraft, fatigue strength analyses are required. Understanding the material and stress state within the threads of the bolt was one objective of this research because this information would provide insight into the cyclic strength of the bolt. The second objective was to determine the fatigue strength in the threads of a nut-loaded, stainless steel, aerospace, roll-threaded bolt under tensile fatigue conditions. The resulting S-N curves can then be used to improve the accuracy of fatigue life estimations. X-ray diffraction was used to determine the residual stress in the thread root of the test bolts while light and scanning electron microscopy were used to image the thread root grain structure. Unflawed and flawed aerospace bolts were fatigue tested at a maximum stress (S) ranging from the ultimate tensile strength (UTS) to the surface endurance limit of the test bolt and at several loading ratios between 0.0&lt;R&lt;1.0. The cycles to failure (Nf) and corresponding stress (S) were recorded for 143 specimens.
The thread root, residual compressive stress reached 65 % of the bolt UTS. The residual stresses are the result of the cold-rolled thread forming and grain distortion/alignment. The S-Nf plots showed a 10 % reduction in allowable fatigue stress due to a flaw. The unflawed bolt S-Nf curves showed typical variation with loading ratio (R) and reductions in fatigue strength below that of the fatigue strength of the bolt material (unnotched).
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part I: State-of-Practice Bolt Crack Growth Analyses Methods
Authors: Olsen Kirk W. 
Published: January 2009

Abstract
To perform accurate crack growth analyses on roll-threaded fasteners, aerospace designers are required to estimate fatigue crack growth in the threads of a nut-loaded, roll-threaded bolt under tensile fatigue conditions. Threaded fasteners are difficult to analyze due to their asymmetrical geometry and fastener fatigue crack growth data are scant, especially for nondimensionalized crack depths of (a/d)&lt;0.1. Thus, aerospace designers must make simplifying assumptions and perform analyses with presumably conservative methods. History has shown that improper design assumptions/methods on other critical aircraft components has led to catastrophic failures. Because many fasteners are flight safety critical, their analyses must be accurate. Five leading methods to determine the stress intensity multiplication factor, Y(a/d), for threaded fasteners, based on experimental data, analytic equations, or FE methods, or a combination there of, are compared. By comparing and considering these five methods together, critical observations are made to guide future research based on these state-of-practice Y(a/d) solution methods.
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part IV: Numeric Analyses and Synthesis of All Results
Authors: Olsen Kirk W. , Rimnac Clare M. , Wawrzynek Paul A. , Carter Bruce J. 
Published: January 2009

Abstract
The objective of this research was to determine the stress intensity multiplication factor (Y), as a function of the nondimensionalized crack depth (a/d), in the threads of a nut-loaded, aerospace, roll-threaded bolt under tensile fatigue conditions as a/d approaches zero. The proposed Y(a/d) solution can be used to improve fatigue crack growth life estimations. The research objectives were achieved through bolt material/stress state characterization, cyclic testing, and numeric modeling. The fracture analysis code FRANC3D was used because it could predict crack front shape and stress intensity factor (K). The numeric models predicted a changing crack front and stress intensity factors similar to the test data. The numeric studies accounted for the residual stresses measured by X-ray diffraction within the thread root of the test bolts. The FRANC3D model predicted Y(a/d) at shallow crack depths in the range of 0.01&lt;a/d&lt;0.11. By curve fitting the numeric and experimental data, a new Y(a/d) solution was determined: Y(a/d)=3079(a/d)6−6779(a/d)5+5757(a/d)4−2340(a/d)3+478.6(a/d)2−46.94(a/d)+2.506. The use of this Y(a/d) solution produces conservative crack growth life estimates relative to popular/benchmark methods. Based on test bolt fatigue data, greater accuracy may be possible with this Y(a/d) solution.