bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Acetabular Fossa May Not Be Located at the True Center of the Acetabulum
Authors: Shimodaira Hiroki , Tensho Keiji , Akaoka Yusuke , Koyama Suguru , Maruyama Masaaki , Kato Hiroyuki , Saito Naoto 
Published: March 2018

Background:
The acetabular fossa is thought to be located in the center of the acetabulum, and acetabular reaming in total hip arthroplasty is conventionally performed in the center of the fossa. However, the actual location of the fossa and the influence that hypoplasia or deformity may have on the position of the fossa are unknown. We hypothesized that the fossa is located in the center of the acetabulum, regardless of hypoplasia or deformity.

Methods:
Fifty patients with normal hips (normal hip group), 50 patients with dysplasia who underwent rotational acetabular osteotomy (dysplastic hip group), and 46 patients with osteoarthritis who underwent total hip arthroplasty (osteoarthritic hip group) were evaluated by computed tomography (CT) imaging. On the horizontal plane that passes through the center of the femoral head, the center line of the acetabulum was defined as the perpendicular bisector of the anterior and posterior rims of the acetabulum. The angle and distance of the center of the acetabular fossa in relation to the center line of the acetabulum were evaluated; furthermore, the center position of the fossa from the anterior margin of the acetabulum was calculated as a ratio relative to acetabular size. A 1-way analysis of variance was performed to compare measurements among the 3 groups.

Results:
The center of the acetabular fossa was positioned anteriorly to the center line of the acetabulum in all 3 groups. The mean center angle of the acetabular fossa was 14.0° ± 3.8°, 15.2° ± 5.6°, and 14.9° ± 5.5° in the normal, dysplastic, and osteoarthritic hip groups, respectively (p = 0.33). The mean center distance of the acetabular fossa was 5.6 ± 1.8, 5.8 ± 2.3, and 6.1 ± 2.2 mm, respectively (p = 0.55). The mean center position of the acetabular fossa was 38.8% ± 3.3%, 38.5% ± 4.2%, and 38.3% ± 3.9%, respectively (p = 0.71).

Conclusions:
The center of the acetabular fossa is positioned anteriorly to the center of the acetabulum, and the positioning is affected by neither dysplasia nor osteoarthritis. The preconception that the center of the acetabulum corresponds to the center of the acetabular fossa may risk eccentric reaming, possibly damaging the anterior wall.

Level of Evidence:
Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Clinical and Radiographic Outcomes After Posterior Vertebral Column Resection for Severe Spinal Deformity with Five-Year Follow-up
Authors: Riley Max S. , Lenke Lawrence G. , Chapman Todd M. , Sides Brenda A. , Blanke Kathy M. , Kelly Michael P. 
Published: March 2018

Background:
Short-term studies have shown improved outcomes and alignment after posterior vertebral column resection for severe spinal deformity. Our goal was to report long-term changes in radiographic and health-related quality-of-life measures in a consecutive series of pediatric and adult patients undergoing posterior vertebral column resection with a minimum follow-up of 5 years.

Methods:
We reviewed all patients undergoing posterior vertebral column resection by a single surgeon prior to January 1, 2010, at a single institution. Standard preoperative and perioperative data were collected, including the Scoliosis Research Society (SRS)-22/24 instrument. Radiographic and health-related quality-of-life measures changes were evaluated at a minimum follow-up of 5 years.

Results:
One hundred and nine patients underwent posterior vertebral column resection prior to January 2010, and 54 patients (49.5%) were available for analysis: 31 (57.4%) were pediatric patients, and 23 (42.6%) were adult patients. The mean age (and standard deviation) was 12.5 ± 3 years for the pediatric cohort and 39.3 ± 20 years for the adult cohort. Improvements in the mean major Cobb angle at a minimum follow-up of 5 years were seen: 61.6% correction for the pediatric cohort and 53.9% correction for the adult cohort. The rates of proximal junctional kyphosis, defined as proximal junctional kyphosis of >10°, were 16.1% for the pediatric cohort and 34.8% for the adult cohort, but none underwent a revision surgical procedure for symptomatic proximal junctional kyphosis. Of the 54 patients, 30 (55.6%) sustained complications, 5 (9.3%) experienced postoperative neurological deficits, and 7 (13.0%) required a revision by 5 years postoperatively. Significant improvements were observed in the SRS-Self Image with regard to the pediatric cohort at 0.9 (p = 0.017) and the adult cohort at 1.3 (p = 0.002) and in the SRS-Satisfaction with regard to the pediatric cohort at 1.8 (p = 0.008) and the adult cohort at 1.3 (p = 0.005).

Conclusions:
Posterior vertebral column resection offers substantial, sustained improvements in global radiographic alignment and patient outcome scores at 5 years. The major radiographic deformity was reduced by 61.6% in the pediatric cohort and by 53.9% in the adult cohort. Despite the high rate of complications, patients experienced significant improvement in the SRS-Self Image and SRS-Satisfaction domains.

Level of Evidence:
Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
An Inversion Method of Relative Permeability Curves in Polymer Flooding Considering Physical Properties of Polymer
Authors: Liu Yongge , Hou Jian , Liu Lingling , Zhou Kang , Zhang Yanhui , Dai Tao , Guo Lanlei , Cao Weidong 
Published: March 2018

Summary
Reliable relative permeability curves of polymer flooding are of great importance to the history matching, production prediction, and design of the injection and production plan. Currently, the relative permeability curves of polymer flooding are obtained mainly by the steady-state, nonsteady-state, and pore-network methods. However, the steady-state method is extremely time-consuming and sometimes produces huge errors, while the nonsteady-state method suffers from its excessive assumptions and is incapable of capturing the effects of diffusion and adsorption. As for the pore-network method, its scale is very small, which leads to great size differences with the real core sample or the field. In this paper, an inversion method of relative permeability curves in polymer flooding is proposed by combining the polymer-flooding numerical-simulation model and the Levenberg-Marquardt (LM) algorithm. Because the polymer-flooding numerical-simulation model by far offers the most-complete characterization of the flowing mechanisms of polymer, the proposed method is able to capture the effects of polymer viscosity, residual resistance, diffusion, and adsorption on the relative permeability. The inversion method was then validated and applied to calculate the relative permeability curve from the experimental data of polymer flooding. Finally, the effects of the influencing factors on the inversion error were analyzed, through which the inversion-error-prediction model of the relative permeability curve was built by means of multivariable nonlinear regression. The results show that the water relative permeability in polymer flooding is still far less than that in waterflooding, although the residual resistance of the polymer has been considered in the numerical-simulation model. Moreover, the accuracy of the polymer parameters has great effect on that of the inversed relative permeability curve, and errors do occur in the inversed water relative permeability curve—the measurements of the polymer solution viscosity, residual resistance factor, inaccessible pore-volume (PV) fraction, or maximum adsorption concentration have errors.
Interaction Between Proppant Compaction and Single-/Multiphase Flows in a Hydraulic Fracture
Authors: Fan Ming , McClure James , Han Yanhui , Li Zhe , Chen Cheng 
Published: March 2018

SummaryUnderstanding proppant-transport and -deposition patterns in a hydraulic fracture is vital for effective and economical production of petroleum hydrocarbons. In this research, a numerical-modeling approach, combining the discrete-element method (DEM) with single-/multiphase lattice Boltzmann (LB) simulation, was adopted to advance understanding of the interaction between reservoir depletion, proppant-particle compaction, and single-/multiphase flows in a hydraulic fracture. DEM was used to simulate effective-stress increase and the resultant proppant-particle movement and rearrangement during the process of reservoir depletion caused by hydrocarbon production. Simulated pore structure of the proppant pack was extracted and used as boundary conditions in the LB simulation to calculate the time-dependent permeability of the proppant pack. We first validated the DEM-LB numerical work flow, and the simulated proppant-pack permeabilities as functions of effective stress were in good agreement with laboratory measurements. Furthermore, three proppant packs with the same average particle diameter but different diameter distributions were generated to study the role of proppant-size heterogeneity (variation in particle diameter). Specifically, we used the coefficient of variation (COV) of diameter, defined as the ratio of standard deviation of diameter to mean diameter, to characterize the heterogeneity of particle size. We obtained proppant-pack porosity, permeability, and fracture-width reduction (closure distance) as functions of effective stress. Under the same effective stress, a proppant pack with a higher diameter COV had lower porosity and permeability and larger fracture-width reduction. This was because the high diameter COV gave rise to a wider diameter distribution of proppant particles; smaller particles were compressed into the pore space between larger particles with increasing stress, leading to larger closure distance and lower porosity and permeability. With multiphase LB simulation, relative permeability curves were obtained, which are critical for larger-scale reservoir simulations under various effective stresses. The relative permeability of the oil phase was more sensitive to changes in geometry and stress, compared with the wetting phase. This was because the oil phase occupied larger pores; compaction of the proppant pack affected the structure of the pores, because the pores were farther from the grain contacts and thus more susceptible to collapse. It is also interesting to note that when effective stress increased continuously, oil relative permeability increased first and then decreased. This nonmonotonic behavior was the result of the nonmonotonic development of pore structure and oil connectivity under increasing stress.
Fiscalidad e independencia en Panamá, 1780-1845
Authors: Pinto Bernal José Joaquín 
Published: March 2018

El artículo analiza la historia fiscal de Panamá entre 1780 y 1845 a través del estudio de las leyes y series fiscales, interpretadas con base en la situación política y económica de la época. El trabajo está dividido en cuatro secciones: la primera abarca la aplicación de las reformas borbónicas en Panamá; la segunda se ocupa del estudio del fisco durante la crisis del Estado colonial en América; la tercera abarca el período de existencia de la Gran Colombia, y la última concierne a la conformación de la República de la Nueva Granada, hasta 1845. En cada uno de los apartados se hace énfasis en el conflicto presentado entre la élite comercial de Panamá, las autoridades españolas y las bogotanas como producto de la necesidad del comercio libre para la prosperidad económica y estabilidad política en el Istmo.
Avance: Una nota preliminar sobre el desempeño de la economía colombiana desde 1888 hasta 2012. Una nueva serie del PIB
Authors: De Corso Giuseppe 
Published: March 2018

A continuación se presenta un avance de un trabajo en curso, cuyo objetivo es proponer una revisión del comportamiento, en el largo plazo, de por lo menos dos indicadores de la economía colombiana,1 el PIB y el PIB per cápita.
¿ES APLICABLE EL SISTEMA ATLS A LA CIRUGIA TAURINA?
Authors: Tallón Aguilar Luis , López Bernal Francisco de Asis , Sousa Vaquero Jose María , Pareja Ciuró Felipe , Mulet Zayas Octavio , Padillo Ruiz Francisco Javier 
Published: March 2018

Health care in bullfights has its own idiosyncrasy due to causative agent and mechanism of injury. Basic principles ofATLS (Advance Trauma Life Supports) provide a frame of reference for evaluation and treatment. Its application inaltered environments and with limited resources forces us to adapt them to specific circumstances. A critical attitude isimportant by identifying critical points or areas for improvement to ensure their capabilities and limitations. Our objectiveis to perform a review of characteristics of these patients to demonstrate their applicability and validity. The priorityis to save the life of patient, once placed outside the danger area (exposure to bull), being sometimes difficult a correctimmobilizing or cervical control. It has the advantage that medical staff witnesses the trauma which allows him to havea preconceived idea of possible injuries. The professional bullfighter is really an athlete, usually young, healthy and withadequate physical preparation, which means that he does not present early signs of shock and his blood pressure is usuallylow. We believe, based on our experience that the ATLS system is applicable to Taurine Surgery and it is necessary toconsider some of its own characteristics. Los cuidados sanitarios en los festejos taurinos presentan una idiosincrasia propia debido al agente causante y al mecanismode producción de las lesiones. Los principios básicos del ATLS (Advance Trauma Life Supports) proporcionanun marco de referencia para la evaluación y tratamiento de éstas que pueden poner en riesgo la vida del paciente. Suaplicación en ambientes alterados y con recursos limitados nos obliga a adaptarlos a unas circunstancias específicas. Esimportante una actitud crítica identificando los puntos críticos o áreas de mejora para asegurar sus capacidades y sus limitaciones.Nuestro objetivo es realizar una revisión de las características de estos pacientes para demostrar su aplicabilidady validez. La prioridad es salvar la vida del paciente, una vez puesto fuera del área de peligro (exposición al toro) siendodifícil en ocasiones una inmovilización y un control cervical correcto. Dispone de la ventaja de que el personal médicopresencia el trauma lo que le permite tener una idea preconcebida de las posibles lesiones. El torero profesional es realmenteun atleta, habitualmente joven, sano y con una adecuada preparación física, lo que conlleva que no presente signosprecoces de shock y su presión arterial sea usualmente baja. Creemos, basándonos en nuestra experiencia, que el sistemaATLS es aplicable a la Cirugía Taurina siendo necesario considerar algunas características propias.
Self-etching Primers vs Acid Conditioning: Impact on Bond Strength Between Ceramics and Resin Cement
Authors: Tribst JPM , Anami LC , Özcan M , Bottino MA , Melo RM , Saavedra GSFA 
Published: March 2018

SUMMARY
This study tested whether a self-etching surface agent and the conventional hydrofluoric acid (HF) would provide the same bonding capacity between resin cement and feldspathic (Fd) and lithium disilicate (Ld) ceramics. Ceramic blocks were cut with a low-speed diamond saw with water cooling (Isomet 1000, Buehler, Lake Bluff, IL, USA) into 20 blocks of 5 × 7 × 4 mm, which were ground flat in a polishing machine (EcoMet/AutoMet 250, Buehler) under water cooling. The blocks were randomly divided into eight groups (n=5), according to ceramic type (Ld or Fd), surface conditioning (HF + Monobond Plus or Etch and Prime), and aging by thermocycling (TC or absence-baseline). After 24 hours in 37°C distilled water, blocks were embedded into acrylic resin and 1-mm2 cross-section beams composed of ceramic/cement/composite were obtained. The microtensile test was performed in a universal testing machine (DL-1000, EMIC, São José dos Campos, Brazil; 0.5 mm.min−1, 50 kgf load cell). Bond strength (MPa) was calculated by dividing the load at failure (in N) by the bonded area (mm2). The fractured specimens were examined under stereomicroscopy, and one representative sample of each group was randomly selected before the cementation and was further used for analysis using scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS). The self-etching agent showed the highest bond strength for Fd (24.66±4.5) and Ld (24.73±6.9) ceramics and a decrease in surface wettability. SEM and EDS showed the presence of similar components in the tested materials with different topographies for both. Therefore, the self-etching primer was able to deliver even higher bonding than HF+silane to a resin cement.
Effect of Baicalein on Matrix Metalloproteinases and Durability of Resin-Dentin Bonding
Authors: Li J , Chen B , Hong N , Wu S , Li Y 
Published: March 2018

SUMMARYObjective:In an attempt to increase resin-dentin bonding quality, this study used baicalein as a preconditioner in an etch-and-rinse adhesive to evaluate its effect on matrix metalloproteinases (MMPs) and adhesive durability.Methods:As a MMP inhibitor and potential collagen cross-linking agent, baicalein was used as a preconditioner in an etch-and-rinse adhesive system. The degree of conversion was evaluated by Fourier-transform infrared spectroscopy. EnzChek gelatinase/collagenase assay kits were then used to detect the MMP inhibitory effect of different concentrations of baicalein (0.1, 0.5, 2.5, and 5.0 μg/mL) on dentin powders. During in vitro bonding procedures, flat dentin surfaces on sound third molars were preconditioned with 2.5 μg/mL baicalein after being acid-etched; this step was followed by continuation of adhesive processes and build-up of resin composite. After resin-dentin stick preparation, bonding strength, failure mode, and interface nanoleakage were respectively evaluated via microtensile testing, stereomicroscopy, and field emission scanning electron microscopy either immediately or after storage in artificial saliva for three or six months. Data were analyzed by two-way analysis of variance and Tukey test (α=0.05).Results:Baicalein at a concentration of 0-5.0 μg/mL did not influence the conversion of adhesives. However, it inhibited the activities of dentin-bond gelatinase and collagenase, especially at a concentration of 2.5 μg/mL, while effectively increasing microtensile bonding strength and decreasing nanoleakage in vitro, both immediately and after aging.Conclusions:Baicalein used as preconditioner in an etch-and-rinse adhesive system has an anti-MMP function and effectively improves resin-dentin bonding durability in vitro, which has potential value in clinical bonding procedures.
Literasi Matematika Siswa Pendidikan Menengah: Analisis Menggunakan Desain Tes Internasional dengan Konteks Indonesia
Authors: -- Mahdiansyah , -- Rahmawati 
Published: March 2018

The purpose of the study was to measure studentsâ€™ mathematical literacy achievementÂ at secondary education level on the international test design adjusted to the context of Indonesia,Â and to analyze factors affecting the achievement. In addition, to conducting test, the surveyÂ was also administered to obtain data on the test participant students, maths teachers, and theirÂ educational background. Sampling was done by using a multi-stage stratified random sampling.Â This research revealed that the literacy achievement of students was still low, but the disparityÂ of literacy achievement among cities was varied. Student literacy achievement in YogyakartaÂ was relatively evenly compared to other cities. Uncertainty and data is the most easily contentÂ compared to other mathematical contents. Examined from the aspect of context, scientific isÂ the lowest achieved by students.The test items that measure higher order thinking skills (HOTS)Â had not been well mastered by students. There are number of determinants of mathematicsÂ literacy achievement, namely personal factor, instructional factor, and environmental factor.Â The conclusion of the study is studentsâ€™ mathematical literacy at secondary educationlevel wasÂ still low, although the design of international test used had been adjusted by the IndonesianÂ context.ABSTRAKÂ Penelitian ini bertujuan untuk mengukur capaian literasi matematika siswa jenjangÂ pendidikan menengah dengan menggunakan desain tes internasional yang disesuaikan denganÂ konteks Indonesia, serta menganalisis faktor-faktor yang mempengaruhi capaian literasiÂ tersebut. Di samping melakukan tes kepada siswa SMA/MA, survei juga dilakukan untukÂ memperoleh data siswa peserta tes, guru matematika, dan latar belakang pendidikan. PenarikanÂ sampel dilakukan dengan teknik multi-stage stratified random sampling. Hasil penelitianÂ mengungkapka capaian literasi siswa masih rendah, namun disparitas capaian literasi antarkota cukup bervariasi. Capaian literasi siswa Yogyakarta relatif merata dibandingkan dengan kotakotaÂ lainnya. Uncertainty and data merupakan konten yang paling mudah dibandingkan denganÂ konten matematika lainnya. Dikaji dari aspek konteks, scientific merupakan konteks yang palingÂ rendah dicapai siswa. Adapun soal-soal tes yang mengukur kemampuan berpikir tingkat tinggiÂ (higher order thinking skills-HOTS) belum mampu dikuasai siswa dengan baik. Terdapat sejumlahÂ faktor determinan dari capaian literasi matematika tersebut, yaitu faktor personal, faktorÂ instruksional, dan faktor lingkungan. Kesimpulan studi adalah literasi matematika siswa jenjangÂ pendidikan menengah masih rendah, meskipun desain tes internasional yang digunakan telahÂ disesuaikan dengan konteks Indonesia.