bluuebunny/crossref_metadata_2025 huggingface dataset:
La coupe d’orfèvrerie sassanide du Cabinet des médailles : nouvelle attribution
Authors: Villela-Petit Inès
Published: February 2017

La célèbre coupe d’orfèvrerie sassanide du Cabinet des médailles est traditionnellement attribuée au roi «Chosroès » . Le rôle des séries monétaires pour l’identification des effigies royales de la dynastie est reconnu de longue date, mais les progrès considérables faits en un siècle par la numismatique sassanide n’avaient pas encore été pleinement suivis d’effet dans l’interprétation de l’oeuvre, que nous proposerons ici de réattribuer au roi Kavadh Ier. Les comparaisons iconographiques doivent toujours tenir compte du contexte d’usage des objets, monnaies d’un côté, vaisselle de l’autre.
Empirical Evaluations of Interactive Systems in Cultural Heritage
Authors: Koutsabasis Panayiotis
Published: February 2017

An increasing number of interactive systems aim to enhance the user experience (UX) of visitors at museums, archaeological places and cultural sites. This paper presents a review of empirical evaluations of interactive systems in cultural heritage (CH) based on a systematically selected sample of 53 publications from 2012-2016. Empirical evaluations examine the degree an interactive system satisfies user goals and expectations and are inherently complex activities that require careful planning and selection of methods. The review reports on (a) interactive systems of CH in terms of: purpose, technology, cultural content and location of interaction and (b) methods of empirical evaluation in terms of: dimensions of UX, general approach, data collection and participants. The paper provides discussion, critique and outlook on issues including: extending the evaluation dimensions towards the cultural value and the essence of interactivity; placing more consideration on CH professionals; identifying new evaluation methods that balance qualitative results to evidence-based approaches.
Influence of Synthesis Parameters on the Microstructure and Mechanical Property of Thermoplastic Starch
Authors: Vasquez Jasmin Z. , Ongkiko Aileen Grace M. , Diaz Leslie Joy L.
Published: February 2017

Thermoplastic starch was prepared via compression molding in a stainless steel mold having dimensions of 150 mm x 150 mm x 2mm. Thermoplastic starch was prepared by varying the compression temperature, compression pressure and duration of compression. The starch was extracted from bitter cassava (Manihot esculenta crantz), Datu 1 variety. Tensile properties of the material were found to be dependent on the specific conditions at which molding was done. Factorial analysis showed a significant effect of the temperature-pressure interaction on the tensile strength of thermoplastic starch at 95% confidence level. Thermoplastic starch prepared using the compression molding parameters of 105°C and 6.89 MPa (1000 psi) compression pressure exhibited the highest tensile strength of 464.88 kPa. However, using the molding parameters of 105°C and 6.89 MPa (2000 psi) compression pressure exhibited the lowest tensile strength of 416.64 kPa. Introduction of gelatinizing agents and compression molding up to 105 °C and 13.79 MPa (2000 psi) has partially caused the transformation of the microstructure of starch to a more amorphous state. This is shown by the disappearance of peaks at diffraction angles (2θ) of 12.45° (d1 = 0.71 nm), 14.85° (d2 = 0.6 nm), and 17.04° (d3 = 0.52 nm) and the increase in FWHM value at diffraction angle of 22.94° (d4 = 0.39 nm) from 3.05° (starch) to 11.43° (TPS).
Photocatalytic Degradation of Methylene Blue by the La-N/TiO2 Composite and its Kinetic Enumeration
Authors: Gao Jing Li , Han Ying Hui , Li Yu Juan , Zhang Xiao Hong
Published: February 2017

Photocatalytic degradation kinetics of methylene blue in aqueous solution was systematically investigated using Ti-based composite material as the photocatalyst. The single-variable-at-a-time ( SVAT) method was employed. It studied the individual and synergistic effects of several classical parameters on photocatalytic efficiencies. The kinetic mechanism was systematically explored. The kinetics effects of the doping amount of La and N, calcination temperature and time, light intensity were studied in detail. The factors on the degradation of MB were in accordance with the pseudo first order kinetic model. This kinetic model followed the Langmuir–Hinshelwood model. The best preparation conditions were found in the experiments. It is proved that the Ti-based composite material is an effective adsorbent for the degradation of dye contaminated water.
Design of a Novel Locomotion Mechanism of Power Transmission Line Inspection Robot
Authors: Yue Xiang , Wang Hong Guang , Jiang Yong
Published: February 2017

The working environment of the inspection robot is a high altitude flexible cable environment. The robot navigating process must be stable and reliable. The robot mechanism grips the line though locomotion mechanism when navigating obstacles. The locomotion mechanism needs to have a strong clamping capacity and stability. According to the environmental characteristics of transmission lines, a novel locomotion mechanism of inspection robot is presented. The locomotion mechanism adopting differential mechanism can grip different diameter lines. The Tri-Step reducer design to ensure that the various model lines of rapid firmly clamped. The locomotion mechanism is introduced, and the gripper force is analyzed. The experiment results demonstrate that the mechanism has such characteristics as strong grip ability, good motion stability, and different diameter lines gripping capability.
Effect of Wind Turbine Blade Profile Symmetry on Ice Accretion
Authors: Virk Muhammad S.
Published: February 2017

A multiphase numerical study has been carried out to understand the effects of wind turbine blade profile (airfoil) symmetry on resultant ice accretion. Two symmetric (NACA 0006 & 0012) and two non-symmetric airfoils (NACA 23012 & N-22) were used for this preliminary study. Based upon the airflow field calculations and super cooled water droplets collision efficiency, the rate and shape of accreted ice was simulated for rime ice conditions. Analysis showed higher air velocity along top surface of the non-symmetric airfoils as compared to symmetrical airfoils that also effects the droplet behavior and resultant ice growth. Results show that change in blade profile symmetry effects the resultant ice accretion. For symmetric airfoils, more streamlines ice shapes were observed along leading edge as compared to non- symmetric airfoils.
Research and Design of Intelligent Bidet Seat System for Aged People
Authors: Yu Zhi Peng , Cai Ze Fan , Wu Zhuo
Published: February 2017

The purpose of this design is to realize the function of the suitable aging intelligent sit in the vertical lift of the seat plate and a certain angle. The design of the stepper motor, trapezoidal screw rod, motor, mechanical structure of composite roller bearing and other mechanical parts, to achieve steady and rapid upgrade to the designated seat height, and the inclined seat plate in a certain range, convenient for the user to contact with the hip seat board, lack of auxiliary force users (especially the old people sit down to the toilet) to complete the action, reducing the population toileting difficulties.
Failure Analysis of the Laser-Welded Web-Core Steel Sandwich Panel with Narrow Weld Width T-Joints
Authors: Jiang Xiao Xia , Fei Shang Cai , Zhang Shuai , Ji Hua , Zhu Liang
Published: February 2017

Static three-point bending test of the laser welded Web-core steel sandwich panel was performed. The deformation and failure of the sandwich panel with narrow weld width T-Joints were investigated. The results indicate that the deformation undertakes the following three stages: elastic deformation, plasticity deformation and T-joints cracking. The initial yield load is 25 kN, The maximum bending load is 54 kN. The high strength rate characteristic not be fully reflected. The finite simulation result shows the whole structure has no chance to reach the designed maximum value when the T-joints formed plasticity rings. Then the plastic region was developing till the weld cracked. We considered that the T-joint’s cracking is a new failure mode for the web-core steel sandwich panel. Thus, the laser welded T-joints with narrow weld width are the weakest location for the total structure. It is very necessary to consider the T-joint’s geometrical and mechanical properties for the total structural design.
Coal Mine Hydraulic Fracturing Underground Drainage Research and Engineering Application
Authors: Fu Jun Hui , Wen Guang Cai , Lin Fu Jin , Sun Hai Tao , Li Ri Fu , Wu Wen Bin
Published: February 2017

Using elastic mechanics and fracture mechanics, analyzing the coal seam hydraulic fracturing breakdown pressure, given its theoretical formula. According to hydraulic fracturing stress status, given the form of two typical hydraulic fracture morphology. Analyzing hydraulic fracturing highly elliptical shape. The displacement field in plane stress state is given, and the theoretical formula of fracturing radius of hydraulic fracturing is deduced. The fracturing technology of underground fracturing is presented, and the fracturing location and fracturing parameters are determined. In Sihe Coal Mine conducted fracturing test, the test results showed that: the average of drainage volume of fracturing hole improved 4.4 times compared with non-pressed-hole. The extraction compliance time is reduced by 38%. Roadway tunneling speed was improved by 15%. It can solve the problem of gas overrun in roadway excavation well, and has a good application and popularization value.
Synthesis, Characterization and Photocatalytic Activity of La2O3-N/TiO2 for Methylene Blue Removal under UV Irradiation
Authors: Gao Jing Li , Han Ying Hui , Li Yu Juan , Zhang Xiao Hong
Published: February 2017

In this work, the novel Ti-based composite material has been synthesized, characterized and studied for the photocatalytic degradation of methylene blue(MB). The effects of the doping amount of La and N, calcination temperature and time, light intensity were studied in detail. The strong synergism of La, N and TiO2 was discussed during the photocatalytic process. The results suggested that the degradation efficiency was obviously improved by the Ti-based photocatalyst and the La element could enhance the photocatalytic degradation performance significantly, and the best molar ratio of N and TiO2 was 0.000014:1. The study found that the best preparation conditions can also improve the photocatalytic activity, the optimal material was made after calcining for 4h at 800°C. What is more, the higher illumination power was benifit for the degradation of the MB. It is indicated that the mixed crystal Ti-based composite material being an effective adsorbent for the elimination of the contaminated water by dyes. In addition, the work provide new direction for future research.
Effect of EVA Emulsion on the Properties of Corn Stalk Magnesium Oxychloride Cement Composites
Authors: Li Si Qi , Tian Ying Liang , Xu Chang Wei , Wang Jian Heng , Sun Shi Bing , Qi Hong
Published: February 2017

By the method of EVA emulsion coating, cron stalk-magnesium oxychloride cement composites (C-MOC) was modified to study the effect of EVA emulsion content on C-MOC density, the coefficient of thermal conductivity, water resistance and mechanical properties. Furthermore microstructure of C-MOC was analyzed by SEM. The results show that: with the increase of EVA emulsion content, the coefficient of thermal conductivity and softening of C-MOC increase, but water absorption reduces. When the content is 80%, the flexural strength after 28 days could reach 3.65 MPa and the compressive strength is 4.69 MPa, reaching the maximum. At the same time, C-MOC density is 816 kg/m3 and thermal conductivity is 0.111 W/(m·k). Water absorption is 36% and softening coefficient was 0.47. It is believed that EVA emulsion could form a thin film on the outer surface of the corn stalk by microscopic analysis, increasing the roughness of the straw surface and reducing the gap between the stalk. Since the EVA emulsion has good compatibility with the magnesium oxychloride cement, they could constitute a whole jointly with glue liquid, crystal and fiber, playing the role of enhancing the surface. Therefore, water resistance, thermal conductivity and mechanical properties of C-MOC have been improved effectively.
Investigating the pH Dependence of Ultraviolet Radiation Induced Synthesis of TiO2/Poly(Acrylic Acid) Nanocomposites
Authors: Usman Ken Aldren S. , Trinidad Lawrence John Paulo L. , Espenilla Mel Bryan L. , Payawan Jr. Leon M.
Published: February 2017

In this work, Poly(Acrylic Acid) (PAA) was employed as nanoparticle stabilizer for TiO2. Adsorption and encapsulation of nanoparticles in polyelectrolytes impart stability due to stearic and electrostatic effects. Crosslinking of the polymer through UV-Irradiation permanently encapsulates the metal as well as reinforces the polymer cage. The efficient pH and ratio of reactants were optimized then assessed through Dynamic Light Scattering (DLS) for particle size and Zeta Potential Measurements for stability in aqueous solutions. Results showed that among the various TiO2/PAA ratios, the 1:3 ratio showed minimal changes on the size and Zeta Potential values even when exposed to various pH conditions. Meanwhile at pH 5, TiO2 attained a positive surface charge, while PAA exists in its deprotonated form, thus maximizing the electrostatic interaction between the two materials. Analysis revealed that in that particular ratio and pH range, particles size and zeta-potential value of 61.79 nm and -36 mV were obtained respectively. Physical morphology of the nanocomposites was characterized through Scanning Electron Microscopy, showing agglomerates of small particles, resulting to larger particles. Further studies shall be done to utilize the potential of the polymer-coated nanoparticles in dry form.
What are the key characteristics of a Christian life? A comparison of the ethics of Calvin to that of Augustine and their relevance today
Authors: Van Wyk J.H.
Published: February 2017

Augustine and Calvin are two of the greatest (western) theologians of all times and it is illuminating and inspiring to investigate what they have to teach as far as Christian life is concerned. Augustine never wrote a work on Christian ethics in the modern sense of the word but from his many writings we can easily deduce what the key characteristics are. He accepted the natural virtues of philosophers (prudence, for- titude, temperance and justice) but subordinated them to the “infused virtues” of faith, hope and love. Special attention was also paid to inter alia happiness, humility and truth. Calvin, on the other hand, although following Augustine in many aspects of theology, rejected the virtue ethics of the Greek philosophers and developed a Christological ethics within the broader context of pneumatology. The key characteristics of a Christian life are self-denial, cross-bearing and meditation on the future life – and of course the correct enjoyment of the present life. Although we appreciate much of what the two church fathers have to say, we live in a totally different world context today, facing challenges of far greater proportions, like economical uncertainty, political instability and an immense ecological crisis. Morality is chal- lenged today as never before in world history. Today we have to rethink the relevance of Christian life not only from an individual personal perspective but also in terms of broader social Christian ethics.
Calvin, Augustine of Hippo and South Africa: in discussion with Johannes van Oort
Authors: Hofmeyr J.W.
Published: February 2017

In this article the curtain is raised on the interesting and fascinating relation between Augustine of Hippo and John Cal- vin from Geneva, as seen through the eyes of the Dutch scholar Johannes van Oort. The influences of and links between Augustine and Calvin are immense. This has been the focus of various studies in the past. The purpose of this article is, however, not to re-invent the wheel about these relations, but rather to reflect on one of the most eminent scholars on Augustine, i.e. Van Oort’s vision on these links and to enter into a dialogue with him so as to shed some new light on this topic and on some aspects related to ecclesiology. After attention to the use of Augustine by Calvin, the focus is on the discussion with Van Oort and eventually on the relevance of this for us in South(ern) Africa. It is concluded that in this era of post- modernism and relativism as well much can be learnt from both Augustine and Calvin, and especially with regard to the well- being of the church.
Calvin on church and government
Authors: Dreyer W.A.
Published: February 2017

This article examines Calvin’s understanding of civil govern- ment as well as the relationship between church and govern- ment against the background of radical political change during the sixteenth century. It becomes clear that Calvin had an organic understanding of church, government and people. These three entities are interwoven and interact on the basis of the covenant and civil contract. Calvin’s approach, however, is not limited to the covenant, but has a surprising richness and diversity. He integrated theological, juristic and philosophical concepts in his understanding of the state. It is further shown that Calvin’s high regard for civil government, entrenched the corpus christianum, even though he clearly distinguished between ecclesiastical and civil governance. It is also shown that Calvin had a fundamental influence on many of the political concepts which are generally accepted within modern democra- cies.
Bybelse perspektiewe oor hoop
Authors: De Klerk Ben J.
Published: February 2017

No abstract available.
B-cell epitopes of African horse sickness virus serotype 4 recognised by immune horse sera
Authors: Mathebula Evans M. , Faber Frederika E. , Van Wyngaardt Wouter , Van Schalkwyk Antoinette , Pretorius Alri , Fehrsen Jeanni
Published: February 2017

Identifying antigenic proteins and mapping their epitopes is important for the development of diagnostic reagents and recombinant vaccines. B-cell epitopes of African horse sickness virus (AHSV) have previously been mapped on VP2, VP5, VP7 and NS1, using mouse, rabbit and chicken monoclonal antibodies. A comprehensive study of the humoral immune response of five vaccinated horses to AHSV-4 antigenic peptides was undertaken. A fragmented-genome phage display library expressing a repertoire of AHSV-4 peptides spanning the entire genome was constructed. The library was affinity selected for binders on immobilised polyclonal immunoglobulin G (IgG) isolated from horse sera collected pre- and post-immunisation with an attenuated AHSV-4 monovalent vaccine. The DNA inserts of binding phages were sequenced with Illumina high-throughput sequencing. The data were normalised using preimmune IgG-selected sequences. More sequences mapped to the genes coding for NS3, VP6 and VP5 than to the other genes. However, VP2 and VP5 each had more antigenic regions than each of the other proteins. This study identified a number of epitopes to which the horse’s humoral immune system responds during immunisation with AHSV-4.
Intelligent Heuristic Techniques for the Optimization of the Transshipment and Storage Operations at Maritime Container Terminals
Authors: Expósito-Izquierdo Christopher
Published: February 2017

This paper summarizes the main contributions of the Ph.D. thesis of Christopher Exp\'osito-Izquierdo. This thesis seeks to develop a wide set of intelligent heuristic and meta-heuristic algorithms aimed at solving some of the most highlighted optimization problems associated with the transshipment and storage of containers at conventional maritime container terminals. Under the premise that no optimization technique can have a better performance than any other technique under all possible assumptions, the main point of interest in the domain of maritime logistics is to propose optimization techniques superior in terms of effectiveness and computational efficiency to previous proposals found in the scientific literature when solving individual optimization problems under realistic scenarios. Simultaneously, these optimization techniques should be enough competitive to be potentially implemented in practice. }}
Effect of Direct Vertebral Rotation on the Uninstrumented Lumbar Curve in Thoracic Adolescent Idiopathic Scoliosis
Authors: Kim Sung-Soo , Kim Jung-Hoon , Suk Se-Il
Published: February 2017

Study Design

Retrospective study.

Purpose

To determine the effect and direction of direct vertebral rotation (DVR) in the lowest instrumented vertebra (LIV) on the uninstrumented lumbar curve depending on the lumbar modifier used for the correction of thoracic adolescent idiopathic scoliosis.

Overview of Literature

DVR in the LIV should be implemented in a different direction to obtain better spontaneous lumbar correction depending on the preoperative lumbar spine modifier.

Methods

We retrospectively analyzed 160 patients with thoracic adolescent idiopathic scoliosis treated by pedicle screw instrumentation and rod derotation. Patients who had a distal fusion level between T11 and L1 were divided into two groups: the DVR group versus the No-DVR group. Each group was divided into subgroups depending on the lumbar modifier used: the DVR-A, B, and C groups versus the No-DVR-A, B, and C groups. The DVR-A group was subdivided into two subgroups depending on the direction of screw rotation in the LIV: the DVR-A-O group (opposite direction) and the DVR-A-S group (same direction).

Results

There were no significant differences in the preoperative curve characteristics between the two groups. The preoperative lumbar curve was corrected in 70% of the patients in the DVR group and in 56% in the No-DVR group. Spontaneous coronal correction of the lumbar curve was better in the DVR-A-S group than that in the No-DVR-A group. However, the DVR-A-O group had the higher incidence of adding-on deformity. The DVR-B and C groups showed better spontaneous correction of lumbar coronal magnitude, apical vertebral translation, and rotation and the LIV tilting.

Conclusions

In lumbar modifiers B and C, screws in the LIV have to be rotated opposite to the direction of the screw rotation of the main thoracic curve; however, in modifier A, the screws have to be rotated in the same direction.
Short Segment versus Long Segment Pedicle Screws Fixation in Management of Thoracolumbar Burst Fractures: Meta-Analysis
Authors: Aly Tarek Ahmed
Published: February 2017

Posterior pedicle screw fixation has become a popular method for treating thoracolumbar burst fractures. However, it remains unclear whether additional fixation of more segments could improve clinical and radiological outcomes. This meta-analysis was performed to evaluate the effectiveness of fixation levels with pedicle screw fixation for thoracolumbar burst fractures. MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Springer, and Google Scholar were searched for relevant randomized and quasirandomized controlled trials that compared the clinical and radiological efficacy of short versus long segment for thoracolumbar burst fractures managed by posterior pedicle screw fixation. Risk of bias in included studies was assessed using the Cochrane Risk of Bias tool. Based on predefined inclusion criteria, Nine eligible trials with a total of 365 patients were included in this meta-analysis. Results were expressed as risk difference for dichotomous outcomes and standard mean difference for continuous outcomes with 95% confidence interval. Baseline characteristics were similar between the short and long segment fixation groups. No significant difference was identified between the two groups regarding radiological outcome, functional outcome, neurologic improvement, and implant failure rate. The results of this meta-analysis suggested that extension of fixation was not necessary when thoracolumbar burst fracture was treated by posterior pedicle screw fixation. More randomized controlled trials with high quality are still needed in the future.
A Novel Patient-Specific Drill Guide Template for Pedicle Screw Insertion into the Subaxial Cervical Spine Utilizing Stereolithographic Modelling: An In Vitro Study
Authors: Bundoc Rafael Cruz , Delgado Giorgio De Guzman , Grozman Samuel Arsenio Munoz
Published: February 2017

Study Design

Cadaveric study.

Purpose

The purpose of this study was to assess the accuracy and feasibility of cervical pedicle screw (CPS) insertion into the subaxial cervical spine placed using a patient-specific drill guide template constructed from a stereolithographic model.

Overview of Literature

CPS fixation is an invaluable tool for posterior cervical fixation because of its biomechanical advantages. The major drawback is its narrow corridor that allows very little clearance for neural and vascular injuries.

Methods

Fifty subaxial pedicles of the cervical vertebrae from five cadavers were scanned into thin slices using computed tomography (CT). Digital imaging and communications in medicine images of the cadaver spine were digitally processed and printed to scale as a three-dimensional (3D) model. Drill guide templates were manually moulded over the 3D-printed models incorporating pins inserted in the pedicles. The drill guide templates were used for precise placement of the drill holes in the pedicles of cadaveric specimens for pedicle screw fixation.

Results

The instrumented cadaveric spines were subjected to CT to assess the accuracy of our pedicle placement by an external observer. Our patient-specific drill guide template had an accuracy of 94%.

Conclusions

The use of a patient-specific drill guide constructed using stereolithography improved the accuracy of CPS placement in a cadaveric model.
Assessment of Regional Bone Density in Fractured Vertebrae Using Quantitative Computed Tomography
Authors: Soliman Hany A.G. , Mac-Thiong Jean-Marc , Levasseur Annie , Parent Stefan , Petit Yvan
Published: February 2017

Study Design

Cohort study.

Purpose

The aim of this study is to propose and evaluate a new technique to assess bone mineral density of fractured vertebrae using quantitative computed tomography (QCT).

Overview of Literature

There is no available technique to estimate bone mineral density (BMD) at the fractured vertebra because of the alterations in bony structures at the fracture site.

Methods

Forty patients with isolated fracture from T10 to L2 were analyzed from the vertebrae above and below the fracture level. Apparent density (AD) was measured based on the relationship between QCT images attenuation coefficients and the density of calibration objects. AD of 8 independent regions of interest (ROI) within the vertebral body and 2 ROI within the pedicles of vertebrae above and below the fractured vertebra were measured. At the level of the fractured vertebra, AD was measured at the pedicles, which are typically intact. AD of the fractured vertebral body was linearly interpolated, based on the assumption that AD at the fractured vertebra is equivalent to the average AD measured in vertebrae adjacent to the fracture. Estimated and measured AD of the pedicles at the fractured level were compared to verify our assumption of linear interpolation from adjacent vertebrae.

Results

The difference between the measured and the interpolated density of the pedicles at the fractured vertebra was 0.006 and 0.003 g/cm3 for right and left pedicle respectively. The highest mean AD located at the pedicles and the lowest mean AD was found at the anterior ROI of the vertebral body. Significant negative correlation exist between age and AD of ROI in the vertebral body.

Conclusions

This study suggests that the proposed technique is adequate to estimate the AD of a fractured vertebra from the density of adjacent vertebrae.
Novel Landmark for Cervical Pedicle Screw Insertion Point from Computed Tomography-Based Study
Authors: Nishizawa Kazuya , Mori Kanji , Nakamura Akira , Imai Shinji
Published: February 2017

Study Design

Cross-sectional study.

Purpose

The purpose of this study was to evaluate a novel landmark for the cervical pedicle screw insertion point.

Overview of Literature

To improve the accuracy of pedicle screw placement, several studies have employed the lateral mass, lateral vertical notch, and/or inferior articular process as landmarks; however, we often encounter patients in whom we cannot identify accurate insertion points for pedicle screws using these landmarks because of degenerative changes in the facet joints. The superomedial edge of the lamina is less affected by degenerative changes, and we hypothesized that it could be a new landmark for identifying an accurate cervical pedicle screw insertion point.

Methods

A total of 327 consecutive patients, who had undergone neck computed tomographic scanning for determination of neck disease in our institute, were included in the study. At first, the line was drawn parallel to the superior border of the pedicle in the sagittal plane and parallel to the vertical body in the coronal plane. The line was moved downward in 1-mm increments to the inferior border of the pedicle. We determined whether the line passing through the superomedial edge of the lamina (termed the “N-line”) was located between the superior and inferior borders of the pedicle in the sagittal plane.

Results

The percentages of N-lines located between the superior and inferior borders of the pedicle were 100% at C3, 100% at C4, 99% at C5, 96% at C6, and 97% at C7. The lower cervical spine has the higher N-line location.

Conclusions

The N-line was frequently located at the level of the pedicle of each cervical spine in the sagittal plane. The superomedial edge of the lamina could be a new landmark for the insertion point of the cervical pedicle screw.
Improving volcanic ash predictions with the HYSPLIT dispersion model by assimilating MODIS satellite retrievals
Authors: Chai Tianfeng , Crawford Alice , Stunder Barbara , Pavolonis Michael J. , Draxler Roland , Stein Ariel
Published: February 2017

Abstract. Currently, the National Oceanic and Atmospheric Administration (NOAA) National Weather Service (NWS) runs the HYSPLIT dispersion model with a unit mass release rate to predict the transport and dispersion of volcanic ash. The model predictions provide information for the Volcanic Ash Advisory Centers (VAAC) to issue advisories to meteorological watch offices, area control centers, flight information centers, and others. This research aims to provide quantitative forecasts of ash distributions generated by objectively and optimally estimating the volcanic ash source strengths, vertical distribution, and temporal variations using an observation-modeling inversion technique. In this top-down approach, a cost functional is defined to quantify the differences between the model predictions and the satellite measurements of column-integrated ash concentrations weighted by the model and observation uncertainties. Minimizing this cost functional by adjusting the sources provides the volcanic ash emission estimates. As an example, MODIS (Moderate Resolution Imaging Spectroradiometer) satellite retrievals of the 2008 Kasatochi volcanic ash clouds are used to test the HYSPLIT volcanic ash inverse system. Because the satellite retrievals include the ash cloud top height but not the bottom height, there are different model diagnostic choices for comparing the model results with the observed mass loadings. Three options are presented and tested. Although the emission estimates vary significantly with different options, the subsequent model predictions with the different release estimates all show decent skill when evaluated against the unassimilated satellite observations at later times. Among the three options, integrating over three model layers yields slightly better results than integrating from the surface up to the observed volcanic ash cloud top or using a single model layer. Inverse tests also show that including the ash-free region to constrain the model is not beneficial for the current case. In addition, extra constraints on the source terms can be given by explicitly enforcing no-ash for the atmosphere columns above or below the observed ash cloud top height. However, in this case such extra constraints are not helpful for the inverse modeling. It is also found that simultaneously assimilating observations at different times produces better hindcasts than only assimilating the most recent observations.
A record of Neogene seawater δ11B reconstructed from paired δ11B analyses on benthic and planktic foraminifera
Authors: Greenop Rosanna , Hain Mathis P. , Sosdian Sindia M. , Oliver Kevin I. C. , Goodwin Philip , Chalk Thomas B. , Lear Caroline H. , Wilson Paul A. , Foster Gavin L.
Published: February 2017

Abstract. The boron isotope composition (δ11B) of foraminiferal calcite reflects the pH and the boron isotope composition of the seawater the foraminifer grew in. For pH reconstructions, the δ11B of seawater must therefore be known, but information on this parameter is limited. Here we reconstruct Neogene seawater δ11B based on the δ11B difference between paired measurements of planktic and benthic foraminifera and an estimate of the coeval water column pH gradient from their δ13C values. Carbon cycle model simulations underscore that the ΔpH–Δδ13C relationship is relatively insensitive to ocean and carbon cycle changes, validating our approach. Our reconstructions suggest that δ11Bsw was  ∼  37.5 ‰ during the early and middle Miocene (roughly 23–12 Ma) and rapidly increased during the late Miocene (between 12 and 5 Ma) towards the modern value of 39.61 ‰. Strikingly, this pattern is similar to the evolution of the seawater isotope composition of Mg, Li and Ca, suggesting a common forcing mechanism. Based on the observed direction of change, we hypothesize that an increase in secondary mineral formation during continental weathering affected the isotope composition of riverine input to the ocean since 14 Ma.
Regional and global climate for the mid-Pliocene using CCSM4
and PlioMIP2 boundary conditions
Authors: Chandan Deepak , Peltier W. Richard
Published: February 2017

Abstract. The Pliocene Model Intercomparison Project, Phase 2 (PlioMIP2) is an international collaboration to simulate the climate of the mid-Pliocene interglacial, marine isotope stage KM5c (3.205 Mya), using a wide selection of climate models with the objective of understanding the nature of the warming that is known to have occurred during the broader mid-Pliocene warm period. PlioMIP2 builds upon the successes of PlioMIP by shifting focus onto a specific interglacial and by using a revised set of geographic and orbital boundary conditions. In this paper, we present the details of the mid-Pliocene simulations that we have performed with the Community Climate System Model version 4 (CCSM4), and the enhanced variant of the PlioMIP2 boundary conditions, and discuss the simulated climatology through comparisons to our control simulations, and to proxy reconstructions of the climate of the mid-Pliocene. With the new boundary conditions, the CCSM4 model simulates a mid-Pliocene which is more than twice as warm as that with the boundary conditions used for PlioMIP Phase 1. The warming is more enhanced near the high-latitudes which is where most of the changes to the boundary conditions have been made. The elevated warming in the high-latitudes leads to a better match of the simulated climatology to proxy based reconstructions than what was possible with the previous version of the boundary conditions.
Coupling slope–area analysis, integral approach and statistic tests to steady-state bedrock river profile analysis
Authors: Wang Yizhou , Zhang Huiping , Zheng Dewen , Yu Jingxing , Pang Jianzhang , Ma Yan
Published: February 2017

Abstract. Slope–area analysis and the integral approach have both been widely used in stream profile analysis. The former is better at identifying changes in concavity indices but produces stream power parameters with high uncertainties relative to the integral approach. The latter is much better for calculating channel steepness. Limited work has been done to couple the advantages of the two methods and to remedy such drawbacks. Here we show the merit of the log-transformed slope–area plot to determine changes in concavities and then to identify colluvial, bedrock and alluvial channels along river profiles. Via the integral approach, we obtain bedrock channel concavity and steepness with high precision. In addition, we run bivariant linear regression statistic tests for the two methods to examine and eliminate serially correlated residuals because they may bias both the estimated value and the precision of stream power parameters. We finally suggest that the coupled process, integrating the advantages of both slope–area analysis and the integral approach, can be a more robust and capable method for bedrock river profile analysis.
AUTOMATIC RECTIFICATION OF BUILDING FAÇADES
Authors: Tsironis V. , Tranou A. , Vythoulkas A. , Psalta A. , Petsa E. , Karras G.
Published: February 2017

Abstract. Focusing mainly on the case of (near-)planar building façades, a methodology for their automatic projective rectification is described and evaluated. It relies on a suitably configured, calibrated stereo pair of an object expected to contain a minimum of vertical and/or horizontal lines for the purposes of levelling. The SURF operator has been used for extracting and matching interest points. The coplanar points have been separated with two alternative methods. First, the fundamental matrix of the stereo pair, computed using robust estimation, allows estimating the relative orientation of the calibrated pair; initial parameter values, if needed, may be estimated via the essential matrix. Intersection of valid points creates a 3D point set in model space, to which a plane is robustly fitted. Second, all initial point matches are directly used for robustly estimating the inter-image homography of the pair, thus directly selecting all image matches referring to coplanar points; initial values for the relative orientation parameters, if needed, may be estimated from a decomposition of the inter-image homography. Finally, all intersected coplanar model points yield the object-to-image homography to allow image rectification. The in-plane rotation required to finalize the transformation is found by assuming that rectified images contain sufficient straight linear segments to form a dominant pair of orthogonal directions which correspond to horizontality/verticality in 3D space. In our implementation, image edges from Canny detector are used in linear Hough Transform (HT) resulting in a 2D array (ρ, θ) with values equal to the sum of pixels belonging to the particular line. Quantization parameter values aim at absorbing possible slight deviations from collinearity due to thinning or uncorrected lens distortions. By first imposing a threshold expressing the minimum acceptable number of edge-characterized pixels, the resulting HT is accumulated along the ρ-dimension to give a single vector, whose values represent the number of lines of the particular direction. Since here the dominant pair of orthogonal directions has to be found, all vector values are added with their π/2-shifted counterpart. This function is then convolved with a 1D Gaussian function; the optimal angle of in-plane rotation is at the maximum value of the result. The described approach has been successfully evaluated with several building façades of varying morphology by assessing remaining line convergence (projectivity), skewness and deviations from horizontality/verticality. Mean estimated deviation from a metric result was 0°.2. Open questions are also discussed.
Dense water formation in the coastal northeastern Adriatic Sea: the
NAdEx 2015 experiment
Authors: Vilibić Ivica , Mihanović Hrvoje , Janeković Ivica , Denamiel Clea , Poulain Pierre-Marie , Orlić Mirko , Dunić Natalija , Dadić Vlado , Pasarić Mira , Muslim Stipe , Gerin Riccardo , Matić Frano , Šepić Jadranka , Mauri Elena , Kokkini Zoi , Tudor Martina , Kovač Žarko , Džoić Tomislav
Published: February 2017

Abstract. The paper investigates wintertime dynamics of the coastal northeastern Adriatic Sea, and is based on numerical modelling and in situ data collected through field campaigns executed during the winter and spring of 2015. The data have been collected by a variety of instruments and platforms (ADCPs, CTDs, glider, profiling float), and have been accompanied with a one-way coupled ALADIN/ROMS modelling effort. Research focus has been put on dense water formation (DWF), thermal changes and circulation, and water exchange between the coastal and open Adriatic. According to both observations and modelling results, dense waters are formed in the northeastern coastal Adriatic during cold bora outbreaks, even during milder-than-average winters (as was the winter of 2015). However, dense water formed in this coastal region has, due to lower salinities, lower densities than dense water formed at the open Adriatic. Since the sea is deeper in the coastal area than at the open Adriatic, dense waters from the open Adriatic occasionally enter the coastal area near the bottom of the connecting passages, while the surface flow is mostly outward from the coastal area. Median residence time of the coastal area is estimated to about 1–2 months, indicating that the coastal area may be relatively quickly renewed by the open Adriatic waters. The model significantly underestimates currents and transports in connecting channels, which may be a result of a too coarse resolution of atmospheric forcing, misrepresentation of bathymetry or absence of the air-sea feedback in the model. Obtained data represents a comprehensive marine dataset, pointing to a number of interesting phenomena to be investigated in the future.
Recent geodetic mass balance of Monte Tronador glaciers, northern Patagonian Andes
Authors: Ruiz Lucas , Berthier Etienne , Viale Maximiliano , Pitte Pierre , Masiokas Mariano H.
Published: February 2017

Abstract. Glaciers in the northern Patagonian Andes (35–46° S) have shown a dramatic decline in area in the last decades. However, little is known about glacier mass balance changes in this region. This study presents a geodetic mass balance estimate of Monte Tronador (41.15° S; 71.88° W) glaciers by comparing a Pléiades digital elevation model (DEM) acquired in 2012 with the Shuttle Radar Topography Mission (SRTM) X-band DEM acquired in 2000. We find a slightly negative Monte-Tronador-wide mass budget of −0.17 m w.e. a−1 (ranging from −0.54 to 0.14 m w.e. a−1 for individual glaciers) and a slightly negative trend in glacier extent (−0.16 % a−1) over the 2000–2012 period. With a few exceptions, debris-covered valley glaciers that descend below a bedrock cliff are losing mass at higher rates, while mountain glaciers with termini located above this cliff are closer to mass equilibrium. Climate variations over the last decades show a notable increase in warm season temperatures in the late 1970s but limited warming afterwards. These warmer conditions combined with an overall drying trend may explain the moderate ice mass loss observed at Monte Tronador. The almost balanced mass budget of mountain glaciers suggests that they are probably approaching a dynamic equilibrium with current (post-1977) climate, whereas the valley glaciers tongues will continue to retreat. The slightly negative overall mass budget of Monte Tronador glaciers contrasts with the highly negative mass balance estimates observed in the Patagonian ice fields further south.
Optical Coherence Tomography Angiography Features of Chorioretinal Folds: A Case Series
Authors: Del Turco Claudia , Rabiolo Alessandro , Carnevali Adriano , La Spina Carlo , Bettin Paolo , Querques Giuseppe , Bandello Francesco
Published: February 2017

Purpose

To report 3 cases of ocular chorioretinal folds from different etiologies and their aspect with the new imaging technology of optical coherence tomography (OCT) angiography (OCT-A).

Methods

Baseline data, investigational process on etiology, and follow-up data of patients referred for chorioretinal folds to the Medical Retina & Imaging Unit of San Raffaele Hospital in the period January-March 2016 were collected. Multimodal imaging evaluation, comprehensive of infrared, fundus autofluorescence, multicolor, spectral-domain OCT, and OCT-A, was performed on all patients.

Results

Four eyes of 3 men, 65, 46, and 50 years of age, showed chorioretinal folds secondary to central serous chorioretinopathy, postoperative hypotony (after deep sclerectomy), and anisometropia with unilateral hyperopia, respectively. In all cases, OCT-A imaging showed a signal reduction in the choriocapillaris layer in correspondence of the folds. Due to this signal reduction, the en face reconstruction of choriocapillaris layer showed, in all cases, a peculiar tigroid aspect. The aspect of the folds at OCT-A remained unchanged during the 3-month follow-up in all patients.

Conclusions

Optical coherence tomography angiography shows a typical linear signal reduction in the choriocapillaris layer in correspondence of the fold with a tigroid pattern. We hypothesize this aspect could be explained by blood flow alteration at the choriocapillaris level in correspondence of the fold.
Sudden Visual Loss after Cardiac Resynchronization Therapy Device Implantation
Authors: De Vitis Luigi A. , Marchese Alessandro , Giuffrè Chiara , Carnevali Adriano , Querques Lea , Tomasso Livia , Baldin Giovanni , Maestranzi Gisella , Lattanzio Rosangela , Querques Giuseppe , Bandello Francesco
Published: February 2017

Purpose

To report a case of sudden decrease in visual acuity possibly due to a cardiogenic embolism in a patient who underwent cardiac resynchronization therapy (CRT) device implantation.

Methods

A 62-year-old man with severe left ventricular systolic dysfunction and a left bundle branch block was referred to our department because of a sudden decrease in visual acuity. Nine days earlier, he had undergone cardiac transapical implantation of a CRT device, which was followed, 2 days later, by an inflammatory reaction. The patient underwent several general and ophthalmologic examinations, including multimodal imaging.

Results

At presentation, right eye (RE) best-corrected visual acuity (BCVA) was counting fingers and RE pupil was hyporeactive. Fundus examination revealed white-centered hemorrhagic dots suggestive of Roth spots. Fluorescein angiography showed delay in vascular perfusion during early stage, late hyperfluorescence of the macula and optic disk, and peripheral perivascular leakage. The first visual field test showed complete loss of vision RE and a normal left eye. Due to suspected giant cell arteritis, temporal artery biopsy was performed. Thirty minutes after the procedure, an ischemic stroke with right hemisyndrome and aphasia occurred. The RE BCVA worsened to hands motion. Four months later, RE BCVA did not improve, despite improvement in fluorescein angiography inflammatory sign.

Conclusions

We report a possible cardiogenic embolism secondary to undiagnosed infective endocarditis causing monocular visual loss after CRT device implantation. It remains unclear how the embolus caused severe functional damage without altering the retinal anatomical structure.