bluuebunny/crossref_metadata_2025 huggingface dataset:
Cerebrolysin™ efficacy in a transgenic model of tauopathy: role in regulation of mitochondrial structure
Authors: Rockenstein Edward , Ubhi Kiren , Trejo Margarita , Mante Michael , Patrick Christina , Adame Anthony , Novak Philipp , Jech Marion , Doppler Edith , Moessler Herbert , Masliah Eliezer
Published: July 2014

Background

Alzheimer’s Disease (AD) and Fronto temporal lobar dementia (FTLD) are common causes of dementia in the aging population for which limited therapeutical options are available. These disorders are associated with Tau accumulation. We have previously shown that CerebrolysinTM (CBL), a neuropeptide mixture with neurotrophic effects, ameliorates the behavioral deficits and neuropathological alterations in amyloid precursor protein (APP) transgenic (tg) mouse model of AD by reducing hyper-phosphorylated Tau. CBL has been tested in clinical trials for AD, however it’s potential beneficial effects in FTLD are unknown. For this purpose we sought to investigate the effects of CBL in a tg model of tauopathy. Accordingly, double tg mice expressing mutant Tau under the mThy-1 promoter and GSK3β (to enhance Tau phosphorylation) were treated with CBL and evaluated neuropathologically.

Results

Compared to single Tau tg mice the Tau/GSK3β double tg model displayed elevated levels of Tau phosphorylation and neurodegeneration in the hippocampus. CBL treatment reduced the levels of Tau phosphorylation in the dentate gyrus and the degeneration of pyramidal neurons in the temporal cortex and hippocampus of the Tau/GSK3β double tg mice. Interestingly, the Tau/GSK3β double tg mice also displayed elevated levels of Dynamin-related protein-1 (Drp-1), a protein that hydrolyzes GTP and is required for mitochondrial division. Ultrastructural analysis of the mitochondria in the Tau/GSK3β double tg mice demonstrated increased numbers and fragmentation of mitochondria in comparison to non-tg mice. CBL treatment normalized levels of Drp-1 and restored mitochondrial structure.

Conclusions

These results suggest that the ability of CBL to ameliorate neurodegenerative pathology in the tauopathy model may involve reducing accumulation of hyper-phosphorylated Tau and reducing alterations in mitochondrial biogenesis associated with Tau.
A comparison of hallux valgus angles assessed with computerised plantar pressure measurements, clinical examination and radiography in patients with diabetes
Authors: Janssen Daniël MC , Sanders Antal P , Guldemond Nick A , Hermus Joris , Walenkamp Geert HIM , van Rhijn Lodewijk W
Published: July 2014

Background

Hallux valgus deformity is a common musculoskeletal foot disorder with a prevalence of 3.5% in adolescents to 35.7% in adults aged over 65 years. Radiographic measurements of hallux valgus angles (HVA) are considered to be the most reproducible and accurate assessment of HVA. However, in European countries, many podiatrists do not have direct access to radiographic facilities. Therefore, alternative measurements are desired. Such measurements are computerised plantar pressure measurement and clinical goniometry. The purpose of this study was to establish the agreement of these techniques and radiographic assessments.

Methods

HVA was determined in one hundred and eighty six participants suffering from diabetes. Radiographic measurements of HVA were performed with standardised static weight bearing dorsoplantar foot radiographs.

The clinical goniometry for HVA was measured with a universal goniometer. Computerised plantar pressure measurement for HVA was executed with the EMED SF‐4® pressure platform and Novel‐Ortho‐Geometry software. The intra‐class correlation coefficients (ICC) and levels of agreement were analysed using Bland & Altman plots.

Results

Comparison of radiographic measurements to clinical goniometry for HVA showed an intraclass correlation coefficient (ICC) of 0.81 (95% confidence interval, 0.76 to 0.86; p<0.001). Radiographic measurement versus computerised plantar pressure measurement showed an ICC of 0.59 (95% confidence interval, 0.49 to 0.68; p<0.001). In addition, clinical goniometry versus computerised plantar pressure measurement showed an ICC of 0.77 (95% confidence interval, 0.70 to 0.82; p<0.001). The systematic difference of the computerised plantar pressure measurement compared with radiographic measurement and clinical goniometry was 7.0 degrees (SD 6.8) and 5.2 degrees (SD 5.0), respectively. The systemic difference of radiographic measurements compared with clinical goniometry was 1.8 degrees (SD 5.0).

Conclusions

The agreement of computerised plantar pressure measurement and clinical goniometry for HVA compared to radiographic measurement of HVA is unsatisfactory. Radiographic measurements of HVA and clinical goniometry for HVA yield better agreement compared to radiographic measurements and computerised plantar pressure measurement. The traditional radiographic measurement techniques are strongly recommended for the assessment of HVA.
An EAACI “European Survey on Adverse Systemic Reactions in Allergen Immunotherapy (EASSI)”: the methodology
Authors: Calderón Moises A , Rodríguez del Río Pablo , Vidal Carmen , Just Jocelyne , Pfaar Oliver , Linneberg Allan , Demoly Pascal
Published: July 2014

At present, there is no European report on clinically relevant systemic reactions due to the regular use of allergen immunotherapy (AIT), administered either subcutaneously or sublingually (SCIT and SLIT, respectively) outside clinical trials. Using an electronic survey and a “harmonised terminology” according to MedDRA, we aimed to prospectively collect systemic adverse reactions due to AIT from real life clinical settings.

Under the framework of the EAACI, a team of European specialists in AIT, pharmacovigilance, epidemiology and drugs regulation set up a web‐based prospective pilot survey to be conducted in three European countries (France, Germany and Spain). A designated “national coordinator” was responsible for following ethics requirements relative to each country and to select at least 30 doctors per country.

Patients were recruited the same day they received their first dose of either SCIT or SLIT. Patient inclusion criteria were: adults and children, with IgE mediated pollen, house dust mite, Alternaria, and/or animal dander respiratory allergies who will initiate AIT.

A list of 31 symptoms terms were extracted from the MedDRA (Medical Dictionary for Regulatory Activities) dictionary to harmonize the reporting of all adverse systemic reactions in this survey.

The SurveyMonkey® online instrument was used by participant doctors to submit information directly to a blinded central database.

Three questionnaires were generated: i) the Doctor Questionnaire, ii) the Patient Questionnaire and iii) the Adverse Reaction Questionnaire. A handbook and a mistake report form were given to each doctor.

In this paper, we describe the methodology followed.
The clinical characteristics of dementia with Lewy bodies and a consideration of prodromal diagnosis
Authors: Donaghy Paul C , McKeith Ian G
Published: July 2014

Dementia with Lewy bodies (DLB) is the second most common type of degenerative dementia following Alzheimer’s disease (AD). DLB is clinically and pathologically related to Parkinson's disease (PD) and PD dementia, and the three disorders can be viewed as existing on a spectrum of Lewy body disease. In recent years there has been a concerted effort to establish the phenotypes of AD and PD in the prodromal phase (before the respective syndromes of cognitive and motor impairment are expressed). Evidence for the prodromal presentation of DLB is also emerging. This paper briefly reviews what is known about the clinical presentation of prodromal DLB before discussing the pathology of Lewy body disease and how this relates to potential biomarkers of prodromal DLB. The presenting features of DLB can be broadly placed in three categories: cognitive impairment (particularly nonamnestic cognitive impairments), behavioural/psychiatric phenomena (for example, hallucinations, rapid eye movement sleep behaviour disorder (RBD)) and physical symptoms (for example, parkinsonism, decreased sense of smell, autonomic dysfunction). Some noncognitive symptoms such as constipation, RBD, hyposmia and postural dizziness can predate the onset of memory impairment by several years in DLB. Pathological studies of Lewy body disease have found that the earliest sites of involvement are the olfactory bulb, the dorsal motor nucleus of the vagal nerve, the peripheral autonomic nervous system, including the enteric nervous system, and the brainstem. Some of the most promising early markers for DLB include the presence of RBD, autonomic dysfunction or hyposmia, 123I-metaiodobenzylguanidine cardiac scintigraphy, measures of substantia nigra pathology and skin biopsy for α-synuclein in peripheral autonomic nerves. In the absence of disease-modifying therapies, the diagnosis of prodromal DLB is of limited use in the clinic. That said, knowledge of the prodromal development of DLB could help clinicians identify cases of DLB where the diagnosis is uncertain. Prodromal diagnosis is of great importance in research, where identifying Lewy body disease at an earlier stage may allow researchers to investigate the initial phases of dementia pathophysiology, develop treatments designed to interrupt the development of the dementia syndrome and accurately identify the patients most likely to benefit from these treatments.
Early sedation and clinical outcomes of mechanically ventilated patients: a prospective multicenter cohort study
Authors: Tanaka Lilian Maria Sobreira , Azevedo Luciano Cesar Pontes , Park Marcelo , Schettino Guilherme , Nassar Antonio Paulo , Réa-Neto Alvaro , Tannous Luana , de Souza-Dantas Vicente Ces , Torelly André , Lisboa Thiago , Piras Claudio , Carvalho Frederico Bruzzi , de Oliveira Maia Marcelo , Giannini Fabio Poianas , Machado Flavia Ribeiro , Dal-Pizzol Felipe , de Carvalho Alexandre Guilherme Ribeiro , dos Santos Ronaldo Batista , Tierno Paulo Fernando Guimarães Morando Ma , Soares Marcio , Salluh Jorge Ibrain Figueira ,   for the ERICC study investigators
Published: July 2014

Introduction

Sedation overuse is frequent and possibly associated with poor outcomes in the intensive care unit (ICU) patients. However, the association of early oversedation with clinical outcomes has not been thoroughly evaluated. The aim of this study was to assess the association of early sedation strategies with outcomes of critically ill adult patients under mechanical ventilation (MV).

Methods

A secondary analysis of a multicenter prospective cohort conducted in 45 Brazilian ICUs, including adult patients requiring ventilatory support and sedation in the first 48 hours of ICU admissions, was performed. Sedation depth was evaluated after 48 hours of MV. Multivariate analysis was used to identify variables associated with hospital mortality.

Results

A total of 322 patients were evaluated. Overall, ICU and hospital mortality rates were 30.4% and 38.8%, respectively. Deep sedation was observed in 113 patients (35.1%). Longer duration of ventilatory support was observed (7 (4 to 10) versus 5 (3 to 9) days, P = 0.041) and more tracheostomies were performed in the deep sedation group (38.9% versus 22%, P = 0.001) despite similar PaO2/FiO2 ratios and acute respiratory distress syndrome (ARDS) severity. In a multivariate analysis, age (Odds Ratio (OR) 1.02; 95% confidence interval (CI) 1.00 to 1.03), Charlson Comorbidity Index >2 (OR 2.06; 95% CI, 1.44 to 2.94), Simplified Acute Physiology Score 3 (SAPS 3) score (OR 1.02; CI 95%, 1.00 to 1.04), severe ARDS (OR 1.44; CI 95%, 1.09 to 1.91) and deep sedation (OR 2.36; CI 95%, 1.31 to 4.25) were independently associated with increased hospital mortality.

Conclusions

Early deep sedation is associated with adverse outcomes and constitutes an independent predictor of hospital mortality in mechanically ventilated patients.
Self-referred patients at the Emergency Department: patient characteristics, motivations, and willingness to make a copayment
Authors: de Valk Janneke , Taal Elisabeth M , Nijhoff Mariette S , Harms Maren H , Lieshout Esther MM , Patka Peter , Rood Pleunie PM
Published: July 2014

Background

In many countries, including the Netherlands, a substantial number of patients visit the Emergency Department (ED) without a referral by a general practitioner. The goal of this study was to determine the characteristics and motivations of self-referred patients (SRPs) at the ED. The secondary objective was to explore SRPs’ opinion about copayments.

Methods

A survey, in seven different languages was performed among SRPs from October 2011 until January 2012 at an academic ED in the Netherlands. Patients were included on 21 day-, 21 evening-, and 21 nightshifts during week and weekend days equally. Patient characteristics, motivations, complaints, diagnosis, and the opinion regarding copayments were examined.

Results

A total of 436 SRPs were included (response rate 82%). Forty-seven percent of the ED population was self-referred. SRPs were mainly male (58%), between 18 and 35 years (54%), Dutch (67%), single without children (42%), and low-educated (73%). The most commonly presented complaints were of musculoskeletal origin (35%). Expected need for additional medical care (e.g., X-rays, blood tests) was the reason to visit the ED for 28% of the SRPs. Around 30% of the SRPs were not prepared to pay for an ED visit. Fifty percent of SRPs were prepared to pay up to 25 or 50 EUR. Highly educated patients were willing to pay more than patients with a low level of education (p < 0.05).

Conclusions

SRPs (47% of the total ED population) are often young men with musculoskeletal complaints. They are convinced that additional medical tests are necessary. About 70% of the SRPs are willing to make a copayment, half of the SRPs with a maximum between 25 EUR and 50 EUR. As highly educated SRPs are prepared to pay more, introducing copayments might influence equity in health care accessibility.
Influences of 3-hydroxypropionaldehyde and lactate on the production of 1,3-propanediol by Klebsiella pneumoniae
Authors: Zhong Zhihui , Liu Longfei , Zhou Jiajia , Gao Lirong , Xu Jiajie , Fu Shuilin , Gong Heng
Published: July 2014

Background

1,3-Propanediol is the starting point of a new-generation polymer with superior properties which can be used in many industrial fields. 3-Hydroxypropionaldehyde and lactate have been identified as two important metabolites in the biological route of 1,3-propanediol bioconversion from glycerol. Here, influence of lactate on the inhibition caused by 3-hydroxypropionaldehyde of 1,3-propanediol fermentation by Klebsiella pneumoniae is reported.

Methods

The influences of 3-hydroxypropionaldehyde and lactate on 1,3-propanediol production were investigated in normal and lactate pathway deficient strains with different fermentation conditions.

Results

By using the strains KG1 and L-type lactate dehydrogenase-deficient mutant (KG1Δldh), the results indicated that an early accumulation of 3-hydroxypropionaldehyde directly inhibited the 1,3-propanediol production rather than through lactate accumulation during the late stage of fermentation. Then, the influence of extra addition of lactate on the late stage of fermentation was investigated, and the inhibitory effect of lactate did not appear. At last, it was found that by reducing 3-hydroxypropionaldehyde accumulation in the early stage of fermentation, the concentration and yield of 1,3-propanediol increased by 18% and 16%, respectively, over the initial experimental levels.

Conclusions

An early accumulation of 3-hydroxypropionaldehyde directly decreased the final 1,3-propanediol concentration rather than through lactate accumulation during the late stage of fermentation.
Leaf extract mediated green synthesis of silver nanoparticles from widely available Indian plants: synthesis, characterization, antimicrobial property and toxicity analysis
Authors: Banerjee Priya , Satapathy Mantosh , Mukhopahayay Aniruddha , Das Papita
Published: July 2014

Background

In recent years, green synthesis of silver nanoparticles (AgNPs) has gained much interest from chemists and researchers. In this concern, Indian flora has yet to divulge innumerable sources of cost-effective non-hazardous reducing and stabilizing compounds utilized in preparing AgNPs. This study investigates an efficient and sustainable route of AgNP preparation from 1 mM aqueous AgNO3 using leaf extracts of three plants, Musa balbisiana (banana), Azadirachta indica (neem) and Ocimum tenuiflorum (black tulsi), well adorned for their wide availability and medicinal property.

Methods

AgNPs were prepared by the reaction of 1 mM silver nitrate and 5% leaf extract of each type of plant separately. the AgNPs were duely characterized and tested for their antibacterial activity and toxicity.

Results

The AgNPs were characterized by UV-visible (vis) spectrophotometer, particle size analyzer (DLS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS). Fourier transform infrared spectrometer (FTIR) analysis was carried out to determine the nature of the capping agents in each of these leaf extracts. AgNPs obtained showed significantly higher antimicrobial activities against Escherichia coli (E. coli) and Bacillus sp. in comparison to both AgNO3 and raw plant extracts. Additionally, a toxicity evaluation of these AgNP containing solutions was carried out on seeds of Moong Bean (Vigna radiata) and Chickpea (Cicer arietinum). Results showed that seeds treated with AgNP solutions exhibited better rates of germination and oxidative stress enzyme activity nearing control levels, though detailed mechanism of uptake and translocation are yet to be analyzed.

Conclusion

In totality, the AgNPs prepared are safe to be discharged in the environment and possibly utilized in processes of pollution remediation. AgNPs may also be efficiently utilized in agricultural research to obtain better health of crop plants as shown by our study.
3D PS-wave imaging with elastic reverse-time migration
Authors: Du Qizhen , Gong Xufei , Zhang Mingqiang , Zhu Yitong , Fang Gang
Published: July 2014

One of the important features of elastic reverse-time migration is that it is a depth domain prestack migration method based on a vectorial wavefield. PP- and PS-wave images can be easily generated by implementing an imaging condition to pure wave modes separated with divergence and curl operators in isotropic media. In the 3D case, however, the curl calculation will generate a 3C vector S-wave, which makes it impossible to generate a scalar PS image with the crosscorrelation imaging condition. Therefore, we first analyzed the polarity distribution of a 3D S-wave and concluded that the separated S-wave keeps perpendicular to a plane determined by the particle motion direction and the propagation direction of the S-wave. This specific plane is the raypath plane when the S-wave is excited by an incident P-wave. The normal direction of the raypath plane can be calculated by computing the vector product of the propagation directions of source and receiver wavefields. Then, we used this normal direction as the reference direction of the S-wave to scalarize the S-wave. Scalarization can be achieved by assigning a positive sign if the vector S-wave is equidirectional with the reference direction or a negative sign if the vector S-wave is contradirectional with the reference direction. Additionally, the scalar S-wave has the same absolute value as the vector S-wave. Next, the P-wave and the scalar S-wave can be applied to an imaging condition to generate a scalar PS image. Numerical examples with true velocity models and those in the presence of velocity error and data noise are presented to demonstrate the potential of the proposed method.
Comparison of multifrequency selection strategies for simultaneous-source full-waveform inversion
Authors: Anagaw Amsalu Y. , Sacchi Mauricio D.
Published: July 2014

The computational cost of full-waveform inversion (FWI) is a major obstacle to estimating the velocity model for large-scale problems. One way to reduce the overall cost of waveform inversion is by adopting a simultaneous-source strategy. In other words, multiple sources are simultaneously fired to simulate supershot gathers and thereby reduce the number of seismic modeling simulations that are performed during the inversion. However, the use of simultaneous sources introduces crosstalk artifacts that arise from the interference among the sources that constitute a supershot. We analyzed the influence of different simultaneous multifrequency selection strategies on crosstalk artifacts. Our analysis focused on a frequency-domain FWI algorithm that is implemented with simultaneous sources that are randomly encoded with random time shifts. In the multiscale conventional FWI strategies, a finite set of discrete frequencies was selected and the inversion was carried out sequentially from low- to high-frequency data components. First, the long wavelength components of model parameters were recovered from the low-frequency data, and then more details and features were extracted as the inversion proceeded to the higher frequency data. We examined six frequency selection strategies and tested the performance of the algorithm with encoded data sets. Numerical tests showed that high-fidelity results could be attained by inverting partially overlapped groups of temporal frequencies. Our FWI algorithm is based on a matrix-free Gauss-Newton method. To mitigate crosstalk artifacts during the numerical inversion, a new encoding was generated at every iteration. We also found that high-resolution images can be obtained by resampling new source positions and new encoding functions at every iteration of the FWI algorithm.
Symplectic scheme and the Poynting vector in reverse-time migration
Authors: Araujo Edvaldo S. , Pestana Reynam C. , dos Santos Adriano W. G.
Published: July 2014

We developed a new numerical solution for the wave equation that combines symplectic integrators and the rapid expansion method (REM). This solution can be used for seismic modeling and reverse-time migration (RTM). In seismic modeling and RTM, spatial derivatives are usually calculated by finite differences (FDs) or by the Fourier method, and the time evolution is normally obtained by a second-order FD approach. If the spatial derivatives are computed by higher order FD schemes, then the time step needs to be small enough to avoid numerical dispersion, therefore increasing the computational time. However, by using REM with the Fourier method for the spatial derivatives, we can apply the proposed method to propagate the wavefield for larger time steps. Moreover, if the appropriate number of expansion terms is chosen, this method is unconditionally stable and propagates seismic waves free of numerical dispersion. The use of a symplectic numerical scheme provides the solution of the wave equation and its first time derivative at the current time step. Thus, the Poynting vector can also be computed during the time extrapolation process at very low computational cost. Based on the Poynting vector information, we also used a new methodology to separate the wavefield in its upgoing and downgoing components. Additionally, Poynting vector components can be used to compute common gathers in the reflection angle domain, and the stack of some angle gathers can be used to eliminate low-frequency noise produced by the RTM imaging condition. We numerically evaluated the applicability of the proposed method to extrapolate a wavefield with a time step larger than the ones commonly used by symplectic methods as well as the efficiency of this new symplectic method combined with REM to successfully handle the Poynting vector calculation.
Phase retrieval through regularization for seismic problems
Authors: Gholami Ali
Published: July 2014

The most advanced data processing/imaging algorithms aim at optimizing a suitably defined cost function consisting of a data misfit term, posed in the data domain, and a regularization term. For strong phase errors in the data, however, such algorithms fail to achieve an acceptable solution because they force us to match the incorrect phase information. To remedy this deficiency, we replaced the time domain misfit term by a Fourier magnitude fidelity term to recover the desired signal from just the amplitude spectrum of the observations. Such a problem is known as phase retrieval, and it is a subject of interest for those who cannot measure the phase information about the system under study. The proposed phase retrieval problem is solved by a fast iterative shrinkage/thresholding algorithm, and it is used to tackle two common phase problems arising in seismic processing: data recovery in the presence of residual static shifts and deconvolution with a missing wavelet phase. Under sparsity constraints, both problems can be solved using just the amplitude spectrum of the observed data. In both cases, using computer-simulated data and field data, the regularized phase retrieval algorithm was able to obtain better results than the conventional methods in which the misfit term is posed in the time domain.
An algorithm adapting encoded simultaneous-source full-waveform inversion to marine-streamer acquisition data
Authors: Son Woohyun , Pyun Sukjoon , Shin Changsoo , Kim Han-Joon
Published: July 2014

In recent years, the encoded simultaneous-source full-waveform inversion (ESSFWI) algorithm, which can reduce the computational cost of the individual-source full-waveform inversion (FWI), has been studied by many researchers. Although the ESSFWI technique can be successfully applied to fixed-spread acquisition data, the application of this technique to marine-streamer data is difficult because of the acquisition geometry. The difference in the acquisition geometry between the observed and modeled data produces missing trace parts in a stacked seismogram and unwanted events in the residual seismogram. To avoid these unwanted residuals, the correlation-based ESSFWI technique has been suggested by several researchers. However, the correlation-based approach unpredictably modifies the residual seismograms, which may result in distortion of the inverted velocity model. We developed an alternative approach to properly cope with the acquisition geometry problem. Our algorithm modified the offset-limited observed data to full-offset data by combining the original observed data with the modeled data. This modification led to an undistorted residual seismogram for the simultaneous multiple shot data. However, if we applied this modification process at every iteration of the inversion, the computational cost increased. To accelerate our ESSFWI algorithm, we proposed a strategy that modified the observed data at the iterations corresponding to the square numbers. Through the numerical examples, we discovered that our ESSFWI strategy better described the velocity structure of Marmousi-2 model than the correlation-based approach. Based on the comparison of computational speed-up for several strategies, we also confirmed that our ESSFWI algorithm using square numbers was a reasonable strategy. An example using real data found that our algorithm is slightly sensitive to noise, but we could minimize this sensitivity to noise by using a reasonable strategy to reduce the problem of missing traces. As a result, we could perform an effective ESSFWI even for marine-streamer acquisitions.
Fresnel volume and interface Fresnel zone for reflected and transmitted waves from a curved interface in anisotropic media
Authors: Ursin Bjørn , Favretto-Cristini Nathalie , Cristini Paul
Published: July 2014

The Fresnel volume and the interface Fresnel zone (IFZ) concepts play an important role in seismic exploration because the IFZ largely contributes to the formation of the reflection and transmission wavefields at an observation point. We derived analytic expressions based on traveltime approximations to evaluate the IFZ size for converted and nonconverted waves reflected (or transmitted) by a curved interface between two homogeneous general anisotropic media, and more specifically for dip-constrained transversely isotropic homogeneous media. The reflectors are of anticline, syncline, or saddle type, and their principal curvature axes may not lie in the incidence plane. As in an anisotropic medium the isochron in most cases assumes a nonelliptical shape, the size and the shape of the IFZ for reflected waves are predominantly dependent on the curvatures of the isochrons together with the curvatures of the interface. The IFZ shapes also exhibit large variation with interface curvature and incidence angle. In addition, the difference between the Thomsen anisotropy parameters [Formula: see text] and [Formula: see text] is found to control the size of the IFZ for P-P and P-S reflections. The IFZ for anisotropic media with curved interface can be much larger than that for equivalent isotropic media, and more specifically for positive values of [Formula: see text]. The spatial resolution of unmigrated seismic data in anisotropic media would consequently be different from that determined for the same configuration for isotropic models and a planar interface.
Using cylindrical surface-based curvature change rate to detect faults and fractures
Authors: Yu Jingbo
Published: July 2014

Surface-shape-related and seismic discontinuity attributes are two different ways to delineate faults and fractures, such as curvature and coherence. These two categories of attributes have their respective advantages, depending on the seismic data, in characterizing faults and fractures. Curvature falls into the former category, and it is powerful and popular for predicting fracture densities. Another use of curvature is identifying and mapping individual faults and fractures; in this case, a quadratic surface is used for fitting the faulted horizon in a least-squares sense. But the surface shape of a faulted horizon is closer to a cylindrical surface with a cubic curve as its directrix, rather than a quadratic one, which implies that we have an opportunity of using a higher order derivative to reveal more subtle faults and fractures. I prepared a cylindrical surface-based algorithm as an aid to delineate faults and fractures. This method made use of estimates of curvature change rate and took cylindrical surface into account, and it improved delineations of faults and fractures. The applications of the new attribute demonstrated that it can detect more subtle faults and fractures than traditional seismic curvatures, especially for characterizing faults with small throws, while it smears quadratic features, such as a fold on a local scale, a dome, etc. So, the new attribute is a more targeted approach for delineating faults and fractures.
Reducing the computer memory requirement for 3D reverse-time migration with a boundary-wavefield extrapolation method
Authors: Tan Sirui , Huang Lianjie
Published: July 2014

Reverse-time migration (RTM) using the crosscorrelation imaging condition requires that the forward-propagated source wavefield and the backward-propagated receiver wavefield be accessible within the imaging domain at the same time step. There are two categories of methods to balance the computer memory requirement and the computational complexity of RTM: checkpointing methods and source-wavefield reconstruction methods. We have developed a new source-wavefield reconstruction method to improve the balance between the computer memory requirement and the computational complexity of RTM. During the forward simulation of the source wavefield, we stored boundary wavefields only at one or two layers of spatial grid points and reconstructed the back-propagated source wavefield at the same time step as that of the back-propagated receiver wavefield, using a high-order wave-equation extrapolation scheme. One conventional RTM method uses boundary wavefields stored at multiple layers of spatial grid points and a high-order finite-difference (FD) scheme to reconstruct the back-propagated source wavefield. For an FD scheme with the eighth or sixteenth order of accuracy in space, our new method used only 37.5% of the computer memory required by this conventional method to store the boundary wavefields. This reduction of computer memory usage is significant because storing the boundary wavefields consumes most of the computer memory required for 3D migration using reconstructed source wavefields. Moreover, our method maintained the spatial order of accuracy of the FD scheme for the entire imaging domain, whereas some conventional methods reduce the spatial-order accuracy of the FD scheme near the boundaries to back-propagate the source wavefield to decrease the computer memory requirement. We validated our method using synthetic seismic data. Our method produced 2D and 3D migration images of complex subsurface structures as accurate as those yielded using an RTM method without reducing the spatial order of accuracy near the boundaries.
Narrating “White Slavery!” In The Wire: A Generic Genealogy
Authors: Murphy Laura T.
Published: July 2014

Home Box Office's The Wire is a cop show that boldly seeks to explore the tensions in the grand narratives that we brought with us into the twenty-first century—mythologies regarding the safety our state can provide us, the postracial society many thought we had built in the United States, the stability of the United States as a superpower, our unshakable economy, the undeniability of social mobility, our unlimited individual potential, our pursuit of the true and the good. Focusing specific attention on the representation of modern slavery in season 2, Laura Murphy locates The Wire in a long tradition of representing slavery that can further inform our reading of the program's interrogation of early twenty-first-century American life, cultures, and literary traditions. Read in the context of two modes of representing slavery in particular—the African American slave narrative tradition and the “white slavery” narratives of the early twentieth century—The Wire becomes an inheritor of and contributor to our ever-changing picture of slavery in the United States and the cultural norms and anxieties that allow it to exist. This article traces some of the cultural contexts that inform the depiction of slavery in the last few centuries of American writing as a way of historicizing and critiquing the way The Wire takes up slavery as its subject in the twenty-first century. This reading reveals the deep-rooted and persistent cultural anxieties regarding race, ethnicity, and sex that intersect in our discourse on forced sex work, a troubling discourse that is alternatingly highlighted by the program and inadvertently replicated.
The Secret History of Sprawl: Joyce Carol Oates'sExpensive Peopleand the Deterritorialization of Suburbia
Authors: Reynolds Andrew
Published: July 2014

American postwar suburbanization is rarely—if ever—discussed through the rhetorics of postmodernism and globalization. The suburban novel genre contributes to the view of the suburbs as detached from such sweeping historical developments. Indeed the characteristic discontent found throughout suburban narratives stems from feelings of isolation and detachment. Joyce Carol Oates's novel provides an opportunity to rethink the relationship between supposedly private, domestic problems and public history. Through allusions to the Detroit riot of 1967 and the Vietnam War, Expensive People suggests an unusual connection between the public violence of these late-sixties conflicts, on the one hand, and the protagonist's “disintegration” and his mother's mysterious death—the ultimate products of their suburban discontent—on the other. This connection can be elaborated through the concepts of sprawl and deterritorialization, which help explain how the same racist, expansionist, capitalist agenda that has harmed the populations of inner-city Detroit and rural Vietnam can simultaneously benefit affluent white suburbanites. Expensive People should thus be read as a historiographical metafiction that satirizes the suburban genre, questioning the assumption that detachment and discontent go hand in hand in the American suburbs.
Theoretical Study of the π → π* Excited States of Oligoacenes: A Full π-Valence DMRG-CASPT2 Study
Authors: Kurashige Yuki , Yanai Takeshi
Published: July 2014

The energy levels of low-lying π → π* excited states of oligoacenes, anthracene to hexacene, were studied by using the DMRG-CASPT2 method with a full π-valence complete active space. The effects of the size of active space, truncations of the renormalized basis in the DMRG algorithm, and the structural relaxation were also examined.
Shark fisheries in the Southeast Pacific: A 61-year analysis from Peru
Authors: Gonzalez-Pestana Adriana , Kouri J. Carlos , Velez-Zuazo Ximena
Published: July 2014

Peruvian waters exhibit high conservation value for sharks. This contrasts with a lag in initiatives for their management and a lack of studies about their biology, ecology and fishery. We investigated the dynamics of Peruvian shark fishery and its legal framework identifying information gaps for recommending actions to improve management. Further, we investigated the importance of the Peruvian shark fishery from a regional perspective. From 1950 to 2010, 372,015 tons of sharks were landed in Peru. From 1950 to 1969, we detected a significant increase in landings; but from 2000 to 2011 there was a significant decrease in landings, estimated at 3.5% per year. Six species represented 94% of landings: blue shark (Prionace glauca), shortfin mako (Isurus oxyrinchus), smooth hammerhead (Sphyrna zygaena), common thresher (Alopias vulpinus), smooth-hound (Mustelus whitneyi) and angel shark (Squatina californica). Of these, the angel shark exhibits a strong and significant decrease in landings: 18.9% per year from 2000 to 2010. Peru reports the highest accumulated historical landings in the Pacific Ocean; but its contribution to annual landings has decreased since 1968. Still, Peru is among the top 12 countries exporting shark fins to the Hong Kong market. Although the government collects total weight by species, the number of specimens landed as well as population parameters (e.g. sex, size and weight) are not reported. Further, for some genera, species-level identification is deficient and so overestimates the biomass landed by species and underestimates the species diversity. Recently, regional efforts to regulate shark fishery have been implemented to support the conservation of sharks but in Peru work remains to be done
Cloud Implications on Software Network Structure and Security Risks
Authors: August Terrence , Niculescu Marius Florin , Shin Hyoduk
Published: July 2014

By software vendors offering, via the cloud, software-as-a-service (SaaS) versions of traditionally on-premises application software, security risks associated with usage become more diversified. This can greatly increase the value associated with the software. In an environment where negative security externalities are present and users make complex consumption and patching decisions, we construct a model that clarifies whether and how SaaS versions should be offered by vendors. We find that the existence of version-specific security externalities is sufficient to warrant a versioned outcome, which has been shown to be suboptimal in the absence of security risks. In high security-loss environments, we find that SaaS should be geared to the middle tier of the consumer market if patching costs and the quality of the SaaS offering are high, and geared to the lower tier otherwise. In the former case, when security risk associated with each version is endogenously determined by consumption choices, strategic interactions between the vendor and consumers may cause a higher tier consumer segment to prefer a lower inherent quality product. Relative to on-premises benchmarks, we find that software diversification leads to lower average security losses for users when patching costs are high. However, when patching costs are low, surprisingly, average security losses can increase as a result of SaaS offerings and lead to lower consumer surplus. We also investigate the vendor’s security investment decision and establish that, as the market becomes riskier, the vendor tends to increase investments in an on-premises version and decrease investments in a SaaS version. On the other hand, in low security-loss environments, we find that SaaS is optimally targeted to a lower tier of the consumer market, average security losses decrease, and consumer surplus increases as a result. Security investments increase for both software versions as risk increases in these environments.
Approximate Dynamic Programming for a Class of Long-Horizon Maritime Inventory Routing Problems
Authors: Papageorgiou Dimitri J. , Cheon Myun-Seok , Nemhauser George , Sokol Joel
Published: July 2014

We study a deterministic maritime inventory routing problem with a long planning horizon. For instances with many ports and many vessels, mixed-integer linear programming (MIP) solvers often require hours to produce good solutions even when the planning horizon is 90 or 120 periods. Building on the recent successes of approximate dynamic programming (ADP) for road-based applications within the transportation community, we develop an ADP procedure to generate good solutions to these problems within minutes. Our algorithm operates by solving many small subproblems (one for each time period) and by collecting information about how to produce better solutions. Our main contribution to the ADP community is an algorithm that solves MIP subproblems and uses separable piecewise linear continuous, but not necessarily concave or convex, value function approximations and requires no off-line training. Our algorithm is one of the first of its kind for maritime transportation problems and represents a significant departure from the traditional methods used. In particular, whereas virtually all existing methods are “MIP-centric,” i.e., they rely heavily on a solver to tackle a nontrivial MIP to generate a good or improving solution in a couple of minutes, our framework puts the effort on finding suitable value function approximations and places much less responsibility on the solver. Computational results illustrate that with a relatively simple framework, our ADP approach is able to generate good solutions to instances with many ports and vessels much faster than a commercial solver emphasizing feasibility and a popular local search procedure.
A Chemotaxonomic Study in the Genus Zingiber
Authors: MARSUSI MARSUSI , SETYAWAN AHMAD DWI , LISTYAWATI SHANTI
Published: July 2014

Zingiber is profitable for spice, ingredients, medicine and garnishing plant (Purseglove, 1972). The systematic ofZingiber (and other Zingiberaceae) has been argued among the authors, because they commonly use the morphological and the anatomical characters, that they obtain limited data. The chemical constituents of volatile oils are one of the most prospective characters for taxonomy of Zingiber. This research is objected to find out (1) the constituents of volatile oils (2) the number and the type of compounds composing volatile and (3) the genetic relationship. This research is done in the laboratory. The data seeking covers, i.e. (1) water distillation (Guenther, 1948; Anon, 1977), (2) extraction (Anon, 1977; Harborne, 1984), and gas chromatography (Mc Nair & Bonelli, 1968;Pramono, 1988). Dendrogram is arranged referring to Sokal & Sneath (1963), and the association coefficient degrees are determined referring to Pielou (1984). The rhizomes are gathered from Bogor Botanical Garden and from around Surakarta. There are seven achieved species, namely Z. amaricans Nor., Z. aromaticum Val., Z. cassumunar Roxb.,Z. gramineum Bl., Z. officinale Roxb., Z. ottensii Val., and Z. zerumbet (L.) J.E. Smith. Every species is identified referring to manuals of Backer & Bakhuizen van den Brink (1968), Holttum (1950) and Burkill (1935). The volatile contents of seven species subsequently are 4.67% (ml/100gr.), 5.00%, 6.33%, 0.20%, 6.67%, 4.29% and 6.00%. The numbers of composing volatile compounds subsequently are 30, 26, 37, 44, 29, 29 and 29. The genetic relationships of seven species are Z. amaricans, Z. aromaticum and Z. zerumbet joint at similarity index of 90, and it is followed by Z. ottensii at similarity index of 85. Then those five species join with Z. cassumunar and Z. gramineum at similarity index of 60. The last is the joining of Z. officinale to those six species at similarity index of 55.Â© 2001 Jurusan Biologi FMIPA UNS SurakartaKeywords: chemotaxonomy, volatile oils, Zingiber.
Evaluation of palatability, protein and energi consumtion of adult lizard (Mabouya multifasciata) by feed them of with many diet variations
Authors: RIDWAN RONI , NAHROWI NAHROWI , SOFYAN Hj. LILY AMALIA
Published: July 2014

Lizard (Mabouya multifasciata), one of natural resources that spreads almost all Indonesian islands. The animals can potentially be used as a source of protein and medicine as well as a pet. The objectives of the research were therefore to investigate the preference of certain kind of diet, measure the protein and energy consumption, and also to observe the weight gain of the lizard. Seventy two lizards consisting of 36 females that each having weight of 29.7 + 2.6 grams and 36 male that having weight of 30.0 + 2.9 grams were used in this study. These lizards were captured from their wild nature around Bogor, Ciamis, Sumedang and Cianjur of West Java. Blockexperimental design was used, with 4 diet treatments and two grouping based on sex, (male and female). The diets were crickets, mealworm, red ant larva and artificial diet. Each tree lizards was put on 0.30m x 0.30m x 0.50m nets made from glass. Diets were given 3% dry matter of lizard body weight and water has given ad libitum. Parameter measured was dry matter consumption, protein consumption, energy consumption and body weight gain. ANOVA used for the data analysis, followed with Duncan range-test. The result showed that dry matter consumption of crickets, red ant larva and artificial diet was significantly (P<0.01) higher than mealworms. Consumption of crickets crude-protein was significantly (P<0.01) higher than mealworms, red ant larva and artificial diet. Mealworm crude-protein consumption was significantly (P<0.01) lower compared with both red ant larva and artificial diet. Crickets and red ant larva showed higher affect (P<0.01) on body weight gain thanartificial diet. However, there were no significant effect of all diet on consumption, brute energy and relatively metabolic energy. Grouping based on sex also did not show any significant affect to all parameters observed. It can be concluded that lizards prefer eating crickets, red ant larva and diet than mealworms.Â© 2001 Jurusan Biologi FMIPA UNS SurakartaKeywords: feeding variants, palatability, protein, energy consumption, lizard.