bluuebunny/crossref_metadata_2025 huggingface dataset:
Modified MR dispersion imaging in prostate dynamic contrast‐enhanced MRI
Authors: Sung Kyunghyun
Published: February 2019

Background

An estimation of an intravascular dispersion parameter was previously proposed to improve the overall accuracy and precision of the model parameters, but the high computation complexity can limit its practical usability in prostate dynamic contrast‐enhanced MRI (DCE‐MRI).

Purpose

To compare and evaluate the model fitting uncertainty and error in the model parameter estimation using different DCE‐MRI analysis models and to evaluate the ability of the intravascular dispersion parameter to delineate between noncancerous and cancerous prostate tissue in the transition and peripheral zones.

Study Type

Retrospective.

Population

Fifty‐three patients who underwent radical prostatectomy.

Field Strength/Sequence

3 T/3D RF‐spoiled gradient echo sequence.

Assessment

The coefficient of variation was used to assess the model fitting uncertainty by adding random noise to the time–concentration curves, and the Akaike information criterion was used to assess the model fitting error. The parametric maps derived from four DCE‐MRI analysis models were evaluated by evaluating the delineation between noncancerous tissue and prostate cancer or clinically significant prostate cancer.

Statistical Tests

The receiver operating curve analysis was performed to compare the ability to delineate between noncancerous and prostate cancer tissue in the transition and peripheral zones.

Results

Both MR dispersion imaging (MRDI) and Weinmann analysis models had the maximum coefficient of variation in different tissue types, while the model fitting uncertainty of modified (m)MRDI was similar to the standard Toft model. In mMRDI, the model fitting error was minimum, and the delineation between noncancerous and clinically significant prostate cancer tissue was improved in both transition (area under the curve [AUC] = 0.92) and peripheral zones (AUC = 0.92), in comparison with MRDI (AUC = 0.89 and AUC = 0.85, respectively).

Data Conclusion

The mMRDI showed promising results in detecting prostate cancer while maintaining a similar model fitting uncertainty.

Level of Evidence: 3

Technical Efficacy: Stage 1

J. Magn. Reson. Imaging 2019;50:1307–1317.
Variation in cardiovascular magnetic resonance myocardial contouring: Insights from an international survey
Authors: Moody William E. , Hudsmith Lucy E. , Holloway Ben , Treibel Thomas A. , Davies Rhodri , Kozor Rebecca , Hamilton‐Craig Christian , Edwards Nicola C. , Bradlow William M. , Moon James C. , Steeds Richard P. ,   On behalf of the British Society of Cardiovascular Magnetic Resonance and the Australia and New Zealand Working Group for Cardiovascular Magnetic Resonance
Published: February 2019

Level of Evidence: 5

Technical Efficacy Stage: 2

J. Magn. Reson. Imaging 2019;50:1336–1338.
Optimization and repeatability of multipool chemical exchange saturation transfer MRI of the prostate at 3.0 T
Authors: Evans Vincent Stephen , Torrealdea Francisco , Rega Marilena , Brizmohun Appayya Mrishta , Latifoltojar Arash , Sidhu Harbir , Kim Mina , Kujawa Aaron , Punwani Shonit , Golay Xavier , Atkinson David
Published: February 2019

Background

Chemical exchange saturation transfer (CEST) can potentially support cancer imaging with metabolically derived information. Multiparametric prostate MRI has improved diagnosis but may benefit from additional information to reduce the need for biopsies.

Purpose

To optimize an acquisition and postprocessing protocol for 3.0 T multipool CEST analysis of prostate data and evaluate the repeatability of the technique.

Study Type

Prospective.

Subjects

Five healthy volunteers (age range: 24–47 years; median age: 28 years) underwent two sessions (interval range: 7–27 days; median interval: 20 days) and two biopsy‐proven prostate cancer patients were evaluated once. Patient 1 (71 years) had a Gleason 3 + 4 transition zone (TZ) tumor and patient 2 (55 years) had a Gleason 4 + 3 peripheral zone (PZ) tumor.

Field Strength

3.0 T. Sequences run: T2‐weighted turbo‐spin‐echo (TSE); diffusion‐weighted imaging; CEST; WASABI (for B0 determination).

Assessment

Saturation, readout, and fit‐model parameters were optimized to maximize in vivo amide and nuclear Overhauser effect (NOE) signals. Repeatability (intrasession and intersession) was evaluated in healthy volunteers. Subsequently, preliminary evaluation of signal differences was made in patients. Regions of interest were drawn by two post‐FRCR board‐certified readers, both with over 5 years of experience in multiparametric prostate MRI.

Statistical Tests

Repeatability was assessed using Bland–Altman analysis, coefficient of variation (CV), and 95% limits of agreement (LOA). Statistical significance of CEST contrast was calculated using a nonparametric Mann–Whitney U‐test.

Results

The optimized saturation scheme was found to be 60 sinc‐Gaussian pulses with 40 msec pulse duration, at 50% duty‐cycle with continuous‐wave pulse equivalent B1 power (B1CWPE) of 0.92 μT. The magnetization transfer (MT) contribution to the fit‐model was centered at –1.27 ppm. Intersession coefficients of variation (CVs) of the amide, NOE, and magnetization transfer (MT) and asymmetric magnetization transfer ratio (MTRasym) signals of 25%, 23%, 18%, and 200%, respectively, were observed. Fit‐metric and MTRasym CVs agreed between readers to within 4 and 10 percentage points, respectively.

Data Conclusion

Signal differences of 0.03–0.10 (17–43%) detectable depending upon pool, with MT the most repeatable (signal difference of 17–22% detectable).

Level of Evidence: 2

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;50:1238–1250.
New insights into the degradation mechanism of cellulose nitrate in cinematographic films by Raman microscopy
Authors: Neves Artur , Angelin Eva Mariasole , Roldão Élia , Melo Maria João
Published: February 2019

The degradation of cellulose nitrate cinematographic films stored inside an aluminum can was studied by infrared spectroscopy and Raman microscopy. Cellulose nitrate image heritage is strongly susceptible to degradation, being a major conservation challenge. Infrared spectroscopy has been the traditional technique in the assessment of the polymer degradation, but new in situ diagnostic tools to monitor the initial stages of degradation are needed. In this work, cellulose nitrate films were produced and irradiated as aging references to understand how chemical changes were observed in Raman spectroscopy. In comparison with infrared spectroscopy, this technique confirmed the mechanisms proposed in the literature and, at advanced stages of degradation, provided new relevant information detecting an intense peak at 1046 cm−1 associated to nitric acid. Comparing these results with the cinematographic films, it was observed that the plasticizers, which identification was more straightforward using Raman microscopy, have contributions in the regions were chemical changes occur, making it difficult to draw conclusions. Nevertheless, nitric acid and silver nitrate peaks were found in Raman spectra confirming the unstable and noxious environment inside de aluminum can and proving that Raman microscopy can be a valuable complementary in situ technique for cellulose nitrate degradation studies.
Off‐axis response due to mechanical coupling across all six degrees of freedom in the human disc
Authors: DeLucca John F. , Amin Dhara , Peloquin John M. , Vresilovic Edward J. , Costi John J. , Elliott Dawn M.
Published: February 2019

The kinematics of the intervertebral disc are defined by six degrees of freedom (DOF): three translations (Tz: axial compression, Tx: lateral shear, and Ty: anterior‐posterior shear) and three rotations (Rz: torsion, Rx: flexion‐extension, and Ry: lateral bending). There is some evidence that the six DOFs are mechanically coupled, such that loading in one DOF affects the mechanics of the other five “off‐axis” DOFs, however, most studies have not controlled and/or measured all six DOFs simultaneously. Additionally, the relationships between disc geometry and disc mechanics are important for evaluation of data from different sized donor and patient discs. The objectives of this study were to quantify the mechanical behavior of the intervertebral disc in all six degrees of freedom (DOFs), measure the coupling between the applied motion in each DOF with the resulting off‐axis motions, and test the hypothesis that disc geometry influences these mechanical behaviors. All off‐axis displacements and rotations were significantly correlated with the applied DOF and were of similar magnitude as physiologically relevant motion, confirming that off‐axis coupling is an important mechanical response. Interestingly, there were pairs of DOFs that were especially strongly coupled: lateral shear (Tx) and lateral bending (Ry), anterior‐posterior shear (Ty) and flexion‐extension (Rx), and compression (Tz) and torsion (Rz). Large off‐axis shears may contribute to injury risk in bending and flexion. In addition, the disc responded to shear (Tx, Ty) and rotational loading (Rx, Ry, and Rz) by increasing in disc height in order to maintain the applied compressive load. Quantifying these mechanical behaviors across all six DOF are critical for designing and testing disc therapies, such as implants and tissue engineered constructs, and also for validating finite element models.
Hybrid, phase–fitted, four–step methods of seventh order for solving x″(t) = f(t,x)
Authors: Medvedev Maxim A. , Simos T. E. , Tsitouras Ch.
Published: February 2019

A four‐step method of seventh algebraic order is presented. It is tuned for addressing the special second order initial value problem. The new method is hybrid, explicit, and uses three stages per step. In addition is phase fitted. In consequence it uses variable coefficients that depend on the magnitude of the step‐size. We also present numerical tests on a set of standard problems that illustrate the efficiency of the derived method over older ones given in the relevant literature.
DFT computational schemes for 15N NMR chemical shifts of the condensed nitrogen‐containing heterocycles
Authors: Semenov Valentin A. , Samultsev Dmitry O. , Krivdin Leonid B.
Published: February 2019

A systematic density functional theory (DFT) study of the accuracy factors (functionals, basis sets, and solvent effects) for the computation of 15N NMR chemical shifts has been performed in the series of condensed nitrogen‐containing heterocycles. The behavior of the most representative functionals was examined based on the benchmark calculations of 15N NMR chemical shifts in the reference set of compounds. It was found that the best agreement with experiment was achieved with OLYP functional in combination with aug‐pcS‐3(N)//pc‐2 locally dense basis set scheme providing mean absolute error of 5.2 ppm in the range of about 300 ppm. Taking into account solvent effects was performed within a general Tomasi's polarizable continuum model scheme. It was also found that computationally demanding supermolecular solvation model computations essentially improved some “difficult” cases, as was illustrated with phenanthroline dissolved in methanol. Based on the performed calculations, some 200 unknown 15N NMR chemical shifts were predicted with a high level of confidence for about 50 real‐life condensed nitrogen‐containing heterocycles, which could serve as a practical guide in structural elucidation of this class of compounds.
Measurement of synovial tissue volume in knee osteoarthritis using a semiautomated MRI‐based quantitative approach
Authors: Perry Thomas A. , Gait Andrew , O’Neill Terence W. , Parkes Matthew J. , Hodgson Richard , Callaghan Michael J. , Arden Nigel K. , Felson David T. , Cootes Timothy F.
Published: February 2019

Purpose

Synovitis is common in knee osteoarthritis and is associated with both knee pain and progression of disease. Semiautomated methods have been developed for quantitative assessment of structure in knee osteoarthritis. Our aims were to apply a novel semiautomated assessment method using 3D active appearance modeling for the quantification of synovial tissue volume (STV) and to compare its performance with conventional manual segmentation.

Methods

Thirty‐two sagittal T1‐weighted fat‐suppressed contrast‐enhanced MRIs were assessed for STV by a single observer using 1) manual segmentation and 2) a semiautomated approach. We compared the STV analysis using the semiautomated and manual segmentation methods, including the time taken to complete the assessments. We also examined the reliability of STV assessment using the semiautomated method in a subset of 12 patients who had participated in a clinical trial of vitamin D therapy in knee osteoarthritis.

Results

There was no significant difference in STV using the semiautomated quantitative method compared to manual segmentation, mean difference = 207.2 mm3 (95% confidence interval −895.2 to 1309.7). The semiautomated method was significantly quicker than manual segmentation (18 vs. 71 min). For the semiautomated method, intraobserver agreement was excellent (intraclass correlation coefficient (3,1) = 0.99) and interobserver agreement was very good (intraclass correlation coefficient (3,1) = 0.83).

Conclusion

We describe the application of a semiautomated method that is accurate, reliable, and quicker than manual segmentation for assessment of STV. The method may help increase efficiency of image assessment in large imaging studies and may also assist investigation of treatment efficacy in knee osteoarthritis.
Game of protocols: Is QUIC ready for prime time streaming?
Authors: Arisu Sevket , Yildiz Ertan , Begen Ali C.
Published: February 2019

Quick User Datagram Protocol (UDP) Internet Connections (QUIC) is an experimental and low‐latency transport protocol proposed by Google, which is still being improved and specified in the Internet Engineering Task Force (IETF). The viewer's quality of experience (QoE) in HTTP adaptive streaming (HAS) applications may be improved with the help of QUIC's low‐latency, improved congestion control, and multiplexing features. We measured the streaming performance of QUIC on wireless and cellular networks in order to understand whether the problems that occur when running HTTP over TCP can be reduced by using HTTP over QUIC. The performance of QUIC was tested in the presence of network interface changes caused by the mobility of the viewer. We observed that QUIC resulted in quicker start of media streams, better streaming, and seeking experience, especially during the higher levels of congestion in the network and had a better performance than TCP when the viewer was mobile and switched between the wireless networks. Furthermore, we measured QUIC's performance in an emulated network that had a various amount of losses and delays to evaluate how QUIC's multiplexing feature would be beneficial for HAS applications. We compared the performance of HAS applications using multiplexing video streams with HTTP/1.1 over multiple TCP connections to HTTP/2 over one TCP connection and to QUIC over one UDP connection. To that effect, we observed that QUIC provided better performance than TCP on a network that had large delays. However, QUIC did not provide a significant improvement when the loss rate was large. Finally, we analyzed the performance of the congestion control mechanisms implemented by QUIC and TCP, and tested their ability to provide fairness among streaming clients. We found that QUIC always provided fairness among QUIC flows, but was not always fair to TCP.
Microwave Absorption in 2D Topological Insulators with a Developed Edge States Network
Authors: Mahmoodian Mahmood M. , Entin Matvey V.
Published: February 2019

A 2D HgTe quantum well is analyzed based on the assumption that the width fluctuations convert the system to a random mixture of domains with positive and negative energy gaps. The borders between ordinary and topological insulator phases form a network of the edge states covering the entire sample. The optical transitions within the edge states yield a 2D absorption. The qualitative consideration is based on the model of optical intraedge transitions in curved edge states together with percolation arguments.
First‐principles studies of lithium adsorption and diffusion on silicene with grain boundaries
Authors: Wang Xiao , Liu Huazhong , Huttula Marko , Luo Youhua , Zhang Meng , Cao Wei
Published: February 2019

As a close relative to graphene, silicene is advanced in high lithium capacity, yet attracting various manipulation strategies to promote its role in energy storage. Following grain boundary (GB) engineering route as widely used in graphene studies, in this work, first‐principles calculations were performed to investigate adsorption and diffusion behaviors of lithium on silicene with GBs of 4|8 or 5|5|8 defects. In both GB forms, donation of the Li 2s electron to the GBs significantly increases the Li adsorption energy, whereas small energy barriers facilitate the Li migration on the silicene surface. Furthermore, the large hole of GB(4‐8) also permits easy penetration of the Li ions through the defective silicene sieve. These important features demonstrate GBs are beneficial for enhancing capacity and charge speed of the Li batteries. Thus, superior anodes made of silicene with GBs are expected to serve a key solution for future energy storages.
Localization of malonyl and acetyl on substituted saikosaponins according to the full‐scan mass spectra and the fragmentation of sodium‐adduct ions in the positive mode
Authors: Liu Guoqiang , Zhang Zunjian , Lv Xiaoqing , Zhan Shuyu , Ding Baoue , Yang Xinji , Zhu Qifeng
Published: February 2019

Rationale

Discriminating between aglycone‐substituted and saccharide‐substituted saikosaponins by liquid chromatography/tandem mass spectrometry (LC/MSn) is a long‐standing issue that is still to be resolved. It is necessary to characterize the two types of substituted saikosaponins taking into consideration the potential significant difference in their bioactivity.

Methods

Taking the substituents malonyl and acetyl as examples, we developed a MS strategy to discriminate between the aglycone‐substituted and saccharide‐substituted saikosaponins through comparing their Y0 − nH2O (n = 1–2) ions from the protonated molecules in the full‐scan mass spectra and their B ions in the MS2 spectra of sodium‐adduct molecules in the positive mode.

Results

The deprotonated molecules of the aglycone‐substituted saikosaponins presented similar fragmentation patterns to those of saccharide‐substituted ones in the negative mode, which could not discriminate whether the substitutes were located on the aglycone or the saccharide. In contrast, the Y0 − nH2O (n = 1–2) ions containing or no substituent were observed respectively in the mass fragmentation of the protonated molecules of aglycone‐substituted or saccharide‐substituted saikosaponins in the positive mode. In addition, the B ions containing or no substituent were observed respectively in the mass fragmentation of the sodium‐adduct molecules of the saccharide‐substituted or aglycone‐substituted saikosaponins in the positive mode. Two aglycone‐malonylated saikosaponins were reported for the first time.

Conclusions

Whether the substituents were located on the aglycone or the saccharide could be determined according to the Y0 − nH2O (n = 1–2) ions from the protonated molecules in the full‐scan mass spectra and the B ions in the MS2 spectra of sodium‐adduct molecules in the positive mode. Our results have updated the mass fragmentation patterns of substituted saikosaponins, which is helpful for the quality control of pharmaceutical preparations containing saikosaponins. More importantly, this MS strategy should be able to be extended to characterize other substituted saponins of bioactive significance in future studies.
Gendered genetics: How reading about the genetic basis of sex differences in biology textbooks could affect beliefs associated with science gender disparities
Authors: Donovan Brian M. , Stuhlsatz Molly A. M. , Edelson Daniel C. , Buck Bracey Zoë E.
Published: February 2019

The belief that men and women differ in science ability because of genetics contributes to gender disparities in science, technology, engineering, and math (STEM) in complex ways. In this field experiment, we explored how the content of the genetics curriculum affected beliefs about science ability through its impact on a social–cognitive bias known as neurogenetic essentialism. Students (n = 460, 8th–10th grade) were randomized to read a genetics text that (a) explained plant sex differences, (b) explained human sex differences, or (c) refuted neurogenetic essentialism. After reading, students in the two genetics of sex conditions had significantly greater belief in neurogenetic essentialism and the innate basis of science ability compared with students who read the text that refuted neurogenetic essentialism. Structural equation modeling (SEM) of the experimental data demonstrated that the effect of the readings on the belief that science ability is innate was mediated by neurogenetic essentialism and this indirect effect was significant for girls but not boys. In turn, the belief that science ability is innate predicted lower future interest in STEM for girls, but not for boys. These findings suggest that learning about human genetic difference is not a socially neutral endeavor. Implications for mitigating gender disparities in STEM are discussed.
Urban freshwaters, biodiversity, and human health and well‐being: Setting an interdisciplinary research agenda
Authors: Higgins Sahran L. , Thomas Felicity , Goldsmith Ben , Brooks Stephen J. , Hassall Christopher , Harlow Julian , Stone Dave , Völker Sebastian , White Piran
Published: February 2019

The findings of a national workshop that explored the social and environmental impacts, challenges, and research opportunities associated with the role of urban freshwaters for improved public health are discussed. Bringing together the collective expertise of academics, practitioners, policy, and user‐groups from urban aquatic ecology and human health backgrounds, this commentary develops a progressive agenda for future research by synthesizing current understandings and knowledge of urban aquatic biodiversity relative to health‐related ecosystem service outcomes, from a cross‐sectoral and cross‐disciplinary perspective. Key areas include (a) a need for greater interaction between sectors to maximize opportunities for collaboration and to promote the cobenefits (both environmental and health) associated with urban freshwater ecosystems; and (b) the need for a unified understanding and operationalization of the definition of aquatic biodiversity across sectors and disciplines, to improve our understanding of whether actual freshwater biodiversity or the perception of biodiversity is important for maximizing gains in health. Methods of valuation relating to ecosystem services and resource allocation and investment in urban freshwaters are critical in ensuring that research addresses the pathways and contexts within which health and environmental benefits from blue space can be maximized.

This article is categorized under:

Human Water > Value of Water
Cover Image, Volume 6, Issue 2
Authors: Chwala Christian , Kunstmann Harald
Published: February 2019

The cover image is based on the Advanced Review Commercial microwave link networks for rainfall observation: Assessment of the current status and future challenges, by Christian Chwala and Harald Kunstmann, https://doi.org/10.1002/wat2.1337

image
Classical and quantum results on logarithmic terms in the soft theorem in four dimensions
Authors: Sahoo Biswajit , Sen Ashoke
Published: February 2019

Abstract

We explore the logarithmic terms in the soft theorem in four dimensions by analyzing classical scattering with generic incoming and outgoing states and one loop quantum scattering amplitudes. The classical and quantum results are consistent with each other. Although most of our analysis in quantum theory is carried out for one loop amplitudes in a theory of (charged) scalars interacting via gravitational and electromagnetic interactions, we expect the results to be valid more generally.
Correction to: Is the new ASNM intraoperative neuromonitoring supervision “guideline” a trustworthy guideline? A commentary
Authors: Skinner Stanley A. , Aydinlar Elif Ilgaz , Borges Lawrence F. , Carter Bob S. , Currier Bradford L. , Deletis Vedran , Dong Charles , Dormans John Paul , Drost Gea , Fernandez-Conejero Isabel , Hoffman E. Matthew , Holdefer Robert N. , Kimaid Paulo Andre Teixeira , Koht Antoun , Kothbauer Karl F. , MacDonald David B. , McAuliffe John J. , Morledge David E. , Morris Susan H. , Norton Jonathan , Novak Klaus , Park Kyung Seok , Perra Joseph H. , Prell Julian , Rippe David M. , Sala Francesco , Schwartz Daniel M. , Segura Martín J. , Seidel Kathleen , Seubert Christoph , Simon Mirela V. , Soto Francisco , Strommen Jeffrey A. , Szelenyi Andrea , Tello Armando , Ulkatan Sedat , Urriza Javier , Wilkinson Marshall
Published: February 2019

The article Is the new ASNM intraoperative neuromonitoring supervision “guideline” a trustworthy guideline? A commentary, written by Stanley A. Skinner, Elif Ilgaz Aydinlar, Lawrence F. Borges, Bob S. Carter, Bradford L. Currier, Vedran Deletis, Charles Dong, John Paul Dormans, Gea Drost, Isabel Fernandez‑Conejero, E. Matthew Hoffman, Robert N. Holdefer, Paulo Andre Teixeira Kimaid, Antoun Koht, Karl F. Kothbauer, David B. MacDonald, John J. McAuliffe III, David E. Morledge, Susan H. Morris, Jonathan Norton, Klaus Novak, Kyung Seok Park, Joseph H. Perra, Julian Prell, David M. Rippe, Francesco Sala, Daniel M. Schwartz, Martín J. Segura, Kathleen Seidel, Christoph Seubert, Mirela V. Simon, Francisco Soto, Jeffrey A. Strommen, Andrea Szelenyi, Armando Tello, Sedat Ulkatan, Javier Urriza and Marshall Wilkinson, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 05 January 2019 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 30 January 2019 to © The Author(s) 2019 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made. The original article has been corrected.
Surface and Subsurface Investigations for the Detection and Mapping of Underground Karst Cavities in MChentel Area, Cheria Basin, Northeast of Algeria
Authors: Saddek Bouhlassa , Chemseddine Fehdi , Djamel Boubaya , Nabil Bougherira
Published: February 2019

A combined approach using the surface geophysical method (microgravimetric survey) and sub-surface investigations (speleology) was undertaken at an experimental karst site located in the MChentel area near Cheria town (Northeast of Algeria). The gravimetric survey, carried out by a gravimeter GNU-KC 444 during March-April 2016, allowed the procurement of 614 gravimetric measurements distributed on the whole of the zone of study.

The gravimetric data shows a reduction in the values of the Bouguer anomaly between two collapses. This trend probably implies an effect of karstification that would explain the reduction in the values of the Bouguer anomaly while moving towards the centre of the zone of study. The results provided in this work of underground exploration by the team of speleologists from Polytechnic Nice-Sophia in 2013 and 2014 are particularly well illustrated by the topography of the cavities upstream and the real photographs, the micromorphology and the microstructures of the walls of the cavities explored.

The joint application of the microgravimetry and speleology make it possible to evaluate the advantages and effectiveness of the microgravimetry for the detection of underground cavities. This improves knowledge of the karstic system structure of Eocene carbonates in the studied area.
From Henley to Harvard at Hyderabad? (Post and Neo-) Colonialism in Management Education in India
Authors: KUMAR ARUN
Published: February 2019

Founded in 1956, the Administrative Staff College of India (ASCI) was established with the objective of professionalizing management in post-colonial India through training, research, and consultancy. It was modeled on the Administrative Staff College at Henley-on-Thames (Henley), in the United Kingdom. Like Henley, ASCI used syndicates for its management training programs. Between 1958 and 1973, ASCI received more than $1.26 million from the Ford Foundation, part of which was used to finance the development and use of the case method in ASCI’s training programs, and later more widely in its research and consultancy. This article traces the ways by which the Ford Foundation––as adominating institution––stigmatized Henley and ASCI, their institutional practices, and the wider Indian society; and legitimized the case method pioneered at the Harvard Business School. Imbricated in the Cold War’s geo-politics, Ford Foundation’s interventions in Hyderabad should be understood as part of the emergence of the United States as the dominant neo-colonial power, which required the displacement of Britain, its institutions, and their practices as the template for India’s post-colonial management institutions.
Granular surface flow on an asymmetric conical heap
Authors: Mandal Sandip , Khakhar D. V.
Published: February 2019

We carry out an experimental study of the granular surface flow of nearly monodisperse glass beads on a conical heap formed on a rough circular disc by a narrow stream of the particles from a hopper, with the pouring point displaced from the centre of the disc. During the growth phase, an axisymmetric heap is formed, which grows either by periodic avalanches or by non-periodic avalanches that occur randomly over the azimuthal location of the heap, depending on the operating conditions and system properties. The dynamics of heap growth is characterized by the variation of the heap height, angle of repose and the angular velocity of the periodic avalanche with time, for different mass flow rates from the hopper. When the base of the heap reaches the edge of the disc closest to the pouring point, the heap stops growing and a steady surface flow of particles is developed on the heap surface, with particles flowing over the edge of the disc into a collection tray. The geometry is a unique example of a granular flow on an erodible bed without any bounding side walls. The corresponding steady state geometry of the asymmetric heap is characterized by means of surface contours and angles of repose. The streamwise and transverse surface velocities are measured using high-speed video photography and image analysis for different mass flow rates. The flowing layer thickness is measured by immersing a coated needle in the flow at different positions on the mid-line of the flow. The surface angle of the flowing layer is found to be significantly smaller than the angle of repose and to be independent of the mass flow rate. The velocity profiles at different streamwise positions for different mass flow rates are found to be geometrically similar and are well described by Gaussian functions. The flowing layer thickness is calculated from a model using the measured surface velocities. The predicted values match the measured values quite well.
The evolution of public policy attitudes: comparing the mechanisms of policy support across the stages of a policy cycle
Authors: Jagers Sverker C. , Matti Simon , Nordblom Katarina
Published: February 2019

We analyse the importance of legitimacy on public policy support by comparing how drivers of public policy attitudes evolve across the policy process consisting of the input (the processes forgoing acquisition of power and the procedures permeating political decisionmaking), throughput (the inclusion of and interactions between actors in a governance system) and output (the substantive consequences of those decisions) stages. Using unique panel data through three phases of the implementation of a congestion tax in the Swedish city of Gothenburg, we find that legitimacy is indeed important in explaining policy support. Moreover, we find a lingering effect where support in one phase depends on legitimacy both in the present and in previous phases. Hence, our study takes us one step further on the road to understand the complicated dynamic mechanisms behind the interactions between policymaking, policy support, and the legitimacy and approval of politicians and political processes.
A MAGNETIC DOUBLE INTEGRAL
Authors: BROADHURST DAVID , ZUDILIN WADIM
Published: February 2019

In a recent study of how the output voltage of a Hall plate is affected by the shape of the plate and the size of its contacts, U. Ausserlechner has come up with a remarkable double integral that can be viewed as a generalisation of the classical elliptic ‘arithmetic–geometric mean (AGM)’ integral. Here we discuss transformation properties of the integral, which were experimentally observed by Ausserlechner, as well as its analytical and arithmetic features including connections with modular forms.
Seasonal Variability of Deuterium in the Upper Atmosphere of Mars
Authors: Mayyasi Majd , Clarke J. , Bhattacharyya D. , Chaufray J. Y. , Benna M. , Mahaffy P. , Stone S. , Yelle R. , Thiemann E. , Chaffin M. , Deighan J. , Jain S. , Schneider N. , Jakosky B.
Published: February 2019

Measurements by multiple Mars Atmosphere and Volatile Evolution mission instruments, obtained between November 2014 and November 2017, are analyzed to produce deuterium properties in the upper atmosphere of Mars. We show here, for the first time, the seasonal distribution and variability of D densities, temperatures, and estimated Jeans escape rates at the exobase (200 km). Within the data constraints, it is found that the variations in D properties are similar for the northern and southern hemispheres, and peak near southern summer solstice. Trends in the D Lyman‐α brightness, temperature, density, and escape rate are increasing during the beginning of the dust storm season, peak near southern summer solstice, and decrease toward the end of the dust storm season. This suggests that seasonal drivers at Mars cause deuterium in the upper atmosphere to become globally enhanced when Mars is closest to the Sun and during the Martian dust season when water is provided to the upper atmosphere by subsurface, hydrological, and dust storm dynamics.
Large‐Scale Characteristics of Flux Transfer Events on the Dayside Magnetopause
Authors: Sun T. R. , Tang B. B. , Wang C. , Guo X. C. , Wang Y.
Published: February 2019

By using global MHD simulation, we present the large‐scale characteristics of flux transfer events (FTEs) on the dayside magnetopause during periods of generic southward interplanetary magnetic field. It is revealed that FTEs can be generated both at lower and higher latitudes, and also at almost all local times. The occurrence rate of FTEs has an apparent longitudinal/latitudinal dependence, with a higher occurrence rate near noon/at lower latitudes. It is further shown that even under constant solar wind conditions, the azimuthal lengths of FTEs can have large variability, changing from as short as <1RE to as long as >10RE for different FTEs. Moreover, FTEs generated closer to the subsolar point tend to have longer extensions along their axes. These new knowledge of large‐scale properties of FTEs will improve our understanding of the solar wind‐magnetosphere interaction.
Nucleation and Arrest of Dynamic Rupture Induced by Reservoir Depletion
Authors: Buijze L. , van den Bogert P. A. J. , Wassing B. B. T. , Orlic B.
Published: February 2019

Seismic events induced by the depletion of hydrocarbon reservoirs can cause damage to housing and cause societal and economic unrest. However, the factors controlling the nucleation and size of production‐induced seismic events are not well understood. Here we used geomechanical modeling of production‐induced stresses and dynamic rupture modeling to assess the conditions controlling down‐dip rupture size. A generic model of (offset) depleting reservoir compartments separated by a fault was modeled in 2‐D using the Finite Element package DIANA FEA. Linear slip‐weakening was used to control fault friction behavior. Fault reactivation was computed in a quasi‐static analysis simulating stresses during reservoir depletion, followed by a fully dynamic analysis simulating seismic rupture. The sensitivity of reactivation and rupture size to in situ stress, dynamic friction, critical slip distance, and reservoir offset was evaluated. After reactivation, a critical fault length was required to slip before seismic instability could occur. In a subsequent fully dynamic analysis the propagation and arrest of dynamic rupture was simulated. Rupture remained mostly confined to the reservoir interval but could also propagate into the overburden and underburden or sometimes transition into a run‐away rupture. Propagation outside the reservoir interval was promoted by a critical in situ stress, a large stress drop, a small fracture energy, and no or little reservoir offset. With increasing offset (up to the reservoir thickness), reactivation was promoted but dynamic rupture size decreased.
Toward Improving Short‐Term Predictions of Fine Particulate Matter Over the United States Via Assimilation of Satellite Aerosol Optical Depth Retrievals
Authors: Kumar Rajesh , Delle Monache Luca , Bresch Jamie , Saide Pablo E. , Tang Youhua , Liu Zhiquan , da Silva Arlindo M. , Alessandrini Stefano , Pfister Gabriele , Edwards David , Lee Pius , Djalalova Irina
Published: February 2019

This study develops a new approach to improve simulations of the particulate matter of aerodynamic diameter smaller than 2.5 μm (PM2.5) in the Community Multiscale Air Quality (CMAQ) model via assimilation of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) retrievals using the Gridpoint Statistical Interpolation (GSI) system. In contrast to previous studies that only consider errors due to transport, our computation of the background error covariance matrix incorporates uncertainties in anthropogenic emissions. To understand the impact of this approach, three experiments (one background and two assimilations) are performed over the contiguous United States (CONUS) from 15 July to 14 August 2014. The background CMAQ experiment significantly underestimates both the MODIS AOD and surface PM2.5 levels. MODIS AOD assimilation pushes both the CMAQ AOD and surface PM2.5 distributions toward the observed distributions, but CMAQ still underestimates the observations. Averaged over CONUS, the two assimilation experiments with and without including the anthropogenic emission uncertainties improve the correlation coefficient between the model and independent observations of PM2.5 by ~67% and ~48%, respectively, and reduces the mean bias by ~38% and ~10%, respectively. The assimilation improves the model performance everywhere over CONUS, except the New York and Wisconsin, where CMAQ overestimates the observed PM2.5 during nighttime after assimilation likely because of overcorrection of aerosol mass concentrations by the AOD assimilation. Future work should incorporate uncertainties in other processes (biomass burning and biogenic emissions, deposition, chemistry, transport, and boundary conditions) to further enhance the value of assimilating spaceborne AOD retrievals.
Variability in Contrail Ice Nucleation and Its Dependence on Soot Number Emissions
Authors: Bier A. , Burkhardt U.
Published: February 2019

Contrail ice nucleation is mainly controlled by aircraft emissions and the atmospheric state. The nucleation rate can have a strong impact on microphysical processes, optical properties, lifetime, and, therefore, on the climate impact of contrail cirrus. We study contrail ice crystal formation offline for specified atmospheric conditions and its spatial variability in a global climate model. Assuming the standard atmosphere, above around 270 hPa (10 km) contrail ice nucleation is mainly controlled by aircraft soot number emissions and below additionally by atmospheric temperature. Parameterizing contrail ice nucleation in a global climate model, we find that in the northern extratropics contrails form frequently far away from their formation threshold. For current soot number emissions and in case of contrail formation, 90% of emitted soot particles form on average ice crystals around the cruise level and more than 70% between cruise altitudes and 300 hPa. The number of nucleated ice crystals in the extratropics decreases nearly at the same rate as soot number emissions. In contrast, in the tropics around cruise altitudes approximately 60% of contrails develop close to their formation threshold so that on average only about 50% of emitted soot particles can form ice crystals. Below, contrail formation occurs rarely and ice nucleation is reduced more strongly. Of the main air traffic areas, contrail ice nucleation is significantly limited by the atmospheric state over eastern Asia and over the southeastern United States. This limitation is enhanced during the summer months.
Centennial‐Scale SE Pacific Sea Surface Temperature Variability Over the Past 2,300 Years
Authors: Collins James A. , Lamy Frank , Kaiser Jérôme , Ruggieri Nicoletta , Henkel Susann , De Pol‐Holz Ricardo , Garreaud René , Arz Helge W.
Published: February 2019

Detailed temperature reconstructions over the past 2,000 years are important for contextualizing modern climate change. The midlatitude SE Pacific is a key region in this regard in terms of understanding the climatic linkages between the tropics and southern high latitudes. Multicentennial timescale temperature variability remains, however, poorly understood, due to a lack of long, high‐temporal‐resolution temperature records from this region and from the southern high latitudes in general. We present a unique alkenone sea surface temperature (SST) record from 44°S on the southern Chilean margin in the SE Pacific spanning the last 2,300 years at decadal resolution. The record displays relatively large changes including a cooling transition from 14 to 12.5 °C between 1,100 and 600 cal yr BP, in line with other Chile margin SST records and coeval with Antarctic cooling. This cooling is attributable to reduced Southern Ocean deep convection, driven by a late Holocene sea‐ice increase in the Weddell Sea associated with increased El‐Niño Southern Oscillation variability. Superimposed on the late Holocene cooling, we observe multicentennial timescale SST variability, including relatively cool SSTs (12.5 °C) from 950 to 500 cal yr BP, corresponding to the Medieval Climate Anomaly, and warmer SSTs (13 °C) from 500 to 200 cal yr BP, corresponding to the Little Ice Age. These oscillations may reflect either multicentennial internal variability of the Southern Ocean deep convection and/or multicentennial variability in the phasing of El‐Niño Southern Oscillation and Southern Annular Mode events.
Brief, Repetitive Floods in Coastal Cities Cause Economic Losses
Authors: Duncombe Jenessa
Published: February 2019

A case study in Annapolis is one of the first assessments of the effects of high-tide flooding on local revenue.
NASA Wants to Get Back to the Moon, and Fast
Authors: Showstack Randy
Published: February 2019

The space agency has plans for a sustainable return to the Moon.
Tuning the Fröhlich exciton-phonon scattering in monolayer MoS2
Authors: Miller Bastian , Lindlau Jessica , Bommert Max , Neumann Andre , Yamaguchi Hisato , Holleitner Alexander , Högele Alexander , Wurstbauer Ursula
Published: February 2019

Charge carriers in semiconducting transition metal dichalcogenides possess a valley degree of freedom that allows for optoelectronic applications based on the momentum of excitons. At elevated temperatures, scattering by phonons limits valley polarization, making a detailed knowledge about strength and nature of the interaction of excitons with phonons essential. In this work, we directly access exciton-phonon coupling in charge tunable single layer MoS2 devices by polarization resolved Raman spectroscopy. We observe a strong defect mediated coupling between the long-range oscillating electric field induced by the longitudinal optical phonon in the dipolar medium and the exciton. This so-called Fröhlich exciton phonon interaction is suppressed by doping. The suppression correlates with a distinct increase of the degree of valley polarization up to 20% even at elevated temperatures of 220 K. Our result demonstrates a promising strategy to increase the degree of valley polarization towards room temperature valleytronic applications.
A large CRISPR-induced bystander mutation causes immune dysregulation
Authors: Simeonov Dimitre R. , Brandt Alexander J. , Chan Alice Y. , Cortez Jessica T. , Li Zhongmei , Woo Jonathan M. , Lee Youjin , Carvalho Claudia M. B. , Indart Alyssa C. , Roth Theodore L. , Zou James , May Andrew P. , Lupski James R. , Anderson Mark S. , Buaas F. William , Rokhsar Daniel S. , Marson Alexander
Published: February 2019

A persistent concern with CRISPR-Cas9 gene editing has been the potential to generate mutations at off-target genomic sites. While CRISPR-engineering mice to delete a ~360 bp intronic enhancer, here we discovered a founder line that had marked immune dysregulation caused by a 24 kb tandem duplication of the sequence adjacent to the on-target deletion. Our results suggest unintended repair of on-target genomic cuts can cause pathogenic “bystander” mutations that escape detection by routine targeted genotyping assays.
Unique crystal field splitting and multiband RKKY interactions in Ni-doped EuRbFe4As4
Authors: Xu Chenchao , Chen Qijin , Cao Chao
Published: February 2019

The relationship between magnetism and superconductivity has been one of the most discussed topics in iron-based superconductors. Using first-principles calculations, we have studied the electronic structure of 1144-type iron-based superconductor EuRbFe4As4. We find the crystal field splitting of EuRbFe4As4 is unique, such that the $$d_{z^2}$$

d

z

2

orbitals are closer to the Fermi level $$\epsilon _{\mathrm F}$$

ϵ

F

than the dxy orbitals. The Ruderman−Kittel−Kasuya−Yosida (RKKY) interaction strength is approximately 0.12 meV in pristine EuRbFe4As4. Upon Ni-doping on the Fe site, the RKKY interaction strength is barely changed upon Ni-doping due to the highly anisotropic Fermi surfaces and multiband effect, despite the drastically reduced dzx(y) density of state at $$\epsilon _{\mathrm F}$$

ϵ

F

. Finally, in both pristine and doped compounds, the RKKY interaction is primarily mediated through bands due to Fe-$$d_{z^2}$$

d

z

2

orbitals. Our calculations suggest the RKKY interaction mediated by $$d_{z^2}$$

d

z

2

orbital is probably responsible for the magnetism in EuRbFe4As4 and doesn’t change upon Ni-doping.
Sensitive and portable electrochemical immunoassay for lipoprotein-associated phospholipase A2 using BSA-doped CaCO3 nanospheres to regulate pH readout
Authors: Zhuang Wei , Li Yining , Weng Xiaoyuan , Guo Haixin , Zhang Yongquan , Yang Yating , Fan Chunmei
Published: February 2019

A simple and sensitive electrochemical immunoassay method was developed for the quantitative monitoring of lipoprotein-associated phospholipase A2 (Lp-PLA2) on a low-cost microtiter plate by using a portable handheld pH meter.
Band-selective dynamics in charge-transfer excited iron carbene complexes
Authors: Chábera Pavel , Fredin Lisa A. , Kjær Kasper S. , Rosemann Nils W. , Lindh Linnea , Prakash Om , Liu Yizhu , Wärnmark Kenneth , Uhlig Jens , Sundström Villy , Yartsev Arkady , Persson Petter
Published: February 2019

A combination of ultrafast spectroscopy and DFT/TD-DFT calculations of a recently synthesised iron carbene complex elucidates the ultrafast excited state evolution processes in these systems.