bluuebunny/crossref_metadata_2025 huggingface dataset:
Archival Predecessors and Indigenous Modernisms: Archives in Contemporary Curatorial Practice on the Northwest Coast
Authors: Kisin Eugenia
Published: February 2018

Les projets d’expositions archivistiques — et leur documentation — sont des lieux de production de connaissances en histoire de l’art, ainsi que des interventions politiques, qui placent les documents dans un autre contexte afin d’interroger les canons et les façons de voir des colonialistes-colons. À partir de ces relations discursives, visuelles et archivistiques, cet article examine deux rétrospectives solos des oeuvres sculptées et peintes des artistes modernistes kwakwaka’wakws, Doug Cranmer (‘Namgis) et Henry Speck (Tlawit’sis), présentées à Vancouver en 2012. En considérant comment les conservateurs ont fait appel aux archives familiales intimes et à des documents du domaine public, il traite de l’utilité des archives du modernisme pour activer des liens affectifs, ancestraux et familiaux au-delà des modes de compréhension canoniques et historiques des mouvements esthétiques et des contextes de production.
From Great-Grandmothers to Great-Granddaughters: “Moving Life” in Baby Carriers and Birchbark Baskets
Authors: Nahwegahbow Alexandra Kahsenni:io
Published: February 2018

Les porte-bébés et les paniers d’écorce autochtones sont, en tant que réceptacles, conçus pour porter et tenir. Outre cette fonction, ils sont aussi détenteurs d’histoires, de mémoire, et de liens familiaux. Créés individuellement et ornementés avec soin, ces objets constituent une sorte de portrait des femmes qui les ont produits, ainsi que des générations qui ont hérité des pratiques et des motifs servant à les fabriquer. En élargissant la définition de la notion de portrait de famille, cet article considère deux objets provenant de Bear Island, en Ontario. Le premier est un porte-bébé ayant appartenu à Madeline Katt Theriault, et le deuxième est un panier d’écorce vraisemblablement créé par son arrière-grand-mère Angele Katt. Par leur parenté, ces réceptacles englobent une histoire multigénérationnelle qui s’étend de l’arrière-grand-mère à son arrière-petite-fille.
Indigenous Sovereignty and Settler Amnesia: Robert Houle’s Premises for Self Rule
Authors: Ernst Stacy A.
Published: February 2018

Le modernisme en art est souvent considéré comme un développement spécifiquement occidental. Robert Houle, l’artiste, écrivain et commissaire d’exposition d’origine Saulteaux, a cependant toujours soutenu que sa propre pratique est moderniste et qu’elle suit une filiation esthétique autochtone. Cet article s’intéresse particulièrement à une oeuvre produite par Houle en 1994, Premises for Self Rule, dans laquelle l’artiste a juxtaposé des textes de législation coloniale à des panneaux peints en monochrome et des cartes postales trouvées en archives. Il propose qu’à travers cette stratégie de rapprochement, l’artiste fusionne la tradition de la peinture de parflèche à l’esthétique moderniste, remettant ainsi en lumière la négociation interculturelle, l’amnésie coloniale, ainsi que les écarts qui séparent les épistémologies et traditions artistiques des peuples autochtones et allochtones.
Efficience intellectuelle des enfants porteurs du Syndrome de Shwachman-Diamond : revue de littérature et prospectives de recherche
Authors: Canton Marie , Pastore Oriane , Trognon Alain , Bocéréan Christine , Fouyssac Fanny , Raffo Emmanuel , Donadieu Jean , Batt Martine
Published: February 2018

La revue de littérature et l’analyse clinique des profils intellectuels de sept enfants et adolescents porteurs d’un Syndrome de Shwachman-Diamond (SDS) au Wechsler Intelligence Scale for Children - IV (WISC-IV) mettent en évidence un affaiblissement intellectuel. Au-delà de la déficience intellectuelle, l’hypothèse d’un affaiblissement intellectuel lié à la présence de difficultés de raisonnement et d’un dysfonctionnement exécutif chez les enfants SDS ne présentant pas une déficience intellectuelle est soulevée. Ces éléments offrent un cadre d'interprétation intéressant et novateur à l'affaiblissement intellectuel objectivé mais aussi aux troubles comportementaux, sociaux et scolaires décrits dans cette population. Une évaluation spécifique et exhaustive du fonctionnement exécutif de ces enfants est recommandée, s’inscrivant dans une approche intégrative analysant les liens entre efficience intellectuelle, fonctionnements cognitif, émotionnel, comportemental, et performances scolaires.
Aggressive Surgical Management of Gallbladder Cancer: Long-Term Results From a Retrospective Study of 315 Chinese Patients
Authors: Nengwen Ke , Yong Zeng
Published: February 2018

Objective

To investigate the best surgical treatment for the gallbladder cancer patient.

Summary of Background Data

Until now, aggressive surgery for advanced gallbladder cancer has been controversial. In this study, we analyzed gallbladder cancer patients' data retrospectively to find out which is the best surgical treatment for the patient.

Methods

From 2009 to 2013, 315 cases of gallbladder carcinoma were identified. Data were analyzed retrospectively. The review included analysis of survival rate, postoperative complications, operative mortality rate, and correlation between local extent of the primary tumor and frequency of nodal metastases.

Results

Postoperative complications occurred in 15 patients (6.2%). A total of 3% of patients who underwent a radical surgery procedure had complications, but in the extended radical surgery group, it was 9.8%. Operative mortality rate was 4.94%. No lymph node metastases were found in patients with T1 tumors. Nodal involvement in patients with T3 (55.22%) and T4 (82.50%) tumors was significantly higher than that in patients with T2 tumors (44.12%). In patients with stages I and II cancers, the radical resection group had a better survival rate than the simple cholecystectomy group. In patients with stage III cancer, the extended radical surgery group and radical surgery group showed better survival rates than others. In patients with stage IV cancer, the extended radical surgery group showed a 4% survival rate at 2 years, but others group had a 0% survival rate.

Conclusions

Simple cholecystectomy may decrease the long survival rates in patients with stages I and II cancer. In more advanced stages, extended radical resection should be performed if R0 resections can be achieved.
The Dependence of Water Permeability in Quartz Sand on Gas Hydrate Saturation in the Pore Space
Authors: Kossel E. , Deusner C. , Bigalke N. , Haeckel M.
Published: February 2018

Transport of fluids in gas hydrate bearing sediments is largely defined by the reduction of the permeability due to gas hydrate crystals in the pore space. Although the exact knowledge of the permeability behavior as a function of gas hydrate saturation is of crucial importance, state‐of‐the‐art simulation codes for gas production scenarios use theoretically derived permeability equations that are hardly backed by experimental data. The reason for the insufficient validation of the model equations is the difficulty to create gas hydrate bearing sediments that have undergone formation mechanisms equivalent to the natural process and that have well‐defined gas hydrate saturations. We formed methane hydrates in quartz sand from a methane‐saturated aqueous solution and used magnetic resonance imaging to obtain time‐resolved, three‐dimensional maps of the gas hydrate saturation distribution. These maps were fed into 3‐D finite element method simulations of the water flow. In our simulations, we tested the five most well‐known permeability equations. All of the suitable permeability equations include the term (1‐SH)n, where SH is the gas hydrate saturation and n is a parameter that needs to be constrained. The most basic equation describing the permeability behavior of water flow through gas hydrate bearing sand is k = k0 (1‐SH)n. In our experiments, n was determined to be 11.4 (±0.3). Results from this study can be directly applied to bulk flow analysis under the assumption of homogeneous gas hydrate saturation and can be further used to derive effective permeability models for heterogeneous gas hydrate distributions at different scales.
Comprehensive Assessment of Global Surface Net Radiation Products and Uncertainty Analysis
Authors: Jia Aolin , Liang Shunlin , Jiang Bo , Zhang Xiaotong , Wang Guoxin
Published: February 2018

Earth surface net radiation (Rn) characterizes the surface radiation budget and plays a critical role in ecological, biogeochemical, and hydrological processes. The Rn products from remote sensing and reanalysis have not been validated comprehensively. In this study, four Rn products (Clouds and the Earth's Radiant Energy System [CERES], ERA‐Interim, Modern‐Era Retrospective analysis for Research and Applications version 2, and Japanese 55‐year Reanalysis) were validated using global ground measurements on monthly (255 sites) and annual (172 sites) timescales. These products have similar accuracies, with average root‐mean‐square error (RMSE) ranges of 5.35 W m−2 (monthly) and 2.30 W m−2 (annually). However, varying accuracies and systemic biases exist across different climatic zones. The annual land Rn intercomparison illustrates that large uncertainty exists over polar regions and deserts. A significantly negative annual anomaly in the CERES product for the 2001–2008 period is identified when examining annual Rn anomalies over the global land surface. Detailed uncertainty analysis indicates that the global CERES Rn anomaly is mainly due to different versions of input data such as aerosol optical thickness and atmospheric profiles (in 2006 and 2008) and cloud properties (in 2002). This work demonstrates that temporal analysis provides powerful quality control for global time series satellite products when the validation using ground measurements fails to capture potential issues.
Chemistry of Volatile Organic Compounds in the Los Angeles Basin: Formation of Oxygenated Compounds and Determination of Emission Ratios
Authors: de Gouw J. A. , Gilman J. B. , Kim S.‐W. , Alvarez S. L. , Dusanter S. , Graus M. , Griffith S. M. , Isaacman‐VanWertz G. , Kuster W. C. , Lefer B. L. , Lerner B. M. , McDonald B. C. , Rappenglück B. , Roberts J. M. , Stevens P. S. , Stutz J. , Thalman R. , Veres P. R. , Volkamer R. , Warneke C. , Washenfelder R. A. , Young C. J.
Published: February 2018

We analyze an expanded data set of oxygenated volatile organic compounds (OVOCs) in air measured by several instruments at a surface site in Pasadena near Los Angeles during the National Oceanic and Atmospheric Administration California Nexus study in 2010. The contributions of emissions, chemical formation, and removal are quantified for each OVOC using CO as a tracer of emissions and the OH exposure of the sampled air masses calculated from hydrocarbon ratios. The method for separating emissions from chemical formation is evaluated using output for Pasadena from the Weather Research and Forecasting‐Chemistry model. The model is analyzed by the same method as the measurement data, and the emission ratios versus CO calculated from the model output agree for ketones with the inventory used in the model but overestimate aldehydes by ~70%. In contrast with the measurements, nighttime formation of OVOCs is significant in the model and is attributed to overestimated precursor emissions and overestimated rate coefficients for the reactions of the precursors with ozone and NO3. Most measured aldehydes correlated strongly with CO at night, suggesting a contribution from motor vehicle emissions. However, the emission ratios of most aldehydes versus CO are higher than those reported in motor vehicle emissions and the aldehyde sources remain unclear. Formation of several OVOCs is investigated in terms of the removal of specific precursors. Direct emissions of alcohols and aldehydes contribute significantly to OH reactivity throughout the day, and these emissions should be accurately represented in models describing ozone formation.
High Spectral Resolution Spectroscopy of Sprites: A Natural Probe of the Mesosphere
Authors: Gordillo‐Vázquez F. J. , Passas M. , Luque A. , Sánchez J. , van der Velde O. A. , Montanyá J.
Published: February 2018

We present the first high spectral resolution (0.24 nm) spectra of sprites. These spectra were recorded in Europe in the summers and falls of 2015 and 2016 and during January 2017. The use of high spectral resolution has allowed us to resolve for the first time the internal (vibrorotational) structure of the sprite molecular N2 first positive system and to quantify the local gas (rotational) temperature of the mesosphere under the influence of sprites revealing that there is no measurable heating of the atmosphere associated to sprites at the altitudes explored. The temperatures of the explored region of the mesosphere range between 149 K ± 10 K and 226 K ± 20 K. The recorded spectroscopic data also provide valuable quantitative information on the concentrations of some of the vibrational levels of molecular nitrogen involved in transient red‐near‐infrared optical emissions from sprites. The regions of the transient luminous events recorded with our spectrograph (equipped with a horizontally oriented slit) correspond to altitudes in the 66 km to 74 km ± 5 km range.
Anisotropy of Observed and Simulated Turbulence in Marine Stratocumulus
Authors: Pedersen J. G. , Ma Y.‐F. , Grabowski W. W. , Malinowski S. P.
Published: February 2018

Anisotropy of turbulence near the top of the stratocumulus‐topped boundary layer (STBL) is studied using large‐eddy simulation (LES) and measurements from the POST and DYCOMS‐II field campaigns. Focusing on turbulence
m below the cloud top, we see remarkable similarity between daytime and nocturnal flight data covering different inversion strengths and free‐tropospheric conditions. With λ denoting wavelength and
cloud‐top height, we find that turbulence at
is weakly dominated by horizontal fluctuations, while turbulence at
becomes strongly dominated by horizontal fluctuations. Between are scales at which vertical fluctuations dominate. Typical‐resolution LES of the STBL (based on POST flight 13 and DYCOMS‐II flight 1) captures observed characteristics of below‐cloud‐top turbulence reasonably well. However, using a fixed vertical grid spacing of 5 m, decreasing the horizontal grid spacing and increasing the subgrid‐scale mixing length leads to increased dominance of vertical fluctuations, increased entrainment velocity, and decreased liquid water path. Our analysis supports the notion that entrainment parameterizations (e.g., in climate models) could potentially be improved by accounting more accurately for anisotropic deformation of turbulence in the cloud‐top region. While LES has the potential to facilitate improved understanding of anisotropic cloud‐top turbulence, sensitivity to grid spacing, grid‐box aspect ratio, and subgrid‐scale model needs to be addressed.
BAYSPLINE: A New Calibration for the Alkenone Paleothermometer
Authors: Tierney Jessica E. , Tingley Martin P.
Published: February 2018

The alkenone‐based U
proxy is a cornerstone of paleoclimatology, providing insight into the temperature history of the Earth's surface ocean. Although the relationship between U
and sea surface temperatures (SSTs) is robust and well supported by experimental data, there remain outstanding issues regarding the seasonality of production of alkenones and the response of U
at very warm and cold SSTs. Using a data set of over 1,300 core‐top U
measurements, we find compelling evidence of seasonal production in the North Atlantic, North Pacific, and Mediterranean Oceans. We also find significant attenuation of the U
response to SST at warm temperatures (>24°C), with the slope reduced by nearly 50% as U
approaches unity. To account for these observations in a calibration, we develop a new Bayesian B‐spline regression model, BAYSPLINE, for the U
paleothermometer. BAYSPLINE produces similar estimates as previous calibrations below ∼24°, but above this point it predicts larger SST changes, in accordance with the attenuation of the U
response. Example applications of BAYSPLINE demonstrate that its treatment of seasonality and slope attenuation improves paleoclimatic interpretations, with important consequences for the inference of SSTs in the tropical oceans. BAYSPLINE facilitates a probabilistic approach to paleoclimate, building upon growing efforts to develop more formalized statistical frameworks for paleoceanographic reconstruction.
Measuring Disease Damage and Its Severity in Childhood‐Onset Systemic Lupus Erythematosus
Authors: Holland Michael J. , Beresford Michael W. , Feldman Brian M. , Huggins Jennifer , Norambuena Ximena , Silva Clovis A. , Susic Gordana , Sztajnbok Flavio , Uziel Yosef , Appenzeller Simone , Ardoin Stacy P. , Avcin Tadej , Flores Francisco , Goilav Beatrice , Khubchandani Raju , Klein‐Gitelman Marissa , Levy Deborah , Ravelli Angelo , Wenderfer Scott E. , Ying Jun , Ruperto Nicolino , Brunner Hermine I. ,   the PRINTO and PRCSG Investigators
Published: February 2018

Objective

To describe the frequency and types of disease damage occurring with childhood‐onset systemic lupus erythematosus (SLE) as measured by the 41‐item Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI), and to assess the SDI's ability to reflect damage severity.

Methods

Information for the SDI was prospectively collected from 1,048 childhood‐onset SLE patients. For a subset of 559 patients, physician‐rated damage severity measured by visual analog scale (MD VAS damage) was also available. Frequency of SDI items and the association between SDI summary scores and MD VAS damage were estimated. Finally, an international consensus conference, using nominal group technique, considered the SDI's capture of childhood‐onset SLE–associated damage and its severity.

Results

After a mean disease duration of 3.8 years, 44.2% of patients (463 of 1,048) already had an SDI summary score >0 (maximum 14). The most common SDI items scored were proteinuria, scarring alopecia, and cognitive impairment. Although there was a moderately strong association between SDI summary scores and MD VAS damage (Spearman's r = 0.49, P < 0.0001) in patients with damage (SDI summary score >0), mixed‐effects analysis showed that only 4 SDI items, each occurring in <2% of patients overall, were significantly associated with MD VAS damage. There was consensus among childhood‐onset SLE experts that the SDI in its current form is inadequate for estimating the severity of childhood‐onset SLE–associated damage.

Conclusion

Disease damage as measured by the SDI is common in childhood‐onset SLE, even with relatively short disease durations. Given the shortcomings of the SDI, there is a need to develop new tools to estimate the impact of childhood‐onset SLE–associated damage.
Minimal Disease Activity Among Active Psoriatic Arthritis Patients Treated With Secukinumab: 2‐Year Results From a Multicenter, Randomized, Double‐Blind, Parallel‐Group, Placebo‐Controlled Phase III Study
Authors: Coates Laura C. , Mease Philip J. , Gossec Laure , Kirkham Bruce , Sherif Bintu , Gaillez Corine , Mpofu Shephard , Jugl Steffen M. , Karyekar Chetan , Gandhi Kunal K.
Published: February 2018

Objective

To evaluate minimal disease activity (MDA) among psoriatic arthritis (PsA) patients receiving secukinumab through 2 years in the FUTURE 2 study.

Methods

Patients with active PsA were randomized to receive subcutaneous secukinumab 300, 150, or 75 mg or placebo. MDA was assessed in the overall population (anti–tumor necrosis factor [anti‐TNF]–naive and inadequate responders [anti–TNF‐IR]) and in patients stratified by prior anti‐TNF exposure and by time since diagnosis at weeks 16, 24, 52, and 104. Function and patient‐reported outcomes (PROs), including health‐related quality of life (QoL) and work productivity, were assessed in MDA responders versus nonresponders.

Results

Overall, 28% of patients (27 of 98) and 23% (23 of 100) achieved MDA at week 16 with secukinumab 300 and 150 mg, respectively, versus 10% (9 of 94) with placebo. In the anti–TNF‐naive cohort, a higher proportion of patients achieved MDA at week 16 with secukinumab 300 and 150 mg (34% and 32%, respectively) versus placebo (13%). The corresponding value in the anti–TNF‐IR cohort was 15% and 8% with secukinumab 300 and 150 mg, respectively, versus with placebo (3%). At week 16, 27.1% of MDA responders (16 of 59) achieved a very low disease activity (VLDA) response, with the percentage being numerically greater with secukinumab 300 and 150 mg (30% [8 of 27] and 26% [6 of 23], respectively) versus placebo (22% [2 of 9]). The MDA and VLDA responses with secukinumab 300 and 150 mg were sustained through 2 years. MDA responders showed greater improvements in QoL outcomes compared to nonresponders through 2 years.

Conclusion

A greater proportion of patients achieved MDA with secukinumab versus placebo at week 16, with response rates sustained through 2 years. MDA was associated with improved PROs, including QoL, through 2 years.
Learning Analytics in Medical Education Assessment: The Past, the Present, and the Future
Authors: Chan Teresa , Sebok‐Syer Stefanie , Thoma Brent , Wise Alyssa , Sherbino Jonathan , Pusic Martin
Published: February 2018

With the implementation of competency‐based medical education (CBME) in emergency medicine, residency programs will amass substantial amounts of qualitative and quantitative data about trainees’ performances. This increased volume of data will challenge traditional processes for assessing trainees and remediating training deficiencies. At the intersection of trainee performance data and statistical modeling lies the field of medical learning analytics. At a local training program level, learning analytics has the potential to assist program directors and competency committees with interpreting assessment data to inform decision making. On a broader level, learning analytics can be used to explore system questions and identify problems that may impact our educational programs. Scholars outside of health professions education have been exploring the use of learning analytics for years and their theories and applications have the potential to inform our implementation of CBME. The purpose of this review is to characterize the methodologies of learning analytics and explore their potential to guide new forms of assessment within medical education.
N‐methyl‐D‐aspartate receptor antibody production from germinal center reactions: Therapeutic implications
Authors: Makuch Mateusz , Wilson Robert , Al‐Diwani Adam , Varley James , Kienzler Anne‐Kathrin , Taylor Jennifer , Berretta Antonio , Fowler Darren , Lennox Belinda , Leite M. Isabel , Waters Patrick , Irani Sarosh R
Published: February 2018

Introduction

N‐methyl‐D‐aspartate receptor (NMDAR) antibody encephalitis is mediated by immunoglobulin G (IgG) autoantibodies directed against the NR1 subunit of the NMDAR. Around 20% of patients have an underlying ovarian teratoma, and the condition responds to early immunotherapies and ovarian teratoma removal. However, despite clear therapeutic relevance, mechanisms of NR1‐IgG production and the contribution of germinal center B cells to NR1‐IgG levels are unknown.

Methods

Clinical data and longitudinal paired serum NR1‐reactive IgM and IgG levels from 10 patients with NMDAR‐antibody encephalitis were determined. Peripheral blood mononuclear cells from these 10 patients, and two available ovarian teratomas, were stimulated with combinations of immune factors and tested for secretion of total IgG and NR1‐specific antibodies.

Results

In addition to disease‐defining NR1‐IgG, serum NR1‐IgM was found in 6 of 10 patients. NR1‐IgM levels were typically highest around disease onset and detected for several months into the disease course. Moreover, circulating patient B cells were differentiated into CD19+CD27++CD38++ antibody‐secreting cells in vitro and, from 90% of patients, secreted NR1‐IgM and NR1‐IgG. Secreted levels of NR1‐IgG correlated with serum NR1‐IgG (p < 0.0001), and this was observed across the varying disease durations, suggestive of an ongoing process. Furthermore, ovarian teratoma tissue contained infiltrating lymphocytes which produced NR1‐IgG in culture.

Interpretation

Serum NR1‐IgM and NR1‐IgG, alongside the consistent production of NR1‐IgG from circulating B cells and from ovarian teratomas suggest that ongoing germinal center reactions may account for the peripheral cell populations which secrete NR1‐IgG. Cells participating in germinal center reactions might be a therapeutic target for the treatment of NMDAR‐antibody encephalitis. Ann Neurol 2018;83:553–561
Discovery and Enumeration of Organic‐Chemical and Biomimetic Reaction Cycles within the Network of Chemistry
Authors: Bajczyk Michał D. , Dittwald Piotr , Wołos Agnieszka , Szymkuć Sara , Grzybowski Bartosz A.
Published: February 2018

Analysis of the chemical‐organic knowledge represented as a giant network reveals that it contains millions of reaction sequences closing into cycles. Without realizing it, independent chemists working at different times have jointly created examples of cyclic sequences that allow for the recovery of useful reagents and for the autoamplification of synthetically important molecules, those that mimic biological cycles, and those that can be operated one‐pot.
Highly flame‐retardant polyurethane foam based on reactive phosphorus polyol and limonene‐based polyol
Authors: Bhoyate Sanket , Ionescu M. , Kahol P. K. , Chen J. , Mishra S. R. , Gupta Ram K.
Published: February 2018

Polyurethane foams are in general flammable and their flammability can be controlled by adding flame‐retardant (FR) materials. Reactive FR have the advantage of making strong bond within the polyurethane chains to provide excellent FR over time without compromising physico‐mechanical properties. Here, phenyl phosphonic acid and propylene oxide‐based reactive FR polyol was synthesized and used along with limonene based polyol for preparation of FR polyurethanes. All the obtained foams showed higher closed cell content (above 96%). By the addition of FR–polyol, the compressive strength of the foams showed 160% increment which could be due to reactive nature of FR–polyol. Moreover, 1.5 wt % of phosphorus (P) content reduced the self‐extinguishing time of the foam from 81 (28% weight loss) to 11.2 s (weight loss of 9.8%). Cone test showed 68.6% reduction in peak heat release rate along with 23.4% reduction in thermal heat release. The change in char structure of carbon after burning was analyzed using Raman spectra which, suggests increment in the graphitic phase of the carbon over increased concentration of phosphorus. It can be concluded from this study that phosphorous based polyol could be blended with bio‐based polyols to prepare highly FR and superior physico‐mechanical rigid polyurethane foams. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46224.
Second‐generation bio‐based plastics are becoming a reality – Non‐renewable energy and greenhouse gas (GHG) balance of succinic acid‐based plastic end products made from lignocellulosic biomass
Authors: Patel Martin K. , Bechu Aude , Villegas Juan David , Bergez‐Lacoste Manon , Yeung Kenny , Murphy Richard , Woods Jeremy , Mwabonje Onesmus N. , Ni Yuanzhi , Patel Akshay D. , Gallagher Joe , Bryant David
Published: February 2018

Bio‐based and bio‐degradable plastics such as polybutylene succinate (PBS) have the potential to become sustainable alternatives to petrochemical‐based plastics. Polybutylene succinate can be produced from bio‐based succinic acid and 1,4‐butanediol using first‐generation (1G) or second‐generation (2G) sugars. A cradle‐to‐grave environmental assessment was performed for PBS products in Europe to investigate the non‐renewable energy use (NREU) and greenhouse gas (GHG) impacts. The products investigated are single‐use trays and agricultural film, with incineration, industrial composting and degradation on agricultural land as end‐of‐life scenarios. Both end products manufactured from fully bio‐based PBS and from partly bio‐based PBS (made from bio‐based succinic acid and fossil fuel‐based 1,4 butanediol) were analysed. We examine corn (1G) as well as corn stover, wheat straw, miscanthus and hardwood as 2G feedstocks. For the cradle‐to‐grave system, 1G fully bio‐based PBS plastic products were found to have environmental impacts comparable with their petrochemical incumbents, while 2G fully bio‐based PBS plastic products allow to reduce NREU and GHG by around one third under the condition of avoidance of concentration of sugars and energy integration of the pretreatment process with monomer production. Without energy integration and with concentration of sugars (i.e., separate production), the impacts of 2G fully bio‐based PBS products are approximately 15–20% lower than those of 1G fully bio‐based PBS products. The environmental analysis of PBS products supports the value proposition related to PBS products while also pointing out areas requiring further research and development. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd
Planung und Ausführung von Fugen und Fugenabdichtungssystemen für WU‐Konstruktionen
Authors: Hohmann Rainer
Published: February 2018

Wasserundurchlässige Bauwerke aus Beton, sogenannte „Weiße Wannen”, müssen im Regelfall das Eindringen oder das Austreten von Wasser verhindern oder beides. Hierzu müssen alle Arbeitsfugen, Dehnfugen, Sollrissquerschnitte und Durchdringungen planmäßig dauerhaft wasserdicht abgedichtet werden. Die Ausbildung der Fugen und deren Abdichtung erfordern die besondere Beachtung von Planern und Ausführenden. Dies setzt vertiefte Kenntnisse über Fugen, die unterschiedlichen Fugenabdichtungssysteme und deren fachgerechter Anwendung voraus. Der Beitrag bietet einen Überblick über die Fugenabdichtungssysteme und gibt Hinweise für die Auswahl, Planung und Bauausführung der unterschiedlichen Fugenabdichtungssysteme.
Injektion von Rissen und Hohlräumen in WU‐Beton
Authors: Graeve Holger
Published: February 2018

Wasserundurchlässigkeit macht Beton über seine Festigkeitseigenschaften, seine Formbarkeit und Wirtschaftlichkeit hinaus zu einem Baustoff mit besonderer Funktionalität. Sein Einsatz für Bauwerke ohne zusätzliche wasserseitige Abdichtungsmaßnahmen erfordert besondere Sorgfalt in Planung und Ausführung. Letztlich müssen auch die Grenzen der Leistungsfähigkeit beachtet werden.

Die Vermeidung oder Begrenzung zu erwartender Rissbildung durch konstruktive, betontechnologische und ausführungstechnische Maßnahmen wird von der Bauindustrie beherrscht. Dennoch bleiben Trennrisse unvermeidbar. Injektionstechnologien stellen den angestrebten Zustand der Wasserundurchlässigkeit wieder her.

In der Baupraxis sind partiell notwendige Injektionen herstellungsbedingter Bestandteil der Stahlbetonbauweise, insbesondere an wasserundurchlässigen Betonkonstruktionen. Die erfolgreiche Anwendung von Injektionssystemen erfordert die Kenntnis betontechnischer Grundlagen auf der einen Seite, Kenntnisse zum Wassertransport in Beton und zur Injektionstechnologie auf der anderen Seite.

Die Injizierbarkeit unvermeidbarer Risse wurde schon relativ früh untersucht [1]. Über den Wassertransport durch Beton wurden daraufhin zusätzliche Untersuchungsergebnisse vorgelegt [2]. Weitere Arbeiten widmeten sich der Selbstheilung von Trennrissen in Beton [3] und dem technischen Stand der Injektion von Rissen und Hohlräumen in Betonbauteilen [4]. Sie bieten die Grundlagen zur erfolgreichen Anwendung von wasserundurchlässigem Beton in Verbindung mit Injektionsmaßnahmen.
L‐Cysteine Production in Escherichia coli Based on Rational Metabolic Engineering and Modular Strategy
Authors: Liu Han , Fang Guochen , Wu Hui , Li Zhimin , Ye Qin
Published: February 2018

L‐cysteine is an amino acid with important physiological functions and has a wide range of applications in medicine, food, animal feed, and cosmetics industry. In this study, the L‐cysteine synthesis in Escherichia coliEscherichia coli is divided into four modules: the transport module, sulfur module, precursor module, and degradation module. The engineered strain LH03 (overexpression of the feedback‐insensitive cysE and the exporter ydeD in JM109) accumulated 45.8 mg L−1 of L‐cysteine in 48 hr with yield of 0.4% g/g glucose. Further modifications of strains and culture conditions which based on the rational metabolic engineering and modular strategy improved the L‐cysteine biosynthesis significantly. The engineered strain LH06 (with additional overexpression of serA, serC, and serB and double mutant of tnaA and sdaA in LH03) produced 620.9 mg L−1 of L‐cysteine with yield of 6.0% g/g glucose, which increased the production by 12 times and the yield by 14 times more than those of LH03 in the original condition. In fed‐batch fermentation performed in a 5‐L reactor, the concentration of L‐cysteine achieved 5.1 g L−1 in 32 hr. This work demonstrates that the combination of rational metabolic engineering and module strategy is a promising approach for increasing the L‐cysteine production in E. coli.
Conscious sedation for TAVR: A wave of the future?
Authors: Tan Christina , Dean Larry S.
Published: February 2018

Key Points

As indications for TAVR continue to grow, experienced centers strive to adopt further minimally invasive techniques and continue to improve outcomes.

Meta‐analysis of the available data demonstrate that conscious sedation is associated with decreased ICU and hospitalization time, and is not associated with decreased procedural efficacy or safety.

Randomized Controlled clinical Trial data will be needed to confirm observational findings suggesting decreased mortality with conscious sedation versus general anesthesia.
Cardiac enzyme elevation after coronary revascularization
Authors: Plitt Anna , Dangas George
Published: February 2018

Key Points

CK‐MB elevation post‐PCI correlates with procedural complications, diffuse atherosclerosis, and adverse long‐term prognosis.

Troponin elevation has an earlier pattern of rise than CK‐MB and can be used as a surrogate.

High sensitivity troponin can enable ruling out enzymatic elevation very early after PCI and facilitate discharge timing.
The promise of effective P2Y12 platelet receptor pretreatment: Not crushed yet
Authors: Chatterjee Arka , Hillegass William B.
Published: February 2018

Key Points

Pre‐treatment with intact oral clopidogrel and prasugrel tablets in a representative observational study is not associated with altered ischemic or bleeding outcomes in acute coronary syndrome (ACS) patients.

Limited by cost, cangrelor, a rapidly acting intravenous P2Y12 platelet receptor inhibitor, achieved meaningful reductions in major adverse cardiovascular events (MACE) and stent thrombosis (ST) compared to oral clopidogrel pretreatment.

Crushed prasugrel and ticagrelor (CP&T) administered orally achieve accepted thresholds of therapeutic platelet inhibition in one hour in approximately 2/3rds of patients compared to 1/3rd with intact oral tablets. A large, simple randomized trial should test whether CP&T pre‐treatment could capture some of the potential outcome benefit of rapid P2Y12 inhibition at no incremental risk and cost.
Increased mortality in octogenarians treated for lifestyle limiting claudication
Authors: Erben Young , Mena‐Hurtado Carlos I. , Miller Samuel M. , Jean Raymond A. , Sumpio Brandon J. , Velasquez Camilo A. , Mojibian Hamid , Aruny John , Dardik Alan , Sumpio Bauer E.
Published: February 2018

Objective

Treatment for lifestyle limiting claudication (LLC) that is due to infra‐inguinal peripheral artery disease relies on either bypass, angioplasty, and/or stenting. Given the enthusiasm and shift toward more endovascular therapy for treatment of LLC, we sought to analyze whether octogenarians benefit from infra‐inguinal interventions in the same manner as their younger counterparts.

Methods

We identified all patients admitted for elective treatment of LLC from the Nationwide Inpatient Sample from 2003 to 2012, who received open surgical or endovascular intervention for infra‐inguinal peripheral arterial disease. These patients were divided into two groups including those between the ages 60–80 years (younger cohort) and those older than 80 years (octogenarians). Primary end‐points included morbidity and mortality and the secondary end‐points were length of hospital stay (LOS) and disposition after dismissal.

Results

Among 59,323 discharges identified in the dataset, 34,658 (58%) were males. There were 50,323 (85%) patients in the younger cohort and 9,000 (15%) octogenarians. The mean age was 69.9 ± 5.7 years and 84.2 ± 3.0 years for the younger cohort and octogenarians, respectively. The mean Charlson comorbidity index (CCI) was higher in our younger cohort (2.1 ± 1.1, P < 0.001). Octogenarians mainly treated with open surgery prior to 2004 are now treated endovascularly and this trend has remained stable. The younger cohort's treatment modality has fluctuated through the study period and most recently is treated mainly with open surgery. The rate of acute kidney injury, exacerbation of congestive heart failure and mortality was higher in octogenarians (P < 0.001). The rate of infectious wound complications was higher in the younger cohort (P < 0.05). Octogenarians have longer LOS and are dismissed in higher percentage to a skilled nursing facility (P < 0.001). On binary logistic regression analysis, age over 80 years, female sex, higher CCI and having an open as opposed to an endovascular procedure are independent predictors of in‐hospital mortality.

Conclusions

Although endovascular techniques seem to dominate the care for octogenarians with LLC, the overall morbidity and mortality rates are significantly higher in this patient population. Other options such as medical management and/or supervised exercise therapy should be explored in this patient group.
Transcatheter pledget‐assisted suture tricuspid annuloplasty (PASTA) to create a double‐orifice valve
Authors: Khan Jaffar M. , Rogers Toby , Schenke William H. , Greenbaum Adam B. , Babaliaros Vasilis C. , Paone Gaetano , Ramasawmy Rajiv , Chen Marcus Y. , Herzka Daniel A. , Lederman Robert J.
Published: February 2018

Objectives

Pledget‐assisted suture tricuspid valve annuloplasty (PASTA) is a novel technique using marketed equipment to deliver percutaneous trans‐annular sutures to create a double‐orifice tricuspid valve.

Background

Tricuspid regurgitation is a malignant disease with high surgical mortality and no commercially available transcatheter solution in the US.

Methods

Two iterations of PASTA were tested using trans‐apical or trans‐jugular access in swine. Catheters directed paired coronary guidewires to septal and lateral targets on the tricuspid annulus under fluoroscopic and echocardiographic guidance. Guidewires were electrified to traverse the annular targets and exchanged for pledgeted sutures. The sutures were drawn together and knotted, apposing septal and lateral targets, creating a double orifice tricuspid valve.

Results

Twenty‐two pigs underwent PASTA. Annular and chamber dimensions were reduced (annular area, 10.1 ± 0.8 cm2 to 3.8 ± 1.5 cm2 (naïve) and 13.1 ± 1.5 cm2 to 6.2 ± 1.0 cm2 (diseased); septal‐lateral diameter, 3.9 ± 0.3 mm to 1.4 ± 0.6 mm (naïve) and 4.4 ± 0.4 mm to 1.7 ± 1.0 mm (diseased); and right ventricular end‐diastolic volume, 94 ± 13 ml to 85 ± 14 ml (naïve) and 157 ± 25 ml to 143 ± 20 ml (diseased)). MRI derived tricuspid regurgitation fraction fell from 32 ± 12% to 4 ± 5%. Results were sustained at 30 days. Pledget pull‐through force was five‐fold higher (40.6 ± 11.7N vs 8.0 ± 2.6N, P < .01) using this strategy compared to single puncture techniques used to anchor current investigational devices. Serious complications were related to apical access.

Conclusions

PASTA reduces annular dimensions and tricuspid regurgitation in pigs. It may be cautiously applied to selected patients with severe tricuspid regurgitation and no options. This is the first transcatheter procedure, to our knowledge, to deliver standard pledgeted sutures to repair cardiac pathology.
Understanding the Cyclic (In)stability and the Effects of Presence of a Stable Conducting Network on the Electrochemical Performances of Na2Ti3O7
Authors: Bhardwaj Hem Shruti , Ramireddy Thrinathreddy , Pradeep Anagha , Jangid Manoj K. , Srihari Velaga , Poswal Himanshu K. , Mukhopadhyay Amartya
Published: February 2018

Despite being a promising anode material for the Na‐ion battery system, Na‐titanate (viz., Na2Ti3O7) lacks in terms of cyclic stability; the cause(s) for which are under debate. Against this backdrop, through electrochemical measurements and in situ synchrotron X‐ray diffraction studies, the present work develops insights into the aspects concerning electrochemical reversibility of the fully sodiated phase (i.e., Na4Ti3O7), possible occurrence of irreversible reactions in Na‐ion cells, influences of the same towards cyclic instability, and a strategy towards alleviating this problem. The in situ studies rule out (in)stability/(ir)reversibility of Na4Ti3O7 as being a major cause for the capacity fade; rather they indicate the formation of ‘impurity’ phase(s) due to reaction with the electrolyte. Incorporation of multi‐walled carbon nanotubes (MWCNTs; uniformly ‘wrapping’ the rod‐shaped Na2Ti3O7 particles) significantly improved the cyclic stability (ca. 78 % reversible capacity retention after 50 cycles, as compared to ca. 6 % without MWCNTs) and rate capability (with nearly flat potential plateaus at 5C). The same suppressed the increase in charge‐transfer resistance upon cycling by an order of magnitude and also changed the sodiation reaction from being primarily surface to diffusion controlled. Correlation of the results/analysis indicate that, in the absence of a stable conducting network, loss in electrical connectivity owing to the formation of insulating/passivating (surface) phase(s) is the major cause for capacity fade of Na2Ti3O7.
AN ABSOLUTE PLATE MOTION MODEL BASED ON HOTSPOT REFERENCE FRAME
Authors: Qiong ZHANG , Shi‐Min WANG , Yong‐Hong ZHAO
Published: February 2018

Based on the new generation model of relative plate motions, the MOVEL model, an absolute plate motion model is built by least squares inversion of the observed hotspot trend data. A systematic test for the consistency between the MOVEL model and all the available hotspot data adopted by previous studies of absolute plate motion models shows there are outliers in the data set. Accordingly, two new methods to reject outliers, such as, step‐wise rejection and global search rejection, are proposed. Combined with the chi‐square test for the total residual and the normal test for the residual frequency distribution, the best model is selected step by step. A T87 model is eventually obtained. This model provides reasonable fitting to 87 globally distributed hotspot trends, but the predicted plate velocities are systematically lower than the observed rates of volcanic migration along hotspot tracks with the deviation up to 4 cm·a−1. Such a deviation may be explained as a consequence of systematic errors possibly associated with the observed hotspot rate data, or due to relative motions between hotspots caused by mantle return flow. For either case, however, this study's results demonstrate that the hotspot trend data are capable of defining a global hotspot reference frame independently and effectively, which could be conveniently applied to studies on absolute plate motion, mantle convection and true polar wander.
NEAR‐FIELD SEISMIC LOCALIZATION USING DELTA T MAPPING
Authors: Peng‐Cheng SHI , Yuan WANG , Qing‐Yu YOU
Published: February 2018

Near‐field seismic localization has important significance and wide applications in the real world, for instance, locating explosions or tracking traffic movements. The traditional methods designed for far‐field scenarios are limited here due to the unknown velocity structures and high accuracy demands. This paper, for the first time, applied the Delta T Mapping (DTM) technique from acoustic emission detection in near‐field seismic localization. DTM first needs to construct a mapping of the difference of first arrivals on which the following locating is based. There are two approaches for establishing such model: (1) grid search method: using linear scattered point interpolation to obtain new DTM of higher resolution; (2) statistical locating method: using Gaussian Process Regression to build the mapping from Delta T to positions. The experiment was conducted in an area of 140 m×90 m in the suburb of Beijing. The locating error was 0.5∼5.1 m. The results showed that DTM is reliable, highly accurate and suitable for real‐time use for near‐field seismic localization. The cost of learning DTM and analyzing data could be further decreased while obtaining highly accurate DTM by switching the sources and receivers. Furthermore, combining source‐scan algorithm has certain potential to locate multi‐sources.
HIGH RESOLUTION VELOCITY STRUCTURE OF THE NORTH CHINA CRATON BASEMENT BY BLASTING SEISMIC WAVE—RESULTS FROM DAFENG–BAOTOU REFRACTION PROFILE
Authors: Jin‐Ren ZHAO , Bao‐Jin LIU , Yong‐Hong DUAN , Su‐Zhen PAN , Zhen‐Yu FAN , Ce‐Jun MA , Xiao‐Guo DENG , Yan HAI , Shuai‐Jun WANG , Ming‐Xin QU
Published: February 2018

Due to the high density of observation points and shots, we obtained the 21‐shot seismic data with high signal‐to‐noise ratio along the 1334 km long Dafeng‐Baotou profile. On the basis of the analysis of the Pg wave phase characteristics, we processed the data by the inversion method and constructed the fine structure of the basement, revealing the discrepancy of basement structure in different tectonic blocks. The basement depth of Northern Jiangsu basin is 4.5∼9.0 km and that of Jiangsu‐Shandong uplift is 1.5∼2.0 km. Strong fluctuations of the burial depth and velocity structure may be considered as the seismologic manifestation of the collision and extrusion between North China and the Yangtze plate. The basement of Western Shandong uplift area shows the feature of shallow burial depth, high speed and stable structure, while the Pg wave characteristics in the North China basin are lagged travel time, low apparent velocity, basement depth from 7.0 km to 10.0 km, and the local fluctuations in the velocity structure and basement interface. Lots of phenomena above reveal that this area is a large‐scale basement depression zone with thick Cenozoic sediment. Moreover, in different tectonic units of the basin, the tectonic pattern of local basement patch and coexistence of depression and uplift shows obvious tectonic characteristics, such as remarkable Cenozoic sedimentary activities, significant velocity and thickness changes and the unstable structure. Taihang mountain piedmont fault and Liaolan fault are significant seismologic features. On both sides of these two faults, the velocity structure shows intensive lateral heterogeneity, and the basement interfaces collapse as cliff. This study reveals that the Taihang mountain piedmont fault is an important tectonic zone in North China. Its complexity is not only reflected in different landforms and strata on its two sides, but also reflected in the significant differences among the basement depth, velocity structure, the crust and even the mantle lithospheric structures. To the east of Taihang mountain, the important symbol is large scale crustal and lithospheric thinning, which result in the obvious differences and strong lateral heterogeneity of the basement structure, the crust and even the lithosphere structures between the western and eastern North China Craton destruction