bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical and computational comparison of continuous‐time process scheduling models for adjustable robust optimization
Authors: Lappas Nikolaos H. , Gounaris Chrysanthos E.
Published: February 2018

Coping with uncertainty in system parameters is a prominent hurdle when scheduling multi‐purpose batch plants. In this context, our previously introduced multi‐stage adjustable robust optimization (ARO) framework has been shown to obtain more profitable solutions, while maintaining the same level of immunity against risk, as compared to traditional robust optimization approaches. This paper investigates the amenability of existing deterministic continuous‐time scheduling models to serve as the basis of this ARO framework. A comprehensive computational study is conducted that compares the numerical tractability of various models across a suite of literature benchmark instances and a wide range of uncertainty sets. This study also provides, for the first time in the open literature, robust optimal solutions to process scheduling instances that involve uncertainty in production yields. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3055–3070, 2018
Migration Factors in West African Immigrant Parents’ Perceptions of Their Children's Neighborhood Safety
Authors: Rasmussen Andrew , Cissé Aïcha , Han Ying , Roubeni Sonia
Published: February 2018

Immigrants make up large proportions of many low‐income neighborhoods, but have been largely ignored in the neighborhood safety literature. We examined perceived safety's association with migration using a six‐item, child‐specific measure of parents’ perceptions of school‐aged (5–12 years of age) children's safety in a sample of 93 West African immigrant parents in New York City. Aims of the study were (a) to identify pre‐migration correlates (e.g., trauma in home countries), (b) to identify migration‐related correlates (e.g., immigration status, time spent separated from children during migration), and (c) to identify pre‐migration and migration correlates that accounted for variance after controlling for non‐migration‐related correlates (e.g., neighborhood crime, parents’ psychological distress). In a linear regression model, children's safety was associated with borough of residence, greater English ability, less emotional distress, less parenting difficulty, and a history of child separation. Parents’ and children's gender, parents’ immigration status, and the number of contacts in the U.S. pre‐migration and pre‐migration trauma were not associated with children's safety. That child separation was positively associated with safety perceptions suggests that the processes that facilitate parent–child separation might be reconceptualized as strengths for transnational families. Integrating migration‐related factors into the discussion of neighborhood safety for immigrant populations allows for more nuanced views of immigrant families’ well‐being in host countries.
Body size and body composition effects on heat loss from the hands during severe cold exposure
Authors: Payne Stephanie , Macintosh Alison , Stock Jay
Published: February 2018

Objectives

This study investigated the influence of body size and composition on maintaining hand temperature during severe cold exposure. The hand's high surface area‐to‐volume ratio predisposes the hand to heat loss, increasing the risk of cold injury and even hypothermia, which are major selective pressures in cold environments. While vasoregulation may reduce heat loss from the hand, the effect of body form, tissue thermogenesis, and body insulation on heat loss is unknown.

Materials and Methods

Thermal imaging was used to determine heat loss during a 3‐min ice‐water hand immersion test carried out on 114 volunteers (female = 63, male = 51). Established anthropometric measures were used to quantify body size, and bioelectrical impedance analysis determined skeletal muscle and fat mass.

Results

Skeletal muscle mass relative to body mass was a highly significant predictor of heat loss, while body mass, fat mass, and stature were not. Body composition and body size had little to no significant influence during rewarming after immersion.

Discussion

The thermogenic properties of muscle mass support maintenance of hand temperature during severe cold exposure. The findings here suggest that muscular individuals are less susceptible to heat loss and cold injury, and may be better at manual tasks in cold conditions than nonmuscular individuals.
Reifung von Proben beeinflusst die Effizienz der Kernpolarisation
Authors: Weber Emmanuelle M. M. , Sicoli Giuseppe , Vezin Hervé , Frébourg Ghislaine , Abergel Daniel , Bodenhausen Geoffrey , Kurzbach Dennis
Published: February 2018

Mischungen von Wasser und Glycerin sind populäre Matrizen für die Tieftemperaturspektroskopie verglaster Proben. Allerdings besitzen solche Mischungen konterintuitive Eigenschaften, wie spontane Nanophasenseparation in Lösungen, die makroskopisch homogen scheinen. Wir zeigen hier, dass solche Phänomene die Effizienz der dynamischen Kernpolarisation stark beeinflussen können, durch Fluktuation der lokalen Konzentration der Polarisationsmittel (Radikale) um bis zu 20 %. Spontane Nanophasenseparationen, die auf Zeitskalen von 30–60 min stattfinden, resultieren in lokalen wasserreichen Einschlüssen mit erhöhter Radikalkonzentration. Solche Phänomene wurden für die drei häufigen Polarisationsmittel TEMPOL, AMUPol und Trityl beobachtet.
Metal–Organic Frameworks for High Charge–Discharge Rates in Lithium–Sulfur Batteries
Authors: Jiang Haoqing , Liu Xiao‐Chen , Wu Yushan , Shu Yufei , Gong Xuan , Ke Fu‐Sheng , Deng Hexiang
Published: February 2018

We report a new method to promote the conductivities of metal–organic frameworks (MOFs) by 5 to 7 magnitudes, thus their potential in electrochemical applications can be fully revealed. This method combines the polarity and porosity advantages of MOFs with the conductive feature of conductive polymers, in this case, polypyrrole (ppy), to construct ppy‐MOF compartments for the confinement of sulfur in Li–S batteries. The performances of these ppy‐S‐in‐MOF electrodes exceed those of their MOF and ppy counterparts, especially at high charge–discharge rates. For the first time, the critical role of ion diffusion to the high rate performance was elucidated by comparing ppy‐MOF compartments with different pore geometries. The ppy‐S‐in‐PCN‐224 electrode with cross‐linked pores and tunnels stood out, with a high capacity of 670 and 440 mAh g−1 at 10.0 C after 200 and 1000 cycles, respectively, representing a new benchmark for long‐cycle performance at high rate in Li–S batteries.
Coupling of Bifunctional CoMn‐Layered Double Hydroxide@Graphitic C3N4 Nanohybrids towards Efficient Photoelectrochemical Overall Water Splitting
Authors: Arif Muhammad , Yasin Ghulam , Shakeel Muhammad , Fang Xiaoyu , Gao Rui , Ji Shengfu , Yan Dongpeng
Published: February 2018

The development of durable, low‐cost, and efficient photo‐/electrolysis for the oxygen and hydrogen evolution reactions (OER and HER) is important to fulfill increasing energy requirements. Herein, highly efficient and active photo‐/electrochemical catalysts, that is, CoMn‐LDH@g‐C3N4 hybrids, have been synthesized successfully through a facile in situ co‐precipitation method at room temperature. The CoMn‐LDH@g‐C3N4 composite exhibits an obvious OER electrocatalytic performance with a current density of 40 mA cm−2 at an overpotential of 350 mV for water oxidation, which is 2.5 times higher than pure CoMn‐LDH nanosheets. For HER, CoMn‐LDH@g‐C3N4 (η50=−448 mV) requires a potential close to Pt/C (η50=−416 mV) to reach a current density of 50 mA cm2. Furthermore, under visible‐light irradiation, the photocurrent density of the CoMn‐LDH@g‐C3N4 composite is 0.227 mA cm−2, which is 2.1 and 3.8 time higher than pristine CoMn‐LDH (0.108 mA cm−2) and g‐C3N4 (0.061 mA cm−2), respectively. The CoMn‐LDH@g‐C3N4 composite delivers a current density of 10 mA cm−2 at 1.56 V and 100 mA cm−2 at 1.82 V for the overall water‐splitting reaction. Therefore, this work establishes the first example of pure CoMn‐LDH and CoMn‐LDH@g‐C3N4 hybrids as electrochemical and photoelectrochemical water‐splitting systems for both OER and HER, which may open a pathway to develop and explore other LDH and g‐C3N4 nanosheets as efficient catalysts for renewable energy applications.
Carbon and Carbon Hybrid Materials as Anodes for Sodium‐Ion Batteries
Authors: Zhong Xiongwu , Wu Ying , Zeng Sifan , Yu Yan
Published: February 2018

Sodium‐ion batteries (SIBs) have attracted much attention for application in large‐scale grid energy storage owing to the abundance and low cost of sodium sources. However, low energy density and poor cycling life hinder practical application of SIBs. Recently, substantial efforts have been made to develop electrode materials to push forward large‐scale practical applications. Carbon materials can be directly used as anode materials, and they show excellent sodium storage performance. Additionally, designing and constructing carbon hybrid materials is an effective strategy to obtain high‐performance anodes for SIBs. In this review, we summarize recent research progress on carbon and carbon hybrid materials as anodes for SIBs. Nanostructural design to enhance the sodium storage performance of anode materials is discussed, and we offer some insight into the potential directions of and future high‐performance anode materials for SIBs.
Special interests and subjective wellbeing in autistic adults
Authors: Grove Rachel , Hoekstra Rosa A , Wierda Marlies , Begeer Sander
Published: February 2018

Special interests form part of the core features of autism. However, to date there has been limited research focusing on the role of special interests in the lives of autistic adults. This study surveyed autistic adults on their special interest topics, intensity, and motivation. It also assessed the relationship between special interests and a range of quality of life measures including subjective wellbeing and domain specific life satisfaction. About two thirds of the sample reported having a special interest, with relatively more males reporting a special interest than females. Special interest topics included computers, autism, music, nature and gardening. Most autistic adults engaged in more than one special interest, highlighting that these interests may not be as narrow as previously described. There were no differences in subjective wellbeing between autistic adults with and without special interests. However, for autistic adults who did have special interests, motivation for engaging in special interests was associated with increased subjective wellbeing. This indicates that motivation may play an important role in our understanding of special interests in autism. Special interests had a positive impact on autistic adults and were associated with higher subjective wellbeing and satisfaction across specific life domains including social contact and leisure. However, a very high intensity of engagement with special interests was negatively related to wellbeing. Combined, these findings have important implications for the role of special interests in the lives of autistic adults. Autism Res 2018, 11: 766–775. © 2018 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

Autistic adults reported having special interests in a range of topics, including computers, music, autism, nature and gardening. Special interests were associated with a number of positive outcomes for autistic adults. They were also related to subjective wellbeing and satisfaction across specific life domains including social contact and leisure. Very high intensity of engagement with special interests was related to lower levels of wellbeing. This highlights the important role that special interests play in the lives of autistic adults.
3‐D‐Druck mit Beton: Sachstand, Entwicklungstendenzen, Herausforderungen
Authors: Mechtcherine Viktor , Nerella Venkatesh Naidu
Published: February 2018

Die Entwicklung digitaler Betondruckverfahren zur Herstellung von Betonbauteilen direkt auf der Baustelle oder im Fertigteilwerk ist ein entscheidender Schritt auf dem Weg zur Einführung des Industrie‐4.0‐Konzepts in das Bauwesen, nämlich von der bereits existierenden digitalen Bauplanung (CAD, BIM) bis hin zur digitalen Fertigung. Das technologische und wirtschaftliche Potenzial des digitalen Betonbaus wurde inzwischen von vielen am Bau Beteiligten und Forschern erkannt; der Umfang von Innovationsaktivitäten auf diesem Gebiet steigt von Monat zu Monat. Der Beitrag gibt einen Überblick über diese Entwicklungen und bewertet sie kritisch. Nach der Vorstellung alternativer Ansätze der digitalen Fertigung befassen sich die Autoren näher mit den auf der Extrusion basierenden Verfahren. Für den 3‐D‐Druck mit Beton sind diese Verfahren derzeit am häufigsten verwendet und weisen auch das größte Potenzial im Hinblick auf die Überführung der neuen Technologie in die Baupraxis auf. Dabei stehen jedoch zahlreiche Herausforderungen bezüglich Materialentwicklung und ‐prüfung, Bemessung, Maschinentechnik und vieles mehr an. Auf diese Herausforderungen wird im vorliegenden Aufsatz ebenfalls eingegangen und es werden mögliche Lösungsansätze skizziert.
Cerebral embolization, silent cerebral infarction and neurocognitive decline after thoracic endovascular aortic repair
Authors: Perera A. H. , Rudarakanchana N. , Monzon L. , Bicknell C. D. , Modarai B. , Kirmi O. , Athanasiou T. , Hamady M. , Gibbs R. G.
Published: February 2018

Background

Silent cerebral infarction is brain injury detected incidentally on imaging; it can be associated with cognitive decline and future stroke. This study investigated cerebral embolization, silent cerebral infarction and neurocognitive decline following thoracic endovascular aortic repair (TEVAR).

Methods

Patients undergoing elective or emergency TEVAR at Imperial College Healthcare NHS Trust and Guy's and St Thomas' NHS Foundation Trust between January 2012 and April 2015 were recruited. Aortic atheroma graded from 1 (normal) to 5 (mobile atheroma) was evaluated by preoperative CT. Patients underwent intraoperative transcranial Doppler imaging (TCD), preoperative and postoperative cerebral MRI, and neurocognitive assessment.

Results

Fifty-two patients underwent TEVAR. Higher rates of TCD-detected embolization were observed with greater aortic atheroma (median 207 for grade 4–5 versus 100 for grade 1–3; P = 0·042), more proximal landing zones (median 450 for zone 0–1 versus 72 for zone 3–4; P = 0·001), and during stent-graft deployment and contrast injection (P = 0·001). In univariable analysis, left subclavian artery bypass (β coefficient 0·423, s.e. 132·62, P = 0·005), proximal landing zone 0–1 (β coefficient 0·504, s.e. 170·57, P = 0·001) and arch hybrid procedure (β coefficient 0·514, s.e. 182·96, P < 0·001) were predictors of cerebral emboli. Cerebral infarction was detected in 25 of 31 patients (81 per cent) who underwent MRI: 21 (68 per cent) silent and four (13 per cent) clinical strokes. Neurocognitive decline was seen in six of seven domains assessed in 15 patients with silent cerebral infarction, with age a significant predictor of decline.

Conclusion

This study demonstrates a high rate of cerebral embolization and neurocognitive decline affecting patients following TEVAR. Brain injury after TEVAR is more common than previously recognized, with cerebral infarction in more than 80 per cent of patients.
Mangifera indica L. extract (Vimang®) reduces plasma and liver cholesterol and leucocyte oxidative stress in hypercholesterolemic LDL receptor deficient mice
Authors: Dorighello Gabriel G. , Inada Natália M. , Paim Bruno A. , Pardo‐Andreu Gilberto L. , Vercesi Anibal E. , Oliveira Helena C.F.
Published: February 2018

Cardiovascular diseases are major causes of death worldwide. Beyond the classical cholesterol risk factor, other conditions such as oxidative stress are well documented to promote atherosclerosis. The Mangifera indica L. extract (Vimang®) was reported to present antioxidant and hypocholesterolemic properties. Thus, here we evaluate the effects of Vimang treatment on risk factors of the atherosclerosis prone model of familial hypercholesterolemia, the LDL receptor knockout mice. Mice were treated with Vimang during 2 weeks and were fed a cholesterol‐enriched diet during the second week. The Vimang treated mice presented significantly reduced levels of plasma (15%) and liver (20%) cholesterol, increased plasma total antioxidant capacity (10%) and decreased reactive oxygen species (ROS) production by spleen mononuclear cells (50%), P < 0.05 for all. In spite of these benefits, the average size of aortic atherosclerotic lesions stablished in this short experimental period did not change significantly in Vimang treated mice. Therefore, in this study we demonstrated that Vimang has protective effects on systemic and tissue‐specific risk factors, but it is not sufficient to promote a reduction in the initial steps of atherosclerosis development. In addition, we disclosed a new antioxidant target of Vimang, the spleen mononuclear cells that might be relevant for more advanced stages of atherosclerosis.
Amidinate Aluminium Complexes as Catalysts for Carbon Dioxide Fixation into Cyclic Carbonates
Authors: Meléndez Danay Osorio , Lara‐Sánchez Agustín , Martínez Javier , Wu Xiao , Otero Antonio , Castro‐Osma José A. , North Michael , Rojas René S.
Published: February 2018

A series of inexpensive and sustainable amidinate aluminium complexes has been developed as catalysts for the chemical fixation of carbon dioxide into cyclic carbonates. The reactions using terminal epoxides as substrates were carried out at room temperature and one bar of carbon dioxide pressure in the presence of tetrabutylammonium iodide as cocatalyst in the absence of solvent. Under these reaction conditions, excellent conversions and selectivities were achieved for a broad range of terminal epoxides. Moreover, the optimal catalyst could be used for the synthesis of disubstituted cyclic carbonates from internal epoxides and carbon dioxide, highlighting the potential of these amidinate aluminium complexes as catalysts.
Crystal Nucleation of Tolbutamide in Solution: Relationship to Solvent, Solute Conformation, and Solution Structure
Authors: Zeglinski Jacek , Kuhs Manuel , Khamar Dikshitkumar , Hegarty Avril C. , Devi Renuka K. , Rasmuson Åke C.
Published: February 2018

The influence of the solvent in nucleation of tolbutamide, a medium‐sized, flexible and polymorphic organic molecule, has been explored by measuring nucleation induction times, estimating solvent–solute interaction enthalpies using molecular modelling and calorimetric data, probing interactions and clustering with spectroscopy, and modelling solvent‐dependence of molecular conformation in solution. The nucleation driving force required to reach the same induction time is strongly solvent‐dependent, increasing in the order: acetonitrile<ethyl acetate<n‐propanol<toluene. The combined DFT and MD modelling results show that in acetonitrile, ethyl acetate and n‐propanol the nucleation difficulty is a function of the strength of solvent–solute interaction, with emphasis on the interaction with specific H‐bonding polar sites of importance in the crystal structure. A clear exception from this rule is the most difficult nucleation in toluene despite the weakest solvent–solute interactions. However molecular dynamics modelling predicts that tolbutamide assumes an intramolecularly H‐bonded conformation in toluene, substantially different from and more stable than the conformation in the crystal structure, and thus presenting an additional barrier to nucleation. This explains why nucleation in toluene is the most difficult and why the relatively higher propensity for aggregation of tolbutamide molecules in toluene solution, as observed with FTIR spectroscopy, does not translate into easier nucleation. Thus, our combined experimental and molecular modelling study suggests that the solvent can influence on the nucleation not only via differences in the desolvation but also through the influence on molecular conformation.
Formation of Linear Side‐Chain Polypseudorotaxane with Supramolecular Polymer Backbone through Neutral Halogen Bonds and Pillar[5]arene‐Based Host–Guest Interactions
Authors: Liu Peiren , Li Zhengtao , Shi Bingbing , Liu Jiyong , Zhu Huangtianzhi , Huang Feihe
Published: February 2018

Linear side‐chain polypseudorotaxane with supramolecular polymer backbone was assembled by neutral halogen bonds (XB) and pillar[5]arene‐based host–guest interactions in solution and in the solid state. The formation of the halogen‐bonded supramolecular polymer backbone and side‐chain polypseudorotaxane in solution was characterized by 1H NMR spectroscopy, diffusion ordered NMR spectroscopy and scanning electron microscopy experiments. Furthermore, the solid‐state structures of these two highly organized supramolecular architectures were provided by single‐crystal X‐ray analysis.
Probing Ligand Structure–Activity Relationships in Pregnane X Receptor (PXR): Efavirenz and 8‐Hydroxyefavirenz Exhibit Divergence in Activation
Authors: Narayanan Bhargavi , Lade Julie M. , Heck Carley J. S. , Dietz Kevin D. , Wade Herschel , Bumpus Namandjé N.
Published: February 2018

Efavirenz (EFV), an antiretroviral that interacts clinically with co‐administered drugs via activation of the pregnane X receptor (PXR), is extensively metabolized by the cytochromes P450. We tested whether its primary metabolite, 8‐hydroxyEFV (8‐OHEFV) can activate PXR and potentially contribute to PXR‐mediated drug–drug interactions attributed to EFV. Luciferase reporter assays revealed that despite only differing from EFV by an oxygen atom, 8‐OHEFV does not activate PXR. Corroborating this, treatment with EFV for 72 h elevated the mRNA abundance of the PXR target gene, Cyp3a11, by approximately 28‐fold in primary hepatocytes isolated from PXR‐humanized mice, whereas treatment with 8‐OHEFV did not result in a change in Cyp3A11 mRNA levels. FRET‐based competitive binding assays and isothermal calorimetry demonstrated that even with the lack of ability to activate PXR, 8‐OHEFV displays an affinity for PXR (IC50 12.1 μm; KD 7.9 μm) nearly identical to that of EFV (IC50 18.7 μm; KD 12.5 μm). The use of 16 EFV analogues suggest that other discreet changes to the EFV structure beyond the 8‐position are well tolerated. Molecular docking simulations implicate an 8‐OHEFV binding mode that may underlie its divergence in PXR activation from EFV.
A hybrid interpretable credit card users default prediction model based on RIPPER
Authors: Xu Pu , Ding Zhijun , Pan MeiQin
Published: February 2018

With the vigorous development of the financial sector, financial risks are showing a tendency toward diversification, particularly regarding the customer credit risk of commercial banks. Therefore, the customer's credit risk is being considered by financial institutions, and a credit evaluating model has emerged as a result. Currently, research has concentrated on enhancing the precision of the model, ignoring the interpretability, which makes it difficult to apply in the industry. Compared to precision, studies related to the interpretable model are limited. In our previous work, we did not consider model operation time and stability. Therefore, this study proposes a hybrid model based on the RIPPER algorithm. First, according to the characteristics of credit card data sets, targeted special data pretreatment methods are proposed. Next, the RELIEF method for feature selection removes the redundant features and further improves the interpretability of the model. Then, to address the problem of the imbalanced distribution of credit card data sets, a synthetic minority class sampling algorithm is used to equalize the samples. Finally, default credit card users are predicted by taking advantage of the rules generated by the RIPPER algorithm. To test the performance of the model, we used Taiwanese credit card customer data for empirical research. We considered model accuracy and interpretability when comparing the proposed SPR‐RIPPER model with the existing mainstream models. The results of the experiments indicate that the proposed model achieves acceptable results. This study demonstrates that the proposed credit card user default prediction model, SPR‐RIPPER, has practical application value.
Thermophysical and Optical Properties of L‐Tartaric Acid Crystal
Authors: Jayapalan Thirupathy , Sathiyadhas Sahaya Jude Dhas , Michael Jose , Settu Balachandar , Sathiyadhas Amalapushpam Martin Britto Dhas
Published: February 2018

Thermal properties play a vital role particularly for the materials which are used in high power laser irradiation. Photoacoustic technique is very much feasible to findout the thermal transport properties of solid materials. In the present work, nonlinear optical (NLO) single crystal of L‐tartaric acid (LTA) was grown by Sankaranarayanan‐Ramasamy (SR) method for dimensions of 140 mm in length and 11.5 mm in diameter. The grown LTA crystal has been subjected to UV‐Vis‐NIR spectral study to analyze the optical transmittance and absorbance characteristics. The thermal characterization studies were performed using photoacoustic spectrometer (PAS). Thermal characterization involves measurement of thermal parameters such as thermal diffusivity, thermal effusivity, thermal conductivity and specific heat capacity. The experimental results of photoacoustic spectrometer show that the thermal diffusivity of LTA is higher than the reported values of a few other well known NLO materials.
Estimator learning automata for feature subset selection in high‐dimensional spaces, case study: Email spam detection
Authors: Seyyedi Seyyed Hossein , Minaei‐Bidgoli Behrouz
Published: February 2018

One of the difficult challenges facing data miners is that algorithm performance degrades if the feature space contains redundant or irrelevant features. Therefore, as a critical preprocess task, dimension reduction is used to build a smaller space containing valuable features. There are 2 different approaches for dimension reduction: feature extraction and feature selection, which itself is divided into wrapper and filter approaches. In high‐dimensional spaces, feature extraction and wrapper approaches are not applicable due to the time complexity. On the other hand, the filter approach suffers from inaccuracy. One main reason for this inaccuracy is that the subset's size is not determined considering specifications of the problem.

In this paper, we propose ESS (estimator learning automaton‐based subset selection) as a new method for feature selection in high‐dimensional spaces. The innovation of ESS is that it combines wrapper and filter ideas and uses estimator learning automata to efficiently determine a feature subset that leads to a desirable tradeoff between the accuracy and efficiency of the learning algorithm. To find a qualified subset for a special processing algorithm that functions on an arbitrary dataset, ESS uses an automaton to score each candidate subset upon the scale of the subset and accuracy of the learning algorithm using it. In the end, the subset with the highest score is returned. We have used ESS for feature selection in the framework of spam detection, a text classification task for email as a pervasive communication medium. The results show achievement in reaching the goal stated above.
Host–pathogen metapopulation dynamics suggest high elevation refugia for boreal toads
Authors: Mosher Brittany A. , Bailey Larissa L. , Muths Erin , Huyvaert Kathryn P.
Published: February 2018

Emerging infectious diseases are an increasingly common threat to wildlife. Chytridiomycosis, caused by the fungal pathogenBatrachochytrium dendrobatidis(Bd), is an emerging infectious disease that has been linked to amphibian declines around the world. Few studies exist that explore amphibian–Bddynamics at the landscape scale, limiting our ability to identify which factors are associated with variation in population susceptibility and to develop effective in situ disease management. Declines of boreal toads (Anaxyrus boreas boreas) in the southern Rocky Mountains are largely attributed to chytridiomycosis but variation exists in local extinction of boreal toads across this metapopulation. Using a large‐scale historic data set, we explored several potential factors influencing disease dynamics in the boreal toad–Bdsystem: geographic isolation of populations, amphibian community richness, elevational differences, and habitat permanence. We found evidence that boreal toad extinction risk was lowest at high elevations where temperatures may be suboptimal forBdgrowth and where small boreal toad populations may be below the threshold needed for efficient pathogen transmission. In addition, boreal toads were more likely to recolonize high elevation sites after local extinction, again suggesting that high elevations may provide refuge from disease for boreal toads. We illustrate a modeling framework that will be useful to natural resource managers striving to make decisions in amphibian–Bdsystems. Our data suggest that in the southern Rocky Mountains high elevation sites should be prioritized for conservation initiatives like reintroductions.
Oceanographic variation influences spatial genomic structure in the sea scallop, Placopecten magellanicus
Authors: Van Wyngaarden Mallory , Snelgrove Paul V. R. , DiBacco Claudio , Hamilton Lorraine C. , Rodríguez‐Ezpeleta Naiara , Zhan Luyao , Beiko Robert G. , Bradbury Ian R.
Published: February 2018

Environmental factors can influence diversity and population structure in marine species and accurate understanding of this influence can both improve fisheries management and help predict responses to environmental change. We used 7163 SNPs derived from restriction site‐associated DNA sequencing genotyped in 245 individuals of the economically important sea scallop, Placopecten magellanicus, to evaluate the correlations between oceanographic variation and a previously identified latitudinal genomic cline. Sea scallops span a broad latitudinal area (>10 degrees), and we hypothesized that climatic variation significantly drives clinal trends in allele frequency. Using a large environmental dataset, including temperature, salinity, chlorophyll a, and nutrient concentrations, we identified a suite of SNPs (285–621, depending on analysis and environmental dataset) potentially under selection through correlations with environmental variation. Principal components analysis of different outlier SNPs and environmental datasets revealed similar northern and southern clusters, with significant associations between the first axes of each (R2adj = .66–.79). Multivariate redundancy analysis of outlier SNPs and the environmental principal components indicated that environmental factors explained more than 32% of the variance. Similarly, multiple linear regressions and random‐forest analysis identified winter average and minimum ocean temperatures as significant parameters in the link between genetic and environmental variation. This work indicates that oceanographic variation is associated with the observed genomic cline in this species and that seasonal periods of extreme cold may restrict gene flow along a latitudinal gradient in this marine benthic bivalve. Incorporating this finding into management may improve accuracy of management strategies and future predictions.
Nutritional geometry and fitness consequences in Drosophila suzukii, the Spotted‐Wing Drosophila
Authors: Young Yvonne , Buckiewicz Natasha , Long Tristan A. F.
Published: February 2018

Since its arrival to North America less than a decade ago, the invasive Spotted‐Wing Drosophila (Drosophila suzukii) has inflicted substantial economic losses on soft fruit agriculture due to its ability to oviposit into ripening fruits. More effective management approaches for this species are needed, but little is known about the factors that influence behavioral choices made by D. suzukii when selecting hosts, or the consequences that their offspring experience when developing in different environments. Using a nutritional geometry methodology, we found that the ratio of proteins‐to‐carbohydrates (P:C) present in media greatly influenced adult D. suzukii behavior and subsequent offspring development. Whereas adult flies showed a strong bias in their oviposition and association behaviors toward carbohydrate‐rich foods, larval survival and eclosion rate were strongly dependent on protein availability. Here, we explore the preference–performance hypothesis (PPH), in which females are predicted to oviposit on medias that provide the greatest offspring benefits, in regard to its relevance in D. suzukii behavior and consequences for management. Our results provide valuable insight into the ecology and evolution of this species that may hopefully lead to more effective management strategies.
Conceptual toolboxes for twenty‐first‐century ecologists
Authors: Reiners William A. , Pappas Gregory S. , Lockwood Jeffrey A. , Reiners Derek S. , Prager Steven D.
Published: February 2018

We ecologists realize that individually we have a variety of interests, knowledge, and skills among us; and we appreciate how those attributes differentially apply to the diverse tasks we address in our various “practices” of ecology. Less obvious to us, however, is the variety of intellectual tools we bring to bear in our practices. In order to understand how members of our discipline “think” as well as “know” and “act,” this paper explores how the utility of ecological concepts varies among ecologists and how concepts tend to be lumped into what might be viewed as cognitive “toolkits” for implementing our work. Knowing the character of these metaphorical toolkits helps us to understand the nature of our discipline, to better teach ecology, and to more effectively communicate with one another. We collected “usefulness” ratings of 131 normative concepts (i.e., what an ecologist ought to know) through an Ecological Society of America‐wide survey and analyzed results through cluster analysis. Ten concept clusters emerged, each having varying numbers of concepts and various degrees of subject matter cohesion. Only some of these resembled commonly recognized specializations in ecology. General descriptors for these clusters are as follows: general ecology, population ecology, community ecology, evolutionary ecology, ecosystem ecology, biogeochemistry, spatial structures, scaling structure and function, cross‐system structures, and cross‐system dynamics.
Effect of sacubitril/valsartan on recurrent events in the Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortality and morbidity in Heart Failure trial (PARADIGM‐HF)
Authors: Mogensen Ulrik M. , Gong Jianjian , Jhund Pardeep S. , Shen Li , Køber Lars , Desai Akshay S. , Lefkowitz Martin P. , Packer Milton , Rouleau Jean L. , Solomon Scott D. , Claggett Brian L. , Swedberg Karl , Zile Michael R. , Mueller‐Velten Guenther , McMurray John J.V.
Published: February 2018

Aims

Recurrent hospitalizations are a major part of the disease burden in heart failure (HF), but conventional analyses consider only the first event. We compared the effect of sacubitril/valsartan vs. enalapril on recurrent events, incorporating all HF hospitalizations and cardiovascular (CV) deaths in PARADIGM‐HF, using a variety of statistical approaches advocated for this type of analysis.

Methods and results

In PARADIGM‐HF, a total of 8399 patients were randomized and followed for a median of 27 months. We applied various recurrent event analyses, including a negative binomial model, the Wei, Lin and Weissfeld (WLW), and Lin, Wei, Ying and Yang (LWYY) methods, and a joint frailty model, all adjusted for treatment and region. Among a total of 3181 primary endpoint events (including 1251 CV deaths) during the trial, only 2031 (63.8%) were first events (836 CV deaths). Among a total of 1195 patients with at least one HF hospitalization, 410 (34%) had at least one further HF hospitalization. Sacubitril/valsartan compared with enalapril reduced the risk of recurrent HF hospitalization using the negative binomial model [rate ratio (RR) 0.77, 95% confidence interval (CI) 0.67–0.89], the WLW method [hazard ratio (HR) 0.79, 95% CI 0.71–0.89], the LWYY method (RR 0.78, 95% CI 0.68–0.90), and the joint frailty model (HR 0.75, 95% CI 0.66–0.86) (all P < 0.001). The effect of sacubitril/valsartan vs. enalapril on recurrent HF hospitalizations/CV death was similar.

Conclusions

In PARADIGM‐HF, approximately one third of patients with a primary endpoint (time‐to‐first) experienced a further event. Compared with enalapril, sacubitril/valsartan reduced both first and recurrent events. The treatment effect size was similar, regardless of the statistical approach applied.
CXCR4–CXCL12 interaction is important for plasma cell homing and survival in NZB/W mice
Authors: Cheng Qingyu , Khodadadi Laleh , Taddeo Adriano , Klotsche Jens , F. Hoyer Bimba , Radbruch Andreas , Hiepe Falk
Published: February 2018

Antibody‐secreting cells (ASCs), including short‐lived plasmablasts and long‐lived memory plasma cells (LLPCs), contribute to autoimmune pathology. ASCs, particularly LLPCs, refractory to conventional immunosuppressive drugs pose a major therapeutic challenge. Since stromal cells expressing C‐X‐C motif chemokine‐12 (CXCL12) organize survival niches for LLPCs in the bone marrow, we investigated the effects of CXCL12 and its ligand CXCR4 (C‐X‐C chemokine receptor 4) on ASCs in lupus mice (NZB/W). Fewer adoptively transferred splenic ASCs were retrieved from the bone marrow of recipient immunodeficient Rag1−/− mice when the ASCs were pretreated with the CXCR4 blocker AMD3100. CXCR4 blockade also significantly reduced anti‐OVA ASCs in the bone marrow after secondary immunization with OVA. In this study, AMD3100 efficiently depleted ASCs, including LLPCs. After two weeks, it decreased the total number of ASCs in the spleen and bone marrow by more than 60%. Combination with the proteasome inhibitor bortezomib significantly enhanced the depletion effect of AMD3100. Continuous long‐term (five‐month) CXCR4 blockade with AMD3100 after effective short‐term LLPCs depletion kept the number of LLPCs in the bone marrow low, delayed proteinuria development and prolonged the survival of the mice. These findings identify the CXCR4‐CXCL12 axis as a potential therapeutic target likely due to its importance for ASC homing and survival.
Nanoparticle‐based approaches to immune tolerance for the treatment of autoimmune diseases
Authors: Serra Pau , Santamaria Pere
Published: February 2018

Autoimmune diseases are caused by antigenically complex immune responses of the adaptive and innate immune system against specific cells, tissues or organs. Antigen‐specific approaches for induction of immune tolerance in autoimmunity, based on the use of antigenic peptides or proteins, have failed to deliver the desired therapeutic results in clinical trials. These approaches, which are largely relying on triggering clonal anergy and/or deletion of defined autoreactive specificities, do not address the overwhelming antigenic, molecular, and cellular complexity of most autoimmune diseases, which involve various immune cells and ever‐growing repertoires of antigenic epitopes on numerous self‐antigens. Advances in the field of regulatory T‐cell (Treg) biology have suggested that Treg cells might be able to afford dominant tolerance provided they are properly activated and expanded in vivo. More recently, nanotechnology has introduced novel technical advances capable of modulating immune responses. Here, we review nanoparticle‐based approaches designed to induce immune tolerance, ranging from approaches that primarily trigger clonal T‐cell anergy or deletion to approaches that trigger Treg cell formation and expansion from autoreactive T‐cell effectors. We will also highlight the therapeutic potential and positive outcomes in numerous experimental models of autoimmunity.
Synthesis of Actinide Fluoride Complexes Using Trimethyltin Fluoride as a Mild and Selective Fluorinating Reagent
Authors: Kagan Benjamin D. , Lichtscheidl Alejandro G. , Erickson Karla A. , Monreal Marisa J. , Scott Brian L. , Nelson Andrew T. , Kiplinger Jaqueline L.
Published: February 2018

Invited for the cover of this issue are JaquelineàL. Kiplinger and co‐workers from Los Alamos National Laboratory, New Mexico, USA. The cover image shows the versatility of trimethyltin fluoride (Me3SnF) as a reagent for the conversion of actinide halides to actinide fluorides.
An Efficient Synthesis of N,N,N‐Substituted 1,4,7‐Triazacyclononane
Authors: Huang Yong , Liu Yajing , Liu Song , Wu Renbo , Wu Zehui
Published: February 2018

A new and efficient synthetic approach is reported for various N,N,N‐substituted 1,4,7‐triazacyclononanes (TACN) in moderate to excellent yields, with optimization of the reaction sequences and conditions of the intermediate 1,4,7‐tribenzyl‐1,4,7‐triazonane‐2,6‐dione reduction with LiAlH4, removal of benzyl with Pd/C, and alkylation reactions. This reaction scheme provides a convenient and flexible method to prepare various N,N,N‐substituted TACN derivatives.
Modelling feedbacks between geomorphological and riparian vegetation responses under climate change in a Mediterranean context
Authors: Martínez‐Fernández Vanesa , Van Oorschot Mijke , De Smit Jaco , González del Tánago Marta , Buijse Anthonie D.
Published: February 2018

Climate change is expected to alter temperatures and precipitation patterns, affecting river flows and hence riparian corridors. In this context we have explored the potential evolution of riparian corridors under a dryness gradient of flow regimes associated with climate change in a Mediterranean river. We have applied an advanced bio‐hydromorphodynamic model incorporating interactions between hydro‐morphodynamics and vegetation. Five scenarios, representing drier conditions and more extreme events, and an additional reference scenario without climate change, have been designed and extended until the year 2100. The vegetation model assesses colonization, growth and mortality of Salicaceae species. We analysed the lower course of the Curueño River, a free flowing gravel bed river (NW Spain), as a representative case study of the Mediterranean region.

Modelling results reveal that climate change will affect both channel morphology and riparian vegetation in terms of cover, age distribution and mortality. Reciprocal interactions between flow conditions and riparian species as bio‐engineers are predicted to promote channel narrowing, which becomes more pronounced as dryness increases. Reductions in seedling cover and increases in sapling and mature forest cover are predicted for all climate change scenarios compared with the reference scenario, and the suitable area for vegetation development declines and shifts towards lower floodplain elevations. Climate change also leads to younger vegetation becoming more subject to uprooting and flooding. The predicted reduction in suitable establishment areas and the narrowing of vegetated belts threatens the persistence of the current riparian community. This study highlights the usefulness of advanced bio‐hydromorphodynamic modelling for assessing climate change effects on fluvial landscapes. It also illustrates the need to consider climate change in river management to identify appropriate adaptation measures for riparian ecosystems. Copyright © 2018 John Wiley & Sons, Ltd.
NUP98‐BPTF gene fusion identified in primary refractory acute megakaryoblastic leukemia of infancy
Authors: Roussy Mathieu , Bilodeau Mélanie , Jouan Loubna , Tibout Pauline , Laramée Louise , Lemyre Emmanuelle , Léveillé France , Tihy Frédérique , Cardin Sophie , Sauvageau Camille , Couture Françoise , Louis Isabelle , Choblet Aurélien , Patey Natalie , Gendron Patrick , Duval Michel , Teira Pierre , Hébert Josée , Wilhelm Brian T. , Choi John K. , Gruber Tanja A. , Bittencourt Henrique , Cellot Sonia
Published: February 2018

The advent of large scale genomic sequencing technologies significantly improved the molecular classification of acute megakaryoblastic leukaemia (AMKL). AMKL represents a subset (∼10%) of high fatality pediatric acute myeloid leukemia (AML). Recurrent and mutually exclusive chimeric gene fusions associated with pediatric AMKL are found in 60%‐70% of cases and include RBM15‐MKL1, CBFA2T3‐GLIS2, NUP98‐KDM5A and MLL rearrangements. In addition, another 4% of AMKL harbor NUP98 rearrangements (NUP98r), with yet undetermined fusion partners. We report a novel NUP98‐BPTF fusion in an infant presenting with primary refractory AMKL. In this NUP98r, the C‐terminal chromatin recognition modules of BPTF, a core subunit of the NURF (nucleosome remodeling factor) ATP‐dependent chromatin‐remodeling complex, are fused to the N‐terminal moiety of NUP98, creating an in frame NUP98‐BPTF fusion, with structural homology to NUP98‐KDM5A. The leukemic blasts expressed two NUP98‐BPTF splicing variants, containing one or two tandemly spaced PHD chromatin reader domains. Our study also identified an unreported wild type BPTF splicing variant encoding for 2 PHD domains, detected both in normal cord blood CD34+ cells and in leukemic blasts, as with the fly BPTF homolog, Nurf301. Disease course was marked by rapid progression and primary chemoresistance, with ultimately significant tumor burden reduction following treatment with a clofarabine containing regimen. In sum, we report 2 novel NUP98‐BPTF fusion isoforms that contribute to refine the NUP98r subgroup of pediatric AMKL. Multicenter clinical trials are critically required to determine the frequency of this fusion in AMKL patients and explore innovative treatment strategies for a disease still plagued with poor outcomes.
Continuously infused amphotericin B deoxycholate for primary treatment of invasive fungal disease in acute myeloid leukaemia
Authors: Rothenbühler Christoph , Held Ulrike , Manz Markus G. , Schanz Urs , Gerber Bernhard
Published: February 2018

Continuous administration of amphotericin B deoxycholate over 24 hours (24 h‐D‐AmB) is better tolerated than rapid infusions. However, toxicity and outcome have not been assessed in a homogenous patient population with acute myeloid leukaemia (AML). We retrospectively analysed renal function and outcome in all adult patients with AML undergoing intensive chemotherapy between 2007 and 2012 at our institution. We compared a patient group with exposure to 24 h‐D‐AmB to a patient group without exposure to 24 h‐D‐AmB. One hundred and eighty‐one consecutive patients were analysed, 133 (73.5%) received at least 1 dose of 24 h‐D‐AmB, and 48 (26.5%) did not. Reasons for 24 h‐D‐AmB initiation were invasive fungal disease (IFD) in 63.5% and empirical treatment for febrile neutropenia in 36.5% of the cases. Most patients with IFD received an oral triazole drug at hospital discharge. Baseline characteristics were well matched. Amphotericin B deoxycholate over 24 hours was given for a median 7 days (interquartile range 3‐13). Peak creatinine concentration was higher in the 24 h‐D‐AmB‐group (104.5 vs. 76 μmol/L, P < .001) but normalized within 1 month after therapy (65.5 vs. 65 μmol/L, P = .979). In neither of the 2 groups, end‐stage renal disease occurred. There was no difference in 60‐day survival (90% vs. 90%) and 2‐year survival (58% vs. 58%). Invasive fungal disease partial response or better was observed in 68% of the patients. We conclude that antifungal therapy with continuously infused amphotericin B deoxycholate is safe in patients with AML. An antiinfective strategy based on 24 h‐D‐AmB in first line followed by an oral triazole compound represents an economically attractive treatment option.