bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and characterization of Ni(II) complexes bearing of 2‐(1H–benzimidazol‐2‐yl)‐phenol derivatives as highly active catalysts for ethylene oligomerization
Authors: Haghverdi Marzieh , Tadjarodi Azadeh , Bahri‐Laleh Naeimeh , Nekoomanesh‐Haghighi Mehdi
Published: October 2017

Novel Ni(II) complexes of 2‐(1H–benzimidazol‐2‐yl)‐phenol derivatives (HLx: x  =  1–5; C1–C5) have been synthesized and characterized. In the mononuclear complexes, the ligands were coordinated as bidentate, via one imine nitrogen and the phenolate oxygen atoms. The structures of the compounds were confirmed on the basis of FT‐IR, UV–Vis, 1H‐, 13C–NMR, inductively coupled plasma and elemental analyses (C, H and N). The purity of these compounds was ascertained by melting point (m.p.) and thin‐layer chromatography. The geometry optimization and vibrational frequency calculations of the compounds were performed using Gaussian 09 program with B3LYP/TZVP level of theory. All Ni(II) complexes were activated with diethylaluminum chloride (Et2AlCl), so that C2 showed the highest activity [6600 kg mol−1 (Ni) h−1], where the ligand contains a chlorine substituent. Oligomers obtained from the complexes consist mainly of dimer and trimer, and also exhibit high selectivity for linear 1‐butene and 1‐hexene. Both the steric and electronic effects of coordinative ligands affect the catalytic activity and the properties of the catalytic products.
The aggregation structure regulation of lignin by chemical modification and its effect on the property of lignin/styrene–butadiene rubber composites
Authors: Jiang Can , He Hui , Yao Xiaojie , Yu Peng , Zhou Ling , Jia Demin
Published: October 2017

The aggregation structure of lignin in aqueous solution had an important effect on the dispersion of lignin and the properties of lignin/styrene–butadiene rubber (SBR) composites. This article revealed the relationship between aggregation structure and chemical structure of modified lignin. Unmodified lignin was amorphous; however, our results showed that aldehyde‐modified lignin was transformed into spherical aggregates, while propylene‐oxide‐modified lignin self‐aggregated into supramolecular domains. The relationships between aggregation structure, filler dispersion, filler–rubber interaction, and performance were also studied by investigating the microstructure, viscoelastic behavior, and mechanical properties of lignin/SBR composites. Meanwhile, a solution to improve the coprecipitation efficiency of lignin and SBR latex was proposed. In this article, epoxidized natural rubber (ENR) was also used as compatibilizer to improve the interfacial adhesion between polar lignin and nonpolar SBR. The results showed better lignin dispersion for the ENR‐containing rubber composites, as well as superior wet skid resistance and lower rolling resistance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45759.
Oxo‐biodegradability of high‐density polyethylene films containing limited amount of isotactic polypropylene
Authors: Khajehpour‐Tadavani Soheyl , Nejabat Gholam‐Reza , Mortazavi Seyed Mohammad Mahdi
Published: October 2017

Limited amount of isotactic polypropylene (iPP) is added to high‐density polyethylene (HDPE) containing 1% w/w an oxo‐biodegradable additive and extruded and converted to films. The films are put under UV irradiation for different periods of time. Irradiation of the films for 6 weeks imposes remarkable effects on viscosity average molecular weight (Mv) and carbonyl index (CI) of them. Mv decreases from 3.4 × 105 to 4.7 × 104 g mol−1 for neat HDPE films; from 3.1 × 105 to 3.3 × 104 g mol−1 for the films containing oxo compound, and from 1.5 × 105 to 2.6 × 104 g mol−1 for the films containing oxo compound and 1% w/w iPP. Carbonyl index of the neat HDPE films increases from 4 to 8.7 while for the sample containing only the oxo compound it increases from 4.5 to 7.3 and for the sample containing both oxo compound and iPP it decreases from 12.0 to 8.8. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) indicate more cracks and uniform degradation in the samples containing iPP and oxo compound. Thermogravimetric analysis (TGA/DTG) of the samples shows that the samples containing iPP and oxo compound have lower decomposition temperature after UV irradiation. Finally, it can be said that the presence of iPP in HDPE matrix containing oxo compound can improve HDPE oxo‐biodegradablity. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45843.
Photoelectrochemical Complexes of Fucoxanthin‐Chlorophyll Protein for Bio‐Photovoltaic Conversion with a High Open‐Circuit Photovoltage
Authors: Zhang Tianning , Liu Cheng , Dong Wenjing , Wang Wenda , Sun Yan , Chen Xin , Yang Chunhong , Dai Ning
Published: October 2017

Open‐circuit photovoltage (Voc) is among the critical parameters for achieving an efficient light‐to‐charge conversion in existing solar photovoltaic devices. Natural photosynthesis exploits light‐harvesting chlorophyll (Chl) protein complexes to transfer sunlight energy efficiently. We describe the exploitation of photosynthetic fucoxanthin‐chlorophyll protein (FCP) complexes for realizing photoelectrochemical cells with a high Voc. An antenna‐dependent photocurrent response and a Voc up to 0.72 V are observed and demonstrated in the bio‐photovoltaic devices fabricated with photosynthetic FCP complexes and TiO2 nanostructures. Such high Voc is determined by fucoxanthin in FCP complexes, and is rarely found in photoelectrochemical cells with other natural light‐harvesting antenna. We think that the FCP‐based bio‐photovoltaic conversion will provide an opportunity to fabricate environmental benign photoelectrochemical cells with high Voc, and also help improve the understanding of the essential physics behind the light‐to‐charge conversion in photosynthetic complexes.
Characterization of Stochastic Mean‐Field Type Index
Authors: Ma Limin , Li Yan , Zhang Tianliang
Published: October 2017

index of mean‐field stochastic differential equations (SDE) is investigated in this paper. For systems with state‐ and input‐dependent noise, we obtain a sufficient condition of
index larger than some λ>0 via the solvability of differential Riccati equations (DRE). Especially, a necessary and sufficient condition is given for mean‐field SDE with state‐dependent noise, which generalize the corresponding results of classical stochastic systems to the mean‐field stochastic models.
Trans‐acting oligodeoxythymidine phosphorothioate triester reagents for transient transfection optimized and facilitated by a high‐throughput microbioreactor system
Authors: Hsu Chih‐Jung , Jain Harsh V. , Williams Abasha , Wang Julie , Lute Scott C. , Beaucage Serge L. , Brorson Kurt A.
Published: October 2017

A rapid and cost‐effective transient transfection method for mammalian cells is essential for screening biopharmaceuticals in early stages of development. A library of 25 amphipathic trans‐acting oligodeoxythymidine phosphorothioate triester (dTtaPS) transfection reagents, carrying positively charged and lipophilic groups, has been constructed for this purpose. High‐throughput screening of the library, using an imaging cytometer and an automated microbioreactor system, has led to the identification of dTtaPS10+ as a potent transfection reagent. This reagent efficiently delivers a plasmid encoding enhanced green fluorescent protein in adherent HeLa cells while exhibiting low cytotoxicity. The microbioreactor system has been particularly useful for assessing the ability of dTtaPS10+ to deliver a plasmid encoding immunoglobulin IgG1 in a fed‐batch serum‐free suspension CHO cell culture; dTtaPS10+‐mediated transfection resulted in the production of IgG1 in yields comparable to or better than those obtained with commercial lipid‐based transfection reagents under similar conditions. The ability of dTtaPS10+ to deliver plasmids is essentially unaffected by the presence of a silicone‐based antifoaming reagent, which is commonly used in bioreactor cell cultures. The transfection efficiency of lyophilized dTtaPS10+‐plasmid complexes has been significantly restored upon aqueous reconstitution when compared to that achieved while using commercial transfection reagent complexes under similar conditions. The results of all experiments underscore the potential of dTtaPS10+ for transient transfection of plasmids into adherent cells and fed‐batch serum‐free suspension CHO cells and rapid screening of reagents in a microbioreactor system.
Strengths, challenges, and opportunities for hydrothermal pretreatment in lignocellulosic biorefineries
Authors: Yang Bin , Tao Ling , Wyman Charles E.
Published: October 2017

Pretreatment prior to or during biological conversion is required to achieve high sugar yields essential to economic production of fuels and chemicals from low cost, abundant lignocellulosic biomass. Aqueous thermochemical pretreatments achieve this performance objective from pretreatment coupled with subsequent enzymatic hydrolysis, but chemical pretreatment can also suffer from additional costs for exotic materials of construction, the need to recover or neutralize the chemicals, introduction of compounds that inhibit downstream operations, and waste disposal, as well as for the chemicals themselves. The simplicity of hydrothermal pretreatment with just hot water offers the potential to greatly improve the cost of the entire conversion process if sugar degradation during pretreatment, production of un‐fermentable oligomers, and the amount of expensive enzymes needed to obtain satisfactory yields from hydrothermally pretreated solids can be reduced. Biorefinery economics would also benefit if value could be generated from lignin and other components that are currently fated to be burned for power. However, achieving these goals will no doubt require development of advanced hydrothermal pretreatment configurations. For example, passing water through a stationary bed of lignocellulosic biomass in a flowthrough configuration achieves very high yields of hemicellulose sugars, removes more than 75% of the lignin for potential valorization, and improves sugar release from the pretreated solids with lower enzyme loadings. Unfortunately, the large quantities of water needed to achieve this performance result in very dilute sugars, high energy costs for pretreatment and product recover, and large amounts of oligomers. Thus, improving our understanding of hydrothermal pretreatment fundamentals is needed to gain insights into R&D opportunities to improve performance, and help identify novel configurations that lower capital and operating costs and achieve higher yields. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Syngas biomethanation: state‐of‐the‐art review and perspectives
Authors: Grimalt‐Alemany Antonio , Skiadas Ioannis V. , Gavala Hariklia N.
Published: October 2017

Significant research efforts are currently being made worldwide to develop more efficient biomethane production processes from a variety of waste streams. The biomethanation of biomass‐derived syngas can contribute to increasing the potential of methane production as it opens the way for the conversion of recalcitrant biomasses, generally not fully exploitable by anaerobic digestion systems. Additionally, this biological process presents several advantages over its analogous process of catalytic methanation such as the use of inexpensive biocatalysts, milder operational conditions, higher tolerance to the impurities of syngas, and higher product selectivity. However, there are still several challenges to be addressed for this technology to reach commercial stage. This work reviews the progress made over the last few years in syngas biomethanation processes in order to provide an overview of the current state of the art of this technology. The most relevant aspects determining the performance of syngas biomethanation processes are extensively discussed here, including microbial diversity and metabolic interactions in mixed microbial consortia, the influence of operating parameters and bioreactor designs, and the potential of modelling as a tool for the design and control of this bioprocess. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Regulation of Amyloid Fibril Formation from Human Islet Amyloid Polypeptide by a Ligand Binding to the Fusion of FK506‐binding Protein and the Insertion‐in‐Flap Domain
Authors: Yoon Soyoung , Kim Soohyun , Im Hana , Lee Kyunghee
Published: October 2017

Human islet amyloid polypeptide (hIAPP) is converted to toxic aggregates in type‐2 diabetes (T2D). With the aim of developing a candidate agent regulating hIAPP amyloid fibril formation, we constructed a series of recombinant fusion proteins using a bacterial expression system. FKBPIF‐L23‐hIAPP and F36VIF‐L23‐hIAPP accelerated amyloid fibril formation. Assays of cis/trans‐peptidyl‐prolyl isomerase activity as well as chaperone activity of FKBPIF‐L23‐hIAPP fusion proteins suggested that amyloid fibrils were produced because the chaperone activity of FKBPIF in the form of fusion protein was diminished. Moreover, addition of FK506, a binding ligand, slowed down the process of amyloid fibril formation in FKBPIF‐L23‐hIAPP fusion protein. Deletion mutant analysis of the insertion‐in‐flap (IF) domain revealed that the C‐terminal half is essential for acceleration of amyloid fibril formation. Based on these observations, we suggested a potential anti‐T2D therapeutic strategy by means of a small ligand and fragments of the IF domain inserted in a fusion protein.
Neurologists dealing with sickness certification: Experiences of problems and need of competence
Authors: Snöljung Åsa , Kärrholm Jenny , Hinas Elin , Alexanderson Kristina
Published: October 2017

Rationale and Aims

Most studies on physicians' sickness certification practices include general practitioners (GP) while there hardly is any knowledge on this regarding neurologists although neurological diseases often involve work incapacity and need of sick leave.

Aim

The aim was to describe experiences among neurologists in Sweden concerning their work with sickness certification of patients.

Method

A cross‐sectional study of 265 neurologists' responses in a nationwide survey regarding their work with sickness certification of patients was conducted.

Results

The majority (81.5%) had sickness certification consultations at least once a week and a third experienced problems every week in handling sickness certification. Among the 251 who at least sometimes had sickness certification consultations, the following two aspects were experienced as very or fairly problematic: “assess the degree to which the reduced functional capacity limits a patient's capacity to perform his/her work assignments” (67.3%) and “make a long‐term prognosis about the future work capacity of patients on sick leave” (60.5%). At least once a week, 78.7% experienced lack of time regarding managing patient‐related aspects of the sickness certification task. Moreover, 21.8% considered sickness certification to be a work environmental problem, at least once a week. In all, 84% stated that they had a large or fairly large need for more competence concerning sickness certification tasks.

Conclusions

Sickness certification is a common task among neurologists, involving several problematic aspects related to, e.g., lack of competence in assessing function and work capacity and of time. There is a need for improvement.
Never truly alone, we always have our purchases: Loneliness and sex as predictors of purchase attachment and future purchase intentions
Authors: Mittal Sarah , Silvera David H.
Published: October 2017

The meaning of a purchase does not end at “buy.” Past purchases can become integral to consumers' self‐definition and communication of their “self” to others. Just as consumers display differential attachment tendencies for material purchases, so too should they exhibit differences in experiential purchase attachment propensities. This research examines this issue and contributes to the literature on purchase attachment by examining individual differences in material versus experiential attachment tendencies. Specifically, this work shows that loneliness increases attachment to purchases that affirm one's social self and restore a sense of connection to others; however, the type of purchase that best achieves this social affirmation goal varies as a function of the consumer's sex. Females (males) are more likely to think about their material (experiential) purchases as representative of their relationships with others; therefore, lonely females (males) are more likely to attach to material (experiential) purchases. Across 5 studies, we demonstrate this sex by loneliness interaction and investigate the perceived effectiveness of material/experiential purchases as social cues, as a mechanism underlying these effects. Furthermore, we demonstrate that these attachment patterns influence future purchase tendencies—material (experiential) attachment predicts continued spending of disposable income on material (experiential) purchases.
Down‐regulation of LncRNA CCAT1 enhances radiosensitivity via regulating miR‐148b in breast cancer
Authors: Lai Yong , Chen Yang , Lin Yuanhong , Ye Ling
Published: October 2017

LncRNA colon‐cancer‐associated transcript‐1 (CCAT1) was proved to be a potential prognostic biomarker for breast cancer progression. However, the role of CCAT1 in regulating radiosensitivity of breast cancer and its underlying mechanism have not been investigated. The present study showed that CCAT1 was up‐regulated and miR‐148b was down‐regulated in radioresistant breast cancer tissues compared with radiosensitive breast cancer tissues. Radiation treatment triggered a significant increase in CCAT1 and an obvious decrease in miR‐148b. CCAT1 down‐regulation reduced colony formation rates and caspase3 activity in breast cancer cells under irradiation. Moreover, CCAT1 could negatively regulate miR‐148b expression. Furthermore, overexpression of miR‐148b suppressed colony survival fraction and caspase3 expression under irradiation in breast cancer cells, which was exacerbated by CCAT1 knockdown. Taken together, this study demonstrated that CCAT1 down‐regulation improved radiosensitivity of breast cancer cells via negatively regulating miR‐148b expression, providing a crucial clue for lncRNA‐miRNA interaction in the mechanism of radiosensitivity of breast cancer.
Flavin Photocatalysts for Visible‐Light [2+2] Cycloadditions: Structure, Reactivity and Reaction Mechanism
Authors: Mojr Viktor , Pitrová Gabriela , Straková Karolína , Prukała Dorota , Brazevic Sabina , Svobodová Eva , Hoskovcová Irena , Burdziński Gotard , Slanina Tomáš , Sikorski Marek , Cibulka Radek
Published: October 2017

New photocatalysts from the flavin family were found to mediate the [2+2] photocycloaddition reaction. 3‐Butyl‐10‐methyl‐5‐deazaflavin (3 a) and 1‐butyl‐7,8‐dimethoxy‐3‐methylalloxazine (2 e), if irradiated by visible light, were shown to allow an efficient (Φ≈3–10 %) intramolecular cyclisation of various types of substrates including substituted styrene dienes and bis(aryl enones), considered as electron‐rich and electron‐poor substrates, respectively, without any additional reagent. The versatility of the procedure was demonstrated by the cyclisation of photosensitive cinnamyl (E)‐3‐iodoallyl ether. Structure–activity studies found alloxazine 2 e was more active than 7‐monosubstituted (R=Cl, Br and MeO) alloxazines. The introduction of chlorine and bromine atom on the deazaflavin skeleton did not enhance the catalytic efficiency of 3 a. A detailed electrochemical and spectroscopic study explains the reaction mechanism proceeding through energy transfer from the flavin excited triplet state to the diene followed by its cyclisation.
Facile and Controllable One‐Pot Synthesis of Hierarchical Co9S8 Hollow Microspheres as High‐Performance Electroactive Materials for Energy Storage and Conversion
Authors: Lin Tsung‐Wu , Tsai Hong‐Chi , Chen Ting‐Yu , Shao Li–Dong
Published: October 2017

Hierarchical Co9S8 hollow microspheres with nanosheet building units are synthesized via a one‐step hydrothermal method. The presence of glucose in the synthesis is essential to the formation of the hollow structure and influences the size and morphology of the microspheres. Benefiting from the advantages of a hollow architecture, a conductive carbon coating and Co9S8 nanosheet units, the composite exhibits outstanding electrochemical properties. When the composite electrode is evaluated as the cathode material for supercapacitors, it exhibits a high specific capacitance of 514 F g−1 at 1.0 A g−1 and a capacitance retention of circa 88 % over 1000 cycles at 8 A g−1. On the other hand, the nanosheet‐constructed hollow structure can efficiently promote the electrocatalytic activity of Co9S8 toward the oxygen evolution reaction. Due to the fact that Co9S8 nanosheets impart largely exposed active sites, the composite exhibits a low Tafel slope of 66 mV dec−1 and no obvious degradation after 12 h water oxidation.
Highly Active and Readily Accessible Proline‐Based Dizinc Catalyst for CO2/Epoxide Copolymerization
Authors: Schütze Mike , Dechert Sebastian , Meyer Franc
Published: October 2017

In the pursuit of CO2‐based materials, the development of efficient catalysts for the alternating copolymerization of CO2 and epoxides to give polycarbonates is receiving particular attention. Desirable attributes for such catalysts are high copolymerization activity at low CO2 pressure, as well as chemo‐ and stereocontrol over the formed polymer. Here, we report a novel chiral zinc catalyst that can be isolated in 97 % yield from commercial sources, and that produces polycarbonates selectively from neat cyclohexene oxide under 1 bar of CO2 pressure at temperatures above 50 °C. At 80 °C reaction temperature, TONs of 1684 and initial TOFs up to 149 h−1 were measured, producing an isotactic‐enriched polycarbonate with a probability Pm of 65 % for the formation of a meso diad. Insight into the dinuclear nature of the active species and the copolymerization progress has been gained from structural and spectroscopic studies.
Dynamic Optimization of the PyNP/PNP Phosphorolytic Enzymatic Process Using MOSAICmodeling
Authors: Wilms Terrance , Rischawy Daniel Federico , Barz Tilman , Esche Erik , Repke Jens‐Uwe , Wagner Anke , Neubauer Peter , Cruz Bournazou Mariano Nicolas
Published: October 2017

Pyrimidine and purine nucleoside phosphorylases catalyze the reversible phosphorolytic cleavage and formation of the glycosidic bond of purine and pyrimidine nucleosides, respectively, and are thus, key catalysts for the synthesis of new compounds. The selection of the best combination of enzyme and reaction conditions is not trivial, as each of the two enzymes can perform the reaction in two directions and thus, also competes with the other one for the reaction intermediates. A generic approach to the solution of this problem based on the formulation of a mixed integer dynamic optimization program using MOSAICmodeling is presented.
IChem: A Versatile Toolkit for Detecting, Comparing, and Predicting Protein–Ligand Interactions
Authors: Da Silva Franck , Desaphy Jeremy , Rognan Didier
Published: October 2017

Structure‐based ligand design requires an exact description of the topology of molecular entities under scrutiny. IChem is a software package that reflects the many contributions of our research group in this area over the last decade. It facilitates and automates many tasks (e.g., ligand/cofactor atom typing, identification of key water molecules) usually left to the modeler's choice. It therefore permits the detection of molecular interactions between two molecules in a very precise and flexible manner. Moreover, IChem enables the conversion of intricate three‐dimensional (3D) molecular objects into simple representations (fingerprints, graphs) that facilitate knowledge acquisition at very high throughput. The toolkit is an ideal companion for setting up and performing many structure‐based design computations.
Distinct projection targets define subpopulations of mouse brainstem vagal neurons that express the autism‐associated MET receptor tyrosine kinase
Authors: Kamitakahara Anna , Wu Hsiao‐Huei , Levitt Pat
Published: October 2017

Detailed anatomical tracing and mapping of the viscerotopic organization of the vagal motor nuclei has provided insight into autonomic function in health and disease. To further define specific cellular identities, we paired information based on visceral connectivity with a cell‐type specific marker of a subpopulation of neurons in the dorsal motor nucleus of the vagus (DMV) and nucleus ambiguus (nAmb) that express the autism‐associated MET receptor tyrosine kinase. As gastrointestinal disturbances are common in children with autism spectrum disorder (ASD), we sought to define the relationship between MET‐expressing (MET+) neurons in the DMV and nAmb, and the gastrointestinal tract. Using wholemount tissue staining and clearing, or retrograde tracing in a METEGFP transgenic mouse, we identify three novel subpopulations of EGFP+ vagal brainstem neurons: (a) EGFP+ neurons in the nAmb projecting to the esophagus or laryngeal muscles, (b) EGFP+ neurons in the medial DMV projecting to the stomach, and (b) EGFP+ neurons in the lateral DMV projecting to the cecum and/or proximal colon. Expression of the MET ligand, hepatocyte growth factor (HGF), by tissues innervated by vagal motor neurons during fetal development reveal potential sites of HGF‐MET interaction. Furthermore, similar cellular expression patterns of MET in the brainstem of both the mouse and nonhuman primate suggests that MET expression at these sites is evolutionarily conserved. Together, the data suggest that MET+ neurons in the brainstem vagal motor nuclei are anatomically positioned to regulate distinct portions of the gastrointestinal tract, with implications for the pathophysiology of gastrointestinal comorbidities of ASD.
The role of individual colour preferences in consumer purchase decisions
Authors: Yu Luwen , Westland Stephen , Li Zhenhong , Pan Qianqian , Shin Meong Jin , Won Seahwa
Published: October 2017

The purpose of this study is to test whether consumers' personal colour preferences (in an abstract sense rather than for a particular product) affect their intended product purchase decisions if they are given various colour choices. This work employs two experiments with visual components to investigate which colour a participant would choose if asked to select a product to purchase when there is a range of colours available. Two experiments were also designed to elicit a response about which colour each participant prefers (in an abstract sense). The study finds that personal colour preferences affect intended product‐colour purchase decisions but that the extent of this varies from one product category to the next. Further analysis reveals that personal colour preferences are secondary to factors such as colour functionality and colour performance. This work presents new experimental data about the role of colour in product and product packaging on intended consumer purchase decisions. A conceptual framework, supported by the experimental findings, are understanding the relationship between individual colour preferences and product‐choice colours, and more functional aspects of colour itself (such as the effect of colour on product's performance or functionality).
Identification and formalization of knowledge for coloring qualitative geospatial data
Authors: Wu Mingguang , Chen Taisheng , Lv Guonian , Chen Menglin , Wang Hong , Sun Haoyu
Published: October 2017

Creating a satisfying qualitative color scheme from scratch may be difficult for novice mapmakers and experts. A probability‐based method is proposed to identify knowledge regarding qualitative color selection from readily available color schemes and formalize the discovered knowledge to assist in color creation. An unsupervised method to extract the general trends of color selection is presented, and the issue of qualitative color selection is translated into a multi‐constraint optimization problem. A feasible solution for achieving the global optimum is then provided. A probability‐based method is also proposed to match abstract color values with specific mapping features. This proposed approach is evaluated in a case study. The results of the case study suggest that the proposed method allows users to create qualitative color schemes more efficiently and confidently.
Impact of the Long‐Range Electronic Effect of a Fluorous Ponytail on Metal Coordination during Solvent Extraction
Authors: Braibant Bertrand , Le Goff Xavier , Bourgeois Damien , Meyer Daniel
Published: October 2017

With the need for a precise description of the long‐range electronic effects of a perfloroalkyl chain (F‐ponytail) grafted onto metal chelators, we studied in detail the effect of a spacer inserted between the polar complexing head and the F‐ponytail, in relation to the metal coordination ability of the resulting molecules. The prepared molecules were then applied for the extraction of various metals from an aqueous phase into an organic phase, and the optimum spacer length could be estimated to be between three and four methylene units, according to the extraction conditions. The study also revealed the difficulty of modeling and anticipating the tiny energy differences involved in the extraction process and the importance in peculiar cases to go beyond only these studied inductive effects to understand better the factors that govern the stabilization of a metallic cation in a complex fluorous phase.
Application of 3D Mass Spectrometry Imaging to TKIs
Authors: Morosi Lavinia , Giordano Silvia , Falcetta Francesca , Frapolli Roberta , Licandro Simonetta A. , Matteo Cristina , Zucchetti Massimo , Ubezio Paolo , Erba Eugenio , Visentin Sonja , D'Incalci Maurizio , Davoli Enrico
Published: October 2017

Mass spectrometry imaging (MSI) allows visualization of endogenous and exogenous compound in tissue sections based on its molecular mass. The 3D reconstruction by MSI provides a more informative description of the tumor drug distribution compared to the high‐performance liquid chromatography method, highlighting the heterogeneity of intratumor drug concentration. This additional information can be important in understanding chemoresistance to target agents. Here, we present the 3D visualization of the tyrosine kinase inhibitor (TKI), imatinib, in a xenograft model of resistant malignant pleural mesothelioma.
Explaining ecosystem multifunction with evolutionary models
Authors: Cadotte Marc W. , Livingstone Stuart W. , Yasui Simone‐Louise E. , Dinnage Russell , Li Jin‐tian , Marushia Robin , Santangelo James , Shu Wensheng
Published: October 2017

Ecosystem function is the outcome of species interactions, traits, and niche overlap – all of which are influenced by evolution. However, it is not well understood how the tempo and mode of niche evolution can influence ecosystem function. In evolutionary models where either species differences accumulate through random drift in a single trait or species differences accumulate through divergent selection among close relatives, we should expect that ecosystem function is strongly related to diversity. However, when strong selection causes species to converge on specific niches or when novel traits that directly affect function evolve in some clades but not others, the relationship between diversity and ecosystem function might not be very strong. We test these ideas using a field experiment that established plant mixtures with differing phylogenetic diversities and we measured ten different community functions. We show that some functions were strongly predicted by species richness and mean pairwise phylogenetic distance (MPD, a measure of phylogenetic diversity), including biomass production and the reduction of herbivore and pathogen damage in polyculture, while other functions had weaker (litter production and structural complexity) or nonsignificant relationships (e.g., flower production and arthropod abundance) with MPD and richness. However, these divergent results can be explained by different models of niche evolution. These results show that diversity‐ecosystem function relationships are the product of evolution, but that the nature of how evolution influences ecosystem function is complex.
High validity of cardiomyopathy diagnoses in western Sweden (1989–2009)
Authors: Basic Carmen , Rosengren Annika , Lindström Sandra , Schaufelberger Maria
Published: October 2017

Aim

Hospital discharges with a diagnosis of cardiomyopathy have more than doubled in Sweden since 1987. We validated the cardiomyopathy diagnoses over this time period to investigate that the increase was real and not a result of improved recognition of the diagnosis and better diagnostic methods.

Methods and results

Every fifth year from 1989 to 2009, records for all patients with a cardiomyopathy diagnosis were identified by searching the local registers in three hospitals in Västra Götaland, Sweden. The diagnoses were validated according to criteria defined by the European Society of Cardiology from 2008. The population comprised 611 cases with cardiomyopathy diagnoses [mean age 58.9 (SD 15.5) years, 68.2% male], divided into three major groups: dilated, hypertrophic, and other cardiomyopathies. Hypertrophic cardiomyopathy and hypertrophic obstructive cardiomyopathy were analysed as a group. Cardiomyopathies for which there were few cases, such as restrictive, arrhythmogenic right ventricular, left ventricular non‐compaction, takotsubo, and peripartum cardiomyopathies, were analysed together and defined as ‘other cardiomyopathies’. Relevant co‐morbidities were registered. The use of echocardiography was 99.7%, of which 94.6% was complete echocardiography reports. The accuracy rates of the diagnoses dilated cardiomyopathy, hypertrophic cardiomyopathy, and other cardiomyopathies were 85.5%, 87.5%, and 100%, respectively, with no differences between the three hospitals or years studied; nor did the prevalence of co‐morbidities differ.

Conclusions

The accuracy rate of the cardiomyopathy diagnoses from in‐hospital records from >600 patients in western Sweden during a 20 year period was 86.6%, with no significant trend over time, strengthening epidemiological findings that this is likely due to an actual increase in cardiomyopathy diagnoses rather than changes in coding practices. The use of echocardiography was high, and there was no significant difference in co‐morbidities during the study period. The accuracy rate of the cardiomyopathy diagnoses during the 20 year period was high. The use of diagnostic tools did not increase under the study period, and once cardiomyopathy diagnoses were suspected, echocardiography was performed in almost all cases. In this study, the occurrence of cardiomyopathy was increasing over time without significant increase of co‐morbidity, supporting that an actual increase of cardiomyopathy has occurred.
In Situ Generation and Immobilization of an Activated Rh Complex Catalyst in a Metal–Organic Framework for Hydrogenation at Low H2 Pressure
Authors: Takashima Yohei , Fukuhara Yoshimasa , Sato Yasushi , Tsuruoka Takaaki , Akamatsu Kensuke
Published: October 2017

Hydrogenation reactions under low‐pressure H2 atmosphere are highly relevant from the safety viewpoint, because H2 gas is highly flammable in air and explosions can be triggered by spark, heat, or sunlight. In this work, an Rh complex/MOF hybrid was synthesized and used as catalyst for the hydrogenation of alkene substrates. Thanks to the activation of the Rh complex catalyst during the immobilization process and the intrinsic gas‐condensation property of MOFs, the resulting composite showed much higher catalytic activity than the complex catalyst itself. Moreover, the composite can maintain its catalytic activity even at low H2 pressures that cannot support the reaction with the complex catalyst alone. Furthermore, in contrast to the complex catalyst, the composite maintained its catalytic activity even without solvent, and thus provides an environmentally friendly approach to catalysis.
Organocatalytic Asymmetric [4+2] Cycloaddition of 1‐Acetylcyclopentene and 1‐Acetylcyclohexene for the Synthesis of Fused Carbocycles
Authors: Nath Utpal , Pan Subhas Chandra
Published: October 2017

The first organocatalytic asymmetric [4+2]‐cycloaddition reaction of 1‐acetylcyclopentenes and 1‐acetylcyclohexenes was developed. Enones having cyano groups were used as the dienophiles in this method. The reaction provides a useful practical route to the synthesis of bicyclic fused carbocycles having four contiguous stereocenters.
A Computational Study of Anionic Alkoxide–Allene and Amide–Allene Cyclizations
Authors: Cumine Florimond , Young Allan , Reissig Hans‐Ulrich , Tuttle Tell , Murphy John A.
Published: October 2017

Computational studies have been performed on potassium alkoxide‐allenes, as well as potassium and lithium amido‐allenes to probe the mechanism of their cyclizations to dihydrofurans and to 2,5‐dihydropyrroles. A long‐standing proposal envisaged electron transfer from dimsyl anions (formed by deprotonation of the solvent DMSO) but this pathway shows an exceptionally high kinetic barrier, while direct 5‐endo‐trig cyclization of the alkoxides and amides is much more easily achievable. The energy profiles for 4‐exo‐trig cyclizations onto the allenes are also explored, and the preferred formation of the observed five‐membered products is rationalized.
Genotoxicity of airborne PM2.5 assessed by salmonella and comet assays in five cities of the Emilia‐Romagna (Italy) mutagenicity monitoring network
Authors: Bocchi Clara , Bazzini Cristina , Fontana Federica , Pinto Giancarlo , Cassoni Francesca
Published: October 2017

Airborne particulate matter (PM) has long been recognized as a potential health hazard and in 2013 was classified as carcinogenic to humans by the International Agency for Research on Cancer. In this study we evaluate and compare mutagenic and genotoxic potencies of PM2.5 collected in three seasons, from 2012 to 2015, in five Italian cities. Mutagenicity was evaluated through the Ames test on TA98 and TA100 strains and, for the measurement of PM clastogenicity, Comet assay was carried out on cultured human lung cells (A549). Organic matter, extracted from urban particulate matter, was also characterized for polycyclic aromatic hydrocarbons (PAHs) and their derivatives content. Samples collected in the colder seasons show the presence of both base pair substitution and frameshift mutagens, with enhanced mutagenic response in the absence of enzyme activation. The highest DNA damage detected with the Comet assay was induced by winter extracts, but different from Salmonella, the relative increase per cubic meter in comet tail for November samples was comparable to July ones. Comparing mutagenicity and genotoxicity with chemical concentrations we found that data from the Salmonella assay correlate with mass concentration and, to a lesser extent, with PAHs, but no association was found with their derivatives, whereas DNA damage correlate only with PAHs measured at one site. These findings demonstrate that to assess the mutagenicity and genotoxicity of complex mixtures it's necessary to use bioassays and that the chemical analysis of pollutants does not take into account the possible inhibitory or synergic effects of exposure. Environ. Mol. Mutagen. 58:719–729, 2017. © 2017 Wiley Periodicals, Inc.
Bayesian inference in time‐varying additive hazards models with applications to disease mapping
Authors: Chernoukhov A. , Hussein A. , Nkurunziza S. , Bandyopadhyay D.
Published: October 2017

Environmental health and disease mapping studies are often concerned with the evaluation of the combined effect of various sociodemographic and behavioral factors, and environmental exposures, on time‐to‐event outcomes of interest, such as death of individuals, organisms, or plants. In such studies, estimation of the hazard function is often of interest. In addition to the known explanatory variables, the hazard function may be subject to spatial/geographical variations, such that proximally located regions may experience hazards similar to those of regions that are distantly located. A popular approach for handling this type of spatially correlated time‐to‐event data is the Cox proportional hazards regression model with spatial frailties. However, the proportional hazards assumption poses a major practical challenge, as it entails that the effects of the various explanatory variables remain constant over time. This assumption is often unrealistic, for instance, in studies with long follow‐ups where the effects of some exposures on the hazard may vary drastically over time. Our goal in this paper is to offer a flexible semiparametric additive hazards model with spatial frailties. Our proposed model allows both the frailties and the regression coefficients to be time varying, thus relaxing the proportionality assumption. Our estimation framework is Bayesian, powered by carefully tailored posterior sampling strategies via Markov chain Monte Carlo techniques. We apply the model to a data set on prostate cancer survival from the U.S. state of Louisiana to illustrate its advantages.
Phenotype validation in electronic health records based genetic association studies
Authors: Wang Lu , Damrauer Scott M. , Zhang Hong , Zhang Alan X. , Xiao Rui , Moore Jason H. , Chen Jinbo
Published: October 2017

The linkage between electronic health records (EHRs) and genotype data makes it plausible to study the genetic susceptibility of a wide range of disease phenotypes. Despite that EHR‐derived phenotype data are subjected to misclassification, it has been shown useful for discovering susceptible genes, particularly in the setting of phenome‐wide association studies (PheWAS). It is essential to characterize discovered associations using gold standard phenotype data by chart review. In this work, we propose a genotype stratified case‐control sampling strategy to select subjects for phenotype validation. We develop a closed‐form maximum‐likelihood estimator for the odds ratio parameters and a score statistic for testing genetic association using the combined validated and error‐prone EHR‐derived phenotype data, and assess the extent of power improvement provided by this approach. Compared with case‐control sampling based only on EHR‐derived phenotype data, our genotype stratified strategy maintains nominal type I error rates, and result in higher power for detecting associations. It also corrects the bias in the odds ratio parameter estimates, and reduces the corresponding variance especially when the minor allele frequency is small.
Pathologic significance of a novel oncoprotein in thyroid cancer progression
Authors: Firek Anthony A. , Perez Mia C. , Gonda Amber , Lei Li , Munir Iqbal , Simental Alfred A. , Carr Frances E. , Becerra Benjamin J. , De Leon Marino , Khan Salma
Published: October 2017

Background

The incidence of thyroid cancer is increasing worldwide, and there is an emerging need to develop accurate tools for diagnosis. Fine needle aspiration biopsy has greatly improved evaluation of thyroid nodules, but challenges with indeterminate lesions remain in up to 25% of biopsies. Novel tissue biomarkers may assist in improved nodule characterization. Microcalcifications occurring in thyroid cancers suggest proteins involved in bone formation may play a role in thyroid carcinogenesis. We evaluated the expression of the known osteogenic protein, Enigma, in thyroid cancer as a candidate oncoprotein and role in carcinogenesis based on association with other known oncoproteins such as bone morphogenetic protein‐1 (BMP‐1).

Methods

The expression of both Enigma and BMP‐1 were evaluated by immunohistochemistry (IHC) in an equal number of benign (n = 120) and different histological subtypes of malignant (n = 120) human archival thyroid nodules with and without calcification. The colocalization of Enigma with BMP‐1 was evaluated by confocal microscopy using the BZ analyzer.

Results

Enigma was strongly expressed in thyroid cancer tissue with a higher immunoreactive score in advanced thyroid cancer compared to less advanced and benign nodules. Enigma was localized either in cytoplasm or nucleus depending on the histological subtypes. Higher expression of Enigma was associated with the tumor size and lymph node involvement. There was clear and strong colocalization signal of Enigma and that of BMP‐1. Expression of Enigma occurred without regard to calcification in cancer tissue.

Conclusion

Enigma may serve as an oncoprotein marker, identifying benign from malignant thyroid tissue on FNA. Enigma may have a role in carcinogenesis of thyroid cancer independent of tissue calcification, possibly in relation to interaction with BMP‐1.
Shortening gestational age at term and organisation of birth care in the Czech Republic
Authors: Štípková Martina
Published: October 2017

A trend of the shortening duration of pregnancies carried to term has been observed in several countries and represents a growing public health concern. This paper describes the trend in the Czech Republic and shows its relation to the changing demographic structure of mothers and the organisation of maternity care. Data from the birth register are used and supplemented with information about the capacity of maternity care (number of beds at maternity clinics, number of obstetricians and midwives). Logistic regression is used to estimate the odds of 37 to 39 vs 40+ completed weeks of gestation. The results show that the average gestational age at term decreased by 2.1 days between 2000 and 2013. The odds of 37 to 39 weeks of gestational duration increased, mainly due to the reduction in the number of beds at maternity clinics (adjusted odds ratio of 1.51). The effects of the number of health care staff members were weaker. The number of midwives positively influenced gestational duration, while the number of obstetricians had a negative effect. Maternal demographic structure cannot explain the trend. A likely explanation is the increased use of planned early term caesarean sections.
Analysis of snowpack dynamics during the spring melt season for a sub‐alpine site using point measurements and numerical modeling
Authors: Pleasants Mark S. , Kelleners Thijs J. , Ohara Noriaki
Published: October 2017

Snowpack dynamics through October 2014–June 2017 were described for a forested, sub‐alpine field site in southeastern Wyoming. Point measurements of wetness and density were combined with numerical modeling and continuous time series of snow depth, snow temperature, and snowpack outflow to identify 5 major classes of distinct snowpack conditions. Class (i) is characterized by no snowpack outflow and variable average snowpack temperature and density. Class (ii) is characterized by short durations of liquid water in the upper snowpack, snowpack outflow values of 0.0008–0.005 cm hr−1, an increase in snowpack temperature, and average snow density between 0.25–0.35 g cm−3. Class (iii) is characterized by a partially saturated wetness profile, snowpack outflow values of 0.005–0.25 cm hr−1, snowpack temperature near 0 °C, and average snow density between 0.25–0.40 g cm−3. Class (iv) is characterized by strong diurnal snowpack outflow pattern with values as high as 0.75 cm hr−1, stable snowpack temperature near 0 °C, and stable average snow density between 0.35–0.45 g cm−3. Class (v) occurs intermittently between Classes (ii)–(iv) and displays low snowpack outflow values between 0.0008–0.04 cm hr−1, a slight decrease in temperature relative to the preceding class, and similar densities to the preceding class. Numerical modeling of snowpack properties with SNOWPACK using both the Storage Threshold scheme and Richards' equation was used to quantify the effect of snowpack capillarity on predictions of snowpack outflow and other snowpack properties. Results indicate that both simulations are able to predict snow depth, snow temperature, and snow density reasonably well with little difference between the 2 water transport schemes. Richards' equation more accurately simulates the timing of snowpack outflow over the Storage Threshold scheme, especially early in the melt season and at diurnal timescales.