bluuebunny/crossref_metadata_2025 huggingface dataset:
Functionalization of halloysite nanotube surfaces via controlled living radical polymerization: covalent immobilization of penicillin for a bioactive interface
Authors: Nguyen Trinh D , Vo Sang T , Islam Md R , Lim Kwon T , Vo Dai‐Viet N , Bach Long G
Published: November 2018

Background

Surface functionalization of nanomaterials has attracted much attention in the fields of chemistry, materials science, biology, and medicine because the surface chemistry and topology of nanomaterials has dramatic effects on the resulting material properties. Various strategies have been employed to modify the surface properties of substrates, including the immobilization of polymer brushes on a solid substrate using ‘living’/controlled radical polymerization methods.

Results

A halloysite nanotubes (HNTs) surface was fabricated through the growth of poly(ethylene glycol)‐based brushes (PPEGMA) via a living radical polymerization method followed by coupling of a model antibiotic, penicillin (PE). Fourier transform infrared (FTIR) spectroscopy confirmed all three segments of the nanohybrids were covalently attached. Successful covalent functionalization was also confirmed using X‐ray photoelectron spectroscopy (XPS) and energy dispersive X‐ray (EDX) spectrometry. The field emission scanning electron microscopy (FE‐SEM) images of the nanohybrids showed that a soft layer of polymer was immobilized on the nanotubes. Bioassay studies revealed that the covalently attached penicillin retained its antibacterial properties againstE. coliandS. aureus.

Conclusion

A synthetic strategy for the functionalization of HNTs PPEGMA via surface‐initiated atom transfer radical polymerization (SI‐ATRP) has been successfully developed to permit covalent immobilization of antibiotics. First, PPEGMA‐grafted HNTs (HNTs‐g‐PPEGMA) were synthesized via a controlled SI‐ATRP of PPEGMA, followed by silanization using (3‐aminopropyl)trimethoxysilane to afford amine group‐containing nanohybrids (HNTs‐g‐PPEGMA‐NH2). Subsequently, PE was anchored to the surface of HNTs‐g‐PPEGMA‐NH2via carbodiimide chemistry. The high bactericidal efficiency of the synthetic hybrid towards gram‐positiveS. aureusand gram‐negativeE. coliwas demonstrated. Thus, this biofunctionalization strategy holds great potential for applications in the field of bio‐nanotechnology. © 2018 Society of Chemical Industry
An ultrasound‐responsive dual‐modal US/T1‐MRI contrast agent for potential diagnosis of prostate cancer
Authors: Yoon Young Il , Ha Shin‐Woo , Lee Hak Jong
Published: November 2018

Background

Interest in an ultrasound‐mediated delivery system for effective T1‐MRI of prostate cancer without adverse effects has steadily increased.

Purpose

To develop an ultrasound‐responsive dual‐modal ultrasound (US)/T1‐MRI contrast agent for efficient diagnosis of prostate cancer cells overexpressing prostate‐specific membrane antigen (PSMA) and assess their potential.

Study Type

In vitro.

Subjects

Two prostate cancer cell lines.

Field Strength/Sequence

Each study group underwent 3.0T MRI under a TR 400 msec, TE 10 msec, a 240 × 240 matrix, a flip angle 90°, a slice thickness 3 mm, NSA with 4, bandwidth 115 Hz/pixel, and an FOV of 120 × 120 mm.

Assessment

Microscopes, quantitative and qualitative analyzing instruments, and clinical devices were used for assessing this novel contrast agent and its diagnosis effects.

Statistical Tests

We used linear regression analyses to determine the longitudinal relaxivity (r1) values of our US/T1‐MRI contrast agent and gadobutrol.

Results

Microbubble+Fe3+melanin nanoparticle+peptides (MB+Fe3+MNPPs) had a good US contrast effect, like a commercial US agent. The differences of US intensities between them was below 5%. The r1 values of MB+Fe3+MNPPs and gadobutrol were 4.5 and 3.7 s‐1/mM, respectively. More than hundreds of Fe3+MNPPs were located in prostate cancer cells treated with MB+Fe3+MNPPs and US stimulus, but the number of Fe3+MNPPs was below dozens in the other prostate cancer cells expressing less PSMA. The former cells with MB+Fe3+MNPPs and US stimulus only showed the highest T1‐MRI signal because of synergy effects of the peptides targeting the cells and US stimulus for delivery of Fe3+MNPPs to the cells. No cytotoxicity of MB+Fe3+MNPPs was confirmed by using a WST assay. Viability of the cells with the complexes was above 90%.

Data Conclusion

We synthesized MB+Fe3+MNPPs as a potential US/T1‐MRI contrast agent. This complex was applicable for diagnosing desired prostate cancer cells.

Level of Evidence: 1

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2018;48:1610–1616
Biomechanical evaluation of tendon regeneration with adipose‐derived stem cell
Authors: de Lima Santos Alex , Silva Camila Gonzaga da , de Sá Barretto Leticia Siqueira , Franciozi Carlos Eduardo da Silveira , Tamaoki Marcel Jun Sugawara , de Almeida Fernando Gonçalves , Faloppa Flavio
Published: November 2018

The use of Adipose‐Derived Stem Cells (ADSC) has been presented as a new alternative for tendon reconstruction. Have been admitted that ADSCs are related to better outcomes when used in tendon healing. This research was designed to apply the potential of ADSCs in tendon healing. Flexor digitorum superficialis tendon lesion was performed on both legs of eleven New Zealand rabbits and them, at the same time, treated as follows: Suture alone (Group III − Suture, n:10), suture associated with ADSC (Group IV − Suture + ADSC, n:10) or without suture (Group II − SHAN, n:2). At four weeks after the tendon surgery, the animal was euthanized, and the tendon evaluated (biomechanically and macroscopically). We used 5 additional New Zealand rabbits in the control group “Group I − Control, n:10”. In the macroscopic evaluation, the group with ADSC presented a more homogeneous gross morphology compared with the group III. Biomechanical testing showed a lower ultimate tensile load, stiffness and a higher cross‐sectional area in the group III and IV compared with the control group. The group with ADSC showed a greater ultimate tensile load, a larger cross‐sectional area and bigger deformation at the ultimate tensile load when compared to the group without ADSC. In general terms, the use of ADSCs in tendon healing have biomechanical advantages compared to the non‐use of ADSCs at 4 weeks after surgery. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1281–1286, 2019.
Predictors of fracture healing in patients with recalcitrant nonunions treated with autologous culture expanded bone marrow‐derived mesenchymal stromal cells
Authors: Bhattacharjee Atanu , Kuiper Jan H. , Roberts Sally , Harrison Paul E. , Cassar‐Pullicino Victor N. , Tins Bernhard , Bajada Stefan , Richardson James B.
Published: November 2018

The study reports the prospective outcome of treating severe recalcitrant fracture nonunion in patients with autologous bone marrow‐derived mesenchymal stromal cells (BMSC) from 2003 to 2010 and analyze predictors of union. Autologous BMSC were culture expanded and inserted at nonunion site with or without carriers in addition to surgical stabilization of the fracture. Radiological union was ascertained by musculoskeletal radiologists on plain radiographs and/or CT scans. A logistic regression analysis was performed with cell‐expansion parameters (cell numbers, cell doubling time) and known clinical factors (e.g., smoking and diabetes) as independent variables and fracture union as the dependent variable to identify the factors that influence bony healing. An Eq5D index score assessed the effect of treatment on general quality of health. A total of 35 patients (mean age 51+/−13 years) with established nonunion (median 2.9 years, 1–33) and, at least one failed nonunion surgery (median 4,1–14) received treatment. Fracture union was achieved in 21 patients (60%; 95%CI 44–75) at 2.6 years. Multiple penalized logistic regression revealed faster cell doubling time (p = 0.07), absence of diabetes (p = 0.003), less previous surgeries (p = 0.008), and lower age at cell implantation (p = 0.02) were significant predictors for fracture union. A significant increase in Eq5D index (p = 0.01) was noted with a mean rise of the score by 0.34 units (95%CI 0.11–0.58) at 1 year following the study. In summary, the study revealed cell doubling time as a novel in vitro parameter in conjunction with age, multiple surgeries, and diabetes as being significant predictors of the fracture union. © 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. J Orthop Res 37:1303–1309, 2019.
A Facile Route to Bio‐Inspired Supramolecular Oligo(Ethylene Glycol) Catecholates
Authors: Shannon Alice , Manolakis Ioannis
Published: November 2018

A particularly facile synthetic route to mussel‐inspired oligo(ethylene glycol) catecholates is described, yielding high purity materials with minimal purification. The oligocatecholates show remarkable thermal and rheological properties for their actual chain length, suggesting the operation of non‐covalent interactions between their l‐DOPA‐bearing chain ends. This end‐group effect is more pronounced in the shorter oligomers (M
n of ethylene glycol chain of 200 and 400 Da), where the end‐group density is higher. Various surfaces (glass, stainless steel) are modified with the oligocatecholates, using a dip‐coating approach from dilute aqueous solutions. Water contact angle measurements and X‐ray photoelectron spectroscopy confirm the presence of a hydrophilic surface coating layer. The potential of these materials for application as antifouling coatings and viscosity modifiers is highlighted.
Advances in Light‐Emitting Dendrimers
Authors: Abd‐El‐Aziz Alaa S. , Abdelghani Amani A. , Wagner Brian D. , Bissessur Rabin
Published: November 2018

The design of dendrimers with various chromophores has attracted significant attention in light of the dual effect of the luminescence of the chromophores and the morphology of the synthesized dendrimers. Recent developments in this field stem from their wide potential applications, including organic light‐emitting diodes, photonic switches and upconversion lasers, as well as sensors and electronic devices. The focus of this comprehensive review is on the design and properties of various classes of light‐harvesting dendrimeric materials.
Design of a planar slot tag antennas with circular polarization for ultra‐high frequency radio frequency identification applications
Authors: Ben Abdallah Essia , Egels Matthieu , Bergeret Emmanuel , Benzaim Oussama , Pannier Philippe
Published: November 2018

Slot radio frequency identification (RFID) Tag antennas designed for ultra‐high frequency (UHF) band are presented. Two orthogonal slots are used to achieve circular polarization (CP). By selecting an appropriate length of feed‐lines, the input impedance of the tag antenna can be controlled. Experimental results show a good reading range between 9 m and 10 m. A wide band CP band was measured. The design procedure for the proposed antennas are described and the performances are presented and discussed.
Compact microstrip lowpass‐bandpass diplexer using radial stubs
Authors: Perez‐Wences Cain , Loo‐Yau Jose R. , Lavandera‐Hernandez Ismary , Moreno Pablo , Reynoso‐Hernandez Apolinar J. , Aguilar‐Lobo Lina M.
Published: November 2018

In this work, a compact microstrip lowpass‐bandpass diplexer using radial stubs (RSs) is proposed. By controlling the input impedance of the RS resonators, it is possible to obtain a selective lowpass filter (LPF) and a narrow bandpass filter (BPF) with a fractional bandwidth of 5%, without increasing the insertion losses (ILs) of both filters. The design methodology is explained in details and verified through the design of a diplexer achieving very low IL, 0.15 dB for the LPF and 1.2 dB for the BPF. Moreover, the isolation between the ports is 25 dB making the proposed diplexer useful for designing mixer circuits. Experimental results exhibit high correlation with EM simulation data validating the proposed methodology.
Influence of background suppression and retrospective realignment on free‐breathing renal perfusion measurement using pseudo‐continuous ASL
Authors: Taso Manuel , Guidon Arnaud , Alsop David C.
Published: November 2018

Purpose

To assess the influence of background suppression and retrospective realignment on physiological noise and image quality in free‐breathing renal pseudo‐continuous arterial spin labeling (pCASL).

Methods

Ten subjects were scanned at 3T with a pCASL prepared single‐slice coronal acquisition through the kidneys under free breathing. Multiple acquisitions were performed with various levels of residual background signal based on optimization of pulse timings to achieve specific background suppression levels (<2%, <5%, <10%, <20%). A retrospective non‐rigid motion‐correction strategy was also implemented.

Results

Decreasing level of residual background signal was associated with higher temporal SNR. The retrospective motion‐correction provided an additional but not statistically significant improvement in tSNR. The highest image quality was obtained with the lowest level of residual background signal accompanied by the retrospective motion‐correction, although no significant difference in quantitative renal blood‐flow could be observed.

Conclusions

Renal perfusion measurement with ASL under free breathing is feasible and robust against physiological noise when using strong background suppression strategies. Finally, retrospective motion‐correction further improves image quality but cannot replace background suppression.
3D self‐gated cardiac cine imaging at 3 Tesla using stack‐of‐stars bSSFP with tiny golden angles and compressed sensing
Authors: Zhang Xiaoyong , Xie Guoxi , Lu Na , Zhu Yanchun , Wei Zijun , Su Shi , Shi Caiyun , Yan Fei , Liu Xin , Qiu Bensheng , Fan Zhaoyang
Published: November 2018

Purpose

To develop and evaluate an accelerated 3D self‐gated cardiac cine imaging technique at 3 Tesla without the use of external electrocardiogram triggering or respiratory gating.

Methods

A 3D stack‐of‐stars balanced steady‐state free precession sequence with a tiny golden angle sampling scheme was developed to reduced eddy current effect‐related artefacts at 3 Tesla. Respiratory and cardiac motion were derived from a central 5‐point self‐gating signal extraction approach. The data acquired around the end‐expiration phases were then sorted into individual cardiac bins and used for reconstruction with compressed sensing. To evaluate the performance of the proposed method, image quality (1: the best; 4: the worst) was quantitatively compared using both the proposed method and the conventional 3D golden‐angle self‐gated method. Linear regression and Bland‐Altman analysis were used to assess the functional measurements agreement between the proposed method and the routine 2D breath‐hold multi‐slice technique.

Results

Compared to the conventional 3D golden‐angle self‐gated method, the proposed method yielded images with much less streaking artifact and higher myocardium edge sharpness (0.50 ± 0.06 vs. 0.45 ± 0.05, P = 0.004). The proposed method provided an inferior image quality score to the routine 2D technique (2.13 ± 0.35 vs. 1.38 ± 0.52, P = 0.063) but a superior one to the conventional self‐gated method (2.13 ± 0.35 vs. 3.13 ± 0.64, P = 0.031). Left ventricular functional measurements between the proposed method and routine 2D technique were all well in agreement.

Conclusion

This study presents a novel self‐gating approach to realize rapid 3D cardiac cine imaging at 3 Tesla.
Probing carbohydrate metabolism using hyperpolarized 13C‐labeled molecules
Authors: Singh Jaspal , Suh Eul Hyun , Sharma Gaurav , Khemtong Chalermchai , Sherry A. Dean , Kovacs Zoltan
Published: November 2018

Glycolysis is a fundamental metabolic process in all organisms. Anomalies in glucose metabolism are linked to various pathological conditions. In particular, elevated aerobic glycolysis is a characteristic feature of rapidly growing cells. Glycolysis and the closely related pentose phosphate pathway can be monitored in real time by hyperpolarized 13C‐labeled metabolic substrates such as 13C‐enriched, deuterated D‐glucose derivatives, [2‐13C]‐D‐fructose, [2‐13C] dihydroxyacetone, [1‐13C]‐D‐glycerate, [1‐13C]‐D‐glucono‐δ‐lactone and [1‐13C] pyruvate in healthy and diseased tissues. Elevated glycolysis in tumors (the Warburg effect) was also successfully imaged using hyperpolarized [U‐13C6, U‐2H7]‐D‐glucose, while the size of the preexisting lactate pool can be measured by 13C MRS and/or MRI with hyperpolarized [1‐13C]pyruvate. This review summarizes the application of various hyperpolarized 13C‐labeled metabolites to the real‐time monitoring of glycolysis and related metabolic processes in normal and diseased tissues.
Association of Maternal Prepregnancy Weight with Offspring Adiposity Throughout Adulthood over 37 Years of Follow‐up
Authors: Schoppa Isabelle , Lyass Asya , Heard‐Costa Nancy , de Ferranti Sarah D. , Fox Caroline , Gillman Matthew W. , D’Agostino Ralph , Levy Daniel , Mendelson Michael M.
Published: November 2018

Objective

This study aimed to determine the relation of maternal prepregnancy weight with offspring BMI across adulthood from almost 40 years of follow‐up.

Methods

BMI was measured in Framingham Heart Study Offspring cohort participants between 1971 and 2008. The association of maternal prepregnancy weight category (ascertained via direct measure and questionnaire) with serial offspring BMI, overweight, obesity, and change in BMI over time was tested, adjusted for age, sex, and a BMI genetic risk score; secondary models additionally adjusted for physical activity, dietary factors, smoking, education, and familial relatedness.

Results

Among 863 participants at initial assessment (83 exposed and 780 controls), mean (SD) age was 33 (10) years, 53% were female, and mean BMI was 24.5 (4.1) kg/m2. Exposed offspring BMI was higher at every examination cycle, ranging from 1.5 (0.5) to 3.0 (0.5) kg/m2 (P < 0.001), with larger differences at later assessments. The rate of increase in offspring BMI over time was higher in exposed offspring before the age of 50 years (β [SE] = 0.07 [0.02] kg/m2 per year; P = 0.004) but not after the age of 50 years (−0.05 [0.04] kg/m2 per year; P = 0.2).

Conclusions

Maternal prepregnancy weight is associated with greater offspring BMI throughout adulthood, with more rapid weight acceleration in early and midadulthood.
Factors Controlling the Diels–Alder Reactivity of Hetero‐1,3‐Butadienes
Authors: Yu Song , de Bruijn Hans M. , Svatunek Dennis , Hamlin Trevor A. , Bickelhaupt F. Matthias
Published: November 2018

We have quantum chemically explored the Diels–Alder reactivities of a systematic series of hetero‐1,3‐butadienes with ethylene by using density functional theory at the BP86/TZ2P level. Activation strain analyses provided physical insight into the factors controlling the relative cycloaddition reactivity of aza‐ and oxa‐1,3‐butadienes. We find that dienes with a terminal heteroatom, such as 2‐propen‐1‐imine (NCCC) or acrolein (OCCC), are less reactive than the archetypal 1,3‐butadiene (CCCC), primarily owing to weaker orbital interactions between the more electronegative heteroatoms with ethylene. Thus, the addition of a second heteroatom at the other terminal position (NCCN and OCCO) further reduces the reactivity. However, the introduction of a nitrogen atom in the backbone (CNCC) leads to enhanced reactivity, owing to less Pauli repulsion resulting from polarization of the diene HOMO in CNCC towards the nitrogen atom and away from the terminal carbon atom. The Diels–Alder reactions of ethenyl‐diazene (NNCC) and 1,3‐diaza‐butadiene (NCNC), which contain heteroatoms at both the terminal and backbone positions, are much more reactive due to less activation strain compared to CCCC.
DYNAMIC SCORING OF TAX REFORMS IN THE EUROPEAN UNION
Authors: Barrios Salvador , Dolls Mathias , Maftei Anamaria , Peichl Andreas , Riscado Sara , Varga Janos , Wittneben Christian
Published: November 2018

In this paper, we present the first dynamic scoring exercise linking a microsimulation and a dynamic general equilibrium model for Europe. We illustrate our novel methodology analyzing hypothetical reforms of the social insurance contributions system in Belgium. Our approach takes into account the feedback effects resulting from adjustments and behavioral responses in the labor market and the economy‐wide reaction to the tax policy changes essential for a comprehensive evaluation of the reforms. We find that the self‐financing effect of a reduction in employers’ social insurance contribution is substantially larger than that of a comparable reduction in employees’ social insurance contributions.
The association between maternal methylenetetrahydrofolate reductase C677T and A1298C polymorphism and birth defects and adverse pregnancy outcomes
Authors: Zhang Yuan , He Xia , Xiong Xuan , Chuan Junlan , Zhong Lei , Chen Guo , Yu Dongke
Published: November 2018

Published studies indicate the MTHFR C677T and A1298C polymorphisms are associated with abnormal homocysteine levels, which may cause various pregnancy complications and birth defects. However, the results obtained from different studies have been inconsistent. Therefore, this meta‐analysis explores the association between MTHFR polymorphisms and birth defects and adverse pregnancy outcomes. The PubMed, ScienceDirect, Embase, and China Biology Medicine literature databases and ClinicalTrials were searched. Analyses of public bias, meta‐regression, subgroups, and sensitivity were used to ensure the robustness of our results. MTHFR C677T was significantly associated with recurrent pregnancy loss in developing countries (odds ratio [OR], 1.34; 95% confidence interval [CI], 1.20‐1.50) but not in developed countries (OR, 0.87; 95% CI, 0.68‐1.11). No significant relationship was found between MTHFR A1298C and recurrent pregnancy loss (OR, 1.04; 95% CI, 0.93‐1.18). MTHFR C677T and A1298C were not associated with preeclampsia (OR, 1.06; 95% CI, 0.97‐1.16 and OR, 1.16; 95% CI, 0.97‐1.39, respectively), and C677T was not associated with placental abruption (OR, 1.03; 95% CI, 0.87‐1.21), intrauterine growth retardation (OR, 1.02; 95% CI, 0.90‐1.15), or congenital heart disease (OR, 1.05; 95% CI, 0.89‐1.25). MTHFR C677T, but not A1298C, was associated with neural tube defects (OR, 1.24; 95% CI, 1.08‐1.42) and Down syndrome (OR, 1.65; 95% CI, 1.39‐1.95).

Conclusion

Although MTHFR C677T and A1298C are significantly associated with some types of congenital defects and adverse pregnancy outcomes, the impact of these polymorphisms is moderate.
Photopolymerization synthesis of polyacrylic acid dispersant with methoxysilicon end groups and its application in a nano‐SiO2 aqueous system
Authors: Yang Bing , Zhou Yu , Yu Wenjie , Zhang Song , Chen Hongxiang , Ye Ju
Published: November 2018

In order to improve the dispersity and stability of the nano‐SiO2 aqueous system with high solid content, a kind of polyacrylic acid dispersant with methoxysilicon end groups (KH590‐PAA) was synthesized by photopolymerization of acrylic acid (AA) initiated with (3‐mercaptopropyl)trimethoxysilane (KH590). After adding KH590‐PAA into the nano‐SiO2 aqueous dispersion system (20 wt% solid content), the viscosity and the curing time of the system were measured with a rotational viscometer and the inverted bottle method. Moreover, the dispersion mechanism of KH590‐PAA for the nano‐SiO2 aqueous system was researched by measuring the adsorption capacity, the particle size and the zeta potential of the nanoparticles with a conductivity meter, dynamic light scattering, SEM and TEM, respectively. The results showed that the methoxysilicon groups in KH590‐PAA could react with hydroxyl groups on the surface of nano‐SiO2 in the process of stirring, which enhanced the adsorption capacity of the dispersant and then increased the surface charge of the particles. Therefore, electrostatic repulsion and steric hindrance effects between the SiO2 nanoparticles could be further enhanced by adding the KH590‐PAA dispersant, and then the nano‐SiO2 aqueous system exhibited better dispersity and stability. Besides, the dispersion properties of SiO2 nanoparticles in water were closely related to the addition amount and the molecular weight of the KH590‐PAA dispersant. © 2018 Society of Chemical Industry
Effect of PLGA block molecular weight on gelling temperature of PLGA‐PEG‐PLGA thermoresponsive copolymers
Authors: Steinman Noam Y. , Haim‐Zada Moran , Goldstein Isaac A. , Goldberg Ayelet H. , Haber Tom , Berlin Jacob M. , Domb Abraham J.
Published: November 2018

Thermoresponsive, biodegradable polymeric hydrogel networks are used widely in medicinal applications. Poly(d,l‐lactic acid‐co‐glycolic acid)‐b‐poly(ethylene glycol)‐b‐poly(d,l‐lactic acid‐co‐glycolic acid) (PLGA‐PEG‐PLGA) triblock copolymers exhibit a sol–gel transition upon heating. The effect of PLGA block and PEG chain molecular weights (MWs) on the gelling temperature of polymer aqueous solution (20% w/w) is described. All polymer solutions convert into a hard gel within 2 °C of the gelling temperature. The release properties of the gels were displayed using paracetamol as a representative drug. A linear relation is described between the gelling temperature and PLGA block MW. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 35–39
Mechanical and electrical response variation of the polyurethane–tin oxide–carbon nanotube composite microfiber depending on the chemical solution
Authors: Cho Hyuk‐Joon , Jeong Sang‐Mi , Lim Taekyung , Ju Sanghyun
Published: November 2018

Toward the goal of smart sensor systems for wearable electronics, polymer microfiber‐based free‐standing sensors benefit from excellent flexibility, decent ductility, and easy wearability in comparison with thin‐film‐based sensing devices. Herein, we report a hydrophobic and conducting single‐strand microfiber‐based liquid‐phase chemical sensor consisting of polyurethane (PU), tin oxide (SnO2), and carbon nanotube (CNT) composites with applying a (1H,1H,2H,2H‐heptadecafluorodec‐1‐yl) phosphonic acid (HDF‐PA)‐based self‐assembled monolayer. The free‐standing HDF‐PA‐treated PU–SnO2–CNT composite microfiber showing selective filtering properties with the repellency of water and the penetration of an organic solvent is electrically and mechanically characterized. Finally, the single‐strand HDF‐PA‐treated PU–SnO2–CNT composite microfiber‐based chemical sensor, which shows excellent mechanical properties and aqueous stability, is demonstrated to detect the presence of a chemical in pure water or counterfeit gasoline in pure gasoline by observing mechanical changes, especially variations in the length and diameter of the fiber, and monitoring the electrical resistance change. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 495–502
Effects of Heat Exposure and Volumetric Compression on Poisson's Ratios, Young's Moduli, and Polymeric Composition During Thermo‐Mechanical Conversion of Auxetic Open Cell Polyurethane Foam
Authors: Duncan Olly , Clegg Francis , Essa Abdusalam , Bell Anthony M. T. , Foster Leon , Allen Tom , Alderson Andrew
Published: November 2018

The effects of thermo‐mechanical auxetic foam conversion parameters on the Young's modulus and Poisson's ratio of open‐cell polyurethane foam are related to changes in chemical bonding and cell structure. Applied volumetric compression, conversion temperature, and duration are reported on foam Young's modulus, Poisson's ratio, and structural stability. Fourier transform infrared spectral analysis on samples converted at and above 160 °C strongly indicates a hydrogen bond interaction increase in urea groups (C=O‐‐‐H‐N) and an increase in hydrogen bonding population. Spectral changes inferred soft segment degradation following extensive heat exposure (200 °C, 180 min), specifically a shift and intensity change in CH2and C‐O‐C polyol bands and a broad baseline increase between 3600 and 2400 cm−1. These changes are linked to (i) resistance to dimensional recovery over time and during re‐heating; (ii) Poisson's ratio becoming negative, then zero in tension or marginally positive in compression; (iii) Young's Modulus reducing then increasing; (iv) mass loss, evidenced by thermogravimetric analysis increasing from 150 °C. The minimum mean values of Poisson's ratio of ≈−0.2 (to 10% compression/tension) are comparable to other studies. All samples that retain their imposed compression over time are isotropic, with near constant Young's moduli and Poisson's ratio (to 10% compression/tension).
Efficient Charge Collection Promoted by Interface Passivation Using Amino Acid Toward High Performance Perovskite Solar Cells
Authors: Zhang Wenwen , Lei Xiaoli , Liu Jihong , Dong Jun , Yan Xuewen , Gao Wei , Dong Hua , Ran Chenxin , Wu Zhaoxin
Published: November 2018

Interfacial modification of organolead halide perovskites (OHPs) has shown to be a promising strategy to improve the quality of OHPs film. In this work, a bipolar amino acid molecule, L‐Leucine (LL), have been introduced to the anti‐solvent solution to induce the formation methylammonium lead triiodide (MAPbI3) perovskite films. The morphology, crystal structure, and optoelectronic property of perovskite films are systematically studied, where the bipolar LL plays a key role. By employing the LL‐modified perovskite film, the perovskite solar cells (PSCs) are well prepared. Consequently, a 18.2% efficiency was obtained from the champion device, which showed a significant improvement compared to the controlled device with a PCE of 16.1%. Our results demonstrate the crucial role of bipolar feature of interfacial modification agent on the charge transfer at the interface, and provide important interfacial modification concept on efficient PSCs. Moreover, significantly improved stability can be observed from the LL modified devices, benefiting from the effectively trap‐passivation.
Comparative terrestrial atmospheric circulation regimes in simplified global circulation models. Part II: Energy budgets and spectral transfers
Authors: Read Peter L. , Tabataba‐Vakili Fachreddin , Wang Yixiong , Augier Pierre , Lindborg Erik , Valeanu Alexandru , Young Roland M. B.
Published: November 2018

The energetics of possible global atmospheric circulation patterns in an Earth‐like atmosphere are explored using a simplified global General Circulation Model (GCM) based on the University of Hamburg's Portable University Model for the Atmosphere (designated here as PUMA‐S), forced by linear relaxation towards a prescribed temperature field and subject to Rayleigh surface drag and hyperdiffusive dissipation. Results from a series of simulations, obtained by varying planetary rotation rate Ω with an imposed equator‐to‐pole temperature difference, were analysed to determine the structure and magnitude of the heat transport and other contributions to the energy budget for the time‐averaged, equilibrated flow. These show clear trends with rotation rate, with the most intense Lorenz energy cycle for an Earth‐sized planet occurring with a rotation rate around half that of the present‐day Earth (i.e., Ω∗ = Ω/Ω
E
 = 1/2, where Ω
E
is the rotation rate of the Earth). Kinetic energy (KE) and available potential energy (APE) spectra, E

K
(n) and E

A
(n) (where n is total spherical wavenumber), also show clear trends with rotation rate, with n
−3 enstrophy‐dominated spectra around Ω∗ = 1 and steeper (∼n
−5) slopes in the zonal mean flow with little evidence for the n
−5/3 spectrum anticipated for an inverse KE cascade. Instead, both KE and APE spectra become almost flat at scales larger than the internal Rossby radius, L

d
, and exhibit near‐equipartition at high wavenumbers. At Ω∗ < <1, the spectrum becomes dominated by KE with E

K
(n)∼(2–3)E

A
(n) at most wavenumbers and a slope that tends towards n
−5/3 across most of the spectrum. Spectral flux calculations show that enstrophy and APE are almost always cascaded downscale, regardless of rotation rate. KE cascades are more complicated, however, with downscale transfers across almost all wavenumbers, dominated by horizontally divergent modes, for . At higher rotation rates, transfers of KE become increasingly dominated by rotational (horizontally nondivergent) components with strong upscale transfers (dominated by eddy–zonal flow interactions) for scales larger than L

d
and weaker downscale transfers for scales smaller than L

d
.
Evaluation of expiratory capacity with severe asthma following bronchial thermoplasty
Authors: Ishii Satoru , Iikura Motoyasu , Shimoda Yukiko , Izumi Shinyu , Hojo Masayuki , Sugiyama Haruhito
Published: November 2018

Bronchial thermoplasty (BT) is a bronchoscopic treatment to reduce the amount of smooth muscle in the bronchial wall in patients with severe asthma. Reducing smooth muscle in the airway wall reportedly alleviates air trapping and decreases expiratory volume. In the current study, expiratory computed tomography (CT) was performed in 10 patients who underwent BT at our facility, and their expiratory volume was evaluated. We observed an improvement in the expiratory volume on CT in nine of the 10 patients. Total expiratory lung volume decreased from 1693 ± 907 to 1426 ± 853 mL, indicating an improvement of approximately 15%. Use of CT for evaluation of expiratory volume may be a method for assessing the effectiveness of BT.
Machine learning methods for leveraging baseline covariate information to improve the efficiency of clinical trials
Authors: Zhang Zhiwei , Ma Shujie
Published: November 2018

Clinical trials are widely considered the gold standard for treatment evaluation, and they can be highly expensive in terms of time and money. The efficiency of clinical trials can be improved by incorporating information from baseline covariates that are related to clinical outcomes. This can be done by modifying an unadjusted treatment effect estimator with an augmentation term that involves a function of covariates. The optimal augmentation is well characterized in theory but must be estimated in practice. In this article, we investigate the use of machine learning methods to estimate the optimal augmentation. We consider and compare an indirect approach based on an estimated regression function and a direct approach that aims directly to minimize the asymptotic variance of the treatment effect estimator. Theoretical considerations and simulation results indicate that the direct approach is generally preferable over the indirect approach. The direct approach can be implemented using any existing prediction algorithm that can minimize a weighted sum of squared prediction errors. Many such prediction algorithms are available, and the super learning principle can be used to combine multiple algorithms into a super learner under the direct approach. The resulting direct super learner has a desirable oracle property, is easy to implement, and performs well in realistic settings. The proposed methodology is illustrated with real data from a stroke trial.
The First Systematic Study on the Conditions Affecting the Ionothermal Synthesis of Silicoaluminophosphates
Authors: Azim Muhammad Mohsin , Stark Annegret
Published: November 2018

The first systematic study on the ionothermal synthesis of silicoaluminophosphates (SAPOs) was performed to study the influence of reaction time, Si/Al or F/Al ratios and changing ionic liquid (cation, anion and alkyl group). The resulting materials were characterised by XRD, liquid (1H) and solid state (29Si) NMR, TPDA, SEM images, Volhard titration, as well as thermogravimetric and nitrogen sorption analyses. 1‐Butyl‐3‐methylimidazolium bromide ([C4mim]Br) as both solvent and structure‐directing agent (SDA) produced the AFI framework. It was found that the resulting Si/Al ratio of SAPO‐AFI increases with an increase in initial Si/Al ratio but decreases with F/Al ratio in the reaction mixture. Different ionic liquids giving the same framework type have no effect on the silicon uptake. The formation of Si‐islands is favoured at extended reaction times or higher silicon content. The framework type of SAPOs can be changed from AEL to AFI by changing either the alkyl chain from ethyl to butyl, substituting the C2‐position of the cation with a methyl moiety, or altering the cation (imidazolium vs. pyridinium). The framework selectivity was altered from AFI to LTA by changing the anion (of [C4py]Br to Cl−), and to CHA by 1‐methylimidazole addition. The first successful ionothermal synthesis of the AFI, LTA and CHA framework types of SAPOs is presented, providing a more efficient method than the conventional hydrothermal synthesis.
Rational Design of IR820‐ and Ce6‐Based Versatile Micelle for Single NIR Laser–Induced Imaging and Dual‐Modal Phototherapy
Authors: Hu Xu , Tian Hailong , Jiang Wei , Song Aixin , Li Zhonghao , Luan Yuxia
Published: November 2018

Phototherapy as a promising cancer diagnostic and therapeutic strategy has aroused extensive attention. However, single‐wavelength near‐infrared (NIR) light–triggered combinational treatment of photothermal therapy (PTT) and photodynamic therapy (PDT) is still a great challenge. Herein, a multifunctional micelle activated by a single‐wavelength laser for simultaneous PTT and PDT as well as fluorescence imaging is developed. Briefly, new indocyanine green (IR820) is conjugated to d‐α‐tocopheryl polyethylene glycol 1000 succinate (TPGS) via the linker 6‐aminocaproic acid, and then, chlorin e6 (Ce6) is encapsulated into the micelles formed by TPGS–IR820 conjugates to fabricate TPGS–IR820/Ce6 micelles. As the well‐designed TPGS–IR820 conjugate shares a similar peak absorption wavelength with Ce6, this micelle can be applied with a single NIR laser (660 nm). The stable micelles exhibit excellent photothermal conversion efficiency in vitro and in vivo as well as high singlet oxygen generation capacity in tumor cells. After efficient cellular internalization, the as‐prepared micelles display outstanding anticancer activity upon single NIR laser irradiation in vitro and in vivo. Furthermore, TPGS–IR820/Ce6 micelles show negligible systemic toxicity. The highly safe and effective TPGS–IR820/Ce6 micelles can offer an innovative strategy to construct single NIR light–induced PTT and PDT combined phototherapy nanoplatforms via suitable modification of organic phototherapeutic agents.
Construction of Soft Base Tongs on Separator to Grasp Polysulfides from Shuttling in Lithium–Sulfur Batteries
Authors: Dong Qin , Shen Runping , Li Cunpu , Gan Ruiyi , Ma Xiaotong , Wang Jianchuan , Li Jing , Wei Zidong
Published: November 2018

Rechargeable lithium–sulfur batteries, which use sulfur as the cathode material, promise great potentials to be the next‐generation high‐energy system. However, higher‐order lithium polysulfides, Li2Sx (x = 4, 6, and 8), regardless of in charge or in discharge, always form first, dissolve subsequently in the electrolyte, and shuttle to the cathode and the anode, which is called “shuttle effect.” The polysulfides shuttle effect leads to heavy loss of the active‐sulfur materials. Literature works mostly “cover or fill” the pores to block polysulfides from shuttling, which also hinder the lithium ion transfer. Here a protocol is invented to grasp polysulfides based on the “soft and hard acid–base” theory. Tertiary amine layer (TAL) polymerized on a polypropylene separator selectively coordinates with the dissolved high‐order Li2Sx in the cathode. Meanwhile, the transportation of lithium cations is not interrupted because of enough pores left for their transportation. After 400 cycles of charge/discharge at 0.5C, the TAL modified separator battery still possesses a capacity of 865 mAh g−1, which is among the best of the state‐of‐the‐art performances of lithium–sulfur batteries. The flexible “polysulfides tongs” construction method paves a new way for Li–S batteries to reach desired performances with less worry about polysulfides shuttle.
Building lightweight structures with carbon‐fiber‐reinforced polymer‐reinforced ultra‐high‐performance concrete: Research approach, construction materials, and conceptual design of three building components
Authors: Kromoser Benjamin , Preinstorfer Philipp , Kollegger Johann
Published: November 2018

The building industry, and especially the concrete industry, consumes a considerable proportion of the natural resources extracted from the lithosphere and is responsible for a large part of the solid waste generated worldwide. Unfortunately, this fact has not yet generated a movement to counter the trend; rather, a huge increase in the use of concrete in new structures can be observed. It is imperative to counteract this development by optimally exploiting the material properties of concrete in order to improve its efficiency. One strategy being pursued at the University of Natural Resources and Life Sciences, Vienna and TU Wien is to reduce the amount of concrete and reinforcement in structures by using high‐performance materials such as carbon‐fibre‐reinforced polymers (CFRP) in ultra‐high‐performance concrete (UHPC) members. This permits a crucial reduction in the self‐weight and allows for the design of very lightweight precast concrete elements. The authors' goal is to use CFRP rods as bending reinforcement and a combination of flat and preformed CFRP textiles as shear and structural reinforcement. In the first part of this paper, the research approach is introduced and a comprehensive overview of the state of the art of UHPC and CFRP reinforcement is given. The second part contains a description of the conceptual design of some structural members (one floor element and two T‐beams), starting with the development of a suitable UHPC mixture. Furthermore, preliminary uniaxial tensile tests of textile‐reinforced UHPC strips are described and evaluated. In the final part of this paper, the authors present parameter studies for different reinforcement types, values, additional prestressing of the rod reinforcement and the first prototypes. They are used to give an estimation of the feasibility, the load‐bearing and deflection behavior of the proposed building components.
Dynamic characteristics and seismic response of frame–core tube structures, considering soil–structure interactions
Authors: Shen Chao , Qian Deling
Published: November 2018

In order to study the dynamic characteristics and seismic response of high‐rise buildings with a frame–core tube structure, while considering the effect of soil–structure interactions (SSIs), a series of shaking table tests were conducted on test models with two foundation types: fixed‐base (FB), in which the superstructure was directly affixed to the shaking table, and SSI, consisting of a superstructure, pile foundation, and soil. To increase the applicability of the model to the dynamic characteristics of real‐world tall buildings, the superstructure of test models was built at a scale of 1/50. This simulated a 41‐floor high‐rise building with a frame–core tube structure. The mode shape, natural frequency, damping ratio, acceleration and displacement response, story shear, and dynamic strain were determined in each of the test models under the excitation of simulated minor, moderate, and large earthquakes. The SSI effect on frame–core tubes was analyzed by comparing the results of the two test models. The results show that the dynamic characteristics and seismic response of the two systems were significantly different. Finally, these results were verified by performing a numerical analysis on the differences in the seismic responses of the FB and SSI numerical models under various simulated seismic conditions.
Effect of poly(ethylene‐co‐vinyl acetate) additive on mechanical properties of maleic anhydride‐grafted acrylonitrile butadiene styrene for coating applications
Authors: Olongal Manaf , Mohamed Nainar Mohamed Ansari , Marakkattupurathe Manoj , Muslim Veettil Asharaf Shadiya , Athiyanathil Sujith
Published: November 2018

The Izod impact strength of maleic anhydride‐grafted acrylonitrile butadiene styrene (MA‐g‐ABS) copolymer has been improved by the use of rubbery poly(ethylene‐co‐vinyl acetate) (EVA). The MA‐g‐ABS is prepared by an internal mixer using dicumyl peroxide as free radical initiator, and the grafting degree was determined using back‐titration method. The amount of EVA is optimized by evaluating the Izod impact strength, tensile, and flexural properties of the samples. Addition of 6% EVA into MA‐g‐ABS system improved the Izod impact strength and tensile strength by 18% and 35%, respectively. The miscibility of EVA in ABS and MA‐g‐ABS matrices has been observed using differential scanning calorimetry and scanning electron microscopy techniques. The enhanced adhesion property exhibited by MA‐g‐ABS/EVA systems promises it as a good candidate for thermoplastic coating applications on aluminum substrates. J. VINYL ADDIT. TECHNOL., 25:287–295, 2019. © 2018 Society of Plastics Engineers
Continuous Hydrothermal Flow Synthesis of Co1–xNixFe2O4 (x = 0–0.8) Nanoparticles and Their Catalytic Properties for CO Oxidation and Oxygen Evolution Reaction
Authors: Xu Yu , Özcan Fatih , Zielke Philipp , Becker Stefanie , Heimann Manuel , Heese Justus , Chakrapani Kalapu , Behrens Malte , Bredmose Simonsen Søren , Norby Poul , Vang Hendriksen Peter , Kiebach Ragnar
Published: November 2018

Well‐crystallized CoFe2O4 and Ni‐substituted Co1–xNixFe2O4 nanoparticles (x = 0.1, 0.3, 0.4, 0.5, 0.6, 0.8) were synthesized by continuous hydrothermal flow synthesis (CHFS). Catalytic properties of the synthesized nanoparticles in the catalytic oxidation of CO and electrochemical oxygen evolution reaction (OER) were studied. A conversion of 50 % in CO was reached at 223 °C and 100 % at 310 °C when CoFe2O4 prepared by CHFS was used as catalyst. The effect of Ni content on the OER activity of the as‐synthesized Co1–xNixFe2O4 did not show a clear trend, however a remarkable improvement of the activity was observed for 30 at % substitution (x = 0.3) in Co0.7Ni0.3Fe2O4.
Introduction
Authors: Scholten Peter , Crul Maurice , van de Laar Paul
Published: November 2018

Migration-related diversity manifests itself primarily in cities. Cities are usually the primary points of entry for new migrants and often the first places where integration in society starts. Many cities have experienced centuries of immigration and consider migration as a core element of their identity (such as New York and Amsterdam). In an increasing number of Western European cities, even more than half of the population has a migration background. These cities are referred to as ‘majority-minority’ cities. In Europe, this is already true for cities like Amsterdam, Rotterdam, Brussels or Malmö and substantial parts of greater London, Frankfurt or Paris. Of the children under the age of fifteen in Amsterdam and Rotterdam only one third is still of Dutch descent (Crul 2016).
The ‘Integration’ of People of Dutch Descent in Superdiverse Neighbourhoods
Authors: Crul Maurice , Lelie Frans
Published: November 2018

In the past 40 years, researchers into migration and integration have focussed almost exclusively on migrants and their children. This one-sided focus has persisted, even though it is generally acknowledged that integration is a two-way process in which not only migrants, but also the established population play an important role (see, for example, Garces-Mascareňas and Penninx 2016; Martinovic 2013). Amsterdam and Rotterdam have both become majority-minority cities where now all ethnic population groups – including that of Dutch descent – form a numerical minority. This new reality makes it even more urgent to examine the group without a migration background. In cities like Amsterdam and Rotterdam, only one out of three young people under the age of 15 are of Dutch descent (Crul 2016). The transformation of the former majority group to a numerical minority group may well be one of the most significant urban transformations of our time. The current backlash against migrants and refugees has made it clear that the integration of people of Dutch descent into today’s superdiverse majority-minority neighbourhoods and cities is a topic that begs attention.