bluuebunny/crossref_metadata_2025 huggingface dataset:
Solvent Effect on the Photoinduced Structural Change of a Phosphorescent Molecular Butterfly
Authors: Ma Ying‐Zhong , Zhou Chenkun , Doughty Benjamin , Easley Davis C. , Deterding Justin , Ma Biwu
Published: October 2017

Photoinduced structural changes (PSC) is one of the fundamental excited‐state dynamic processes, and yet often very challenging to distinguish from competing electronic excited‐state relaxation channels having similar or even comparable timescales. Here, we report a detailed study on the PSC of a pyrazolate bridged platinum(II) binuclear complex, BFPtPZ (C^NPt(μ‐pz′)2PtC^N, C^N=2‐(2,4‐difluorophenyl)pyridine, pz′=pyrazolate), a molecular butterfly, using time‐correlated single photon counting measurements at different wavelengths and sample temperatures. Analysis of the results obtained using dichloromethane (DCM) and ethylene carbonate (EC) as solvents enabled us to reveal an unexpected, strong solvent effect on the PSC processes. We show that a rapid PSC process with a characteristic timescale of 323 ps is observed in DCM, which leads to an excitation equilibrium between the ligand center/metal‐to‐ligand charge transfer (3LC/MLCT) and metal‐metal‐to‐ligand charge transfer (3MMLCT) triplet states. The subsequent relaxation from these electronic states to the ground state takes place in several nanoseconds. In contrast, the corresponding PSC process in EC appears slow at all temperatures studied in our experiments and showed no sign of such excitation equilibrium. The observed solvent effect is found to arise from distinct solvent properties including their viscosities and polarities as well as the peculiar electronic excited‐states of the butterfly‐like molecules with charge transfer character.
Synthesis and Photophysical Characterization of 2,3‐Dihydroquinolin‐4‐imines: New Fluorophores with Color‐Tailored Emission
Authors: Chou Chih‐Hung , Rajagopal Basker , Liang Chien‐Fu , Chen Kuan‐Lin , Jin Dun‐Yuan , Chen Hsing‐Yin , Tu Hsiu‐Chung , Shen Yu‐Ying , Lin Po‐Chiao
Published: October 2017

In this study, a series of variously substituted 2,3‐dihydroquinolin‐4‐imines (DQIs) were synthesized from N‐substituted propargylanilines by copper(I)‐catalyzed annulation. The approach adopted in this study under mild, effective conditions exhibited broad substrate tolerance, particularly for functional groups substituted on anilines. Most of the DQI derivatives synthesized under optimal conditions were obtained in good isolated yields of 63–88 %. 2,3‐Dihydroquinolinimine thus obtained was easily converted to important structures like 2,3‐dihydroquinolone and tetrahydrobenzodiazepin‐5‐one, confirming the importance of this strategy in constructing various heterocycles. Surprisingly, 2,3‐dihydroquinolinimines thus obtained exhibited bright fluorescence with quantum yields up to 66 %. The density functional theory (DFT) and time‐dependent DFT (TD‐DFT) calculations were performed for understanding the excited‐state nature of DQI system. Accordingly, a tailored DQI derivative bearing methoxy group at C‐6 position and acetoxy group at C‐7 position was designed and synthesized to give emission at 559 nm with redshift compared to the 7‐methoxy substituted DQI. A detailed study of DQI structures with their photophysical properties was performed with five control molecules and consequently demonstrated the uniqueness of the chemical structures of DQIs.
Transuranic Computational Chemistry
Authors: Kaltsoyannis Nikolas
Published: October 2017

Recent developments in the chemistry of the transuranic elements are surveyed, with particular emphasis on computational contributions. Examples are drawn from molecular coordination and organometallic chemistry, and from the study of extended solid systems. The role of the metal valence orbitals in covalent bonding is a particular focus, especially the consequences of the stabilization of the 5f orbitals as the actinide series is traversed. The fledgling chemistry of transuranic elements in the +II oxidation state is highlighted. Throughout, the symbiotic interplay of experimental and computational studies is emphasized; the extraordinary challenges of experimental transuranic chemistry afford computational chemistry a particularly valuable role at the frontier of the periodic table.
International Inbound Open Innovation and International Performance
Authors: Romero‐Martínez Ana M. , García‐Muiña Fernando E. , Ghauri Pervez N.
Published: October 2017

This work analyzes the relationship between international inbound open innovation and international performance,including the complementary role played by firms' intellectual capital. Based on a survey of 8,973 Spanish manufacturing firms, the findings confirm that externalization by means of international inbound open innovation, both strategically and financially, favours international performance measured in terms of international patents. Regarding the moderating effect of intellectual capital, the results show that both human and technological capital boost the impact of international inbound open innovation on international performance. Organizational capital also increases the benefits of financial inbound open innovation; however, it impacts negatively in the case of strategic inbound open innovation. The additional benefits of externalization may add extra value to international performance. Copyright © 2017 ASAC. Published by John Wiley & Sons, Ltd.
Synthesis and Determination of Lipophilicity, Anticonvulsant Activity, and Preliminary Safety of 3‐Substituted and 3‐Unsubstituted N‐[(4‐Arylpiperazin‐1‐yl)alkyl]pyrrolidine‐2,5‐dione Derivatives
Authors: Rybka Sabina , Obniska Jolanta , Żmudzki Paweł , Koczurkiewicz Paulina , Wójcik‐Pszczoła Katarzyna , Pękala Elżbieta , Bryła Adrian , Rapacz Anna
Published: October 2017

A new series of 1,3‐substituted pyrrolidine‐2,5‐dione derivatives as potential anticonvulsant agents are described. Initial pharmacological screening of these compounds was performed by using acute models of seizures (MES and scPTZ tests) in mice after intraperitoneal administration. Quantitative pharmacological research revealed that the most promising compounds were N‐[{4‐(3‐trifluoromethylphenyl)piperazin‐1‐yl}propyl]‐3‐benzhydrylpyrrolidine‐2,5‐dione monohydrochloride (11) with a ED50 value of 75.9 mg kg−1 (MES test) and N‐[{4‐(3,4‐dichlorophenyl)piperazin‐1‐yl}ethyl]‐3‐methylpyrrolidine‐2,5‐dione monohydrochloride (18) with ED50=88.2 mg kg−1 (MES test) and ED50=65.7 kg mg−1 (scPTZ test). These compounds displayed a more beneficial protective index than well‐known antiepileptic drugs. A plausible mechanism of action of compounds 11 and 18 [molecule 11 blocked the sodium channel (site 2) and 18 blocked both the sodium (site 2) and L‐type calcium channels] and their preliminary safety in vitro were evaluated. Besides, the lipophilicity of all synthesized compounds was determined by using UPLC–MS.
Co‐Differentiation of Human Pluripotent Stem Cells‐Derived Cardiomyocytes and Endothelial Cells from Cardiac Mesoderm Provides a Three‐Dimensional Model of Cardiac Microtissue
Authors: Giacomelli Elisa , Bellin Milena , Orlova Valeria V. , Mummery Christine L.
Published: October 2017

The formation of cardiac mesodermal subtypes is highly regulated in time and space during heart development. In vitro models based on human pluripotent stem cells (hPS cells) provide opportunities to study mechanisms underlying fate choices governing lineage specification from common cardiovascular progenitors in human embryos. The generation of cardiac endothelial cells in particular allows the creation of complex models of cardiovascular disorders in which either cardiomyocytes or endothelial cells are affected. Here, a protocol for co‐differentiation of cardiomyocytes and endothelial cells from cardiac mesoderm using hPS cells is described. Precise details for the enrichment of each cell population from heterogeneous‐differentiated cultures, a description of how to maintain and dissociate enriched cardiomyocytes, and the expansion and cryopreservation of enriched endothelial cells are all provided. The generation and culture of three‐dimensional cardiac microtissues from these cell populations is described and guidelines for the characterization of microtissues by immunofluorescent staining and re‐plating for downstream applications are provided. © 2017 by John Wiley & Sons, Inc.
An identity attribute–based encryption using elliptic curve digital signature for patient health record maintenance
Authors: Athena J. , Sumathy V. , Kumar K.
Published: October 2017

Providing security to the data that stored in personal health record (PHR) is an emerging and critical task in recent years. For this purpose, some of the encryption and key generation techniques are developed in the traditional works. But it has the drawbacks such as lacks in access control policies, reduced security, and ineffective. So this work implemented the efficient techniques, namely, elliptic curve Diffie‐Hellman for the secret key generation and identity attribute–based encryption for improving the security of the cloud data. Initially, the cloud user can request the patient's data to the PHR admin, and then they can generate the secret by using the elliptic curve Diffie‐Hellman algorithm. The key that used for encryption and decryption is generated by using the identity attribute–based encryption technique. Then, the access control is provided to the users based on their roles. The requested data are encrypted by applying the advanced encryption standard technique. After that, the elliptic curve digital signature algorithm is used to generate the digital signature for the encrypted data. Furthermore, it is verified with the user's digital signature; if it matches, the data can be accessed by the user with the help of advanced encryption standard decryption mechanism. Finally, the authenticated user can able to access the patient's data from PHR. In experiments, the performance of the proposed encryption and key generation technique is evaluated and compared with the existing techniques for proving the effectiveness of the implemented system.
Connectivity, persistence, and loss of high abundance areas of a recovering marine fish population in the Northwest Atlantic Ocean
Authors: Boudreau Stephanie A. , Shackell Nancy L. , Carson Stuart , den Heyer Cornelia E.
Published: October 2017

In the early 1990s, the Northwest Atlantic Ocean underwent a fisheries‐driven ecosystem shift. Today, the iconic cod (Gadus morhua) remains at low levels, while Atlantic halibut (Hippoglossus hippoglossus) has been increasing since the mid‐2000s, concomitant with increasing interest from the fishing industry. Currently, our knowledge about halibut ecology is limited, and the lack of recovery in other collapsed groundfish populations has highlighted the danger of overfishing local concentrations. Here, we apply a Bayesian hierarchical spatiotemporal approach to model the spatial structure of juvenile Atlantic halibut over 36 years and three fisheries management regimes using three model parameters to characterize the resulting spatiotemporal abundance structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). Two areas of high juvenile abundance persisted through three decades whereas two in the northeast are now diminished, despite the increased abundance and landings throughout the management units. The persistent areas overlap with full and seasonal area closures, which may act as refuges from fishing. Connectivity was estimated to be 250 km, an order of magnitude less than the distance assumed by the definition of the Canadian management units (~2,000 km). The underlying question of whether there are distinct populations within the southern stock unit cannot be answered with this model, but the smaller ~250 km scale of coherent temporal patterns suggests more complex population structure than previously thought, which should be taken into consideration by fishery management.
Payments for Ecosystem Services as a Policy Mix: Demonstrating the institutional analysis and development framework on conservation policy instruments
Authors: Barton David N. , Benavides Karla , Chacon‐Cascante Adriana , Le Coq Jean‐Francois , Quiros Miriam Miranda , Porras Ina , Primmer Eeva , Ring Irene
Published: October 2017

Policy mix analysis has been applied in research on energy, climate, urban and transport policy, and more recently biodiversity conservation and ecosystem services. However, policy mix analysis has thus far been employed at a high conceptual level, focusing on describing interactions between instrument types. Policy mix analysis rarely describes instrument ‘structure’ or functional characteristics in a way that would answer the question ‘what constitutes an instrument’? We describe how the rules‐in‐use taxonomy of the Institutional Analysis and Development (IAD) framework, developed for research on common pool resource management, can be used to characterize conservation policy instrument interactions. We demonstrate the approach on the well‐known payments for ecosystem services (PES) program in Costa Rica and cross‐compliance policies, arguing that PES is a policy mix rather than a single economic instrument. Our analysis shows how design features of PES described in the economics literature map to ‘rules‐in‐use’ in the IAD framework. The framework provides a terminology for defining what constitutes institutional context, comparing economic, regulatory and information instruments, and studying their interactions. The rules‐in‐use taxonomy of IAD is a ‘structural’ diagnostic approach, which needs to be combined with other tools that analyse the role and ‘agency’ of actors, as part of integrative environmental governance research. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
The Economic and Legal Sides of Additionality in Payments for Environmental Services
Authors: Karsenty Alain , Aubert Sigrid , Brimont Laura , Dutilly Céline , Desbureaux Sébastien , Ezzine de Blas Driss , Le Velly Gwenole
Published: October 2017

This paper aims to clarify two distinct but complementary questions on economic and legal additionality in the payments for environmental services (PES) debate based on examples from the literature and direct observations made in Madagascar and Mexico. For the economic dimension of additionality, we explain two ‘regimes of justification’, efficiency on the one hand and social equity on the other, and discuss how analysts position themselves with regard to both regimes. For the legal dimension, we review and analyse specific cases in which PES are implemented in addition to existing environmental regulations. We propose a renewed framework of analysis to distinguish ‘compensation’ and ‘reward’ in PES by crossing the opportunity cost dimension and the legal constraint vis‐à‐vis the environment. We show how difficult it is to fully maintain the objective of efficiency when PES are implemented simultaneously across different combinations of opportunity costs and regulation constraints. We propose policy options to address the contradiction between incentive and coercive instruments. These options are land sparing, social targeting and chronological combinations. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Promotion of phenolic compounds production in Salvia miltiorrhiza hairy roots by six strains of rhizosphere bacteria
Authors: You Hong , Yang Suijuan , Zhang Lu , Hu Xiufang , Li Ou
Published: October 2017

Salvia miltiorrhiza Bunge is an important herb for the treatment of cerebrovascular and cardiovascular diseases with bioactive compounds (phenolic acids and tanshinones). Abundant studies showed that tanshinones could be stimulated by biotic and abiotic stresses, but limited information is available on biosynthesis of phenolic acids promoted by biotic stresses. The aim of the present work was to isolate and identify rhizosphere bacteria which stimulated phenolic compound in Salvia miltiorrhiza hairy roots and investigated the internal mechanism, providing a potential means to enhance content of pharmaceuticals in S. miltiorrhiza. The results showed that six bacteria, namely, HYR1, HYR26, SCR22, 14DSR23, DS6, and LNHR13, belonging to the genus Pseudomonas and Pantoea, significantly promoted the growth and content of major phenolic acids, RA and SAB. Bacteria LNHR13 was the most effective one, with the contents of RA and SAB reaching ∼2.5‐fold (30.1 mg/g DW) and ∼2.3‐fold (48.3 mg/g DW) as those of the control, respectively. Phytohormones and polysaccharides produced by bacteria showed potential responsibility for the growth and biosynthesis of secondary metabolites of S. miltiorrhiza. Meanwhile, we found that the more abundant the types and contents of phytohormones, the stronger their stimulating effect on the content of salvianolic acids.
Relative reductions in health care utilization among young adults before aging out of extended dependent coverage
Authors: Chen Weiwei
Published: October 2017

The 2010 Affordable Care Act extended dependent coverage for adult children up to age 26 in the USA. Since then, considerable studies have assessed its various impacts among young adults. However, little is known about whether there is any change in health care use when young adults age out of dependent coverage. This study examines health care consumption changes among young adults prior to their aging out process. I used data from a large insurance claim database and studied health care utilization of young adults under parents' coverage during a 2‐year period in a difference‐in‐difference framework. I found that young adults had relative reductions in health services use, except ER visits, compared with individuals who stayed under parents' coverage. This pattern was the same for both male and females. Individuals with regular medical needs had greater relative reductions compared with those without regular medical needs. The relative reductions in health care use during the aging out process may have an important impact on young adults' health, especially for those with regular medical needs. More efforts could be made to help them maintain regular medical utilization during the transition.
Sustained FXN expression in dorsal root ganglia from a nonreplicative genomic HSV‐1 vector
Authors: Ventosa Maria , Wu Zetang , Lim Filip
Published: October 2017

Background

Friedreich's ataxia (FA) is an autosomal recessive neurodegenerative disease caused by mutations in the frataxin gene (FXN), which lead to reduced levels of the essential mitochondrial protein frataxin. Currently, there is no effective cure.

Methods

With the aim of developing a gene therapy for FA neuropathology, we describe the construction and preliminary characterization of a high‐capacity nonreplicative genomic herpes simplex virus type 1 vector (H24B‐FXNlac vector) carrying a reduced version of the human FXN genomic locus, comprising the 5‐kb promoter and the FXN cDNA with the inclusion of intron 1.

Results

We show that the transgene cassette contains the elements necessary to preserve physiological neuronal regulation of human FXN expression. Transduction of cultured fetal rat dorsal root ganglia neurons with the H24B‐FXNlac vector results in sustained expression of human FXN transcripts and frataxin protein. Rat footpad inoculation with the H24B‐FXNlac vector results in human FXN transgene delivery to the dorsal root ganglia, with expression persisting for at least 1 month.

Conclusions

The results of the present study support the feasibility of using this vector for sustained neuronal expression of human frataxin for FA gene therapy.
Sagittal plane walking patterns are related to MRI changes over 18‐months in people with and without mild‐moderate hip osteoarthritis
Authors: Kumar Deepak , Wyatt Cory , Lee Sonia , Okazaki Narihiro , Chiba Ko , Link Thomas M. , Souza Richard B. , Majumdar Sharmila
Published: October 2017

The purpose was to evaluate the association of sagittal plane gait mechanics with MRI changes in the hip joint over 18‐months. Subjects with and without radiographic hip OA (n = 57) underwent MRI at baseline and 18 months for grading of cartilage lesions, bone marrow lesions (BML), cysts, and labral tears. 3D gait analyses at baseline were used for sagittal plane hip kinematics and kinetics during the stance phase. Subjects were classified as progressors or non‐progressors based on increase in any MRI OA parameter. Multivariate ANOVA were used for differences in sagittal gait parameters between progressors and non‐progressors at baseline while adjusting for age. Logistic regression was used to estimate the probability of being classified as a progressor or non‐progressor with increasing hip flexion while adjusting for age, BMI, sex, and presence of radiographic hip OA. Of the 57, 35 were classified as non‐progressors and 22 were classified as progressors. At baseline, the progressors walked with 4.5° greater hip flexion during early stance (p = 0.021) and 3.5° lesser hip extension in late stance that was nearly significant (p = 0.059). Walking with greater hip flexion at baseline was associated with a greater risk of increase in MRI defined structural changes in the hip joint (Odds Ratio = 1.1, p = 0.038). Greater hip flexion during walking was associated with a risk of structural progression of hip OA. The results may guide future interventions to alter the walking patterns and slow structural hip OA progression.© 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1472–1477, 2018.
Preparation and evaluation of diblock copolymer‐grafted silica by sequential surface initiated‐atom transfer radical polymerization for reverse‐phase/ion‐exchange mixed‐mode chromatography
Authors: Bo Chun Miao , Wang Chaozhan , Wei Yin Mao
Published: October 2017

A novel approach that involved the grafting of diblock copolymer with two types of monomer onto substrate by sequential surface initiated‐atom transfer radical polymerization was proposed to prepare a mixed‐mode chromatographic stationary phase. The distinguishing feature of this method is that it can be applied in the preparation of various mixed‐mode stationary phases. In this study, a new reverse‐phase/ion‐exchange stationary phase was prepared by grafting hydrophobic styrene and cationic sodium 4‐styrenesulfonate by the proposed approach onto silica surface. The chromatographic properties of the prepared stationary phase were evaluated by the separation of benzene derivatives, anilines, and β‐agonists, and by the effect of pH values and acetonitrile content on the retention. Compared with typical RP columns, the prepared stationary phase achieved the better resolution and higher selectivity at a shorter separation time and lower organic content. Moreover, the application of the prepared column was proved by separating widely distributed polar and charged compounds simultaneously.
Development of a quantitative intracranial vascular features extraction tool on 3DMRA using semiautomated open‐curve active contour vessel tracing
Authors: Chen Li , Mossa‐Basha Mahmud , Balu Niranjan , Canton Gador , Sun Jie , Pimentel Kristi , Hatsukami Thomas S. , Hwang Jenq‐Neng , Yuan Chun
Published: October 2017

Purpose

To develop a quantitative intracranial artery measurement technique to extract comprehensive artery features from time‐of‐flight MR angiography (MRA).

Methods

By semiautomatically tracing arteries based on an open‐curve active contour model in a graphical user interface, 12 basic morphometric features and 16 basic intensity features for each artery were identified. Arteries were then classified as one of 24 types using prediction from a probability model. Based on the anatomical structures, features were integrated within 34 vascular groups for regional features of vascular trees. Eight 3D MRA acquisitions with intracranial atherosclerosis were assessed to validate this technique.

Results

Arterial tracings were validated by an experienced neuroradiologist who checked agreement at bifurcation and stenosis locations. This technique achieved 94% sensitivity and 85% positive predictive values (PPV) for bifurcations, and 85% sensitivity and PPV for stenosis. Up to 1,456 features, such as length, volume, and averaged signal intensity for each artery, as well as vascular group in each of the MRA images, could be extracted to comprehensively reflect characteristics, distribution, and connectivity of arteries. Length for the M1 segment of the middle cerebral artery extracted by this technique was compared with reviewer‐measured results, and the intraclass correlation coefficient was 0.97.

Conclusion

A semiautomated quantitative method to trace, label, and measure intracranial arteries from 3D‐MRA was developed and validated. This technique can be used to facilitate quantitative intracranial vascular research, such as studying cerebrovascular adaptation to aging and disease conditions. Magn Reson Med 79:3229–3238, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Quantification of particle crushing in consideration of grading evolution of granular soils in biaxial shearing: A probability‐based model
Authors: Cheng Zhuang , Wang Jianfeng
Published: October 2017

A probability‐based model is presented to estimate particle crushing and the associated grading evolution in granular soils during isotropic compression and prepeak shearing in biaxial tests. The model is based on probability density functions of interparticle and intraparticle stress (ie, particle normalized maximum shear stress and particle average maximum shear stress) derived from discrete element method simulations of biaxial tests. We find that the probability density functions of normalized maximum shear stress are dependent on the current sample grading, implying coupling effects between particle crushing and sample grading such that the particle crushing is affected by the current sample grading, and the grading change is also dependent on the current particle crushing extent. To incorporate these coupling effects into the model, particle crushing and grading change are calculated for each load increment, in which the crushing probability of a particle during any loading increment is denoted as the corresponding increment of probability of the internal maximum shear stress exceeding its maximum shear strength. The model shows qualitative agreement with published experimental data. The effects of the model parameters, including initial porosity, particle strength, initial grading, and crushing mode, on the calculated results are discussed and compared with previous studies. Finally, the strengths and limitations of the model are discussed.
Simultaneous imaging of hyperpolarized [1,4‐13C2]fumarate, [1‐13C]pyruvate and 18F–FDG in a rat model of necrosis in a clinical PET/MR scanner
Authors: Eldirdiri Abubakr , Clemmensen Andreas , Bowen Sean , Kjær Andreas , Ardenkjær‐Larsen Jan Henrik
Published: October 2017

A co‐polarization scheme for [1,4‐13C2]fumarate and [1‐13C]pyruvate is presented to simultaneously assess necrosis and metabolism in rats with hyperpolarized 13C magnetic resonance (MR). The co‐polarization was performed in a SPINlab polarizer. In addition, the feasibility of simultaneous positron emission tomography (PET) and MR of small animals with a clinical PET/MR scanner is demonstrated. The hyperpolarized metabolic MR and PET was demonstrated in a rat model of necrosis. The polarization and T1 of the co‐polarized [1,4‐13C2]fumarate and [1‐13C]pyruvate substrates were measured in vitro and compared with those obtained when the substrates were polarized individually. A polarization of 36 ± 4% for fumarate and 37 ± 6% for pyruvate was obtained. We found no significant difference in the polarization and T1 values between the dual and single substrate polarization. Rats weighing about 400 g were injected intramuscularly in one of the hind legs with 200 μL of turpentine to induce necrosis. Two hours later, 13C metabolic maps were obtained with a chemical shift imaging sequence (16 × 16) with a resolution of 3.1 × 5.0 × 25.0 mm3. The 13C spectroscopic images were acquired in 12 s, followed by an 8‐min 18F‐2‐fluoro‐2‐deoxy‐d‐glucose (18F–FDG) PET acquisition with a resolution of 3.5 mm. [1,4‐13C2]Malate was observed from the tissue injected with turpentine indicating necrosis. Normal [1‐13C]pyruvate metabolism and 18F–FDG uptake were observed from the same tissue. The proposed co‐polarization scheme provides a means to utilize multiple imaging agents simultaneously, and thus to probe various metabolic pathways in a single examination. Moreover, it demonstrates the feasibility of small animal research on a clinical PET/MR scanner for combined PET and hyperpolarized metabolic MR.
Density‐weighted concentric rings k‐space trajectory for 1H magnetic resonance spectroscopic imaging at 7 T
Authors: Chiew Mark , Jiang Wenwen , Burns Brian , Larson Peder , Steel Adam , Jezzard Peter , Albert Thomas M. , Emir Uzay E.
Published: October 2017

It has been shown that density‐weighted (DW) k‐space sampling with spiral and conventional phase encoding trajectories reduces spatial side lobes in magnetic resonance spectroscopic imaging (MRSI). In this study, we propose a new concentric ring trajectory (CRT) for DW‐MRSI that samples k‐space with a density that is proportional to a spatial, isotropic Hanning window. The properties of two different DW‐CRTs were compared against a radially equidistant (RE) CRT and an echo‐planar spectroscopic imaging (EPSI) trajectory in simulations, phantoms and in vivo experiments. These experiments, conducted at 7 T with a fixed nominal voxel size and matched acquisition times, revealed that the two DW‐CRT designs improved the shape of the spatial response function by suppressing side lobes, also resulting in improved signal‐to‐noise ratio (SNR). High‐quality spectra were acquired for all trajectories from a specific region of interest in the motor cortex with an in‐plane resolution of 7.5 × 7.5 mm2 in 8 min 3 s. Due to hardware limitations, high‐spatial‐resolution spectra with an in‐plane resolution of 5 × 5 mm2 and an acquisition time of 12 min 48 s were acquired only for the RE and one of the DW‐CRT trajectories and not for EPSI. For all phantom and in vivo experiments, DW‐CRTs resulted in the highest SNR. The achieved in vivo spectral quality of the DW‐CRT method allowed for reliable metabolic mapping of eight metabolites including N‐acetylaspartylglutamate, γ‐aminobutyric acid and glutathione with Cramér‐Rao lower bounds below 50%, using an LCModel analysis. Finally, high‐quality metabolic mapping of a whole brain slice using DW‐CRT was achieved with a high in‐plane resolution of 5 × 5 mm2 in a healthy subject. These findings demonstrate that our DW‐CRT MRSI technique can perform robustly on MRI systems and within a clinically feasible acquisition time.
Fabrication of flame retardant benzoxazine semi‐biocomposites reinforced by ramie fabrics with bio‐based flame retardant coating
Authors: Yan Hongqiang , Li Nannan , Cheng Jie , Song Pingan , Fang Zhengping , Wang Hao
Published: October 2017

Natural fibers reinforced benzoxazine bio‐composites are one class of highly attractive engineering materials in automobile, train and aerospace fields because of high thermal stability, good mechanical and improved biodegradability properties. Unfortunately, their poor interface and flammability issues remain unsatisfactorily addressed to date. Herein, we have demonstrated the fabrication of benzoxazine semi‐biocomposites reinforced by ramie fabric which was coated with bio‐based poly(diphenolic acid‐phenyl phosphate) (poly[DPA‐PDCP]) and polyethylenimine (PEI) via layer‐by‐layer self‐assembly method. The results show that the presence of poly(DPA‐PDCP)/PEI coating can significantly improve the interfacial adhesion between fabric and the resin matrix. This enables the tensile strength and flexural strength of as‐prepared semi‐biocomposite to increase by 53% (68.7 MPa) and 113% (120 MPa), respectively. In addition, the resultant semi‐biocomposite shows superior flame retardancy with a V‐0 rating achieved in the UL‐94 test. This work offers an effective approach to fabricate strong and flame retardant benzoxazine semi‐biocomposites. POLYM COMPOS., 39:E480–E488, 2018. © 2017 Society of Plastics Engineers
Radiation attenuation capability and flow characteristics of HDPE composite loaded with W, MoS2, and B4C
Authors: Afshar Maryam , Morshedian Jalil , Ahmadi Shervin
Published: October 2017

Shielding radiation from both x‐rays and gamma‐rays is important for personnel in medical fields, for example, interventional radiology, nuclear power stations, and other facilities where radiation is involved. Lead is known for its effective shielding property; however heaviness and toxicity are its main drawback. In this study effectiveness of non‐lead polymeric composite materials, which include high‐atomic‐number (powders of spherical W and lamellar MoS2)/or known barrier elements to absorb photons from the radiations (lamellar B4C) was evaluated. HDPE and particulate fillers were melt mixed in an internal mixer. Goodness of dispersion was manifested via SEM and EDX images. Radiation attenuation capability of samples was examined with direct diagnostic x‐ray exposure. Dynamic rheology measurements were carried out to evaluate viscoelastic properties, necessary in shaping process operations. Mechanical and thermal properties were further investigated from the product performance point of view. Results demonstrated that the flexible composite sheet of HDPE/45% (wt) W provided comparable x‐ray absorption to non‐flexible lead sheet but much lighter in weight. Significant difference was observed between flow characteristics and yield strength of composite materials of highly loaded spherical and lamellar particles. Melt viscoelastic behavior of former was similar to that of neat matrix melt. POLYM. COMPOS., 40:149–158, 2019. © 2017 Society of Plastics Engineers
Luminescence Spectroscopy of Bound Excitons in Diamond
Authors: Barjon Julien
Published: October 2017

Since the research on diamond doping remains an issue for electronic applications, the luminescence spectroscopy of bound excitons appears essential to evaluate the properties of shallow dopants in diamond. In this paper, the formation and recombination processes of bound excitons in diamond are reviewed for boron acceptors, phosphorus, and arsenic donors. Pulsed and continuous excitations are considered, the latter being currently used for the measurement of donor and acceptor concentrations in diamond.
Structure and Energetics of Embedded Si Patterns in Graphene
Authors: Nosraty Alamdary Daryoush , Kotakoski Jani , Susi Toma
Published: October 2017

Recent experiments have revealed the possibility of precise electron beam manipulation of silicon impurities in graphene. Motivated by these findings and studies on metal surface quantum corrals, the question arises what kind of embedded Si structures are possible within the hexagonal lattice, and how these are limited by the distortion caused by the preference of Si for sp3 hybridization. In this work, we study the geometry and stability of elementary Si patterns in graphene, including lines, hexagons, triangles, circles, and squares. Due to the size of the required unit cells, to obtain the relaxed geometries we use an empirical bond‐order potential as a starting point for density functional theory. Despite some interesting discrepancies, the classical geometries provide an effective route for the simulation of large structures.
Effects of Rubiadin isolated from Prismatomeris connata on anti‐hepatitis B virus activity in vitro
Authors: Peng Zheng , Fang Gang , Peng Fenghui , Pan Zhiyu , Su Zhengying , Tian Wei , Li Danrong , Hou Huaxin
Published: October 2017

Prismatomeris connata was a kind of Rubiaceae plant for treatment of hepatitis, hepatic fibrosis and silicosis. Whereas, the effective components of Prismatomeris connata remains unexplored. The aim of this study was to investigate the inhibitory effects and mechanisms of Rubiadin isolated from Prismatomeris connata against HBV using HepG2.2.15 cells. The levels of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and hepatitis B core antigen (HBcAg) in the supernatants or cytoplasm were examined using by enzyme‐linked immunosorbent assay. HBV DNA was qualified q‐PCR. Rubiadin was isolated by silica gel column. The structure of the compound was elucidated by HPLC, FT‐IR, 1H‐NMR, 13C‐NMR and identified as 1,3‐Dihydroxy‐2‐methyl‐9, 10‐anthraquinone. Rubiadin significantly decreased HBeAg,HBcAg secretion level and inhibit HBV DNA replication. Rubiadin inhibits the proliferation of the cells and HBx protein expression in a dose‐dependent manner. The intracellular calcium concentration was significantly reduced. These results demonstrated that Rubiadin could inhibit HepG2.2.15 cells proliferation, reduce the level of HBx expression, and intracellular free calcium, which might become a novel anti‐HBV drug candidate.
Pharmacological and chemical features of Nepeta L. genus: Its importance as a therapeutic agent
Authors: Süntar Ipek , Nabavi Seyed Mohammad , Barreca Davide , Fischer Nicolas , Efferth Thomas
Published: October 2017

Medicinal plants have always had great value for the human population due to their valuable constituents and potential bioactivities. The objective of this review is to present an updated overview of an important medicinal plant genus Nepeta L., from the family Lamiaceae, revealing its traditional utilization, biological activity, phytoconstituents, and mechanisms of action. For this purpose, a literature survey was carried out by using SciFinder, ScienceDirect, Scopus, PubMed, and Web of Science followed by a revision of the bibliographies of the related articles. We have described and analyzed the role of plants in drug discovery and the importance of Nepeta species. Information on the utilization purposes of Nepeta species in folk medicine has been emphasized, and scientific studies on the biological effects and secondary metabolites are addressed. Nepeta species are characterized by terpenoid‐type compounds and phenolic constituents, which exert several activities such as an antimicrobial, repellent against major pathogen vector mosquitoes, insecticide, larvicide against Anopheles stephensi, cytotoxic anticarcinogen, antioxidant, anticonvulsant, analgesic, anti‐inflammatory agent, and antidepressant, revealing its importance in medicinal and agricultural fields. On the basis of numerous studies, the Nepeta genus demonstrates remarkable therapeutic effects against various diseases. However, clinical studies are warranted to confirm preclinical findings.
Mesenchymal Stromal Cell Therapy in Bronchopulmonary Dysplasia: Systematic Review and Meta-Analysis of Preclinical Studies
Authors: Augustine Sajit , Avey Marc T. , Harrison Brittany , Locke Tiffany , Ghannad Mona , Moher David , Thébaud Bernard
Published: October 2017

Extreme prematurity is the leading cause of death among children under 5 years of age. Currently, there is no treatment for bronchopulmonary dysplasia (BPD), the most common complication of extreme prematurity. Experimental studies in animal models of BPD suggest that mesenchymal stromal cells (MSCs) are lung protective. To date, no systematic review and meta-analysis has evaluated the preclinical evidence of this promising therapy. Our protocol was registered with Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies prior to searching MEDLINE (1946 to June 1, 2015), Embase (1947 to 2015 Week 22), Pubmed, Web of Science, and conference proceedings (1990 to present) for controlled comparative studies of neonatal animal models that received MSCs or cell free MSC-derived conditioned media (MSC-CM). Lung alveolarization was the primary outcome. We used random effects models for data analysis and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines. We screened 990 citations; 25 met inclusion criteria. All used hyperoxia-exposed neonatal rodents to model BPD. MSCs significantly improved alveolarization (Standardized mean difference of −1.330, 95% confidence interval [CI −1.724, −0.94, I2 69%]), irrespective of timing of treatment, source, dose, or route of administration. MSCs also significantly ameliorated pulmonary hypertension, lung inflammation, fibrosis, angiogenesis, and apoptosis. Similarly, MSC-CM significantly improved alveolarization, angiogenesis, and pulmonary artery remodeling. MSCs, tested exclusively in hyperoxic rodent models of BPD, show significant therapeutic benefit. Unclear risk of bias and incomplete reporting in the primary studies highlights nonadherence to reporting standards. Overall, safety and efficacy in other species/large animal models may provide useful information for guiding the design of clinical trials.
An overview of emerging pattern mining in supervised descriptive rule discovery: taxonomy, empirical study, trends, and prospects
Authors: García‐Vico A.M. , Carmona C.J. , Martín D. , García‐Borroto M. , del Jesus M.J.
Published: October 2017

Emerging pattern mining is a data mining task that aims to discover discriminative patterns, which can describe emerging behavior with respect to a property of interest. In recent years, the description of datasets has become an interesting field due to the easy acquisition of knowledge by the experts. In this review, we will focus on the descriptive point of view of the task. We collect the existing approaches that have been proposed in the literature and group them together in a taxonomy in order to obtain a general vision of the task. A complete empirical study demonstrates the suitability of the approaches presented. This review also presents future trends and emerging prospects within pattern mining and the benefits of knowledge extracted from emerging patterns. WIREs Data Mining Knowl Discov 2018, 8:e1231. doi: 10.1002/widm.1231

This article is categorized under:

Fundamental Concepts of Data and Knowledge > Knowledge Representation

Fundamental Concepts of Data and Knowledge > Motivation and Emergence of Data Mining
Impact of Critical Illness Polyneuromyopathy in Rehabilitation: A Prospective Observational Study
Authors: Cunningham Cameron J.B. , Finlayson Heather C. , Henderson William R. , O'Connor Russell J. , Travlos Andrew
Published: October 2017

Background

Critical illness polyneuromyopathy (CIPNM) increasingly is recognized as a source of disability in patients requiring intensive care unit (ICU) admission. The prevalence and impact of CIPNM on patients in the rehabilitation setting has not been established.

Objectives

To determine the proportion of at‐risk rehabilitation inpatients with evidence of CIPNM and the functional sequelae of this disorder.

Design

Prospective observational study.

Setting

Tertiary academic rehabilitation hospital.

Patients

Rehabilitation inpatients with a history of ICU admission for at least 72 hours.

Methods

Electrodiagnostic studies were performed to evaluate for axonal neuropathy and/or myopathy in at least one upper and one lower limb.

Main Outcome Measurements

The primary outcome was prevalence of CIPNM. Secondary outcomes included Functional Independence Measure (FIM) scores, rehabilitation length of stay (RLOS), and discharge disposition.

Results

A total of 33 participants were enrolled; 70% had evidence of CIPNM. Admission FIM score, discharge FIM, FIM gain, and FIM efficiency were 64.1, 89.9, 25.5, and 0.31 in those with CIPNM versus 78.4, 94.6, 16.1, and 0.33 in those without CIPNM, respectively. Average RLOS was 123 days versus 76 days and discharge to home was 57% versus 90% in the CIPNM and non‐CIPNM groups, respectively.

Conclusions

CIPNM is very common in rehabilitation inpatients with a history of ICU admission. It was associated with a lower functional status at rehabilitation admission, but functional improvement was at a similar rate to those without CIPNM. Longer RLOS stay may be required to achieve the same functional level.

Level of Evidence

III
Aristotle on Religion
Authors: Segev Mor
Published: October 2017

Aristotle is a severe critic of traditional religion, believing it to be false, yet he also holds that traditional religion and its institutions are necessary if any city, including the ideal city he describes in the Politics, is to exist and flourish. This book provides, for the first time, a coherent account of the socio-political role which Aristotle attributes to traditional religion despite his rejection of its content. Mor Segev argues that Aristotle thinks traditional religion is politically necessary because it prepares the ground for what he considers the pinnacle of human endeavor: attaining the knowledge of ﬁrst philosophy, whose objects are real beings worthy of being called gods. Developing this interpretation, Segev goes on to analyze Aristotle's references to the myths of traditional Greek religion, and to assess his influence on medieval Jewish and Christian theology and philosophy of religion.
Algebraic Groups
Authors: Milne J. S.
Published: October 2017

Algebraic groups play much the same role for algebraists as Lie groups play for analysts. This book is the first comprehensive introduction to the theory of algebraic group schemes over fields that includes the structure theory of semisimple algebraic groups, and is written in the language of modern algebraic geometry. The first eight chapters study general algebraic group schemes over a field and culminate in a proof of the Barsotti–Chevalley theorem, realizing every algebraic group as an extension of an abelian variety by an affine group. After a review of the Tannakian philosophy, the author provides short accounts of Lie algebras and finite group schemes. The later chapters treat reductive algebraic groups over arbitrary fields, including the Borel–Chevalley structure theory. Solvable algebraic groups are studied in detail. Prerequisites have also been kept to a minimum so that the book is accessible to non-specialists in algebraic geometry.
Sociological Studies in Roman History
Authors: Hopkins Keith
Published: October 2017

Keith Hopkins was a sociologist and Professor of Ancient History at Cambridge from 1985 to 2001. He is widely recognised as one of the most radical, innovative and influential Roman historians of his generation. This volume presents fourteen of Hopkins' essays on an impressive range of subjects: contraception, demography, economic history, slavery, literacy, imperial power, Roman religion, Early Christianity, and the social and political structures of the ancient world. The papers have been re-edited and revised with accompanying essays by Hopkins' colleagues, friends and former students. This volume brings Hopkins' work up to date. It sets his distinctive and pioneering use of sociological approaches in a wider intellectual context and explores his lasting impact on the ways that ancient history is now written. This volume will interest all those fascinated by Rome and its empire, and particularly those eager to experience challenging and controversial ways of understanding the past.