bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of gamma‐ray radiation effects on series of bisphthalonitrile resins: Thermomechanical, mechanical, and thermal properties
Authors: Dayo Abdul Qadeer , Zhang Li‐li , Wang Jun , Liu Wen‐bin , Kiran Sadia , Zegaoui Abdeldjalil , Ghouti Hamid Abdelhafid , Arse Yitagesu Bereket
Published: July 2019

The bisphthalonitrile (PN) thermosets series (poly(Baph), poly(Bafph), and poly(Bzph)) were prepared and subjected to 100 and 500 kGy γ‐ray irradiation dose from cobalt‐60 (60Co) as a source. The main objective of this present study was to investigate the effects of gamma irradiation on the chemical structure, thermomechanical, mechanical, and thermal stabilities, which were studied by using a Fourier transform infrared (FTIR), dynamic mechanical analysis, bending test, and thermogravimetric analysis, respectively. The PN resins characteristics bands, namely, nitrile, triazine ring, and phthalocyanine, were not affected on γ‐ray irradiation. However, remarkable changes were observed in the chemical structures of benzene, alkyl and CF3, which indeed slightly declined the thermal stabilities, thermomechanical and flexural properties. The decrease in properties could be ascribed to the scission of molecular chains and rupture of chemical bonds of PN resin as confirmed by the FTIR. The poly(Bafph) showed a maximum decline in the thermal stabilities and mechanical properties due to the existence of CF3in the polymer skeleton, which could not be crosslinked again once scission occurs under radiation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 48313.
4,4′‐Methylenebis(2,6‐di‐t‐butylphenol) as filler in high‐damping chlorinated polyethylene composites
Authors: Fu Bohan , Jiang Sheng , Zhang Tonghua
Published: July 2019

Damping materials are widely used in the modern industry as a kind of material for reducing vibration. The high‐damping composites consisting of chlorinated polyethylene (CPE) and 4,4′‐Methylenebis(2,6‐di‐t‐butylphenol) (AO‐4426) were successfully prepared in this work. The microstructural and mechanical properties of the CPE/AO‐4426 composites were systematically investigated by using SEM, DSC, FTIR, and DMA. From the SEM, most of hindered phenol was dissolved in the CPE matrix and formed a fine dispersion. The results of DSC and FTIR suggested that strong intermolecular interaction like the hydrogen bonding was formed between the AO‐4426 and CPE. It was found that with the increase of AO‐4426 content, a new transition appeared above the glass transition temperature of the CPE matrix, with higher glass transition temperature and higher tan δ value than the neat CPE. As expected, the hybrid displayed excellent performance and had exciting potential applications as a damping material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48321.
Hands on: Information Experiences as Sources of Value
Authors: Rusho Yonit , Raban Daphne R.
Published: July 2019

Value perception increases when people engage in producing physical objects. However, information differs from physical objects by being intangible and easy‐to‐copy. Information as an experience good is inherently challenging to evaluate a priori; therefore, comparing value before and after different types of experience is likely to inform theory about users' preferences regarding information. Prior research mostly refers to consuming information and rarely considers the experience of producing information as a factor affecting information value. The current research compares the effect of experiencing online information through production and consumption processes on value perception. In a set of 6 experiments with 178 participants, willingness‐to‐pay by consumers and willingness‐to‐accept payment by producers are measured before and after consumption and production of information, independently and as repeated measures. In the experiments, we define and implement a framework for an information production process. The results show that the value of information is dynamic. Value perception increased after experiencing information, especially when people engaged in producing information compared to consuming it. This study offers a window toward the practical design of new digital information products.
Spontaneous helping behavior of autistic and non‐autistic (Pre‐)adolescents: A matter of motivation?
Authors: O'Connor Rachel A. G. , Stockmann Lex , Rieffe Carolien
Published: July 2019

Young autistic people have a range of social difficulties, but it is not yet clear how these difficulties can be explained. In addition, emerging research is suggesting that autistic girls may differ from boys in terms of their social behaviors, but yet unknown is if they differ in terms of their pro‐social behavior, such as helping. The present study investigated spontaneous helping behavior using an in vivo paradigm and related this to participants' levels of social motivation (based on parent reports). Participants were 233 autistic and non‐autistic (pre‐)adolescents (M = 12.46 years, SD = 15.54 months). Our results demonstrated that autistic girls and boys have lower levels of social motivation compared to their non‐autistic peers, but social motivation was unrelated to helping behavior in both groups. Furthermore, when the experimenter needed help, the autistic boys and girls looked and smiled to the same extent as their peers of the same gender, but they actually helped significantly less than their non‐autistic peers. However, most autistic youngsters did help, highlighting the great individual differences in autistic individuals. We discuss the possibility that lower levels of helping behavior are due to difficulty initiating action in a social context, rather than lower social motivation. Autism Res 2019, 12: 1796–1804. © 2019 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.

Lay Summary

This study examined the helping behavior of autistic boys and girls (aged 9–16). Many autistic young people did help, but compared to non‐autistic individuals, autistic people did not help as much. This study also showed that when people did/did not help, it was not related to their interest in social relationships. It is important to teach young autistic people when and how to help others, to support them making friends.
Electronic nicotine delivery systems and pregnancy: Recent research on perceptions, cessation, and toxicant delivery
Authors: Breland Alison , McCubbin Andrea , Ashford Kristin
Published: July 2019

Electronic nicotine delivery systems (ENDS), which includes e‐cigarettes (ECIGs), are a rapidly‐expanding class of products that heat a liquid (which may or may not contain nicotine) to produce an aerosol. The variation of ECIG components is extensive as are their effects on users. Epidemiological data show that while both adults and youth use ECIGs, use among youth has increased dramatically in recent years. Other epidemiological data show that women of reproductive age and some pregnant women are also using ECIGs. The goal of this article is to provide readers with background information about ECIGs, with a focus on recent findings about ECIG use in pregnancy and potential implications. Among pregnant women, correlates of ECIG use include current cigarette smoking, among other factors. Regarding pregnant women's perceptions of ECIG use in pregnancy, two themes emerge from the literature: many pregnant women perceive ECIGs to be safer than conventional cigarettes, and that ECIGs can aid with smoking cessation. In contrast to these perceptions, there is little concrete evidence that ECIGs help smokers quit. In addition, there are concerns about ECIG nicotine and other toxicant delivery. Nicotine is a toxicant of particular concern for pregnant women, as nicotine is known to harm a developing fetus. There are many limitations to existing research, and the literature is scant in this area. Further, new “pod mod”‐style ECIGs such as JUUL present new challenges. Overall, with limited evidence of their effectiveness, and concerns about developmental toxicology, the authors do not recommend that pregnant women use ECIGs.
Characterization of the Site‐Specific Acid‐Base Equilibria of 3‐Nitrotyrosine
Authors: Pálla Tamás , Fogarasi Erzsébet , Noszál Béla , Tóth Gergő
Published: July 2019

The complete macro‐ and microequilibrium analyses of 3‐nitrotyrosine, a biomarker of oxidative stress damage, are presented for the first time. The protonation macroconstants were determined by 1H‐NMR‐pH titration, while microconstants were elucidated by a combination of deductive and NMR methods, in which properties of the methyl ester derivative as an auxiliary compound were also studied. Combination of the NMR‐pH characterization of the title and auxiliary compounds and the pair‐interactivity parameters of 3‐iodotyrosine provided the sufficient system to evaluate all the microconstants. NMR‐pH profiles, macroscopic and microscopic protonation schemes, and species‐specific distribution diagrams are included. The phenolate basicity of 3‐nitrotyrosine is 500 times below that of tyrosine, and it is even lower than that of 3‐iodotyrosine. This phenomenon can be explained by the stronger electron withdrawing and the negative mesomeric effect of the nitro group. Based on our results, 89 % of the phenolic OH groups are deprotonated in 3‐NT molecules at the pH of the blood plasma.
Characterization of Hierarchical Porous Carbons Made from Bean Curd via K2CO3 Activation as a Supercapacitor Electrode
Authors: Mu Jiahui , Li Qiang , Kong Xiangjin , Wu Xiaozhong , Sunarso Jaka , Zhao Yi , Zhou Jin , Zhuo Shuping
Published: July 2019

Progress in sustainable energy development often relies upon the idea of making use of green materials and agents to fabricate the components of high‐performance energy storage devices. Herein, we show that a relatively high energy density of 11.9 Wh kg−1 at a 0.1 A g−1 current density in a 1 M H2SO4 solution and a stable capacitance performance for up to 10000 cycles can be achieved in a symmetric supercapacitor (SC) made of two identical hierarchical porous carbon (HPC) electrodes derived from bean curd and 10 wt.% potassium carbonate (K2CO3); both of which are non‐toxic, edible materials. Such HPC, defined as HPC‐10, which was made through a one‐pot activation process followed by carbonization at 750 °C, exhibits high specific surface area of 2514 m2 g−1, hierarchical porous framework (i. e., simultaneous presence of abundant micropores, mesopores, and macropores), and contains N and O dopant components. In a three‐electrode system, HPC‐10 showed specific capacitances of 486 F g−1 in a 1 M H2SO4 and 404 F g−1 in a 6 M KOH, both obtained at a 0.1 A g−1 current density. This work also evaluates systematically the porous structure and electrochemical performance of HPC as a function of K2CO3 concentration from 0 wt.% to 15 wt.%.
Modular Synthesis of DOTA‐Metal‐Based PSMA‐Targeted Imaging Agents for MRI and PET of Prostate Cancer
Authors: Schmitthenner Hans F. , Dobson Damien E. , Jones Kelsea G. , Akporji Nnamdi , Soika Dana Q. M. , Nastiuk Kent L. , Hornak Joseph P.
Published: July 2019

A practical, convergent synthesis of prostate‐specific membrane antigen (PSMA) targeted imaging agents for MRI, PET, and SPECT of prostate cancer has been developed. In this approach, metals chelated to 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA) were placed on the side chains of lysine early in the synthesis to form imaging modules. These are coupled to targeting modules, in this case consisting of the PSMA‐binding urea DCL, bonded to an activated linker. The modular approach to targeted molecular imaging agents (TMIAs) offers distinct advantages. By chelating the MRI contrast metal Gd early, it doubles as a protecting group for DOTA. Standard coupling and deprotection steps may be utilized to assemble the modules into peptides, and the need for tri‐tert‐butyl protection of DOTA requiring removal by strong acid is averted. This enables mild conjugation of the imaging module to a wide variety of targeting agents in the final step. It was further discovered that two labile metals, La3+ or Ce3+, can be used as placeholders in DOTA during the synthesis, then transmetalated in mild acid by Cu2+, Ga3+, In3+, and Y3+, metals used in PET/SPECT. This enables the efficient synthesis of nonradioactive analogues of targeted molecular imaging agents that may be transported or stored until needed. A simple and mild two‐step transmetalation, involving de‐metalation in dilute acid, followed by rapid chelation of the radioactive metal, may be conveniently performed later at the clinic to provide the TMIAs for PET or SPECT.
Efficient manganese decorated cobalt based catalysts for hydrogenation of 5‐hydroxymethylfurfural (HMF) to 2,5‐dimethylfuran (DMF) biofuel
Authors: Akmaz Solmaz , Esen Merve , Sezgin Esra , Koc Serkan Naci
Published: July 2019

2,5‐dimethylfuran (DMF) is a promising compound in the production of biofuel with high‐quality properties. In this study, it is aimed to develop new efficient catalysts to synthesize DMF from 5‐hydroxymethylfurfural (HMF). Co, Mn/Co, and Ru/Co catalysts were prepared using the NaBH4 reduction method. The catalysts were subjected to activity tests for the hydrogenation of HMF to DMF by changing the reaction parameters, such as temperature and time. Mn/Co catalysts prepared from metal precursors at various molar ratios of Mn/Co were found to be effective in hydrogenation reactions of HMF to DMF. A 91.8% DMF yield was achieved in the presence of a Mn/Co (50/50) catalyst without noble metal at 180°C for 4 hours. The Brunauer‐Emmet‐Teller (BET) method, x‐ray diffraction (XRD), x‐ray photoelectron spectroscopy (XPS), and induction coupled plasma mass spectroscopy (ICP‐MS) techniques were used to characterize the efficient Mn/Co catalyst.
A new monitoring method for the between‐mode transition of multimode processes
Authors: Gao Zhenpeng , Jia Mingxing , Mao Zhizhong , Zhao Luping
Published: July 2019

In practical industrial processes, the between‐mode transition commonly exists. It is accepted that the transition has a closer association with its neighbouring modes than with the other modes in the multimode processes. Thus, this paper first separates the subspace based on the relationships between the transition and the features of its neighbouring modes. Then it models the local information of the transition in the remaining subspace. In this way, a complete monitoring structure is set up from cross‐mode and inner‐mode viewpoints. Moreover, the new monitoring method can be applied without special conditions. Both the three tank practical process and the Tennessee Eastman challenge problem have validated the effectiveness of the proposed method.
Synthesis and Preliminary Evaluation of [11C]GNE‐1023 as a Potent PET Probe for Imaging Leucine‐Rich Repeat Kinase 2 (LRRK2) in Parkinson's Disease
Authors: Chen Zhen , Shao Tuo , Gao Wei , Fu Hualong , Collier Thomas Lee , Rong Jian , Deng Xiaoyun , Yu Qingzhen , Zhang Xiaofei , Davenport April T. , Daunais James B. , Wey Hsiao‐Ying , Shao Yihan , Josephson Lee , Qiu Wen‐Wei , Liang Steven
Published: July 2019

Leucine‐rich repeat kinase 2 (LRRK2) is a large protein involved in the pathogenesis of Parkinson's disease (PD). It has been demonstrated that PD is mainly conferred by LRRK2 mutations that bring about increased kinase activity. As a consequence, selective inhibition of LRRK2 may help to recover the normal functions of LRRK2, thereby serving as a promising alternative therapeutic target for PD treatment. The mapping of LRRK2 by positron emission tomography (PET) studies allows a thorough understanding of PD and other LRRK2‐related disorders; it also helps to validate and translate novel LRRK2 inhibitors. However, no LRRK2 PET probes have yet been reported in the primary literature. Herein we present a facile synthesis and preliminary evaluation of [11C]GNE‐1023 as a novel potent PET probe for LRRK2 imaging in PD. [11C]GNE‐1023 was synthesized in good radiochemical yield (10 % non‐decay‐corrected RCY), excellent radiochemical purity (>99 %), and high molar activity (>37 GBq μmol−1). Excellent in vitro binding specificity of [11C]GNE‐1023 toward LRRK2 was demonstrated in cross‐species studies, including rat and nonhuman primate brain tissues by autoradiography experiments. Subsequent whole‐body biodistribution studies indicated limited brain uptake and urinary and hepatobiliary elimination of this radioligand. This study may pave the way for further development of a new generation of LRRK2 PET probes.
Probing In Vivo Structure of Individual mRNA 3′ Isoforms Using Dimethyl Sulfate
Authors: Moqtaderi Zarmik , Geisberg Joseph V.
Published: July 2019

The DMS region extraction and deep sequencing (DREADS) procedure was designed to probe RNA structure in vivo and to link this structural information to specific 3′ isoforms. Growing cells are treated with the alkylating agent dimethyl sulfate (DMS), which enters easily into cells and modifies RNA molecules at solvent‐exposed A and C residues. RNA is isolated, and sequencing libraries are constructed in a manner that preserves the identities of individual mRNA isoforms arising from alternative cleavage/polyadenylation sites. During the cDNA synthesis step of library construction, the progress of reverse transcriptase (RT) is blocked when it encounters a DMS modification on the RNA, leading to disproportionate cDNA termination adjacent to DMS‐modified positions. After paired‐end deep sequencing, the downstream end of each sequenced fragment is mapped to a specific cleavage/poly(A) site representing an individual mRNA 3′ isoform. The upstream mapped end of the sequenced fragment defines where the RT reaction stopped. Over the population of all sequenced fragments derived from a particular isoform, A and C positions that are overrepresented next to the upstream endpoints in the DMS sample (relative to a parallel untreated control) are inferred to have been DMS modified, and hence solvent exposed. This method thus allows in vivo structural information obtained using DMS to be linked to individual mRNA 3′ isoforms. © 2019 by John Wiley & Sons, Inc.
Efficient localization of target in large scale farmland using generalized regression neural network
Authors: Jondhale Satish R. , Deshpande Rajkumar S.
Published: July 2019

Although simple to implement, the traditional trilateration technique is generally associated with significant location estimation errors because of highly nonlinear relationship between Received Signal Strength Indicator (RSSI) and distance. In case of agricultural farmland, there is always noise uncertainty in the RSSI measurements because of signal propagation issues such as NLOS, multipath propagation, and reflection. In the context of such environmental dynamicity, the localization algorithm must be efficient in terms of Localization Accuracy and Execution Speed to provide real‐time performance. The Generalized Regression Neural Network (GRNN) is a noniterative highly parallel neural architecture with the capability to get trained quickly using very few training samples. This paper introduces a range free GRNN localization algorithm as an alternative to the traditional range‐based trilateration technique for a large scale wheat farmland. This paper also presents the modified Optimal Fitted Parametric Exponential Decay Model (OFPEDM)‐based signal path loss model to deal with the issue of environmental dynamicity. The evaluation of localization performance of the trilateration and the proposed GRNN‐based approaches is carried out with the help of Wireless Sensor Network (WSN) using three path loss models, namely, Log Normal Shadow Fading (LNSM), Original OFPEDM, and proposed Modified OFPEDM. For all these implementations, the proposed GRNN algorithm demonstrates superior localization performance (localization accuracy of the order of few centimeters) over traditional trilateration irrespective of nonlinear system dynamics, path loss model, and environmental dynamicity. The execution speed of the proposed algorithm is of the order of few milliseconds.
Effects of contemporary agricultural land cover on Colorado potato beetle genetic differentiation in the Columbia Basin and Central Sands
Authors: Crossley Michael S. , Rondon Silvia I. , Schoville Sean D.
Published: July 2019

Landscape structure, which can be manipulated in agricultural landscapes through crop rotation and modification of field edge habitats, can have important effects on connectivity among local populations of insects. Though crop rotation is known to influence the abundance of Colorado potato beetle (CPB; Leptinotarsa decemlineata Say) in potato (Solanum tuberosum L.) fields each year, whether crop rotation and intervening edge habitat also affect genetic variation among populations is unknown. We investigated the role of landscape configuration and composition in shaping patterns of genetic variation in CPB populations in the Columbia Basin of Oregon and Washington, and the Central Sands of Wisconsin, USA. We compared landscape structure and its potential suitability for dispersal, tested for effects of specific land cover types on genetic differentiation among CPB populations, and examined the relationship between crop rotation distances and genetic diversity. We found higher genetic differentiation between populations separated by low potato land cover, and lower genetic diversity in populations occupying areas with greater crop rotation distances. Importantly, these relationships were only observed in the Columbia Basin, and no other land cover types influenced CPB genetic variation. The lack of signal in Wisconsin may arise as a consequence of greater effective population size and less pronounced genetic drift. Our results suggest that the degree to which host plant land cover connectivity affects CPB genetic variation depends on population size and that power to detect landscape effects on genetic differentiation might be reduced in agricultural insect pest systems.
Structural Features of Mono‐ and Dimetallic Complexes of Palladium Combining Two Types of Aromatic NHC Ligands
Authors: Gonell Sergio , Peris Eduardo , Poyatos Macarena
Published: July 2019

A family of palladium complexes that combine two types of aromatic N‐heterocyclic carbene (NHC) ligands has been prepared starting from dinuclear palladium complexes. Two of the complexes are mono‐metallic and contain a pyrene‐based mono‐NHC and a benzimidazolylidene ligand. The other two are dimetallic and combine a bridging pyrene‐based bis‐NHC ligand with benzimidazolylidene ligands. All new complexes therefore contain two types of NHC ligands that differ in the size of their aromatic backbones coordinated to the same metal center. All complexes have been characterized and the molecular structure of two of them has been confirmed by X‐ray diffraction studies.
A Novel Catalyst‐Free Synthesis of 2,2‐Diaryl Enamides from Stilbenes via a Nitrene Transfer Reaction
Authors: Zhang Yuanyuan , Ye Wenjing , Zhang Hui , Xiao Xiao
Published: July 2019

A novel catalyst‐free nitrene transfer reaction between stilbenes and iminoiodinanes was achieved for the first time, which provides an efficient and environmentally friendly way to access variously substituted 2,2‐diaryl enamides under mild conditions. Mechanistic investigations suggested the reaction proceed via nitrene transfer and aromatic rearrangement with iminoiodinane also acting as a Lewis acid, benefitting the ring‐opening of the aziridine intermediate.
Regioselective Synthesis of 1,4,5‐Trisubstituted‐1,2,3‐Triazoles from Aryl Azides and Enaminones
Authors: De Nino Antonio , Algieri Vincenzo , Tallarida Matteo A. , Costanzo Paola , Pedrón Manuel , Tejero Tomás , Merino Pedro , Maiuolo Loredana
Published: July 2019

A total regioselective synthesis of 1,4,5‐trisubstituted‐1,2,3‐triazoles from aryl azides and enaminones is reported. The use of an ionic liquid in the presence of water and trimethylamine is crucial for the progress of the reaction. The process, consisting of a cascade starting with a water‐promoted 1,3‐dipolar cycloaddition (in agreement with DFT calculations) followed by a base‐promoted retro‐aza‐Michael reaction, shows a completely different reactivity to previously reported base‐promoted reactions between enaminones and sulfonyl azides only leading to disubstituted triazoles. Such reactivity, reported herein, allows preparation of trisubstituted triazoles in a complete regioselective way.
PPh3/Selectfluor‐Mediated Transformation of Carboxylic Acids into Acid Anhydrides and Acyl Fluorides and Its Application in Amide and Ester Synthesis
Authors: Yang Zhen , Chen Siwei , Yang Fang , Zhang Chenxi , Dou You , Zhou Qiuju , Yan Yizhe , Tang Lin
Published: July 2019

By taking the advantage of PPh3/Selectfluor system, carboxylic acids are efficiently converted into the pivotal intermediates acyloxyphosphonium ions that can selectively react with a second carboxylic acid or fluoride to in situ yield the corresponding acid anhydrides or acyl fluorides. The developed protocol features commercially availabile reagents, no involvement of base, room temperature conditions, and simple experimental procedure. Additionally, various amides or esters are readily achieved, respectively, with the addition of amines or alcohols.
Antihypertensive effect of giant embryo brown rice and pre‐germinated giant embryo brown rice on spontaneously hypertensive rats
Authors: Zhou Xin , Zhao GuoChao , Sun ShuangYan , Li JianYue
Published: July 2019

“Shangshida NO.5” is a giant embryo mutant resulting from giant embryo gene (GE) dysfunction in “Chao2‐10” rice. Here, we compared the antihypertensive effects of “Chao2‐10” brown rice (C2‐10), “Shangshida NO.5” brown rice (GER), and pre‐germinated “Shangshida NO.5” brown rice (PGER) in spontaneously hypertensive rats (SHR). Male SHR at 6 weeks of age were divided into four groups and were fed with (a) a control diet (control), (b) a 40% C2‐10‐supplemented diet (C2‐10), (c) a 40% GER‐supplemented diet (GER), or (d) a 40% PGER‐supplemented diet (PGER) for 8 weeks, and their physiological and biochemical parameters were measured. The results showed that the C2‐10‐, GER‐, and PGER‐supplemented diets significantly decreased systolic blood pressure (SBP) and diastolic blood pressure (DBP) during the experiment. At the end of the experimental period, the SBP and DBP of the C2‐10, GER, and PGER groups were 7.6, 23.3, and 31.1 mmHg and 9.8, 21.1, and 29 mmHg lower than those in the control group, respectively, suggesting the GER and PGER diets were better able to inhibit blood pressure elevation than the C2‐10 diet. The serum creatinine levels in the C2‐10, GER, and PGER groups and the blood urea nitrogen content in the PGER group were significantly lower than those of the control group, indicating that C2‐10‐, GER‐, and especially PGER‐supplemented diets improved renal function. In addition, the antioxidant activity of the C2‐10 group and especially of the GER and PGER groups also improved. The above results suggest that “Shangshida NO.5” rice, particularly pre‐germinated rice, is a good dietary supplement for preventing the development of hypertension.
Large‐scale white matter network reorganization in posttraumatic stress disorder
Authors: Suo Xueling , Lei Du , Li Wenbin , Chen Fuqin , Niu Running , Kuang Weihong , Huang Xiaoqi , Lui Su , Li Lingjiang , Sweeney John A. , Gong Qiyong
Published: July 2019

Recently, graph theoretical approaches applied to neuroimaging data have advanced understanding of the human brain connectome and its abnormalities in psychiatric disorders. However, little is known about the topological organization of brain white matter networks in posttraumatic stress disorder (PTSD). Seventy‐six patients with PTSD and 76 age, gender, and years of education‐matched trauma‐exposed controls were studied after the 2008 Sichuan earthquake using diffusion tensor imaging and graph theoretical approaches. Topological properties of brain networks including global and nodal measurements and modularity were analyzed. At the global level, patients showed lower clustering coefficient (p = .016) and normalized characteristic path length (p = .035) compared with controls. At the nodal level, increased nodal centralities in left middle frontal gyrus, superior and inferior temporal gyrus and right inferior occipital gyrus were observed (p < .05, corrected for false‐discovery rate). Modularity analysis revealed that PTSD patients had significantly increased inter‐modular connections in the fronto‐parietal module, fronto‐striato‐temporal module, and visual and default mode modules. These findings indicate a PTSD‐related shift of white matter network topology toward randomization. This pattern was characterized by an increased global network integration, reflected by increased inter‐modular connections with increased nodal centralities involving fronto‐temporo‐occipital regions. This study suggests that extremely stressful life experiences, when they lead to PTSD, are associated with large‐scale brain white matter network topological reconfiguration at global, nodal, and modular levels.
Designable nanoplasmonic biomarkers for direct microscopy cytopathology diagnostics
Authors: Wang Lu , Darviot Cecile , Zapata‐Farfan Jennyfer , Patskovsky Sergiy , Trudel Dominique , Meunier Michel
Published: July 2019

Direct microscopy interpretation of fine‐needle biopsy cytological samples is routinely used by practicing cytopathologists. Adding possibility to identify selective and multiplexed biomarkers on the same samples and with the same microscopy technique can greatly improve diagnostic accuracy. In this article, we propose to use biomarkers based on designable plasmonic nanoparticles (NPs) with unique optical properties and excellent chemical stability that can satisfy the above‐mentioned requirements. By finely controlling the size and composition of gold‐silver alloy NPs and gold nanorods, the NPs plasmonic resonance properties, such as scattering efficiency and resonance peak spectral position, are adjusted in order to provide reliable identification and chromatic differentiation by conventional direct microscopy. Efficient darkfield NPs imaging is performed by using a novel circular side illumination adaptor that can be easily integrated into any microscopy setup while preserving standard cytopathology visualization method. The efficiency of the proposed technology for fast visual detection and differentiation of three spectrally distinct NP‐markers is demonstrated in different working media, thus confirming the potential application in conventional cytology preparations. It is worth emphasizing that the presented technology does not interfere with standard visualization with immunohistochemical staining, but should rather be considered as a second imaging modality to confirm the diagnostics.
Differentiating Parkinson's disease motor subtypes using automated volume‐based morphometry incorporating white matter and deep gray nuclear lesion load
Authors: Fang Eric , Ann Chu Ning , Maréchal Bénédicte , Lim Jie Xin , Tan Shawn Yan Zhi , Li Huihua , Gan Julian , Tan Eng King , Chan Ling Ling
Published: July 2019

Background

Periventricular leukoaraiosis may be an important pathological change in postural instability gait disorder (PIGD), a motor subtype of Parkinson's disease (PD). Clinical diagnosis of PIGD may be challenging for the general neurologist.

Purpose

To evaluate 1) the utility of a fully automated volume‐based morphometry (Vol‐BM) in characterizing imaging diagnostic markers in PD and PIGD, including, 2) novel deep gray nuclear lesion load (GMab), and 3) discriminatory performance of a Vol‐BM model construct in classifying the PIGD subtype.

Study Type

Prospective.

Subjects

In all, 23 PIGD, 21 PD, and 20 age‐matched healthy controls (HC) underwent MRI brain scans and clinical assessments.

Field Strength/Sequence

3.0T, sagittal 3D‐magnetization‐prepared rapid gradient echo (MPRAGE), and fluid‐attenuated inversion recovery imaging (FLAIR) sequences.

Assessment

Clinical assessment was conducted by a movement disorder neurologist. The MR brain images were then segmented using an automated multimodal Vol‐BM algorithm (MorphoBox) and reviewed by two authors independently.

Statistical Testing

Brain segmentation and clinical parameter differences and dependence were assessed using analysis of variance (ANOVA) and regression analysis, respectively. Logistic regression was performed to differentiate PIGD from PD, and discriminative reliability was evaluated using receiver operating characteristic (ROC) analysis.

Results

Significantly higher white matter lesion load (WMab) (P < 0.01), caudate GMab (P < 0.05), and lateral and third ventricular (P < 0.05) volumetry were found in PIGD, compared with PD and HC. WMab, caudate and putamen GMab, and caudate, lateral, and third ventricular volumetry showed significant coefficients (P < 0.005) in linear regressions with balance and gait assessments in both patient groups. A model incorporating WMab, caudate GMab, and caudate GM discriminated PIGD from PD and HC with a sensitivity = 0.83 and specificity = 0.76 (AUC = 0.84).

Data Conclusion

Fast, unbiased quantification of microstructural brain changes in PD and PIGD is feasible using automated Vol‐BM. Composite lesion load in the white matter and caudate, and caudate volumetry discriminated PIGD from PD and HC, and showed potential in classification of these disorders using supervised machine learning.

Level of Evidence: 1

Technical Efficacy: Stage 1

J. Magn. Reson. Imaging 2020;51:748–756.
A remark on the stability of the HIE‐FDTD implementation of graphene dispersion based on the flux density D‐E and the current density J‐E constitutive relations
Authors: Ramadan Omar
Published: July 2019

Recently, the stability of the hybrid implicit‐explicit finite difference time domain (HIE‐FDTD) implementation of graphene dispersion, based on the current density J‐E constitutive relation, has been studied by N. Xu, J. Chen, and J. Wang (Int J Numer Model. 2018; e2536). It has been shown that the introduced J‐E implementation retains the standard HIE‐FDTD stability constraint. In their study, it is also reported that the stability stringent of the flux density D‐E HIE‐FDTD implementation, which was found in a previous study, is due the derivations of the field's updating equations. In this communication, it is shown that by using the bilinear
‐transformation technique, the stability of the D‐E HIE‐FDTD implementation can also lead to the standard HIE‐FDTD stability constraint. Therefore, the stability limitation of the HIE‐FDTD implementation of the graphene dispersion does not based on the constitutive relation being used but on the employed discretization methodology. Finally, a three‐dimensional (3‐D) numerical test that investigates the graphene layer transmission coefficient is included to validate the accuracy of the given implementation.
Influence of virtual objects' shadows and lighting coherence on distance perception in optical see‐through augmented reality
Authors: Gao Yuan , Peillard Etienne , Normand Jean‐Marie , Moreau Guillaume , Liu Yue , Wang Yongtian
Published: July 2019

This paper focuses on how virtual objects' shadows as well as differences in alignment between virtual and real lighting influence distance perception in optical see‐through (OST) augmented reality (AR). Four hypotheses are proposed: (H1) Participants underestimate distances in OST AR; (H2) Virtual objects' shadows improve distance judgment accuracy in OST AR; (H3) Shadows with different realism levels have different influence on distance perception in OST AR; (H4) Different levels of lighting misalignment between real and virtual lights have different influence on distance perception in OST AR scenes. Two experiments were designed with an OST head mounted display (HMD), the Microsoft HoloLens. Participants had to match the position of a virtual object displayed in the OST‐HMD with a real target. Distance judgment accuracy was recorded under the different shadows and lighting conditions. The results validate hypotheses H2 and H4 but surprisingly showed no impact of the shape of virtual shadows on distance judgment accuracy thus rejecting hypothesis H3. Regarding hypothesis H1, we detected a trend toward underestimation; given the high variance of the data, more experiments are needed to confirm this result. Moreover, the study also reveals that perceived distance errors and completion time of trials increase along with targets' distance.
Polyhedral Oligomeric Silsesquioxane Hybrid Polymers: Well‐Defined Architectural Design and Potential Functional Applications
Authors: Chen Fang , Lin Feng , Zhang Qi , Cai Rong , Wu Yadong , Ma Xiaoyan
Published: July 2019

Polyhedral oligomeric silsesquioxane (POSS)‐hybrid polymers have been successfully employed as functional inorganic–organic hybrid materials for various applications due to their well‐determined structures. The past 6 years has witnessed growing interest in the rational design and synthetic approaches for POSS‐hybrid polymers, driven by the adoption of controlled living radial polymerization and click chemistry. This review addresses developments in the precise manipulation of POSS building blocks via atom transfer radical polymerization, reversible addition–fragmentation chain transfer, and click chemistry. Not only are the structures of POSS‐hybrid polymers tunable in terms of chemical composition, molecular weight, and polydispersity, but they are also controllable in sequential and hierarchical chain topology. Finally, some representative cutting‐edge applications of POSS‐hybrid polymers, including biomedical and energy‐related materials, fabrication of nanostructures, and functional surface coating materials, are highlighted.
ARID1A‐SIN3A drives retinoic acid‐induced neuroblastoma differentiation by transcriptional repression of TERT
Authors: Bui Chi‐Bao , Le Hoa Kim , Vu Diem My , Truong Kieu‐Diem Dinh , Nguyen Nhat Manh , Ho Minh Anh Nguyen , Truong Dinh Quang
Published: July 2019

Aggressive, high‐risk neuroblastoma (NB) exhibits an immature differentiation state, profound epigenetic dysregulation and high telomerase activity. It has been suggested that aggressive NB may be treatable by inducing differentiation whereas therapeutic targeting of telomerase is under investigation for multiple cancer types. While epigenetic regulation of the telomerase reverse transcriptase (TERT) promoter has been described in high‐risk NB, the exact molecular mechanisms are still not completely understood. Here we used quantitative real‐time polymerase chain reaction (PCR), chromatin immunoprecipitation qPCR, quantitative telomeric repeat amplification protocol, and immunoblot techniques to investigate epigenetic regulation of TERT in wild‐type and genetically modified NB cell lines. We demonstrated that TERT expression is reduced during 13‐cis retinoic acid‐induced NB differentiation and that this inversely correlated with increased expression of AT‐rich interaction domain 1A (ARID1A), a subunit of the SWItch/sucrose nonfermentable chromatin remodeling complex. We showed that ARID1A directly caused suppression of TERT and was reliant on DNA binding and co‐occupancy of the TERT promoter by the SIN3 transcription regulator family member A (SIN3A) repressor complex allowing NB differentiation to proceed. Finally, using data from NB patient cohorts, we reported a significant correlation between low ARID1A expression, elevated expression of TERT, and poorly differentiated, high‐risk NB. These results provide insights into a key epigenetic pathway responsible for modulating TERT‐driven NB progression, which could represent a target for therapeutic intervention.
Molecular investigation in Chinese patients with primary carnitine deficiency
Authors: Zhang Yanghui , Li Haoxian , Liu Jing , Yan Huiming , Liu Qin , Wei Xianda , Xi Hui , Jia Zhengjun , Wu Lingqian , Wang Hua
Published: July 2019

Background

Primary carnitine deficiency (PCD) is an autosomal recessive disorder of carnitine transportation caused by mutations in the SLC22A5 that lead to low serum carnitine levels and decreased intracellular carnitine accumulation. Characteristic clinical findings are hypoketotic hypoglycemia and skeletal and cardiac myopathy.

Objective

To genetically diagnose 24 unrelated Chinese patients with PCD, including 18 infants and six adults.

Methods

The entire coding region and the intron–exon boundaries of SLC22A5 were amplified by polymerase chain reaction (PCR). In silico analyses and reverse transcription‐polymerase chain reaction (RT‐PCR) were used to predict variants’ impact on protein structure and function.

Results

Disease‐causing variants in the SLC22A5 were identified in all 24 subjects, and c.288delG, c.495C>A, c.774_775insTCG, c.824+1G>A, and c.1418G>T were novel. The novel variant c.824+1G>A caused a truncated protein p.Phe276Tyrfs*8.

Conclusions

We identified 13 variants in the SLC22A5 in 24 PCD patients, and five of these variants are novel mutations. c.824+1G>A was confirmed to alter mRNA splicing by reverse transcription PCR. Furthermore, our findings broaden the mutation spectrum of SLC22A5 and the understanding of the diverse and variable effects of PCD variants.
Enhanced flocculation activity of polyacrylamide‐based flocculant for purification of industrial wastewater
Authors: Daifa Mahran , Shmoeli Eliyahu , Domb Abraham J.
Published: July 2019

The flocculation activity of commercially available anionic poly (acrylamide‐co‐acrylic acid), p (AAm‐co‐AA) has been significantly improved, without any inorganic coagulant aid. The effect of three types of surfactants, anionic sodium lauryl ether sulfate (SLES) (Palm Epimen), nonionic cocamide DEA, zwitterionic amphoteric Amphotensid B5, and one organic cation, trimethylammonium bromide (TAB) on coagulation/flocculation performance have been investigated. The performance has been analysed in terms of turbidity, total suspended solid (TSS), total iron (TI) content, and BTEX for treating two kinds of industrial wastewater, produced water (PW) and starch water. We have shown that adding a small amount of each of the studied surfactants, and especially cationic TAB, significantly increases the coagulation/flocculation performance without modifying pH levels. A combination of low dosage of flocculant (310 ppb) and TAB (310 ppb), after 5 minutes, presented 88%, 81%, and 62% reduction in turbidity, TSS, and TI content, respectively, whereas by using 5 ppm of flocculant alone (16 times more), only 76%, 75%, and 43% removal was obtained. The results reveal that TAB performs as an efficient coagulant booster. Compared with regular inorganic coagulants, it is more cost‐effective, reduces the consumption of treatment chemicals, and the pH‐dependency of contaminants removal.
Structure design of reinforced honeycomb paperboard core and characterization of its out‐of‐plane bearing strength
Authors: Mou Xin‐ni , Lu Li‐xin
Published: July 2019

Honeycomb paperboard's out‐of‐plane bearing performance is one of the important properties in packaging field application. Further improvement of its bearing performance has important value in engineering practice. In this paper, a honeycomb core structure was designed, and the bonding dimension and manufacturing process were designed. The mechanism of out‐of‐plane quasi‐static compression deformation of reinforced honeycomb paperboard was analyzed by experiments. The theoretical model of out‐of‐plane platform stress was constructed by applying the plastic deformation, plastic energy dissipation and energy conservation theory. The results show that the improved structure can be mechanically bonded in a flat state with less technological changes. Under the same honeycomb core material and core size parameters, the bearing strength of the improved structure increases by an average of 3.9 times to conventional structure. In order to meet the same compressive strength requirement, the improved structure can reduce the performance requirements of honeycomb core material or increase the core size compared with the conventional structure. When the honeycomb core cell is larger, the tension on the core layer required for the production process is reduced. The theoretical and experimental data are in good agreement with each other, and the relative errors are all less than 13%.
External monitoring and returns to hedge fund activist campaigns
Authors: Flugum Ryan , Souther Matthew E.
Published: July 2019

Firms targeted by hedge fund activists experience significantly higher returns when there are fewer external monitors in place at the target firm. Using analyst coverage and institutional ownership as measures of external monitoring presence, we find that low‐monitored activist targets experience abnormal returns 17.52% above that of high‐monitored targets in the 2‐year period following the initial campaign start date. The significant effect of external monitoring remains after controlling for target firm and activist characteristics. We also document improved operating performance and an increased monitoring presence at low‐monitored target firms across the same 2‐year period, consistent with the observed market performance.
Permutations with fixed pattern densities
Authors: Kenyon Richard , Král' Daniel , Radin Charles , Winkler Peter
Published: July 2019

We study scaling limits of random permutations (“permutons”) constrained by having fixed densities of a finite number of patterns. We show that the limit shapes are determined by maximizing entropy over permutons with those constraints. In particular, we compute (exactly or numerically) the limit shapes with fixed 12 density, with fixed 12 and 123 densities, with fixed 12 density and the sum of 123 and 213 densities, and with fixed 123 and 321 densities. In the last case we explore a particular phase transition. To obtain our results, we also provide a description of permutons using a dynamic construction.
Illuminating political clarity in culturally relevant science instruction
Authors: Madkins Tia C. , McKinney de Royston Maxine
Published: July 2019

Failure to improve achievement in K‐12 science for racially minoritized students and students living in poverty continues to challenge the inclusionary rhetoric ofscience for all. Science education researchers, teacher educators, and educators must consider the racialized and classed inequalities that continue to limit students’ opportunities to learn. To achieve this, we must be able to conceptualize sociopolitical pedagogical approaches and learn from empirical examples of science teachers who consciously attend to their students’ realities in empowering rather than deficit‐oriented ways. We argue for the importance of utilizing culturally relevant pedagogy (CRP) and attending to and theorizing an educator's sociopolitical consciousness and enactments of political clarity in science instruction. Our analysis highlights how an African American male science teacher responds to his middle school students’ realities and identities as African American youth and children growing up contexts with limited economic resources. Through classroom observations and interviews with the teacher, we nuance our understanding ofsociopolitical consciousness, the third tenet of CRP, as reliant upon a teacher's political clarity and examine how, through instruction, science teachers can position students and their realities as consonant with knowing and doing science and being scientists.