bluuebunny/crossref_metadata_2025_split huggingface dataset:
PLS multivariate analysis applied to corrosion studies on reinforced concrete
Authors: Monzón Pablo , Ramón José Enrique , Gandía‐Romero José Manuel , Valcuende Manuel , Soto Juan , Palací‐López Daniel 
Published: November 2018

AbstractThere are few techniques available to calculate the corrosion rate (icorr) of reinforcing steel in concrete structures. This is due not only to a lack of instrumentation but also because it is necessary to take into account that polarization can irreversibly modify the metal surface and can affect the results or the future state of the metal. This is the reason some researchers prefer to test reinforcing steel with reversible techniques. The main objective of this study is to predict the corrosion rate of reinforced concrete using electrochemical methods combined with statistical tools such as multivariate analysis. Using reinforcements embedded in mortar samples, the corrosion rates were determined at different ages using the Tafel method, and values obtained were compared with other techniques: linear polarization resistance (LPR), potentiostatic pulse testing (PPT), and AC electrochemical impedance spectroscopy (EIS). In addition, these values were compared to those obtained using a mixed technique based on partial least squares (PLS). With this technique, we were able to automatically analyze the current data obtained from LPR, PPT, and EIS and to predict the icorr value. The study allows us to conclude that it is possible to obtain reliable icorr values, very close to those obtained with the Tafel method by using PLS combined with PPT or LPR. Furthermore, it presents several advantages, such as being able to directly treat data without requiring an established Stern‐Geary constant (B) for LPR and not having to use an equivalent circuit (EC) in EIS to calculate icorr because only the impedance spectra are necessary.
Synthesis of μ2‐Oxo‐Bridged Iron(III) Tetraphenylporphyrin–Spacer–Nitroxide Dimers and their Structural and Dynamics Characterization by using EPR and MD Simulations
Authors: Abdullin Dinar , Fleck Nico , Klein Christoph , Brehm Philipp , Spicher Sebastian , Lützen Arne , Grimme Stefan , Schiemann Olav 
Published: November 2018

AbstractIron(III) porphyrins have the propensity to form μ2‐oxo‐dimers, the structures of which resemble two wheels on an axle. Whereas their crystal structure is known, their solution structure and internal dynamics is not. In the present work, the structure and dynamics of such dimers were studied by means of electron paramagnetic resonance (EPR) spectroscopy and quantum chemistry based molecular dynamics (MD) simulations by using the semiempirical tight‐binding method (GFN‐xTB). To enable EPR investigation of the dimers, a nitroxide was attached to each of the tetraphenylporphyrin cores through a linear and a bent linker. The inter‐nitroxide distance distributions within the dimers were determined by continuous‐wave (cw)‐EPR and pulsed electron–electron double resonance (PELDOR or DEER) experiments and, with the help of MD, interpreted in terms of the rotation of the porphyrin planes with respect to each other around the Fe–O–Fe axis. It was found that such rotation is restricted to the four registers defined by the phenyl substituents. Within the registers, the rotation angle swings between 30° and 60° in the proximal and between 125° and 145° in the distal register. With EPR, all four angles were found to be equally populated, whereas the 30° and 145° angles are strongly favored to the expense of the 60° and 125° angles in the MD simulation. In either case, the internal dynamics of these dimers thus resemble the motion of a step motor.
A Hexavalent Basket for Bottom‐Up Construction of Functional Soft Materials and Polyvalent Drugs through a “Click” Reaction
Authors: Neal Taylor A. , Wang Weikun , Zhiquan Lei , Peng Ruojing , Soni Priti , Xie Han , Badjić Jovica D. 
Published: November 2018

AbstractInspired by polyvalency and its prevalence in nature, we developed an efficient synthetic route for accessing a large variety of multivalent and dual‐cavity baskets from inexpensive and abundant starting materials. First, the cycloaddition of vinyl acetate to anthracene was optimized to, upon hydrolysis, give dibenzobarrelene derivative 6, which after five functional group transformations and then cyclotrimerization gave heptiptycene dodecaester 4 in an overall 17 % yield. Following that, compound 4 was converted into D3h symmetric 1, composed of two fused cavitands each holding three terminal alkynes at the rim for conjugation to functional molecules using the highly efficient CuAAC reaction. To survey the reactivity of hexavalent 1, we “clicked” 2‐acetamido‐2‐deoxy‐β‐d‐glucopyranosyl azide 3,4,6‐triacetate (carbohydrate), methoxypolyethylene glycol azide (PEG, Mn=2000; polymer) and benzyl azide (aromatic) to obtain hexavalent conjugates 12–14 in 50–79 % yields. In summary, dual‐cavity 1 is an accessible, structurally‐unique and hexavalent host that can be “clicked” to a variety of functional molecules for (a) combinatorial lead identification of drugs, (b) preparation of hierarchical soft materials and (c) design of selective chemosensors, scavengers, or supramolecular catalysts.
Reversible Carbene Insertion into a Ge−N Bond and Insights into CO and Carbene Substitution Reactions Involving Amidinatogermylenes and Fischer Carbene Complexes
Authors: Álvarez‐Rodríguez Lucía , Cabeza Javier A. , García‐Álvarez Pablo , Gómez‐Gallego Mar , González‐Álvarez Laura , Merinero Alba D. , Sierra Miguel A. 
Published: November 2018

AbstractThe formation of the five‐membered‐ring germylene complexes [M(CO)5{Ge(tBu2bzamC(OEt)Me)tBu}] (3M; M=Cr, W), which occurs readily at room temperature from the germylene Ge(tBu2bzam)tBu (1tBu) and Fischer carbenes [M(CO)5{C(OEt)Me}] (2M; M=Cr, W), has been found to be reversible. Upon heating at 60 °C, complexes 3M undergo epimerization to an equilibrium mixture of 3M and 3′M. At that temperature, the chromium epimers (but not the tungsten ones) release CO to end in the mixed germylene–Fischer carbene complexes [Cr(CO)4{C(OEt)Me}{Ge(tBu2bzam)tBu}] (cis‐4Cr and trans‐4Cr). The latter decompose at 120 °C to [Cr(CO)5{Ge(tBu2bzam)tBu}] (6Cr). Because the formation of cis‐4Cr and trans‐4Cr from 3Cr or 3′Cr requires the presence of free 1tBu and 2Cr in the reaction solutions, the reactions of 1tBu with 2M to give 3M (and 3′M at 60 °C) should be reversible. This proposal has been proven by germylene‐exchange crossover reactions in which free 1tBu and [M(CO)5{Ge(tBu2bzamC(OEt)Me)CH2SiMe3}] (5′M; M=Cr, W) were formed when complexes 3M were treated at room temperature with the germylene Ge(tBu2bzam)CH2SiMe3 (1tmsm). A clear differential behavior between N‐heterocyclic carbenes (NHCs) and amidinatogermylenes (1tBu and 1tmsm) in their reactivity against group 6 metal Fischer carbene complexes is demonstrated. The higher electron‐donor capacity of amidinatogermylenes with respect to NHCs and the bias of the former to get involved in ring expansion processes are responsible for this differential behavior.
Diphosphoniodiphosphene Formation by Transition Metal Insertion into a Triphosphenium Zwitterion
Authors: Kosnik Stephanie C. , Binder Justin F. , Nascimento Maxemilian C. , Swidan Ala'aeddeen , Macdonald Charles L. B. 
Published: November 2018

AbstractTreatment of two equivalents of the triphosphenium zwitterion L with sources of Ni0 and Pd0 form the mononuclear η2‐diphosphoniodiphosphene complexes 1 and 2. The reaction between L and [FeCp(CO)2]2 results in the binuclear μ‐η1:η1‐diphosphoniodiphosphene iron complex 3, which features an alternative bonding motif of the diphosphoniodiphosphene unit. The formation of these species has been confirmed by spectroscopic methods and single‐crystal X‐ray diffraction analysis, and their electronic structures have been elucidated using computational methods.
Extended Open‐Chain Polyenides as Versatile Delocalized Anion Ligands for Metal Chain Clusters
Authors: Yamashita Mitsuki , Kawasumi Yuna , Tachibana Yuki , Horiuchi Shinnosuke , Yamamoto Koji , Murahashi Tetsuro 
Published: November 2018

AbstractAlthough small cyclic‐ and open‐chain unsaturated hydrocarbon anions such as cyclopentadienide and open‐chain pentadienide are used as the strongly electron‐donating auxiliary ligands for metal complexes, more extended π‐conjugated unsaturated hydrocarbon anions have rarely been used in coordination chemistry, despite their potential ability to serve as the multiply bridging π‐ligands for metal clusters. This work reports isolation of metal chain clusters bearing the multi‐dentate, open‐chain extended unsaturated hydrocarbon anion ligands. The extended open‐chain π‐conjugated polyenyl ligands could effectively stabilize oxidized palladium chains, including an unprecedented [Pd4]4+ chain.
Absolute configuration and biological profile of pyrazoline enantiomers as MAO inhibitory activity
Authors: Goksen Umut Salgin , Sarigul Sevgi , Bultinck Patrick , Herrebout Wouter , Dogan Ilknur , Yelekci Kemal , Ucar Gulberk , Gokhan Kelekci Nesrin 
Published: November 2018

AbstractA new racemic pyrazoline derivative was synthesized and resolved to its enantiomers using analytic and semipreparative high‐pressure liquid chromatography. The absolute configuration of both fractions was established using vibrational circular dichroism. The in vitro monoamine oxidase (MAO) inhibitory profiles were evaluated for the racemate and both enantiomers separately for the two isoforms of the enzyme. The racemic compound and both enantiomers were found to inhibit hMAO‐A selectively and competitively. In particular, the R enantiomer was detected as an exceptionally potent and a selective MAO‐A inhibitor (Ki = 0.85 × 10−3 ± 0.05 × 10−3 μM and SI: 2.35 × 10−5), whereas S was determined as poorer compound than R in terms of Ki and SI (0.184 ± 0.007 and 0.001). The selectivity of the enantiomers was explained by molecular modeling docking studies based on the PDB enzymatic models of MAO isoforms.
Identifying Terminal Assembly Propensity of Amyloidal Peptides by Scanning Tunneling Microscopy
Authors: Zheng Yongfang , Xu Meng , Yu Lanlan , Qu Fuyang , Lin Yuchen , Xu Jing , Zou Yimin , Yang Yanlian , Wang Chen 
Published: November 2018

AbstractThe abnormal accumulation of beta‐amyloids (Aβ) in brain is considered as a key initiating cause for Alzheimer's disease (AD) due to their richness in plaques and self‐aggregate propensity. In recent studies, N‐terminally extended Aβ peptides (NTE‐Aβ) with the N‐terminus originating prior to the canonical β‐secretase cleavage site were found in humans and suggested to have possible relevance to AD. However, the effects of the extended N‐terminus on the amyloidegenic structure and aggregation propensity have not been fully elucidated. Herein, we characterized the assembly structures of Aβ1‐42, Aβ(−5)‐42, Aβ(−10)–42 and Aβ(−15)‐42 with both normal and reversed sequences on highly oriented pyrolytic graphite (HOPG) surfaces with scanning tunneling microscopy (STM). The molecularly resolved surface‐mediated peptide assemblies enable identification of amyloidegenic fragments. The observations reveal that the assembly propensity of the C‐terminal strand of Aβ1‐42 is highly conserved and insensitive to N‐terminal extensions. In contrast, different assembly structures of the N‐terminal strand of Aβ variants can be observed with possible assignment of varied amyloidegenic fragments in the extended N‐termini, which may contribute to the varied aggregation propensities of Aβ42 species.
Methionine329 in human serum albumin: A novel target for alkylation by sulfur mustard
Authors: Siegert Markus , Gandor Felix , Kranawetvogl Andreas , Börner Hans , Thiermann Horst , John Harald 
Published: November 2018

AbstractExposure to the vesicant sulfur mustard (SM) may lead to erythema and blistering. Toxicity of SM is hypothesized due to the alkylation of DNA bases and nucleophilic amino acid side chains in proteins (adducts) by forming the hydroxyethylthioethyl (HETE) moiety. Despite its prohibition by the chemical weapons convention, SM still represents a serious threat to military personnel and civilians. Therefore, development and improvement of forensic analytical methods for the verification of SM exposure is of high interest. Protein adducts have been shown to be highly suitable and beneficial biomarkers of poisoning. Herein we present methionine329 in human serum albumin (HSA) as a novel target of SM forming a HETE‐methionyl sulfonium ion. The alkylated tetrapeptide LeuGlyMet329(‐HETE)Phe, LGM(‐HETE)F, was detected after pepsin‐mediated proteolysis and subsequent analysis by microbore liquid chromatography–electrospray ionization–high‐resolution tandem‐mass spectrometry. Compound identity was confirmed by a synthetic reference. Proteolysis conditions for HSA were optimized towards maximum yield of LGM(‐HETE)F and its limit of identification (32.3 nM SM in serum) was similar to those of the established HSA‐derived biomarkers HETE‐CysPro and HETE‐CysProPhe (15.6 nM SM in serum). Stability of the alkylated Met329 in vitro and in vivo was limited to 5 days making this modification a beneficial short‐time biomarker. Furthermore, it was found that the HETE‐methionyl sulfonium ion can transfer its HETE moiety to the side chain of cysteine and glutamic acid as well as to the N‐terminus of peptides and proteins in vitro thus revealing novel insights into the molecular toxicity of SM.
Intercontinental migration pattern and genetic differentiation of arctic‐alpine Rhodiola rosea L.: A chloroplast DNA survey
Authors: György Zsuzsanna , Tóth Endre G. , Incze Norbert , Molnár Bence , Höhn Mária 
Published: November 2018

AbstractOur study describes genetic lineages and historical biogeography of Rhodiola rosea a widely distributed arctic‐alpine perennial species of the Northern Hemisphere based on sequence analysis of six chloroplast regions. Specimens of 44 localities from the Northern Hemisphere have been sequenced and compared with those available in the GenBank. Our results support the migration of the species into Europe via the Central Asian highland corridor, reaching the European Alpine System (EAS) and also the western European edge, the British Isles. The EAS proved to be an important center of genetic diversity, especially the region of the Eastern Alps and the Dolomites where signs of glacial refugia was observed. Apart from those of the EAS, a common lineage was detected along the Atlantic coast from the British Isles toward Scandinavia as well as Iceland and the eastern parts of North America. Accordingly, the British Isles represent a main link between the northern Atlantic and southern EAS lineages.
A Bioinspired, Highly Transparent Surface with Dry‐Style Antifogging, Antifrosting, Antifouling, and Moisture Self‐Cleaning Properties
Authors: Feng Chenchen , Zhang Zhiying , Li Juan , Qu Yu , Xing Dandan , Gao Xuefeng , Zhang Zhongyue , Wen Yihao , Ma Yingjun , Ye Jinjin , Sun Runguang 
Published: November 2018

AbstractTransparent coatings with antireflection, antifogging, antifrosting, antifouling, and moisture self‐cleaning properties can dramatically improve the efficiency and convenience of optical elements and thus are highly desirable for practical applications. Here, it is demonstrated that a bionic nanocone surface (BNS) fabricated by a facile, low‐cost process consisting of template‐assisted prepolymer curing followed by surface modification can possess the multiple functions listed above. The polymer coating firmly adheres to a glass substrate due to bonding agents. After SiO2 nanoparticle deposition and low‐surface‐energy fluorosilane modification, the coating shows low microdroplet adhesion. As a result, the as‐prepared BNS exhibits a high transmittance when exposed to fog and good clarity even when the temperature decreases to −20 °C in a humid environment. Dipping the BNS into exemplified graphite powder has almost no influence on the transparency, and the BNS can realize self‐cleaning of moisture when the surface is covered with a thick layer of man‐made contaminants.
Plastic optical fiber respiration sensor based on in‐fiber microholes
Authors: Ahn Dohyun , Park Young June , Shin Jong‐Dug , Lee Jongmin , Park Jaehee 
Published: November 2018

AbstractThis paper presents a novel respiration sensor based on multiple in‐fiber microholes drilled along a plastic optical fiber (POF) that is stitched to a waist‐band wrapped around the patient's abdomen. The bending loss of a POF with a single microhole is analyzed in order to enhance the sensor sensitivity. Several sensors were fabricated using a 1.5 mm‐diameter POF with different numbers and spacing of 0.7 mm‐diameter microholes. The sensitivity of the respiration sensor increased when increasing the number and spacing of the microholes, where the POF respiration sensor with seven 0.7 mm‐diameter in‐fiber microholes spaced at 15 mm showed the highest sensitivity and sufficient strength for respiratory monitoring. Thus, the experimental results confirmed that a POF sensor based on in‐fiber microholes can be effectively used to monitor the respiration of patients.
An objective and subjective quality assessment study of passive gaming video streaming
Authors: Barman Nabajeet , Zadtootaghaj Saman , Schmidt Steven , Martini Maria G. , Möller Sebastian 
Published: November 2018

SummaryPassive gaming video‐streaming applications have recently gained much attention as evident with the rising popularity of many Over The Top (OTT) providers such as Twitch.tv and YouTube Gaming. For the continued success of such services, it is imperative that the user Quality of Experience (QoE) remains high, which is usually assessed using subjective and objective video quality assessment methods. Recent years have seen tremendous advancement in the field of objective video quality assessment (VQA) metrics, with the development of models that can predict the quality of the videos streamed over the Internet. A study on the performance of objective VQA on gaming videos, which are artificial and synthetic and have different streaming requirements than traditionally streamed videos, is still missing. Towards this end, we present in this paper an objective and subjective quality assessment study on gaming videos considering passive streaming applications. Subjective ratings are obtained for 90 stimuli generated by encoding six different video games in multiple resolution‐bitrate pairs. Objective quality performance evaluation considering eight widely used VQA metrics is performed using the subjective test results and on a data set of 24 reference videos and 576 compressed sequences obtained by encoding them in 24 resolution‐bitrate pairs. Our results indicate that Video Multimethod Assessment Fusion (VMAF) predicts subjective video quality ratings the best, while Naturalness Image Quality Evaluator (NIQE) turns out to be a promising alternative as a no‐reference metric in some scenarios.
The effect of infertility‐related stress on Chinese infertile females’ mental health: The moderating role of marital adjustment
Authors: Li Xiaoshan , Wang Kaikai , Huo Yafen , Zhou Mingjie 
Published: November 2018

AbstractAlthough the impacts of infertility‐related stress on mental health have been testified in the literature, the underlying mechanism between them is still not clear. In response to this issue, 286 Chinese women who were pursuing medical treatment for fertility problems in two state‐owned hospitals were invited to complete the survey, including the 7‐item Dyadic Adjustment Scale (DAS), the Fertility Problem Inventory (FPI), the 5‐item Mental Health Inventory (MHI‐5), and demographic variables (e.g., age). The multiple linear regression method (SPSS 16) was used to investigate the impact of infertility‐related stress and marital satisfaction on infertile women's mental health. Results showed that the total FPI score—and the specific domains of Social Concern, Relationship Concern, and Rejection of Child‐Free Lifestyle in particular—had a significant negative relation with infertile women's mental health and marital satisfaction as a moderator between them. Therefore, the core of marital relationship and specific infertility‐related stress should be addressed in psychological intervention programs for people facing infertility in mainland China.
Homework Goal Orientation Scale: Measurement invariance and latent mean differences across gender and grade level
Authors: Sun Meilu , Du Jianxia , Xu Jianzhong , Liu Fangtong 
Published: November 2018

AbstractThe current study validated the Homework Goal Orientation Scale (HGOS) for secondary school students. Results revealed that HGOS consisted of two distinct but related subscales: mastery‐approach and performance‐approach. Given satisfactory measurement invariance, the latent mean differences were then examined across gender (males vs. females) and grade level (7th vs. 9th). Findings showed no statistically significant mean differences across gender and grade level. Finally, consistent with theoretical expectations, compared with performance‐approach, mastery‐approach was more strongly associated with homework effort, homework emotion regulation, homework completion, and math achievement.
Oncologist recommendation matters!—Predictors of psycho‐oncological service uptake in oncology outpatients
Authors: Frey Nascimento Antje , Tondorf Theresa , Rothschild Sacha I. , Koller Michael T. , Rochlitz Christoph , Kiss Alexander , Schaefert Rainer M. , Meinlschmidt Gunther P. , Hunziker Sabina , Gaab Jens , Zwahlen Diana 
Published: November 2018

AbstractObjectiveHighly distressed cancer patients often do not use psycho‐oncological services (POS). Research on predictors of POS uptake has mainly focused on patient‐related variables and less on communication variables, so we examined the link between patient‐oncologist communication (ie, talking about psychosocial distress, providing detailed information, and recommending POS) and POS uptake.MethodsWe conducted a prospective, observational study in an Oncology Outpatient Clinic in Switzerland. Predictors (ie, patient‐related variables and patient's reports of the patient‐oncologist communication) were assessed via semistructured interviews, and information on outpatient POS uptake was assessed after 4 months. For statistical analysis, a multivariate logistic regression was performed.ResultsOf 333 participants (mean age 61 years; 55% male; 54% distress thermometer ≥5), 77 (23%) had used POS during a 4‐month period. Patients who reported an oncologist‐recommended POS (odds ratio [OR] = 6.27, 95% confidence interval [CI] = 3.14‐12.85) and those who were not sure if they had received a recommendation (OR = 4.64, 95% CI = 1.83‐11.97) were more likely to attend POS than those who reported receiving no recommendation. Talking about psychosocial distress (OR = 0.74, 95% CI = 0.38‐1.46) and providing detailed information about POS did not predict POS uptake (OR = 1.06, 95% CI = 0.46‐2.38).ConclusionsOncologists' expert recommendations to attend POS were strongly associated with patients' uptake of POS. The central role played by oncologists should be accounted for in stepped psycho‐oncological care when POS referral pathways are defined.