bluuebunny/crossref_metadata_2025_split huggingface dataset:
Benign Synthesis of Black Microspheres of Anatase TiO2 with Paramagnetic Oxygen Vacancies through NH3 Treatment
Authors: Maqbool Qysar , Srivastava Aasheesh 
Published: August 2017

AbstractColoured TiO2 is coveted for its ability to extract energy from the visible region of electromagnetic spectrum. Here a facile synthesis of black anatase titania microspheres (B‐TiO2) through a two‐step process is reported. In the first step, amorphous white TiO2 microspheres (W‐TiO2) are obtained by hydrolysing titanium tetraisopropoxide by ammonia vapours in ethanol. In the second step, the W‐TiO2 is thermally annealed at 500 °C to obtain B‐TiO2. The diffuse reflectance analysis showed that B‐TiO2 absorbs across visible spectrum with absorption extending well into NIR region. Raman scattering together with EPR analysis showed compelling evidence of the existence of oxygen deficiency within the crystal in B‐TiO2 that induces black colouration in the sample. The defects present in the black anatase sample were confirmed to be single‐electron‐trapped (or paramagnetic) oxygen vacancies (Vo⋅) by XPS and EPR studies. The magnetic susceptibility studies showed existence of antiferromagnetic interactions between these unpaired electron spins.
From a Diphosphanegermylene to Nickel, Palladium, and Platinum Complexes Containing Germyl PGeP Pincer Ligands
Authors: Álvarez‐Rodríguez Lucía , Brugos Javier , Cabeza Javier A. , García‐Álvarez Pablo , Pérez‐Carreño Enrique 
Published: August 2017

AbstractThe PGeP pincer‐type germylene Ge(NCH2PtBu2)C6H4 (1) has been used to prepare a family of group 10 metal complexes, namely, [MCl{κ3P,Ge,P‐GeCl(NCH2PtBu2)2C6H4}] (M=Ni (2Ni), Pd (2Pd), Pt (2Pt)), featuring a chloridogermyl PGeP pincer ligand and a Cl−Ge−M−Cl bond sequence. Their reactivity is not initially centered on the metal atom but on their Ge atom. Complexes 2Ni and 2Pd easily led to the hydrolyzed products [Ni2Cl2{μ‐(κ3P,Ge,P‐Ge(NCH2PtBu2)2C6H4)2O}], which features a Cl−Ni−Ge−O−Ge−Ni−Cl bond sequence, and [PdCl{κ3P,Ge,P‐Ge(OH)(NCH2PtBu2)2C6H4}], which contains a hydroxidogermyl PGeP pincer ligand (2Pt is reluctant to undergo hydrolysis). Simple chloride exchange reactions led to the methoxidogermyl, methylgermyl, and phenylgermyl derivatives [MCl{κ3P,Ge,P‐GeR(NCH2PtBu2)2C6H4}] (M=Pd, Pt; R=OMe, Me, Ph). Whereas the palladium complexes [PdCl{κ3P,Ge,P‐GeR(NCH2PtBu2)2C6H4}] (R=Me, Ph) reacted with more MeLi or PhLi to give palladium black and GeR2(NCH2PtBu2)2C6H4 (R=Me, Ph), similar reactions with the analogous platinum complexes afforded the transmetalation derivatives [PtR{κ3P,Ge,P‐GeR(NCH2PtBu2)2C6H4}] (R=Me, Ph). The short length of the CH2PtBu2 arms of the PGeP pincer ligands forces the metal atoms of all these complexes to be in a very distorted square‐planar ligand environment. The reactivity results have been rationalized with theoretical calculations.
Design, Synthesis, and Characterization of Brequinar Conjugates as Probes to Study DHODH Inhibition
Authors: Madak Joseph T. , Cuthbertson Christine R. , Chen Wenmin , Showalter Hollis D. , Neamati Nouri 
Published: August 2017

AbstractBrequinar, a potent dihydroorotate dehydrogenase (DHODH) inhibitor, has been evaluated in multiple clinical trials as a potential treatment for cancer. To further understand brequinar‐based DHODH inhibition and DHODH′s therapeutic relevance in cancer, we have developed novel brequinar‐based probes. We disclose a 16‐step convergent synthesis of the first brequinar‐PROTAC and a four‐step approach towards the first mitochondrial‐directed brequinar probe. A PROTAC and mitochondria‐directed probe of brequinar both possess cytotoxicity that is superior to brequinar in a colony formation assay.
Unexpected Rotamerism at the Origin of a Chessboard Supramolecular Assembly of Ruthenium Phthalocyanine
Authors: Mattioli Giuseppe , Larciprete Rosanna , Alippi Paola , Bonapasta Aldo Amore , Filippone Francesco , Lacovig Paolo , Lizzit Silvano , Paoletti Anna Maria , Pennesi Giovanna , Ronci Fabio , Zanotti Gloria , Colonna Stefano 
Published: August 2017

AbstractWe have investigated the formation and the properties of ultrathin films of ruthenium phthalocyanine (RuPc)2 vacuum deposited on graphite by scanning tunneling microscopy and synchrotron photoemission spectroscopy measurements, interpreted in close conjunction with ab initio simulations. Thanks to its unique dimeric structure connected by a direct Ru−Ru bond, (RuPc)2 can be found in two stable rotameric forms separated by a low‐energy barrier. Such isomerism leads to a peculiar organization of the molecules in flat, horizontal layers on the graphite surface, characterized by a chessboard‐like alternation of the two rotamers. Moreover, the molecules are vertically connected to form π‐stacked columnar pillars of akin rotamers, compatible with the high conductivity measured in (RuPc)2 powders. Such features yield an unprecedented supramolecular assembly of phthalocyanine films, which could open interesting perspectives toward the realization of new architectures of organic electronic devices.
Locally Excited State–Charge Transfer State Coupled Dyes as Optically Responsive Neuron Firing Probes
Authors: Sirbu Dumitru , Butcher John B. , Waddell Paul G. , Andras Peter , Benniston Andrew C. 
Published: August 2017

AbstractA selection of NIR‐optically responsive neuron probes was produced comprising of a donor julolidyl group connected to a BODIPY core and several different styryl and vinylpyridinyl derived acceptor moieties. The strength of the donor–acceptor interaction was systematically modulated by altering the electron withdrawing nature of the aryl unit. The fluorescence quantum yield was observed to decrease as the electron withdrawing effect of the aryl subunit increased in line with changes of the Hammett parameter. The effectiveness of these fluorophores as optically responsive dyes for neuronal imaging was assessed by measuring the toxicity and signal‐to‐noise ratio (SNR) of each dye. A great improvement of SNR was obtained when compared to the first‐generation BODIPY‐based voltage sensitive dyes with concomitant toxicity decrease. The mechanism for the optical response is disparate from conventional cyanine‐based dyes, opening up a new way to produce effective voltage sensitive dyes that respond well into the NIR region.
Proof of Concept Studies Directed Towards Designed Molecular Wires: Property‐Driven Synthesis of Air and Moisture‐Stable Polystannanes
Authors: Pau Jeffrey , Lough Alan J. , Wylie R. Stephen , Gossage Robert A. , Foucher Daniel A. 
Published: August 2017

AbstractPolystannanes with azobenzene moieties designed to protect the Sn–Sn backbone from light‐ and moisture‐induced degradation are described. The azo‐stannyl precursor 3 (70 %) is converted in good yields (88–91 %) to the mono‐ (4), and dichlorostannanes (5), by sequential chlorination, followed by further reduction of 5 to the dihydride (6) using NaBH4 (78 %). All stannanes were characterised by NMR (1H, 13C, 119Sn) spectroscopy and HRMS; in addition, 3, 4 and 5 were structurally elucidated using X‐ray diffraction analysis. Metal‐free dehydrocoupling of 6 at RT leads exclusively to homopolymer (7‐i) displaying an initial solution 119Sn NMR signal (δ=−196 ppm) that migrates to −235 ppm after 10 days (7‐f). In contrast, metal‐catalyzed dehydrocoupling of 6 in toluene at RT leads directly 7‐f. Random co‐polymers formed from 6 and (nBu)2SnH2 at 4:1 (8 a) and 1:1 (8 b) ratios were compared to the alternating polystannane (9) prepared by the reaction of 6 with (nBu)2Sn(NEt2)2. DFT calculations of 3–6 indicate that hypercoordination at Sn is influenced by substituents and by solvation. Homopolymer 7 was found to have unprecedented moisture and light stability in the solid state for >6 months.
Switching of Reaction Pathway from C−C Rollover to C−N Ring‐Extension Annulation
Authors: Thenarukandiyil Ranjeesh , Dutta Champak , Choudhury Joyanta 
Published: August 2017

AbstractThis work discloses that a simple change in the anion of a copper(II) reagent along with the reaction solvent can dramatically alter the course of a Cp*RhIII‐catalyzed C−H activation–annulation reaction leading to completely switchable chemoselective products. The nature of the anion in terms of its coordinating ability and basicity, and also the polarity of the solvent have been found to be the crucial factors in the observed divergence.
Asymmetric Aminalization via Cation‐Binding Catalysis
Authors: Park Sang Yeon , Liu Yidong , Oh Joong Suk , Kweon Yoo Kyung , Jeong Yong Bok , Duan Mengying , Tan Yu , Lee Ji‐Woong , Yan Hailong , Song Choong Eui 
Published: August 2017

AbstractAsymmetric cation‐binding catalysis, in principle, can generate “chiral” anionic nucleophiles, where the counter cations are coordinated within chiral environments. Nitrogen nucleophiles are intrinsically basic, therefore, its use as nucleophiles is often challenging and limiting the scope of the reaction. Particularly, a formation of configurationally labile aminal centers with alkyl substituents has been a formidable challenge due to the enamine/imine equilibrium of electrophilic substrates. Herein, we report enantioselective nucleophilic addition reactions of potassium phthalimides to Boc‐protected alkyl‐ and aryl‐substituted α‐amido sulfones. In situ generated imines smoothly reacted with the nitrogen nucleophiles to corresponding aminals with good to excellent enantioselectivitiy under mild reaction conditions. In addition, transformation of aminal products gave biologically relevant pyrrolidinone‐fused hexahydropyrimidine scaffold with excellent stereoselectivity and good yield.
Online incipient fault diagnosis based on Kullback‐Leibler divergence and recursive principle component analysis
Authors: Chai Yi , Tao Songbing , Mao Wanbiao , Zhang Ke , Zhu Zhiqin 
Published: August 2017

AbstractFault detection and isolation (FDI) methods based on the principal component analysis (PCA) model have achieved a large number of theoretical studies and applications, especially for complex and highly dimensional processes. However, the Hotelling's T2, that is the most common used statistical distance, can fail in detecting small shifts such as a sensor incipient fault with low fault‐to‐noise ratio (FNR). Although an incipient fault develops slowly, it cannot be ignored and is necessary to be detected early enough to avoid more serious consequences. In this study, a realistic online diagnosis method for incipient faults with low FNR is presented. Based on probability distribution measure, the Kullback‐Leibler divergence (KLD) is utilized to compare the probability density of each of the latent scores to a reference one. Under the hypothesis of Gaussian distribution, dynamic changes of KLDs are computed via the mean and variance of score vectors, which can be updated online utilizing the recursive principal component analysis (RPCA). From simulations, it is shown that the proposed approach can detect, isolate, and estimate the sensor incipient fault of the multivariate AR system successfully.
Application of a screening method for fentanyl and its analogues using UHPLC‐QTOF‐MS with data‐independent acquisition (DIA) in MSE mode and retrospective analysis of authentic forensic blood samples
Authors: Noble Carolina , Weihe Dalsgaard Petur , Stybe Johansen Sys , Linnet Kristian 
Published: August 2017

AbstractThe steady appearance of new fentanyl analogues and the associated overdose deaths require the development of sensitive screening approaches to detect these compounds in biological samples and seizures. We developed a targeted screening method to detect 50 4‐anilidopiperidine‐related fentanyl analogues in whole blood using ultra‐high performance liquid chromatography quadrupole time‐of‐flight mass spectrometry in data‐independent acquisition mode. Sample preparation was performed using protein precipitation on a fully automated robotic setup. Thirteen analogues were selected to validate the method. A small matrix ion enhancement effect (110–123%) was observed for all of the compounds; the recovery ranged from 67% to 81% and the process efficiency from 81% to 98%. Limit of detection was within 0.0005–0.001 mg/kg and limit of identification ranged from 0.001 to 0.005 mg/kg. In the retrospective analysis of 2339 forensic blood samples, the major finding was fentanyl (n = 56), followed by alfentanil (n = 5) and remifentanil (n = 1). Identification of 34 fentanyl analogues was based on the predicted product ions resulting from common fentanyl‐specific collision‐induced cleavages, particularly on the product ion result of the fragmentation on the C‐N bond between the phenylamide moiety and the piperidine ring. The proposed hypothesis was supported by the targeted analysis of 16 fentanyl analogues using this method and available published mass spectral data sources for fentanyl analogues. A targeted screening method for 50 fentanyl analogues was successfully validated and implemented to analyse authentic blood samples, where identifying targeted fentanyl analogues was tentatively achieved without using reference standards.
Effects of Adsorption on Polycyclic Aromatic Hydrocarbon, Lipid Characteristic, Oxidative Stability, and Free Radical Scavenging Capacity of Sesame Oil
Authors: Shi Long‐Kai , Zheng Li , Jin Qing‐Zhe , Wang Xing‐Guo 
Published: August 2017

Treatment with three adsorbents led to reductions of PAHs in sesame oils, and activated carbons are more effective for removal of PAHs than activated clay under the experimental conditions. Fatty acid, triacylglycerol, and γ‐tocopherol profiles of sesame oils are not significantly influenced by addition of any adsorbents. However, significant differences (P < 0.05) are observed in the contents of other minor components, oxidation stability and free radical scavenging capacity between the crude and treated sesame oils. Polyphenol and phytosterol are good predictors of oxidative stability and antioxidant capacity of sesame oils, due to significant correlations are observed. Although adsorption process may bring disadvantage to sesame oils such as reductions of beneficial constituents related to storage stability, free radical scavenging capacity and other physiological functions, however, to eliminate the contamination of PAHs, treatment with activated carbon during sesame oil purification is highly recommended in order to reduce the risk of consumption and to assure the consumer health. Moreover, these results provide a useful guidance for sesame oil plant to improve the quality of the final oil product. Practical Applications: Results of this study can be applied to sesame oil plants and are transferable to other flavor edible oils for which lower the risk of consumption and bring economic and social advantages to manufacturers to guarantee the oil quality and consumer health.In this work, the contents of polycyclic aromatic hydrocarbon, lipid characteristic, oxidative stability, and free radical scavenging capacity of sesame oil during adsorption process are investigated and compared. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed apparent distinctions between the crude and treated sesame oils, thus illustrated that adsorption is a double‐edged sword to sesame oils.
Personalized safety measures reduce the adverse event rate of long‐term video EEG
Authors: Dobesberger Judith , Höfler Julia , Leitinger Markus , Kuchukhidze Giorgi , Zimmermann Georg , Thomschewski Aljoscha , Unterberger Iris , Walser Gerald , Kalss Gudrun , Rohracher Alexandra , Neuray Caroline , Kobulashvili Teia , Höller Yvonne , Trinka Eugen 
Published: August 2017

SummaryObjectiveSafety in epilepsy monitoring units (EMUs) has become an increasing concern because adverse events occur in up to 10% of patients undergoing long‐term video EEG in EMUs. The aim of this study was to assess the effectiveness of a specific safety protocol in an EMU.MethodsWe retrospectively assessed the adverse event rates in a group without (group 1, 84‐month period, Innsbruck, Austria) and a group with (group 2, 33‐month period, Salzburg, Austria) personalized safety measures utilizing a standardized protocol for long‐term epilepsy monitoring in high‐risk patients. Differences in adverse event rates during and after long‐term video EEG between the two groups were calculated and compared.ResultsIn group 1, 44/507 (9%, 95% confidence interval [CI] 6.5–11.5%) patients experienced 53 adverse events: 20/507 (4%, 95% CI 2.6–6.0%) patients had psychiatric events, 15/507 (3%, 95% CI 1.8–4.8%) patients sustained a total of 19 injuries during seizures, and 10/507 (2%, 95% CI 1.1–3.6%) patients had 13 episodes of status epilepticus; one adverse event was treatment‐related (valproic acid–induced encephalopathy; 1/507, 0.2%, 95% CI 0.0–1.1%). By using the new safety protocol in group 2, the adverse event rate was only 5% (95% CI 3.4–7.6%; 30 adverse events in 26/491; 45% reduction; p = 0.036), in contrast. These events included 13 psychiatric complications in 13/491 (2%, 95% CI 1.6–4.5%, p = 0.252) patients, 12 seizure‐related injuries in 9/491 (2%, 95% CI 1.0–3.4%, p = 0.250) patients, and 5 episodes of status epilepticus in 4/491 (1%, 95% CI 0.3–2.1%, p = 0.120) patients.SignificanceImplementation of personalized safety measures in high‐risk patients resulted in a clinically relevant reduction of adverse events in the EMU. Safety protocols are a valid tool to reduce the occurrence of adverse events in EMUs.
The importance of maintenance conditions of Daphnia magna Straus as a test organism for ecotoxicological analysis
Authors: Olkova Anna S. , Kantor Grigorii Y. , Kutyavina Tatyana I. , Ashikhmina Tamara Y. 
Published: August 2017

Abstract

Insufficient attention to the standardization of conditions for test organisms can lead to a distortion of bioassay results by changing the characteristics of the culture. The present study deals with the influence of abiotic factors (temperature of cultivated water, its chemical composition, season of the year) and biotic factors (seeding density) on the culture of Daphnia magna Straus. The natural mortality of D. magna is described by the Gompertz equation. One of the parameters of the equation related to daily increase of mortality is very stable, and we suggest monitoring its constancy as a sign of the health of D. magna culture. Seeding density of crustaceans affects both the fertility of species and their mortality. We observed a high degree of compensation for the natural death of adults with increasing fertility for groups of 10 and 25 species living in 1 L of water; the current population density of D. magna regulates the birth rate of juveniles. If the density is 50 individuals/L, the compensatory effect is reduced. Keeping Daphnia in small groups (for example, 10 individuals) and an increase in temperature from 20 to 25 °C reduces the average life expectancy. Therefore, when choosing a test protocol to determine chronic toxicity, it is important to pay attention to the seeding density of Daphnia, the optimal value being approximately 25 individuals/L. Sensitivity of D. magna depends on the season: it is maximal in winter and minimal in spring and summer. In addition, crustaceans’ sensitivity increases when they are kept in water with low content of natural salts. Environ Toxicol Chem 2018;37:376–384. © 2017 SETAC
Long‐term outcome of 18F‐fluorodeoxyglucose‐positron emission tomography‐guided dose painting for head and neck cancer: Matched case‐control study
Authors: Berwouts Dieter , Madani Indira , Duprez Frédéric , Olteanu AnaMaria Luiza , Vercauteren Tom , Boterberg Tom , Deron Philippe , Bonte Katrien , Huvenne Wouter , De Neve Wilfried , Goethals Ingeborg 
Published: August 2017

AbstractBackgroundThe purpose of this study was to report the long‐term outcome of 18F‐fluorodeoxyglucose‐positron emission tomography (18F‐FDG‐PET)‐guided dose painting for head and neck cancer in comparison to conventional intensity‐modulated radiotherapy (IMRT) in a matched case‐control study.MethodsSeventy‐two patients with nonmetastatic head and neck cancer treated with dose painting were compared with 72 control patients matched on tumor site and T classification. Either 18F‐FDG‐PET‐guided dose painting by contour (DPBC) or voxel intensity‐based dose painting by number (DPBN) was performed; control patients underwent standard IMRT. A total median dose to the dose‐painted target was 70.2‐85.9 Gy/30‐32 fractions versus 69.1 Gy/32 fractions with conventional IMRT. In 31 patients, dose painting was adapted to per‐treatment changes in the tumor and organs‐at‐risk (OAR).ResultsMedian follow‐up in living dose‐painting and control patients was 87.7 months (range 56.1‐119.3) and 64.8 months (range 46.3‐83.4), respectively. Five‐year local control rates in the dose‐painting patients were 82.3% against 73.6% in the control (P = .36); in patients treated to normalized isoeffective doses >91 Gy (NID2Gy) local control reached 85.7% at 5 years against 73.6% in the control group (P =.39). There was no difference in regional (P = .82) and distant control (P = .78). Five‐year overall and disease‐specific survival rates were 36.3% versus 38.1% (P = .50) and 56.5% versus 51.7% (P = .72), respectively. A half of the dose‐painting patients developed acute grade ≥3 dysphagia (P = .004). Late grade 4 mucosal ulcers at the site of dose escalation in 9 of 72 patients was the most common severe toxicity with dose painting versus 3 of 72 patients with conventional IMRT (P = .11). Patients in the dose‐painting group had increased rates of acute and late dysphagia (P = .004 and P = .005).ConclusionDose‐painting strategies can be used to increase dose to specific tumor subvolumes. Five‐year local, regional, and distant control rates are comparable with patients treated with conventional IMRT. Volume and intensity of dose escalation should be further tailored, given the possible increase in severe acute and chronic toxicity. Adapting treatment and decreasing dose to the swallowing structures might contribute to lower toxicity rates when applied in smaller tumor volumes. Whether adaptive DPBN can significantly improve outcomes is currently being investigated in a novel clinical trial.
Benefits of initial CT staging before sentinel lymph node biopsy in patients with head and neck cutaneous melanoma
Authors: Hafström Anna , Silfverschiöld Maria , Persson Simon S. , Kanne Michelle , Ingvar Christian , Wahlberg Peter , Romell Anton , Greiff Lennart 
Published: August 2017

AbstractBackgroundThe value of CT at the time of diagnosis for patients with cutaneous head and neck melanoma clinically asymptomatic for metastatic disease is unclear.MethodsA retrospective medical chart review was performed on 198 consecutive patients identified with primary T1b‐T4b head and neck melanoma clinically asymptomatic for metastatic disease referred for sentinel lymph node biopsy procedures between 2004 and 2014.ResultsInitial CTs identified clinically occult melanoma metastases in 8.1% and advanced second primary tumors in 3.5% of patients. CT findings were false‐negative in 1% and false‐positive in 6% of patients. Overall survival (OS) for patients with true‐positive CT findings was lower than for the other patients (P < .001).ConclusionCT imaging when staging patients with head and neck melanoma seems to identify more metastases than has been reported for melanoma at other sites. Preoperative CTs decreased the number of sentinel lymph node biopsy (SLNBs), thus avoiding the stress and cost of this surgical procedure in 12% of patients.