bluuebunny/crossref_metadata_2025 huggingface dataset:
Organocatalytic and Regiodivergent Mannich Reaction of Ketones with Benzoxazinones
Authors: Viji Mayavan , Sim Jaeuk , Li Siyuan , Lee Heesoon , Oh Kyungsoo , Jung Jae‐Kyung
Published: September 2018

In this study, we have developed solvent‐controlled regioselective Mannich reaction of cyclicimines (benzoxazinones) with various ketones by using ʟ‐proline as catalyst to afford Mannich products in high yields with excellent enantio‐ and diastereoselectivity. The unsymmetrical ketones produced the linear isomer as the major product in chloroform solvent. On contrary, using the DMSO solvent favoured the formation of branch isomer product with excellent enantio‐ and diastereoselectivity. The aromatic auxiliary was successfully removed and afforded N‐protected chiral amino acid derivative.

magnified image
Isobutyl Nitrite‐Mediated Synthesis of Quinoxalines through Double C−H Bond Amination of N‐Aryl Enamines
Authors: Jiao Yan‐Xiao , Wei Lin‐Su , Zhao Chun‐Yang , Wei Kai , Mo Dong‐Liang , Pan Cheng‐Xue , Su Gui‐Fa
Published: September 2018

An efficient and metal‐free double C−H bond amination of N‐aryl enamines using isobutyl nitrite (IBN) has been developed. This method enables the preparation of functionalized quinoxalines in good to excellent yields and tolerates a variety of N‐aryl enamines with diverse functional substituents. Mechanistic studies revealed the presence of a key β‐imino oxime ester intermediate. A quinoxaline derivative could be prepared from β‐carbonyl ester in one‐pot sequence on a gram scale. Finally, two important quinoxaline scaffolds were easily prepared in moderate yields over two steps.

magnified image
The Diverse Reactivity of Disilenes Toward Isocyanides
Authors: Tashkandi Nada Y. , McOnie Sarah L. , Bourque Jeremy L. , Reinhold Crispin R. W. , Baines Kim M.
Published: September 2018

The addition of 2,6‐dimethylphenyl isocyanide andt‐butyl isocyanide to tetramesityldisilene was examined. In both cases, the initially formed product is an iminodisilirane; however, the iminodisiliranes are unstable under the reaction conditions and react with a second equivalent of the isocyanide to give either a 3‐silaazetidine or a novel bicyclic double enamine, respectively. Taken together with the previous examples in the literature, the results demonstrate that subtle differences in the steric bulk of the disilene or the electronic effects of the isocyanide can lead to dramatic differences in the reaction pathway.
Enantioselektive Lewis‐Säure‐katalysierte ortho‐Photocycloaddition von Phenanthren‐9‐carbaldehyden
Authors: Stegbauer Simone , Jandl Christian , Bach Thorsten
Published: September 2018

Die Bestrahlung mit sichtbarem Licht (λ=457 nm) ermöglicht eine enantioselektive ortho‐Photocycloaddition von Olefinen an Phenanthren‐9‐carbaldehyde (15 Beispiele, 46–93 % Ausbeute, 82–98 % ee). Eine chirale Oxazaborolidin‐Lewis‐Säure (20 mol %) wurde als Katalysator verwendet, die durch Koordination an den Aldehyd eine bathochrome Verschiebung der Absorption bewirkt, die über die ursprüngliche nπ*‐Absorption des unkomplexierten Aldehyds hinausgeht. Bei großer Wellenlänge wird ausschließlich der Lewis‐Säure‐Komplex angeregt und eine der beiden enantiotopen Seiten des aromatischen Aldehyds wird effizient abgeschirmt. Die Lewis‐Säure‐Koordination verändert überdies die Typselektivität und die einfache Diastereoselektivität der Photocycloaddition.
Fast Magic‐Angle Spinning 19F NMR Spectroscopy of HIV‐1 Capsid Protein Assemblies
Authors: Wang Mingzhang , Lu Manman , Fritz Matthew P. , Quinn Caitlin M. , Byeon In‐Ja L. , Byeon Chang‐Hyeock , Struppe Jochem , Maas Werner , Gronenborn Angela M. , Polenova Tatyana
Published: September 2018

19F NMR spectroscopy is an attractive and growing area of research with broad applications in biochemistry, chemical biology, medicinal chemistry, and materials science. We have explored fast magic angle spinning (MAS) 19F solid‐state NMR spectroscopy in assemblies of HIV‐1 capsid protein. Tryptophan residues with fluorine substitution at the 5‐position of the indole ring were used as the reporters. The 19F chemical shifts for the five tryptophan residues are distinct, reflecting differences in their local environment. Spin‐diffusion and radio‐frequency‐driven‐recoupling experiments were performed at MAS frequencies of 35 kHz and 40–60 kHz, respectively. Fast MAS frequencies of 40–60 kHz are essential for consistently establishing 19F–19F correlations, yielding interatomic distances of the order of 20 Å. Our results demonstrate the potential of fast MAS 19F NMR spectroscopy for structural analysis in large biological assemblies.
Double‐Helical Nanostructures with Controllable Handedness in Bulk Diblock Copolymers
Authors: Lu Xuemin , Li Jingmin , Zhu Dandan , Xu Min , Li Weihua , Lu Qinghua
Published: September 2018

Double‐helical nanostructures with controllable handedness in bulk materials is of high interest in science and technology for the design and fabrication of new materials, in particular metamaterials, which mimic their natural homologues or even show superior properties. Herein, we report the fabrication of double‐helical structures with controlled handedness through the self‐assembly of an achiral diblock copolymer doped with d‐ and l‐tartaric acid (TA). The helices showed clear handedness dependence on the chirality of the TA. The chiral arrangement of different achiral tectonic units, such as nanoparticles and organic molecules, was confirmed using this helical structure as a template. The double‐helical structure will provide new knowledge for understanding the function of helices, and will enable the application of these systems as chiroptical materials.
Cathode Material Determines Product Selectivity for Electrochemical C−H Functionalization of Biaryl Ketoximes
Authors: Zhao Huai‐Bo , Xu Pin , Song Jinshuai , Xu Hai‐Chao
Published: September 2018

The synthesis of polycyclic N‐heteroaromatic compounds and their corresponding N‐oxides has been developed through electrochemical C−H functionalization of biaryl ketoximes. The oxime substrates undergo dehydrogenative cyclization when a Pt cathode is used, resulting in unprecedented access to a wide range of N‐heteroaromatic N‐oxides. The products of the electrosynthesis are switched to the deoxygenated N‐heteroaromatics by employing a Pb cathode through sequential anode‐promoted dehydrogenative cyclization and cathodic cleavage of the N−O bond in the initially formed N‐oxide.
Supported rhodium liquid metal catalysts for the hydroformylation of olefins
Authors: Sun Hao , Guo Wanwan , Liu Junmei , Feng Zhipeng , Li Ruyue , Zhou Xuyang , Huang Jun
Published: September 2018

The hydroformylation of olefins in supported room temperature liquid metals was developed, and the supported Rh liquid metal catalysts (Rh SLMCs) showed unprecedented activity and high selectivity for the hydroformylation of olefins to aldehydes. The turnover frequency is up to 7000 h−1, much higher than that of homogeneous RhCl3 + 3PPh3 catalyst. Moreover, the Rh SLMCs can be recovered conveniently without obvious deactivation, and the total turnover number is up to 250 000. The active Rh(I) catalyst formed in situ can be reduced back to Rh(0) by the free electrons in liquid metal when H2/CO gas is emitted, and thus Rh is not leaked into the organic solvent. Long‐chain olefins, cycloolefins and styrenes were applied, and the corresponding aldehydes were obtained in good to excellent yields.
Research advances in the synthesis and applications of ferrocene‐based electro and photo responsive materials
Authors: Khan Amin , Wang Li , Yu Haojie , Haroon Muhammad , Ullah Raja Summe , Nazir Ahsan , Elshaarani Tarig , Usman Muhammad , Fahad Shah , Haq Fazal
Published: September 2018

Individually, ferrocene and photochromic materials have several important attributes and applications. Ferrocene is a promising candidate of stimuli‐responsive materials due to its electronic, electrochemical and magnetic properties. On the same lines, photo‐sensitive materials are also an important class of stimuli‐responsive materials which can be modified according to the needs. Recently, a lot of keen attention has been given to the combination of ferrocene with different photo‐sensitive moieties to get novel functional materials. This review illustrates the research advances in the combination of ferrocene‐based small molecules, self‐assembled monolayers and polymers with photo‐responsive compounds and their potential applications.
Three Multicenter, Randomized, Double‐Blind, Placebo‐Controlled Studies Evaluating the Efficacy and Safety of Ustekinumab in Axial Spondyloarthritis
Authors: Deodhar Atul , Gensler Lianne S. , Sieper Joachim , Clark Michael , Calderon Cesar , Wang Yuhua , Zhou Yiying , Leu Jocelyn H. , Campbell Kim , Sweet Kristen , Harrison Diane D. , Hsia Elizabeth C. , van der Heijde Désirée
Published: September 2018

Objective

To evaluate the efficacy and safety of ustekinumab in 3 randomized, placebo‐controlled studies in patients with axial spondyloarthritis (SpA). Studies 1 and 2 included patients with radiographic axial SpA (anti–tumor necrosis factor [anti‐TNF]–naive patients and patients with inadequate response or intolerance to anti‐TNF, respectively); study 3 patients had nonradiographic axial SpA.

Methods

In all 3 studies, patients were randomly assigned (1:1:1) to receive subcutaneous ustekinumab at 45 mg or 90 mg or placebo up to 24 weeks, after which placebo‐treated patients were rerandomized to receive ustekinumab at 45 mg or 90 mg. The primary end point in studies 1 and 2 was the proportion of patients who met the Assessment of SpondyloArthritis international Society criteria for 40% improvement in disease activity (achieved an ASAS40 response). The primary end point in study 3 was the proportion of patients who achieved an ASAS20 response. Other disease activity and safety measures were also evaluated. A week 24 analysis of study 1 was preplanned to determine continuation of studies 2 and 3.

Results

For study 1, the primary and major secondary end points were not met, and the study was discontinued. As a result, studies 2 and 3 were prematurely discontinued before they were fully enrolled. For all 3 studies, neither ustekinumab dose group demonstrated clinically meaningful improvement over placebo on key efficacy end points. The proportion of patients experiencing adverse events in the ustekinumab groups was consistent with that in previous studies.

Conclusion

In these 3 placebo‐controlled trials, efficacy of ustekinumab in the treatment of axial SpA was not demonstrated. The safety profile was consistent with that of studies in other indications.
Multistate modeling and simulation of patient trajectories after allogeneic hematopoietic stem cell transplantation to inform drug development
Authors: James David A. , Ng Jennifer , Wei Jiawei , Vandemeulebroecke Marc
Published: September 2018

We present a case study for developing clinical trial scenarios in a complex progressive disease with multiple events of interest. The idea is to first capture the course of the disease in a multistate Markov model, and then to simulate clinical trials from this model, including a variety of hypothesized drug effects. This case study focuses on the prevention of graft‐versus‐host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (HSCT). The patient trajectory after HSCT is characterized by a complex interplay of various events of interest, and there is no established best method of measuring and/or analyzing treatment benefits. We characterized patient trajectories by means of multistate models that we fitted to a subset of the Center for International Blood and Marrow Transplant Research (CIBMTR) database. Events of interest included acute GvHD of grade III or IV, severe chronic GvHD, relapse of the underlying disease, and death. The transition probability matrix was estimated using the Aalen‐Johansen estimator, and patient characteristics were identified that were associated with different transition rates. In a second step, clinical trial scenarios were simulated from the model assuming various drug effects on the background transition rates, and the operating characteristics of different endpoints and analysis strategies were compared in these scenarios. This helped devise a drug development strategy in GvHD prevention after allogeneic HSCT. More generally, multistate models provide a rich framework for exploring complex progressive diseases, and the availability of a corresponding simulation machinery provides great flexibility for clinical trial planning.
Are green consumers really green? Exploring the factors behind the actual consumption of organic food products
Authors: Testa Francesco , Sarti Silvia , Frey Marco
Published: September 2018

The increasing interest in sustainable consumption has lead several scholars to investigate the determinants that drive the consumption of organic food. Most of this research is based on consumers' self‐reports of their purchasing behavior by exploring declared behavioral intentions. There is a lack of understanding concerning the determinants of organic food consumption based on actual purchasing behavior. To fill this gap, this study is based on a combination of actual purchasing data and self‐reported data from a sample of 79 Italian consumers. The determinants of organic food consumption are explored by analyzing the effects of subjective norms, attitude, perceived behavioral control, intention to buy, organic knowledge, and health consciousness on actual purchasing behavior. Our results suggest that actual purchasing behavior is positively influenced by intention to buy and negatively by subjective norms. Although attitude towards buying organics is positively affected by health consciousness and perceived behavioral control, consumer knowledge about organics is found to influence purchase intentions. Theoretical and managerial implications, along with avenues for future research, are discussed.
Strategies Towards Capturing Nitrogenase Substrates and Intermediates via Controlled Alteration of Electron Fluxes
Authors: Hiller Caleb J. , Lee Chi Chung , Stiebritz Martin T. , Rettberg Lee A. , Hu Yilin
Published: September 2018

Nitrogenase utilizes an ATP‐dependent reductase to deliver electrons to its catalytic component to enable two important reactions: the reduction of N2 to NH4+, and the reduction of CO to hydrocarbons. The two nitrogenase‐based reactions parallel the industrial Haber–Bosch and Fischer–Tropsch processes, yet they occur under ambient conditions. As such, understanding the enzymatic mechanism of nitrogenase is crucial for the future development of biomimetic strategies for energy‐efficient production of valuable chemical commodities. Mechanistic investigations of nitrogenase has long been hampered by the difficulty to trap substrates and intermediates relevant to the nitrogenase reactions. Recently, we have successfully captured CO on the Azotobacter vinelandii V‐nitrogenase via two approaches that alter the electron fluxes in a controlled manner: one approach utilizes an artificial electron donor to trap CO on the catalytic component of V‐nitrogenase in the resting state; whereas the other employs a mismatched reductase component to reduce the electron flux through the system and consequently accumulate CO on the catalytic component of V‐nitrogenase. Here we summarize the major outcome of these recent studies, which not only clarified the catalytic relevance of the one‐CO (lo‐CO) and multi‐CO (hi‐CO) bound states of nitrogenase, but also pointed to a potential competition between N2 and CO for binding to the same pair of reactive Fe sites across the sulfur belt of the cofactor. Together, these results highlight the utility of these strategies in poising the cofactor at a well‐defined state for substrate‐ or intermediate‐trapping via controlled alteration of electron fluxes, which could prove beneficial for further elucidation of the mechanistic details of nitrogenase‐catalyzed reactions.
Reactivity of Selenocystine and Tellurocystine: Structure and Antioxidant Activity of the Derivatives
Authors: Satheeshkumar Kandhan , Raju Saravanan , Singh Harkesh B. , Butcher Ray J.
Published: September 2018

l‐Selenocystine (5) and l‐tellurocystine (6) have been prepared and the reactivity of these amino acids, i.e., oxidation of 5 and 6, has been performed at various pH values. Hydrogen peroxide was used as an oxidant and it was treated with 5 and 6 in excess in acidic and basic media. Compound 5, upon oxidation, afforded SeIV and SeVI products. Selenocysteic acid [HO3SeCH2CH(NH2)COOH] 9, a novel SeVI compound, was isolated and characterised by single‐crystal X‐ray diffraction studies. In contrast, l‐tellurocystine, upon oxidation with H2O2, afforded TeII and TeIV products. Zwitterionic organotellurolate(IV), [TeCl3CH2CH(NH3)COOH] 13, was isolated and characterised by NMR and IR spectroscopy, mass spectrometry and elemental analysis. Compound 13 crystallizes in an orthorhombic space group. l‐Tellurocystine, when reduced with NaBH4, produced the desired tellurolate intermediate, which was trapped with bromoacetic acid. Furthermore, l‐ and d‐tellurocysteine derivatives, [(RTeCH2CH(NH2)COOH) R=phenyl, substituted phenyl and naphthyl (24–39)] were synthesised and evaluated for their glutathione peroxidase (GPx)‐like activities. The results show that l‐tellurocysteine derivatives have higher activity than their D‐tellurocysteine analogues. DFT calculations for l‐tellurocysteine derivatives provided information about the bond lengths and bond angles. This study reveals that the introduction of naphthyl substituents (35–38) leads to twisted conformation of the amino acid derivatives.
Sex‐related differences in left ventricular diastolic function and arterial elastance during admission in patients with heart failure with preserved ejection fraction: The PURSUIT HFpEF study
Authors: Hoshida Shiro , Watanabe Tetsuya , Shinoda Yukinori , Ikeoka Kuniyasu , Minamisaka Tomoko , Fukuoka Hidetada , Inui Hirooki , Ueno Keisuke , Suna Shinichiro , Nakatani Daisaku , Hikoso Shungo , Yamada Takahisa , Yasumura Yoshio , Fuji Hisakazu , Sakata Yasushi ,   on behalf of PURSUIT HFpEF Investigators
Published: September 2018

Background

We previously reported that an index of afterload‐related left ventricular diastolic function, operant diastolic elastance (Ed)/effective arterial elastance (Ea) = E/e’/(0.9 × systolic blood pressure), was significantly higher in elderly hypertensive women. We aimed to determine sex‐related differences in the E/e’‐related indices for left ventricular diastolic function and their related factors during admission in patients with heart failure with preserved ejection fraction (HFpEF).

Hypothesis

Elderly HFpEF women exhibit severe left ventricular diastolic dysfunction associated with different left atrioventricular volume ratio.

Methods

We divided 267 patients with HFpEF (men/women, 116/151) into two groups by age (≥75 years, n = 212; <75 years, n = 55). We examined the alterations of E/e’, E/e’/stroke volume index = Ed, and Ed/Ea, and cardiac structure during admission.

Results

Ed and Ea were significantly higher in women than in men, at admission, especially in patients ≥75 years. Before discharge, not only Ed and Ea but also Ed/Ea was significantly higher in women than in men, especially in patients ≥75 years. Elderly female patients had larger left atrial than left ventricular volume.

Conclusions

Higher afterload‐related left ventricular diastolic elastance, Ed/Ea, in association with higher arterial elastance, Ea, accompanied by left atrioventricular volume mismatch was observed in elderly HFpEF women.
Experimental investigation of effect of tooth geometrical parameters to flow characteristics in slant labyrinth seals
Authors: Zhang Bo , Dou Yuanyuan , Hong Quan , Ji Honghu
Published: September 2018

An experiment investigation was made to study the influence of the geometry parameters of slant straight‐through labyrinth seals on sealing characteristics. 22 models with different geometry parameters were designed, and the geometry parameters studied include seal clearance, fin height, fin pitch, fin tip thickness, and fin number. The results showed that, when p0/pn ranged from 1.2 to 1.8, the discharge coefficient increased with the drop pressure ratio, seal clearance, and fin tip thickness and decreased with fin height, fin pitch, and fin number. The rank of sensitivity of each parameter's variation in the unit size on sealing characteristics is seal clearance, fin tip thickness, fin pitch, back angle, fin height, and front angle. The correlation of different parameters were summarized for the designing of advanced labyrinth seals.
Foraging investment in a long‐lived herbivore and vulnerability to coursing and stalking predators
Authors: Christianson David , Becker Matthew S. , Brennan Angela , Creel Scott , Dröge Egil , M'soka Jassiel , Mukula Teddy , Schuette Paul , Smit Daan , Watson Fred
Published: September 2018

Allocating resources to growth and reproduction requires grazers to invest time in foraging, but foraging promotes dental senescence and constrains expression of proactive antipredator behaviors such as vigilance. We explored the relationship between carnivore prey selection and prey foraging effort using incisors collected from the kills of coursing and stalking carnivores. We predicted that prey investing less effort in foraging would be killed more frequently by coursers, predators that often exploit physical deficiencies. However, such prey could expect delayed dental senescence. We predicted that individuals investing more effort in foraging would be killed more frequently by stalkers, predators that often exploit behavioral vulnerabilities. Further these prey could expect earlier dental senescence. We tested these predictions by comparing variation in age‐corrected tooth wear, a proxy of cumulative foraging effort, in adult (3.4–11.9 years) wildebeest killed by coursing and stalking carnivores. Predator type was a strong predictor of age‐corrected tooth wear within each gender. We found greater foraging effort and earlier expected dental senescence, equivalent to 2.6 additional years of foraging, in female wildebeest killed by stalkers than in females killed by coursers. However, male wildebeest showed the opposite pattern with the equivalent of 2.4 years of additional tooth wear in males killed by coursers as compared to those killed by stalkers. Sex‐specific variation in the effects of foraging effort on vulnerability was unexpected and suggests that behavioral and physical aspects of vulnerability may not be subject to the same selective pressures across genders in multipredator landscapes.
Metallophilic Mercuraazamacrocycles Derived from Bis{6‐formyl‐(2,3,4‐trimethoxy)phenyl}mercury: Reactivity with d10and d8Metal Ions
Authors: Das Shikha , Sharma Sagar , Singh Harkesh B. , Butcher Ray J.
Published: September 2018

A (2+2) Dipodal condensation of bis{6‐formyl‐(2,3,4‐trimethoxy)phenyl}mercury (14) with various 1,2‐disubstitued diamines e.g., ethylenediamine,trans‐1,2‐diaminocyclohexane ando‐phenylenediamine led to the formation of 22‐membered mercuraazametallamacrocycles, [Hg‐{1‐C6H‐2,3,4‐(OCH3)3‐6‐(CHN)}2‐CH2–CH2]2(15), [Hg‐{1‐C6H‐2,3,4‐(OCH3)3‐6‐(CHN)}2‐C6H10]2(16) and [Hg‐{1‐C6H‐2,3,4‐(OCH3)3‐6‐(CHN)}2‐C6H4]2(17) respectively. The acceptor abilities and reactivities of the macrocycles are compared with the corresponding 22‐membered mercuraazametallamacrocycles obtained from the condensation of bis(formylphenyl)mercury (12) with the diamines. Also attempts have been made to prepare macrocycles with functionalized aryldiamines. Orange colored CuIcomplexes,24([15·Cu]ClO4) and26([16·Cu]ClO4), were obtained upon the treatment of [Cu(CH3CN)4ClO4] with macrocycles15and16, respectively. Similarly, brown colored AgIcomplexes,25([15·Ag]ClO4), and27([16·Ag]ClO4) were isolated by reacting macrocycles15and16with AgClO4. The reaction of macrocycle15with equimolar Pt(COD)Cl2afforded cyclometalated platinum(II) complex, Pt‐{1‐C6H‐2,3,4‐(OCH3)3‐6‐(CHN‐CH2)}2(28). Bis(2‐amino‐5‐methylphenyl)mercury (23), shows a very strong intermolecular Hg···Hg interaction. Density functional theory calculations and atoms in molecules analysis revealed the presence of metallophilic d10···d10interactions as well as d10···d8interactions in the synthesized compounds.
Towards Noble‐Metal‐Free Dyads: Ground and Excited State Tuning by a Cobalt Dimethylglyoxime Motif Connected to an Iron N‐Heterocyclic Carbene Photosensitizer
Authors: Zimmer Peter , Burkhardt Lukas , Schepper Rahel , Zheng Kaibo , Gosztola David , Neuba Adam , Flörke Ulrich , Wölper Christoph , Schoch Roland , Gawelda Wojciech , Canton Sophie E. , Bauer Matthias
Published: September 2018

Heteroleptic iron based complexes bearing the 2,6‐bis[3‐(2,6‐diisopropylphenyl)imidazol‐2‐ylidene]pyridine motif and a polypridine ligand have been synthesized and characterized in their ground and excited state. This series of complexes includes a first example of a hetero‐bimetallic complex connecting an iron N‐heterocyclic carbene photosensitizer with a cobalt dimethylglyoxime fragment. Focus is set on the influence of the linker and cobalt center as second ligand at the iron center on the photophysics. While electronic absorption spectroscopy and cyclic voltammetry reveal a weak mutual influence of the single ligands in the heteroleptic complexes, an increasing MLCT lifetime with larger π‐accepting abilities was found by time‐resolved transient absorption spectroscopy, with maximum lifetime in the case of the hetero‐bimetallic dyad. Concurrently the MC lifetimes were observed to decrease. The reported results will allow to develop guidelines for designing bimetallic devices, which may allow electron transfer from the photosensitizer fragment to a catalytically active center.
Detrital zircon record of Mesozoic volcanic arcs in the Lower Cretaceous Mural Limestone, northwestern Mexico
Authors: Madhavaraju Jayagopal , Saucedo‐Samaniego Julio Cesar , Löser Hannes , Espinoza‐Maldonado Inocente Guadalupe , Solari Luigi , Monreal Rogelio , Grijalva‐Noriega Francisco Javier , Jaques‐Ayala Cesar
Published: September 2018

The northwestern part of Mexico, southern Arizona, and southern California witnessed extensive arc magmatism during Late Triassic to Early Cretaceous. Here, we present results from petrography, whole‐rock geochemistry (major and trace including rare‐earth elements), and detrital zircon geochronological studies that were carried out on sandstones and shales of the Mural Limestone exposed in the Rancho Bufalo area. Based on the petrography, sandstones are classified as sublitharenite, litharenite, feldspathic litharenite, and lithic arkose. The sandstones contain higher proportion of monocrystalline quartz than polycrystalline quartz. Sandstones and shales from the various members of the Mural Limestone show large variations in major and trace elements concentrations. The average concentrations of ΣREE (total ΣREE) are lower in sandstones than in shales. The chondrite‐normalized REE patterns of the sandstones and shales are moderately fractionated with light REE (LREE) enrichment relative to heavy REE (HREE) and with flat to slightly depleted HREE patterns. The chemical index of alteration values and A–CN–K relationships of sandstones indicate low to moderate intensity of weathering in the source region; however, shale samples suggesting the source rocks were subjected to moderate intensity of chemical weathering. The chondrite‐normalized REE patterns, Al2O3/TiO2ratio, elemental ratios like Cr/V, Y/Ni, and Eu‐anomaly (Eu/Eu*), and bivariate plots suggest that the sandstones and shales were derived mainly from felsic source rocks. Detrital zircon U–Pb geochronology of sandstones from Fronteras, Rancho Bufalo, and Cerro La Ceja members of the Mural Limestone show five main groups of detrital zircon age populations: (a) Proterozoic, (b) Palaeozoic, (c) Triassic, (d) Jurassic, and (e) Early Cretaceous. Our study suggests that continental volcanic arcs in northwestern Mexico, southern Arizona, and southern California served as the provenance for the Late Triassic‐Jurassic detritus, whereas the Early Cretaceous zircon grains were derived mainly from the active Alisitos volcanic arc along the northwestern coast of Mexico.
FIGO postpartum intrauterine device initiative: Complication rates across six countries
Authors: Makins Anita , Taghinejadi Neda , Sethi Maya , Machiyama Kazuyo , Munganyizi Projestine , Odongo Elly , Divakar Hema , Fatima Parveen , Thapa Kusum , Perera Gamini , Arulkumaran Sabaratnam
Published: September 2018

Objective

To record and analyze complication rates following postpartum intrauterine device (PPIUD) insertion in 48 hospitals in six countries: Sri Lanka, India, Nepal, Bangladesh, Tanzania, and Kenya.

Methods

Healthcare providers were trained in counselling and insertion of PPIUD via a training‐the‐trainer model. Data were collected on methodology, timing, cadre of staff providing care, and number of insertions. Data on complications were collected at 6‐week follow‐up. Statistical analysis was performed to elucidate factors associated with increased expulsion and absence of threads.

Results

From May 2014 to September 2017, 36 766 PPIUDs were inserted: 53% vaginal and 47% at cesarean delivery; 74% were inserted by doctors. Follow‐up was attended by 52%. Expulsion and removal rates were 2.5% and 3.6%, respectively. Threads were not visible in 29%. Expulsion was less likely after cesarean insertion (aOR 0.33; 95% CI, 0.26–0.41), following vaginal insertion at between 10 minutes and 48 hours (aOR 0.59; 95% CI, 0.42–0.83), and when insertion was performed by a nurse (aOR 0.33; 95% CI, 0.22–0.50).

Conclusion

PPIUD has low complication rates and can be safely inserted by a variety of trained health staff. Given the immediate benefit of the one‐stop approach, governments should urgently consider adopting this model.
Successful implementation of immediate postpartum intrauterine contraception services in Edinburgh and framework for wider dissemination
Authors: Cooper Michelle , Cameron Sharon
Published: September 2018

Provision of immediate postpartum intrauterine device (PPIUD) insertion within maternity settings can overcome many of the barriers faced by women in accessing this method after childbirth. Uptake of PPIUD can help reduce the risk of a subsequent unintended pregnancy and improve spacing between births. PPIUD insertion is not yet routinely available in the UK and evidence to support the practical implementation of the service in this setting is lacking. Shared learning and experience of providers may assist in the wider availability of PPIUD. A routine PPIUD service has been successfully established within a public maternity setting in Edinburgh (UK) and this article utilizes an implementation framework to discuss the approach.
The reHISS Three‐Range Exchange Functional with an Optimal Variation of Hartree–Fock and Its Use in the reHISSB‐D Density Functional Theory Method
Authors: Chan Bun , Kawashima Yukio , Hirao Kimihiko
Published: September 2018

In the present study, we have reparametrized the HISS exchange functional. The new “reHISS” exchange provides a balance between short‐ and mid‐range Hartree–Fock exchange (HFX) and a large total HFX coverage, with a fast convergence to zero HFX in the long range. The five parameters in this functional (according to equations 3 and 4 in the main text) are cSR = 0.15, cMR = 2.5279, cLR = 0, ωSR = 0.27, and ωLR = 0.2192. The combination of reHISS exchange with a reparametrized B97c‐type correlation functional (Chan et al., J. Comput. Chem. 2017, 38, 2307) and a D2 dispersion term (s6 = 0.6) gives the reHISSB‐D method. We find it to be more accurate than related screened‐exchange methods and, importantly, its accuracy is more uniform across different properties. Fundamentally, our analysis suggests that the good performance of the reHISS exchange is related to it capturing a near‐optimal proportion of HFX in the range of interelectronic distance that is important for many chemical properties, and we propose this range to be approximately 1–4Å. © 2018 Wiley Periodicals, Inc.
Facile synthesis of multi‐functional 1,3,4‐thiadiazine derivatives bearing phthalazine, pyridazine, and pyrido‐pyridazine moieties
Authors: Gudala Satish , Ambati Srinivasa Rao , Sharma Archi , Patel Jeevan Lal , Vedula Rajeswar Rao , Penta Santhosh
Published: September 2018

A series of novel, multifunctional 1,3,4‐thiadiazine derivatives bearing phthalazines, pyridazines and pyrido‐pyridazines (9–13) have been synthesized via the multicomponent reaction of (3‐(2‐bromo‐2‐[2‐chloropyrimidin‐4‐yl]acetyl)‐2‐chlorophenyl)‐2,6‐dichloro benzene‐sulfonamide with thiocarbohydrazide and various anhydrides. The reactions were performed by refluxing the components in mixed ethanol/acetic acid to afford the corresponding products in good to excellent yields. All the synthesized compounds were characterized by analytical and spectral studies. The developed method features short reaction time, simple work‐up without chromatographic separation, and a broad range of substrate applicability.
The Canadian Dementia Imaging Protocol: Harmonizing National Cohorts
Authors: Duchesne Simon , Chouinard Isabelle , Potvin Olivier , Fonov Vladimir S. , Khademi April , Bartha Robert , Bellec Pierre , Collins D. Louis , Descoteaux Maxime , Hoge Rick , McCreary Cheryl R. , Ramirez Joel , Scott Christopher J.M. , Smith Eric E. , Strother Stephen C. , Black Sandra E. ,   for the CIMA‐Q group and the CCNA group
Published: September 2018

Background

Harmonized protocols to collect imaging data must be devised, employed, and maintained in multicentric studies to reduce interscanner variability in subsequent analyses.

Purpose

To present a standardized protocol for multicentric research on dementia linked to neurodegeneration in aging, harmonized on all three major vendor platforms. The protocol includes a common procedure for qualification, quality control, and quality assurance and feasibility in large‐scale studies.

Study Type

Prospective.

Subjects

The study involved a geometric phantom, a single individual volunteer, and 143 cognitively healthy, mild cognitively impaired, and Alzheimer's disease participants in a large‐scale, multicentric study.

Field Strength/Sequences

MRI was perform with 3T scanners (GE, Philips, Siemens) and included 3D T1w, PD/T2w,
, T2w‐FLAIR, diffusion, and BOLD resting state acquisitions.

Assessment

Measures included signal‐ and contrast‐to‐noise ratios (SNR and CNR, respectively), total brain volumes, and total scan time.

Statistical Tests

SNR, CNR, and scan time were compared between scanner vendors using analysis of variance (ANOVA) and Tukey tests, while brain volumes were tested using linear mixed models.

Results

Geometric phantom T1w SNR was significantly (P < 0.001) higher in Philips (mean: 71.4) than Siemens (29.5), while no significant difference was observed between vendors for T2w (32.0 and 37.2, respectively, P = 0.243). Single individual volunteer T1w CNR was higher in subcortical regions for Siemens (P < 0.001), while Philips had higher cortical CNR (P =  0.044). No significant difference in brain volumes was observed between vendors (P = 0.310/0.582/0.055). The average scan time was 41.0 minutes (SD: 2.8) and was not significantly different between sites (P = 0.071) and cognitive groups (P = 0.853).

Data Conclusion

The harmonized Canadian Dementia Imaging Protocol suits the needs of studies that need to ensure quality MRI data acquisition for the measurement of brain changes across adulthood, due to aging, neurodegeneration, and other etiologies. A detailed description, exam cards, and operators' manual are freely available at the following site: www.cdip-pcid.ca.

Level of Evidence: 2

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;49:456–465.
Phosphorus fertilization reduces the severity of charcoal rot (Macrophomina phaseolina) and the arbuscular mycorrhizal protection in soybean
Authors: Spagnoletti Federico N. , Leiva Micaela , Chiocchio Viviana , Lavado Raul S.
Published: September 2018

The effects of phosphorus (P) application on the relationship between the arbuscular mycorrhizal fungus (AMF) Rhizophagus intraradices and the pathogen Macrophomina phaseolina (charcoal rot) affecting soybean (Glycine max L.) are unknown. We evaluated the effects of P on both the severity of the pathogen and the AMF protection against the charcoal rot in soybean. We conducted greenhouse experiments with a randomized multifactorial design with ten replications. The treatments were: two concentrations of P as superphosphate (0 and 50 kg of P ha−1), inoculated and non‐inoculated with the AMF R. intraradices, and infected and non‐infected with M. phaseolina. Soybean was seeded in pots containing 1 kg of sterilized substrate soil : sand : perlite (7 : 3 : 2). When soybean completed pod formation (R4 phenological stage), the plants were harvested. Plant parameters, mycorrhizal colonization, and disease severity were measured. The presence of M. phaseolina negatively affected soybean biomass, but AMF inoculation improved it. Phosphorus reduced AMF colonization but not arbuscules percentage. Moreover, both P and AMF inoculation had a negative effect on disease severity, although P also reduced mycorrhizal protection. These results suggest that phosphorus application could reduce disease severity, but can simultaneously partially reduce the AMF protection against the pathogen. These effects should be considered in agricultural integrated management practices of soybean.
Organic inclusions evidence, composition, and cathodoluminescence behaviour for the formation conditions of fluorapatite from Anemzi (Morocco)
Authors: Dumańska‐Słowik Magdalena , Wesełucha‐Birczyńska Aleksandra , Heflik Wiesław , Maksymiuk Weronika , Sikorska‐Jaworowska Magdalena
Published: September 2018

Fluorapatite from Anemzi alkaline syenite hosts a wealth of solid organic inclusions, mainly of aliphatic (2,935–2,845 cm−1) and aromatic hydrocarbon compositions (3,100–3,000 cm−1), as well as traces of bituminous matter showing a low degree of ordering. The tiny inclusions built from oxides of titanium (rutile and anatase) are the only mineral phases found in host crystals. The two‐phase, liquid–gas fluid inclusions are composed of aliphatic and aromatic functional groups, revealing bands in the region 1,600–1,200 cm−1. A slightly chemically varied composition and blue, homogenous cathodoluminescence colours, activated mainly by Ce3+, as well as a small volume of mineral inclusions in apatite, indicate that its crystallization, as influenced by hydrocarbon‐ and carbonaceous matter‐bearing fluids, proceeded under stable environmental conditions. It is probable that these fluids were migrated within the adjacent carbonate rocks found in the vicinity of alkaline syenites, which could be the source of organic components entrapped by apatite. A numerous assemblage of organic inclusions is diagnostic feature for gem quality green apatite from Anemzi.
Anticipating Dissolution Issues of Sugar‐Based Surfactants through a Decision Tree Approach
Authors: Gaudin Théophile , Fayet Guillaume , Rotureau Patricia , Pezron Isabelle
Published: September 2018

Sugar‐based surfactants are renewable alternatives to petroleum‐based surfactants in many applications such as detergents and cosmetics. However, their molecular structure often gives rise to relatively stable crystals, which can lead to difficulties in dissolving them in water. This phenomenon is characterized by the Krafft temperature (T
K), above which the surfactant solubility becomes high enough to induce self‐association into micelles. Small changes in the molecular structure can result in large T
K differences, which make rationalization and prediction of T
K challenging. Few models were proposed in the literature, but none of them are applicable to sugar‐based surfactants. In this article, we propose two decision tree models to estimate whether sugar‐based surfactants exhibit potential dissolution issues at room temperature (i.e., T
K above 25 °C or not). The first one, based on the descriptors of the whole molecule including quantum‐chemical ones, was able to correctly classify 86% of the surfactants in the validation set. The second one, built from simple structural counts of the polar headgroup and the alkyl chain, could predict the right class for 78% of the surfactants in the validation set. These classification models account for experimentally known trends between the molecular structure and T
K, such as the impact of the polar headgroup size, the alkyl chain length, and the presence of an amide linkage. To the end, our models were applied to a practical case to show how they can help in designing synthesis procedures of new surfactants.
The chemical profiling of fatty acids during the brewing process
Authors: Olšovská Jana , Vrzal Tomáš , Štěrba Karel , Slabý Martin , Kubizniaková Petra , Čejka Pavel
Published: September 2018

BACKGROUND

Although fatty acids have a beneficial effect on yeast growth during fermentation, their effect on foam and sensory stability of beer is negative. In general, long‐chain fatty acids originate from raw materials, whereas short‐chain acids are produced by yeast during fermentation. If the concentration of short‐chain fatty acids, especially isovaleric and butyric acid, overreaches a sensory threshold, then an unpleasant aroma, such as cheesy or sweaty feet, can be formed in beer.

RESULTS

The distribution of fatty acids, from the preparation of sweet wort to the final beer, was studied using chemometric evaluation. Differences were observed between the decoction and infusion system using four barley varieties. Attention was paid to the behavior of short‐chain fatty acids, namely isovaleric acid. The concentration of isovaleric acid in commercial beers brewed in infusion and decoction systems was approximately 1.4 and 1.0 mg L−1, respectively. The same trend was observed in experimental samples (1.3 and 0.5 mg L−1, respectively). This phenomenon was confirmed experimentally; based on the results, this possibly explains why, during the fermentation, isovaleric acid is coupled with the redox state of yeast cell, which is given by the wort composition (i.e. by the mashing process).

CONCLUSION

The formation of isovaleric acid is not only caused by microbiology infection or by oxidized hops, but also is influenced by the mashing process. © 2018 Society of Chemical Industry
Evaluating green tea quality based on multisensor data fusion combining hyperspectral imaging and olfactory visualization systems
Authors: Li Luqing , Xie Shimeng , Ning Jingming , Chen Quansheng , Zhang Zhengzhu
Published: September 2018

BACKGROUND

The instrumental evaluation of tea quality using digital sensors instead of human panel tests has attracted much attention globally. However, individual sensors do not meet the requirements of discriminant accuracy as a result of incomprehensive sensor information. Considering the major factors in the sensory evaluation of tea, the study integrated multisensor information, including spectral, image and olfaction feature information.

RESULTS

To investigate spectral and image information obtained from hyperspectral spectrometers of different bands, principal components analysis was used for dimension reduction and different types of supervised learning algorithms (linear discriminant analysis, K‐nearest neighbour and support vector machine) were selected for comparison. Spectral feature information in the near infrared region and image feature information in the visible‐near infrared/near infrared region achieved greater accuracy for classification. The results indicated that a support vector machine outperformed other methods with respect to multisensor data fusion, which improved the accuracy of evaluating green tea quality compared to using individual sensor data. The overall accuracy of the calibration set increased from 75% using optimal single sensor information to 92% using multisensor information, and the overall accuracy of the prediction set increased from 78% to 92%.

CONCLUSION

Overall, it can be concluded that multisensory data accurately identify six grades of tea. © 2018 Society of Chemical Industry
Environmental risk resulting from historical land degradation in alluvial plains considered for dam planning
Authors: Breg Valjavec Mateja , Janža Mitja , Smrekar Aleš
Published: September 2018

Land degradation of alluvial plains is an environmental risk for groundwater contamination, stemming from the mobilization of contaminants that can occur from waste‐filled gravel pits. This risk can be increased by river damming and consequential rises in groundwater levels. The presence and characteristics of former historical land degradation of alluvial plains should therefore be considered when planning hydroelectric projects. The aim of this study was to assess the hydrological and environmental impacts of the planned damming of the Sava River on the groundwater, which is the drinking water source for the Slovenian capital Ljubljana. It introduces an integrative approach for determining the characteristics of old waste‐filled gravel pits with stereo image processing of historical aerial photographs and electrical resistivity tomography (ERT) in combination with hydrological modelling. Thirty gravel pits in the study area (17 km2) were identified by stereo image analysis, and three were selected to test results in the field using non‐invasive ERT. Integrating this information with the results of hydrological modelling, we assessed the risk of groundwater contamination from the scenario of the planned damming of the River Sava. The results indicate that the thickness of the unsaturated zone below the identified gravel pits will be reduced by an average of 4 m at median groundwater level conditions during damming, which will increase the vulnerability of groundwater to contamination.
Using a health system learning community strategy to address cancer disparities
Authors: Myers Ronald E. , DiCarlo Melissa , Romney Martha , Fleisher Linda , Sifri Randa , Soleiman Joy , Lambert Emily , Rosenthal Michael
Published: September 2018

Accountable care organizations and health systems have the potential to increase patient engagement in medical care, improve population health outcomes, and reduce costs. Characteristics of highly integrated learning health care systems that seek to achieve these goals have been described in the literature. However, there have been few reports on how health systems, especially those that are loosely integrated, can develop the infrastructure needed to support achievement of these goals. In this report, we describe a learning community strategy that involved forming a coordinating team, a steering committee, and patient and stakeholder advisory committees to address cancer screening and disparities in 2 health systems in southeastern Pennsylvania—Jefferson Health and the Lehigh Valley Health Network. This project engaged diverse patients, health care providers, health system leaders, public and private payers, and other stakeholders in identifying and adapting evidence‐based methods to increase colorectal and lung cancer screening in primary care. Here, we describe components of a health system learning community. In addition, we describe activities in which different components of the learning community were engaged. Finally, we explore prospects for using this type of approach to catalyze the development of learning health care systems.
Anomalous diffusion phenomena with conservation law for the fractional kinetic process
Authors: Tokmagambetov Niyaz , Torebek Berikbol
Published: September 2018

In this remark, an anomalous diffusion phenomena for a fractional kinetic equation is studied. Here, we find well‐posedness conditions for the anomalous diffusion equation for the fractional kinetic process in homogeneous and non‐homogeneous cases, given a discussion about an application to biology. Finally, we derive some numerical experiments.