bluuebunny/crossref_metadata_2025 huggingface dataset:
Fettsäuren und Fettsäurederivate als nachwachsende Plattformmoleküle für die chemische Industrie
Authors: Biermann Ursula , Bornscheuer Uwe T. , Feussner Ivo , Meier Michael A. R. , Metzger Jürgen O.
Published: February 2021

Pflanzliche und tierische Öle und Fette bleiben ein wichtiger nachwachsender Rohstoff der chemischen Industrie. Ihre industrielle Nutzung hat sich in den letzten 10 Jahren von 31 auf 51 Millionen Tonnen pro Jahr erhöht. Dieser Aufsatz fasst die bedeutenden Fortschritte zusammen, die in dieser Zeit in der Oleochemie erzielt wurden, beispielsweise die Reduktion von Fettsäureestern zu Ethern, die selektive Oxidation und oxidative Spaltung von C‐C‐Doppelbindungen, die Synthese von alkylverzweigten Fettstoffen, die isomerisierende Hydroformylierung und Alkoxycarbonylierung sowie die Olefinmetathese. Auch die Nutzung von fettsäurebasierten Chemikalien in der Synthese einer Vielzahl polymerer Materialien hat stark zugenommen. Zusätzlich zu Lipasen und Phospholipasen haben mittlerweile viele weitere Enzyme in der biokatalytischen Fettchemie Anwendung gefunden. Wichtige Entwicklungen haben außerdem neue Eigenschaften bei den Ölen bestehender Nutzpflanzen hervorgebracht, was alternativ auch durch die Verwendung von metabolisch optimierten Mikroorganismen möglich ist.
Multinuclear Ag Clusters Sandwiched by Pt Complex Units: Fluxional Behavior and Chiral‐at‐Cluster Photoluminescence
Authors: Horiuchi Shinnosuke , Moon Sangjoon , Ito Akitaka , Tessarolo Jacopo , Sakuda Eri , Arikawa Yasuhiro , Clever Guido H. , Umakoshi Keisuke
Published: February 2021

Multinuclear Ag clusters sandwiched by Pt complex units were synthesized and characterized by single crystal X‐ray diffraction and NMR studies. The sandwich‐shaped multinuclear Ag complexes showed two different types of fluxional behavior in solution: rapid slippage of Pt complex units on the Ag3 core and a reversible demetalation–metalation reaction by the treatment with Cl anion and Ag ion, respectively. The Ag2 complex obtained by demetalation reaction from the Ag3 complex displayed U to Z isomerization. These multinuclear Ag complexes showed strong photoluminescence whose properties depended on the existence of Pt→Ag dative bonds. The Ag3 complex, identified to be “chiral‐at‐cluster”, was optically resolved by the formation of a diastereomeric salt with a chiral anion. The enantiomers show circular dichroism (CD) and circularly polarized luminescence (CPL) properties which is unprecedented for compounds based on a chiral sandwich structure. Theoretical calculations allow to understand their structural features and photophysical properties.
Evidence of the Lewis‐Amphoteric Character of Tris(pentafluoroethyl)silanide, [Si(C2F5)3]−
Authors: Tiessen Natalia , Keßler Mira , Neumann Beate , Stammler Hans‐Georg , Hoge Berthold
Published: February 2021

According to a first view on the geometrical and electronic structure of the tris(pentafluoroethyl)silanide, this anion appears as a Lewis base. Quantum chemical calculations on perfluoroalkylated silanides show significantly lower HOMO and LUMO energy levels in comparison to their non‐fluorinated counterparts, which implies reduced Lewis basicity and increased Lewis acidity of the [Si(C2F5)3]− ion. With these findings and a HOMO–LUMO gap of 4.80 eV similar to N‐heterocyclic silylenes (NHSis), perfluoroalkyl silanides are predestined to exhibit Lewis‐amphoteric character similar to silylenes. Deprotonation of Si(C2F5)3H with sterically demanding phosphazene bases afforded thermally stable phosphazenium salts of the [Si(C2F5)3]− anion, which add to benzaldehyde, benzophenone, CS2, and CO2 in various manners. This behavior also mirrors the reactivity of silylenes towards ketones as well as heterocumulenes and is rationalized by Lewis amphotericity being inherent in these silanides.
Correlating the Speed of Sound with the Gibbs Energy and Estimating the Speed of Sound in Fatty Acid Methyl Ester and Biodiesel
Authors: Cheewaphan Apinya , Chuensumran Ubol , Phankosol Suriya , Aryusuk Kornkanok , Lilitchan Supathra , Krisnangkura Kanit
Published: February 2021

The relationship between the speed of sound (u) in biodiesel and the change in Gibbs energy (ΔG) has not been described in the literature. With the Gibbs energy additivity method, the relationship between u and ΔG can be expressed as ln(u2) = ΔG/RT + A, where R is the universal gas constant, T is the absolute temperature, and A is a constant. The molecule of fatty acid methyl ester (FAME) was arbitrarily sub‐divided into groups of atoms and a ΔG was assigned to each group of atoms. A new model correlating the speed of sound to the structure of fatty acid was derived. The proposed model was good for estimation of the speed of sound in both FAME and biodiesel at various temperatures with good accuracy. The absolute average deviations for the speed of sound in FAME (65 data points) and in biodiesel (175 data points) were 0.23% and 0.36%, respectively. Only the number of double bonds and carbon atoms of the fatty acid are required for the calculation.
Synthesis and physicochemical investigation of imide‐functionalized silica nanocomposites
Authors: Ali Nisar , Ali Farman , Saeed Shaukat , Said Amir , Sheikh Zeshan Ali , Salman Syed Muhammad , Bilal Muhammad
Published: February 2021

The incorporation of inorganic nanoparticles into polymers have gained significant attention to improving functional properties. The ultimate nanocomposite behaviors are influenced by many parameters, such as microstructural distribution that are produced during the treatment process. Herein, a hybrid material integrating a modified network into a polyimide PI matrix was produced via the sol–gel method by the reaction of pyromellitic dianhydride, 4, 4‐oxydianaline, and 1, 5‐diaminonaphthalene to synthesize copolyimides nanocomposite. The modified polyimide and unmodified polyimide silica (SiO2) nanoparticles were incorporated in the polyimide matrix to have polyimide silica nanocomposite. In modified silica nanoparticles, 3‐aminopropyltriethosilane was introduced to have better compatibility among inorganic–organic hybrid with similar chemical contact due to their flexible alkyl group. The surface morphology or structure of silica and polyimide was affirmed by scanning electron microscopy, Fourier transforms infrared spectroscopy confirmed the synthesis of pure polyimide, unmodified polyimide, and modified polyimide silica via presence and absence of certain peaks. Thermogravimetric analysis (TGA) results showed high thermal stability of nanocomposites as silica content increases. In contrast to unmodified silica, the modified silica provides more thermal stability to the nanocomposites. Dynamic mechanical analysis was used to investigate the tensile stress of pure polyimide, unmodified, and modified silica nanocomposites. Thermal stability, storage modulus, and moisture absorption of these hybrid materials were improved with silica nanoparticles. The TG mass spectrum confirms the successful synthesis of modified silica networks. The substituted silica nanoparticles show higher mechanical toughness and storage in modified compared to unmodified silica nanocomposite, which exhibits stronger binding attraction between silica nanoparticles and polyimide matrix.
Weakening macroalgal feedbacks through shading on degraded coral reefs
Authors: Dajka Jan‐Claas , Beasley Victoria , Gendron Gilberte , Barlow Jos , Graham Nicholas A.J.
Published: February 2021

Extensive and dense macroalgal fields can compromise the ecosystem function of habitat mosaics on reefs owing to their limiting effect on patch connectivity. Macroalgae can maintain and increase their dominance with effective self‐reinforcing feedback mechanisms. For example, macroalgae can form dense beds, supressing coral settlement and grazing by herbivores. This compromised ecosystem function can lead to major socioeconomic and ecological changes.

Dense macroalgal beds were shaded with submerged shade sails of two sizes and changes to the underlying benthos and feeding rates of herbivorous fishes were recorded. The shade sails reduced the algae's ability to photosynthesize by 29%. After 6 weeks, macroalgal cover was reduced by 24% under small sails and by 51% under large sails. Small shade sails reduced turf algal growth by 23%, while large sails reduced growth by 82%.

Three months after removal of the shade sails, algal beds had almost completely regrown. During this regrowth period, herbivore bites taken from the experiment's substrates were recorded, with grazing impact reducing significantly with time.

This study is the first to achieve macroalgal reduction via the alteration of the light regime. While macroalgae regrew in this relatively short‐term experiment, shading may be a viable reef management approach that aims to maximize habitat mosaics on coral reefs, particularly if used in combination with other intervention methods.
Synthesis, in silico, and in vitro studies of novel dopamine D2 and D3 receptor ligands
Authors: Elek Milica , Djokovic Nemanja , Frank Annika , Oljacic Slavica , Zivkovic Aleksandra , Nikolic Katarina , Stark Holger
Published: February 2021

Dopamine is an important neurotransmitter in the human brain and its altered concentrations can lead to various neurological diseases. We studied the binding of novel compounds at the dopamine D2 (D2R) and D3 (D3R) receptor subtypes, which belong to the D2‐like receptor family. The synthesis, in silico, and in vitro characterization of 10 dopamine receptor ligands were performed. Novel ligands were docked into the D2R and D3R crystal structures to examine the precise binding mode. A quantum mechanics/molecular mechanics study was performed to gain insights into the nature of the intermolecular interactions between the newly introduced pentafluorosulfanyl (SF5) moiety and D2R and D3R. A radioligand displacement assay determined that all of the ligands showed moderate‐to‐low nanomolar affinities at D2R and D3R, with a slight preference for D3R, which was confirmed in the in silico studies. N‐{4‐[4‐(2‐Methoxyphenyl)piperazin‐1‐yl]butyl}‐4‐(pentafluoro‐λ6‐sulfanyl)benzamide (7i) showed the highest D3R affinity and selectivity (pKi values of 7.14 [D2R] and 8.42 [D3R]).
Altered patterns of brain dynamics linked with body mass index in youth with autism
Authors: Kupis Lauren , Goodman Zachary T. , Kircher Leigha , Romero Celia , Dirks Bryce , Chang Catie , Nomi Jason S. , Uddin Lucina Q.
Published: February 2021

Children with autism spectrum disorder (ASD) have higher rates of overweight and obesity (OWOB) compared with typically developing (TD) children. Brain functional connectivity differences have been shown in both ASD and OWOB. However, only one study to date has examined ASD and OWOB concurrently, so little is known regarding the neural mechanisms associated with the higher prevalence of OWOB and its behavioral impacts in ASD. We investigated co‐activation patterns (CAPs) of brain regions identified by independent component analysis in 129 children and adolescents between 6 and 18 years of age (n = 68 ASD). We examined the interaction between body mass index (BMI) and diagnosis in predicting dynamic brain metrics (dwell time, DT; frequency of occurrence, and transitions between states) as well as dimensional brain‐behavior relationships. The relationship between BMI and brain dynamics was moderated by diagnosis (ASD, TD), particularly among the frequency of CAP 4, characterized by co‐activation of lateral frontoparietal, temporal, and frontal networks. This pattern was negatively associated with parent‐reported inhibition skills. Children with ASD had shorter CAP 1, characterized by co‐activation of the subcortical, temporal, sensorimotor, and frontal networks, and CAP 4 DTs compared with TD children. CAP 1 DT was negatively associated with cognitive flexibility, inhibition, social functioning, and BMI. Cognitive flexibility moderated the relationship between BMI and brain dynamics in the visual network. Our findings provide novel evidence of neural mechanisms associated with OWOB in children with ASD. Further, poorer cognitive flexibility may result in increased vulnerability for children with ASD and co‐occurring OWOB.

Lay Summary

Obesity is a societal epidemic and is common in autism, however, little is known about the neural mechanisms associated with the higher rates of obesity in autism. Here, we find unique patterns of brain dynamics associated with obesity in autism that were not observed in typically developing children. Further, the relationship between body mass index and brain dynamics depended on cognitive flexibility. These findings suggest that individuals with autism may be more vulnerable to the effects of obesity on brain function. Autism Res 2021, 14: 873–886. © 2021 International Society for Autism Research, Wiley Periodicals LLC.
Exploring the role of India’s secondary school compulsory curriculum textbooks in students’ national identity constructions in an overseas school
Authors: Qazi M. Habib , Taysum Alison
Published: February 2021

This study problematises the contribution of India’s school textbooks in students’ national identity constructions in an overseas school in the Kingdom of Saudi Arabia. The textbooks construct students’ national identity on the concepts of India’s secular democracy, colonial resistance and equal citizenship rights. Notwithstanding study participants’ ambivalent identification with these ideals, they mostly express confusing identities evincing religious tendencies, gendered beliefs towards women and antipathy for India’s neighbouring states. This entails implications for India’s national cohesion and students’ ability to live in harmony with other communities in the diasporic setting. It also poses risks to the United Nations Sustainable Development Goals (SDGs), 2030.
Machine learning applied for metabolic flux‐based control of micro‐aerated fermentations in bioreactors
Authors: Mesquita Thiago J. B. , Campani Gilson , Giordano Roberto C. , Zangirolami Teresa C. , Horta Antonio C. L.
Published: February 2021

Various bio‐based processes depend on controlled micro‐aerobic conditions to achieve a satisfactory product yield. However, the limiting oxygen concentration varies according to the micro‐organism employed, while for industrial applications, there is no cost‐effective way of measuring it at low levels. This study proposes a machine learning procedure within a metabolic flux‐based control strategy (SUPERSYS_MCU) to address this issue. The control strategy used simulations of a genome‐scale metabolic model to generate a surrogate model in the form of an artificial neural network, to be used in a micro‐aerobic fermentation strategy (MF‐ANN). The meta‐model provided setpoints to the controller, allowing adjustment of the inlet air flow to control the oxygen uptake rate. The strategy was evaluated in micro‐aerobic batch cultures employing industrial Saccharomyces cerevisiae yeast, with defined medium and glucose as the carbon source, as a case study. The performance of the proposed control scheme was compared with a conventional fermentation and with three previously reported micro‐aeration strategies, including respiratory quotient‐based control and constant air flow rate. Due to maintenance of the oxidative balance at the anaerobiosis threshold, the MF‐ANN provided volumetric ethanol productivity of 4.16 g·L−1·h−1 and a yield of 0.48 gethanol.gsubstrate−1, which were higher than the values achieved for the other conditions studied (maximum of 3.4 g·L−1·h−1 and 0.35–0.40 gethanol·gsubstrate−1, respectively). Due to its modular character, the MF‐ANN strategy could be adapted to other micro‐aerated bioprocesses.
Exploring business models for sustainability: A bibliographic investigation of the literature and future research directions
Authors: Preghenella Nadia , Battistella Cinzia
Published: February 2021

This study aims to review the state of the art on the topic of business models for sustainability. The paper screens 1744 peer‐reviewed papers with no temporal limitation and undertakes three stages of literature review analysis of a final set of 134 papers with a combination of systematic, bibliometric and multivariate techniques. The first output is the identification of six wide different but interconnected research streams of business model for sustainability: namely, elements and structure; applications; different types of business model for sustainability; transition process; circularity as sustainability; and technical aspects of innovation. A theoretical framework that allows to understand the themes explored by the literature so far and gives an interpretation of the evolution of the literature has been produced. Finally, the analysis provides opportunities and research directions for future research. The paper originality lies in providing the first co‐citation analysis of business models for sustainability with a descriptive and critical study by identifying main research trends and relevant gaps in the literature and by providing future research directions.
Cu(II)‐Binding N‐Terminal Sequences of Human Proteins
Authors: Frączyk Tomasz
Published: February 2021

Proteins anchor copper(II) ions mainly by imidazole from histidine residues located in different positions in the primary protein structures. However, the motifs with histidine in the first three N‐terminal positions (His1, His2, and His3) show unique Cu(II)‐binding properties, such as availability from the surface of the protein, high flexibility, and high Cu(II) exchangeability with other ligands. It makes such sequences beneficial for the fast exchange of Cu(II) between ligands. Furthermore, sequences with His1 and His2, thus, non‐saturating the Cu(II) coordination sphere, are redox‐active and may play a role in Cu(II) reduction to Cu(I). All human protein sequences deposited in UniProt Knowledgebase were browsed for those containing His1, His2, or His3. Proteolytically modified sequences (with the removal of a propeptide or Met residue) were taken for the analysis. Finally, the sequences were sorted out according to the subcellular localization of the proteins to match the respective sequences with the probability of interaction with divalent copper.
Covid‐19 laryngectomized patients care, on field experience, and considerations
Authors: Ricciardiello Filippo , Caraglia Michele , Romano Gian Marco , Longo Giuseppe , Russo Giuseppe , Mazzone Salvatore , Accardo Nunzio , Abate Teresa , Oliva Flavia , Motta Giovanni , Bocchetti Marco
Published: February 2021

Laryngectomized patients showed an unconventional response to SARS‐CoV‐2 viral infection. Here, we describe five different patient cases along with our interpretation of the phenomena and suggestions for their safe management.
Efficient Oxygen Evolution Electrocatalyst by Incorporation of Nickel into Nanoscale Dicobalt Boride
Authors: Schuch Jona , Klemenz Sebastian , Schuldt Patrick , Zieschang Anne‐Marie , Dolique Stephanie , Connor Paula , Kaiser Bernhard , Kramm Ulrike I. , Albert Barbara , Jaegermann Wolfram
Published: February 2021

Recently, transition metal borides attracted increased attention as electrocatalysts for the oxygen evolution reaction. Here, we show how the incorporation of nickel into nanoscale dicobalt boride results in an improvement of the activity and stability of the catalyst in alkaline electrolytes. The borides are obtained by a one‐step solution synthesis, calcined, and characterized by X‐ray diffraction and scanning electron microscopy. For

(Co1‐xNix)2B (x=0, 0.1, 0.2, 0.3, 0.4, and 0.5), (Co0.9Ni0.1)2B shows the best performance with an overpotential of η=371 mV at 10 mA cm−2 in 1 M KOH. Normalization to the electrochemical surface area shows a clear dependence on the activity with rising nickel content. X‐ray photoelectron spectroscopy reveals that the catalyst is modified under reaction conditions and indicates that CoOOH and Ni(OH)2 are formed as active surface species. Flame atomic absorption spectroscopy (F‐AAS) measurements show that no cobalt is dissolved during the electrochemical investigations, but the nickel concentration is increased on the surface of the catalyst as follows from XPS measurements after the electrochemical investigation.
Highly Stable Ultrafine Boron‐Doped NiCo@Carbon Nanoparticles as a Robust Electrocatalyst for the Hydrogen Evolution Reaction
Authors: Adegbemiga Yusuf Bashir , Xie Meng , Yaseen Waleed , Judith Oluigbo Chidinma , Wei Wei , Xu Yuanguo , Xie Jimin
Published: February 2021

Developing robust, stable, low‐cost, and highly active environmentally friendly electrocatalysts for the hydrogen evolution reaction (HER) is necessary for realizing alternative clean energy sources. We prepared highly stable ultrafine NiCo@boron‐doped carbon (NiCo@BC) by using a simple reduction method. As an excellent and highly stable HER electrocatalyst, the as‐prepared NiCo@BC 500 °C nanoparticle catalyst displays a satisfying HER performance, delivering a low geometrical overpotential of 209 mV at 10 mA cm−2 current density, a small Tafel slope of 60 mV dec−1, and an outstanding time‐dependent stability after 200 hours in an alkaline solution, which is one of the best reported B‐doped HER electrocatalysts. The outstanding catalytic activity arises from synergetic relationships between B‐doped carbon and NiCo, coexisting in the as‐prepared hybrid product with the crystalline nature of the hybrid NiCo@BC products bearing plentiful catalytically active sites and good electrical conductivity. The promising combination of robust stability, high catalytic performance, and a simplistic preparation approach provides a new‐type of electrocatalyst for clean energy technologies.
Electrochemical Characterization of Bis‐Cobalt Hexaphyrin: A Selective Electrocatalyst for the Two‐Electron Reduction of Oxygen in Acid Media
Authors: Ye Lina , Fang Yuanyuan , Ou Zhongping , Feng Ru , Chen Minyuan , Guo Rui , Kadish Karl M.
Published: February 2021

A bis‐cobalt(II) hexaphyrin was synthesized and characterized as to its electrochemical and spectroelectrochemical properties in nonaqueous media. The examined compound is represented as HexaPyCo2 where HexaPy represents an expanded macrocycle containing six pyrroles and six meso‐2,6‐difluorophenyl substituents. Three or four reductions can be observed for the bis‐cobalt hexaphyrin depending upon the solvent. The first two reductions are reversible and well separated in PhCN (E1/2=−0.50 and −0.90 V) or CH2Cl2 (E1/2=−0.52 and −0.87 V) containing 0.1 M TBAP. This contrasts with what is observed in pyridine where the first two one‐electron additions are overlapped in potential and occur at an apparent E1/2=−0.73 V vs SCE. The third and fourth reductions of the bis‐cobalt(II) hexaphyrin are irreversible and coupled to chemical reactions in PhCN or CH2Cl2 but well‐defined one‐electron transfers are seen in pyridine where the 250 mV difference between reversible E1/2 values (−1.28 and −1.53 V) matches almost perfectly with a 240 mV separation in potentials between the third and fourth reductions of a related bis‐Cu(II) hexaphyrin under the same solution conditions. The oxygen reduction reaction (ORR) was also investigated using HexaPyCo2 as a catalyst in 1.0 M HClO4. The results of rotating‐disk and rotating‐ring‐disk voltammetry show that the bis‐cobalt hexaphyrin is a selective catalyst for the 2‐electron ORR and gives 95 % H2O2 as the product in acid media.
Transition‐Metal‐Catalyzed Synthesis of Chiral Allylboronates†
Authors: Ming Wenbo , Liu Xiaocui , Mao Lujia , Gu Xiao , Ye Qing
Published: February 2021

Since the pioneering work on Cr(III)‐catalyzed enantioselective [4+2]/allylboration reported by Hall and co‐workers, a variety of catalytic methodologies for the asymmetric allylic borylation reactions have been developed to provide chiral allylboronates bearing a wide range of functional groups. This review article describes recent advances in transition‐metal catalyzed preparation of chiral allylboronates, especially on those in the past three years, and with the emphasis on the aspect of asymmetric catalysis. According to the mechanism of achieving the chemo‐, regio‐, stereo‐ and enantioselectivities, the discussion is divided in two parts: substrate‐controlled and catalyst‐controlled synthesis.
A Computational Study of Asymmetric Hydrogenation of 2‐Phenyl Acrylic Acids Catalyzed by a Rh(I) Catalyst with Ferrocenyl Chiral Bisphosphorus Ligand: The Role of Ion‐Pair Interaction†
Authors: Fan Xiangru , Zheng Lini , Yang Yuhong , Dong Xiu‐Qin , Zhang Xumu , Chung Lung Wa
Published: February 2021

Main observation and conclusion

Asymmetric hydrogenation reaction is one of the most efficient synthetic methods to form useful chiral compounds for synthetic chemistry, medicinal chemistry and material chemistry. Generally, the enantioselectivity of many hydrogenation reactions is controlled by steric hindrance between the chiral ligand and substrate. Recently, Zhang group developed a highly asymmetric hydrogenation of 2‐aryl and 2‐alkyl acrylic acids catalyzed by a Rh(I) catalyst with a chiral Wudaphos ligand. The excellent enantioselectivity of this asymmetric reaction was proposed to be controlled by ion‐pair interaction between the substrate and chiral ligand. In this study, a systematic density functional theory study has been carried out to investigate the reaction mechanism and origin of the enantioselectivity. Our computational results suggest that this reaction follows the classic mechanism involving oxidative addition of H2, migratory insertion and reductive elimination. Different from the C=C coordination to the metal in the common oxidative addition step, our study found that the chelation of the carboxyl group of the substrate to the cationic Rh(I) metal is more favorable in this oxidative addition step. The high enantioselectivity is proposed to be dictated by a better catalyst/substrate geometric complementarity in the major pathway to have less distortion of the catalyst for a strong ion‐pair interaction.
Chiral Phosphoric Acid Catalyzed Asymmetric Synthesis of Axially Chiral Compounds†
Authors: Da Bing‐Chao , Xiang Shao‐Hua , Li Shaoyu , Tan Bin
Published: February 2021

The well‐defined conformational properties of axially chiral compounds bring extraordinary values to an assortment of bioactive molecules, advanced materials, organocatalysts as well as chiral ligands in asymmetric transformations. The demonstrated usefulness and untapped potential of axially chiral structural motifs stimulate increasing efforts to develop novel and efficient approaches for their preparation. In this regard, the chiral phosphoric acids broadly used in asymmetric Brønsted acid catalysis have shown high relevance for atroposelective synthesis as well. Our strong interest in reaction chemistry of atropisomers has established a rewarding research programme in our group. The course of studies will be recounted in this Account, with discussion focused on the use of chiral phosphoric acids to catalyze construction of several key axially chiral structures such as BINAM, BINOL, NOBIN, arylquinones, SPINOL, arylpyrrole analogues and axially chiral alkenes.

What is the most favorite and original chemistry developed in your research group?

Organocatalytic asymmetric arene C—H functionalization.

What is the most important personality for scientific research?

Persistence, smart thinking.

What are your hobbies?

Playing basketball, playing card.

What's your favorite book(s)?

The Ordinary World by the famous Chinese writer Yao Lu.

Who influences you mostly in your life?

My parents and my supervisors Prof. Guofu Zhong and Carlos F. Barbas III.

How do you supervise your students?

I advise my students to work smartly and work hard.
Effectiveness and safety of single transseptal ablation for atrial fibrillation in real‐word practice
Authors: Park Yoon Jung , Yu Hee Tae , Kim Tae‐Hoon , Uhm Jae‐Sun , Joung Boyoung , Lee Moon‐Hyoung , Pak Hui‐Nam
Published: February 2021

Background

We have previously reported that unilateral groin‐single transseptal (ST) ablation in patients with paroxysmal atrial fibrillation (AF) was safe and significantly reduced patient discomfort compared with bilateral groin‐double transseptal (DT) ablation.

Hypothesis

In the present study, we hypothesized that ST ablation would be as effective and safe as DT ablation in real‐world practice like previous study. Among the 1765 consecutive patients in the Yonsei AF ablation cohort from October 2015 to January 2020, 1144 patients who underwent radiofrequency ablation were included for the analysis. Among them, 450 underwent ST ablation and 694 underwent DT ablation.

Results

The total procedure time, ablation time, and fluoroscopy time were longer in the ST group than in the DT group (p < .05 for all). The hospital stay after catheter ablation was 1.3 ± 1.1 days which was longer in DT group than ST group (p = .001). No significant difference was observed in the complication rate (p = .263) and AF‐free survival rate (log‐rank p = .19) between the groups. However, after excluding patients who used antiarrhythmic drugs when AF recurred, the AF‐free survival rates were lower in the DT group than in the ST group before and after propensity score matching (log‐rank p = .026 and .047, respectively).

Conclusion

Although the ST approach increases the procedure time compared with the DT approach owing to the need for more frequent catheter exchanges, the ST approach is a feasible and safe strategy for AF ablation in terms of rhythm outcomes and risk of complications.
Gastroesophageal reflux disease: A risk factor for laryngeal squamous cell carcinoma and esophageal squamous cell carcinoma in the NIH‐AARP Diet and Health Study cohort
Authors: Wang Shao‐Ming , Freedman Neal D. , Katki Hormuzd A. , Matthews Charles , Graubard Barry I. , Kahle Lisa L. , Abnet Christian C.
Published: February 2021

Background

Prior studies have suggested that gastroesophageal reflux disease (GERD) may be associated with risk of squamous cancers of the larynx and esophagus; however, most of these studies have had methodological limitations or insufficient control for potential confounders.

Methods

We prospectively examined the association between GERD and esophageal adenocarcinoma (EADC), esophageal squamous cell carcinoma (ESCC), and laryngeal squamous cell carcinoma (LSCC) in 490,605 participants of the NIH‐AARP Diet and Health Study cohort who were 50‐71 years of age at baseline. Exposure to risk factors were obtained from the baseline questionnaire. GERD diagnosis was extracted among eligible participants via linkage to Medicare diagnoses codes and then multiply imputed for non–Medicare‐eligible participants. Hazard ratios (HRs) and 95% CIs of GERD were computed using Cox regression.

Results

From 1995 to 2011, we accrued 931 cases of EADC, 876 cases of LSCC, and 301 cases of ESCC in this cohort and estimated multivariable‐adjusted HRs of 2.23 (95% CI, 1.72‐2.90), 1.91 (95% CI, 1.24‐2.94), and 1.99 (95% CI, 1.39‐2.84) for EADC, LSCC, and ESCC, respectively. The associations were independent of sex, smoking status, alcohol intake, and follow‐up time periods. We estimated that among the general population in the United States, 22.04% of people aged 50‐71 years suffered from GERD. Using risk factor distributions for the United States from national survey data, 16.92% of LSCC cases and 17.32% of ESCC cases among individuals aged 50‐71 years were estimated to be associated with GERD.

Conclusion

GERD is a common gastrointestinal disorder, but future prospective studies are needed to replicate our findings. If replicated, they may inform clinical surveillance of GERD patients and suggest new avenues for prevention of these malignancies.
Photometric and colorimetric analysis of light emitting diode luminaires for interior lighting design
Authors: Moyano David B. , Moyano Silvia B. , López Miguel G. , Aznal Alejandro S. , González L. Roberto A.
Published: February 2021

Light emitting diode (LED) lighting is increasing in popularity because it has many advantages over incandescent lamps such as energy efficiency, robustness, longevity, and good stability over time. The aim of this study was to check the color parameters, efficiency, and effectiveness of LED lamps used for indoor lighting to ensure that the luminaires sampled complied with the labeling requirements. The tests were carried out according to the standard UNE‐EN 13032‐4:2016 by determining the angular distribution of illuminance of the lamps in a photometric laboratory, minimizing the incidence of detection of reflections and stray light, and using the parameters of 15 LED lights collected by inspectors of the Ministry of Consumer Affairs of Castilla la Mancha. The samples were acquired randomly from various commercial establishments. The analysis of the results allowed us to verify that the LED lights complied with the current regulations.
Multitime Distribution in Discrete Polynuclear Growth
Authors: Johansson Kurt , Rahman Mustazee
Published: February 2021

We study the multitime distribution in a discrete polynuclear growth model or, equivalently, in directed last‐passage percolation with geometric weights. A formula for the joint multitime distribution function is derived in the discrete setting. It takes the form of a multiple contour integral of a block Fredholm determinant. The asymptotic multitime distribution is then computed by taking the appropriate KPZ‐scaling limit of this formula. This distribution is expected to be universal for models in the Kardar‐Parisi‐Zhang universality class. © 2021 The Authors. Communications on Pure and Applied Mathematics published by Wiley Periodicals LLC.
Surfaces of VO2‐Polymorphs: Structure, Stability and the Effect of Doping
Authors: Stahl Berenike , Bredow Thomas
Published: February 2021

Vanadium dioxide is an interesting and frequently applied material due to its metal‐insulator phase transition. However, there are only few studies of the catalytic activity and surface properties of different VO2 polymorphs. Therefore, we investigated the properties of the surfaces of the most stable VO2 phases theoretically at density‐functional theory level using a self‐consistent hybrid functional which has demonstrated its accuracy for the prediction of structural, electronic and energetic properties in a previous study. We found that the surfaces of the rutile R phase of VO2 are not stable and show a spontaneous phase transition to the monoclinic M1 phase. Doping with Mo stabilizes the surfaces with rutile structure even for small dopant concentrations (6.25 %). Both M1 and R surfaces strongly relax, with and without doping. In particular the metal‐metal distances in the uppermost layers change by up to 0.4 Å. Mo segregates in the topmost layer of both R and M1 phases. The electronic structure is only slightly changed upon doping.
Coexpression gene network analysis of cold‐tolerant Solanum commersonii reveals new insights in response to low temperatures
Authors: Esposito Salvatore , Aversano Riccardo , Bradeen James , D'Amelia Vincenzo , Villano Clizia , Carputo Domenico
Published: February 2021

Among abiotic stressors, cold is one of the most harmful for the cultivated potato (Solanum tuberosum L.), a frost‐sensitive crop. RNA sequencing (RNA‐seq) profiling of two different clones of wild potato (S. commersonii Dun.) contrasting in their capacity to withstand low temperatures revealed a higher number of differentially expressed genes (DEGs) under nonacclimated conditions (NAC) in tolerant clone cmm1T vs. the susceptible cmm6‐6 (1,002 and 8,055 DEGs, respectively). By contrast, the number of DEGs was much more comparable when both genotypes were under acclimated conditions (AC). Indeed, a total of 5,650 and 8,936 DEGs were detected in the tolerant genotype vs. the susceptible. Gene ontology (GO) classification under NAC showed a significant role for transcription regulation, lignin catabolic genes, and regulation of plant type secondary cell wall in the cold‐tolerant genotypes, suggesting an important role in conferring tolerance response. By contrast, response to stress and response to stimuli were enriched GO categories in both clones under AC. Unsigned weighted correlation networks analysis (WGCNA) allowed identification of coexpressed hub genes with possible main regulatory functions and major impacts on the phenotype. Among those identified, we clarified the role of CBF4. This gene showed contrasting expression profiles in the two clones under NAC, being induced in cold‐tolerant cmm1T but suppressed in susceptible cmm6‐6. By contrast, under AC, CBF4 was upregulated in both clones. Our study provides a global understanding of mechanisms involved following exposure to NAC and AC in S. commersonii. The mechanisms described here will inform future investigations for detailed validation in studies regarding cold tolerance in plants.
Mode effect: An issue of perspective? Writing mode differences in a spelling assessment in German children with and without developmental dyslexia
Authors: Jung Stefanie , Moeller Korbinian , Klein Elise , Heller Juergen
Published: February 2021

Digital technology has an increasing influence on writing processes. In this context, the question arises whether changes in writing mode (i.e., handwriting vs. computer‐keyboard typing) also require changes in writing assessments. However, data directly comparing writing mode influences in children with and without developmental writing deficits are scarce. This study investigated the influence of writing mode in German‐speaking, typically developing children and children with developmental dyslexia (DD) from two different levels. Results showed on a general level that writing mode influenced overall spelling accuracy, writing time, and self‐corrections comparably in children with and without DD. On a rule‐specific level, outcomes for writing time and self‐corrections substantiated these findings. However, as regards spelling accuracy, a mode effect was only apparent for capitalization, whereas other spelling rules were resistant to writing mode influences. Present findings suggest that a mode effect is present only for typing specific aspects (e.g., capitalization) rather than reflecting a general influence on orthographic principles (e.g., grapheme–phoneme assignment, morphologic principles). These mode‐specific aspects seem to comparably affect the writing performance of typically developing children and children with DD. We recommend writing assessments to consider that different writing modes may influence individual spelling rules differently.
Effect of dapagliflozin on anaemia in DAPA‐HF
Authors: Docherty Kieran F. , Curtain James P. , Anand Inder S. , Bengtsson Olof , Inzucchi Silvio E. , Køber Lars , Kosiborod Mikhail N. , Langkilde Anna Maria , Martinez Felipe A. , Ponikowski Piotr , Sabatine Marc S. , Schou Morten , Sjöstrand Mikaela , Solomon Scott D. , Jhund Pardeep S. , McMurray John J.V. ,   DAPA‐HF Investigators and Committees
Published: February 2021

Aim

Anaemia is common in heart failure and associated with worse outcomes. We examined the effect of dapagliflozin on correction of anaemia in patients with heart failure (HF) and reduced ejection fraction in DAPA‐HF. We also analysed the effect of dapagliflozin on outcomes, according to anaemia status at baseline.

Methods and results

Anaemia was defined at baseline as a haematocrit <39% in men and <36% in women. Resolution of anaemia was defined as two consecutive haematocrit measurements above these thresholds at any time during follow‐up. The primary outcome was a composite of worsening HF (hospitalization or urgent visit requiring intravenous therapy) or cardiovascular death. Of the 4744 patients randomized in DAPA‐HF, 4691 had a haematocrit available at baseline, of which 1032 were anaemic (22.0%). The rate of the primary outcome was higher in patients with anaemia (16.1 per 100 person‐years) compared with those without (12.9 per 100 person‐years). Anaemia was corrected in 62.2% of patients in the dapagliflozin group, compared with 41.1% of patients in the placebo group. The effect of dapagliflozin on the primary outcome was consistent in anaemic compared with non‐anaemic patients [hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.52–0.88 vs. HR 0.76, 95% CI 0.65–0.89; interaction P = 0.44]. Similar findings were observed for cardiovascular death, HF hospitalization, and all‐cause mortality. Patients with resolution of anaemia had better outcomes than those in which anaemia persisted.

Conclusion

Patients with anaemia had worse outcomes in DAPA‐HF. Dapagliflozin corrected anaemia more often than placebo and improved outcomes, irrespective of anaemia status at baseline.
High‐dimensional multivariate geostatistics: A Bayesian matrix‐normal approach
Authors: Zhang Lu , Banerjee Sudipto , Finley Andrew O.
Published: February 2021

Joint modeling of spatially oriented dependent variables is commonplace in the environmental sciences, where scientists seek to estimate the relationships among a set of environmental outcomes accounting for dependence among these outcomes and the spatial dependence for each outcome. Such modeling is now sought for massive data sets with variables measured at a very large number of locations. Bayesian inference, while attractive for accommodating uncertainties through hierarchical structures, can become computationally onerous for modeling massive spatial data sets because of its reliance on iterative estimation algorithms. This article develops a conjugate Bayesian framework for analyzing multivariate spatial data using analytically tractable posterior distributions that obviate iterative algorithms. We discuss differences between modeling the multivariate response itself as a spatial process and that of modeling a latent process in a hierarchical model. We illustrate the computational and inferential benefits of these models using simulation studies and analysis of a vegetation index data set with spatially dependent observations numbering in the millions.
Orthogonal frequency division multiplexing with index modulation by using multiple constellation sets
Authors: Acar Yusuf
Published: February 2021

In this article, a new transmission method named enhanced orthogonal frequency division multiplexing (E‐OFDM) is proposed to increase the spectral efficiency (SE) of the OFDM. The proposed method conveys information bits not only by theM‐ary symbols but also by the multiple different constellation sets. In the proposed method, we build the sub‐blocks by splitting the whole OFDM into pieces. Then, we use different constellation sets in each sub‐block and we assign the extra bits to them to increase the SE of the OFDM systems. Consequently, at the same modulation level, the proposed method has higher SE than the conventional OFDM system. The simulation results also show that the proposed method achieves better bit error rate (BER) performance than the conventional OFDM system with tolerable complexity. For example, the proposed method with a sub‐block size 2 doubles the SE of the conventional OFDM method with BPSK modulation, and also it has approximately 1.6 dB better BER performance than the conventional OFDM at BER =10−4. New constellation designs and receiver algorithm for the detection of additional bits are also presented.
Production and evaluation of the chemical and mechanical properties of nanocellulose and nanowood starch‐based biodegradable films potential candidates for moisture absorbers for food packaging
Authors: Ebadi Zahra , Ghaisari Hamidreza , Tajeddin Behjat , Shekarforoush Seyed Shahram
Published: February 2021

This study was conducted to prepare starch‐based moisture absorbent pads from nanocellulose (NC) and nanowood (NW) particles using solution casting evaporation method and to evaluate their physical and mechanical properties at different thicknesses. The swelling degree (SD), water vapor permeability (WVP), tensile strength (TS), and elongation at break (EB), of prepared biofilms were measured. Structural properties of biofilms were evaluated by X‐ray diffraction (XRD) and scanning electron microscopy (SEM). Results indicated that two types of biopolymers showed the highest level of SD at thicknesses lower than 100 µm. The highest level of SD in the lowest time belonged to nanowood biofilm. Nanowood biofilms also showed highest WVP at lower thicknesses. Due to the highest EB and the lowest TS values, improvement was observed in mechanical properties of both nano biofilms. The high hydration capacity and WVP of low‐thickness NW films make it a promising candidate for developing biodegradable films with the potential to be used as a moisture‐absorbing pad in active food packaging.
Virtual sonographic hysteroscopy in assisted reproduction: A retrospective cost‐effectiveness analysis
Authors: Vitale Salvatore Giovanni , Laganà Antonio Simone , Török Péter , Lasmar Ricardo Bassil , Carugno Jose , Palumbo Marco , Tesarik Jan
Published: February 2021

Objective

To analyze the cost‐effectiveness of virtual sonographic hysteroscopy (VSH) performed before in vitro fertilization (IVF) (Scenario 1), frozen embryo transfer (Scenario 2), and oocyte donation (Scenario 3) attempts.

Methods

A retrospective analysis of data extracted from patients’ files was conducted. Before undergoing the assigned treatment, VSH was offered to all patients. Cost‐effectiveness was calculated on the basis of cost per live birth. The total cost was compared with a control group of patients who declined to have hysteroscopy before their treatment.

Results

A total of 292 women were involved. Virtual sonographic hysteroscopy was performed in 192 women. Conventional operative hysteroscopy was subsequently required in 34 of them (17.7%). Subsequent assisted reproduction attempts resulted in live birth in 111 women—34/69 (49.3%), 35/69 (50.7%), and 42/54 (77.8%) in Scenarios 1, 2, and 3, respectively. This compared favorably with 100 women who declined VSH, with live birth achieved in 15/39 (38.5%), 14/37 (37.8%), and 15/24 (62.5%) in Scenarios 1, 2, and 3, respectively. The overall cost‐effectiveness of VSH compared favorably with straightforward treatment performed without this test.

Conclusion

The overall cost‐effectiveness of treatment attempts carried out after previous VSH compared favorably with straightforward treatment performed without this test.
M‐wave and H‐reflex recruitment curves in boys and men
Authors: Piponnier Enzo , Ratel Sébastien , Chalchat Emeric , Bontemps Bastien , Bocock Olivia , Julian Valérie , Duclos Martine , Martin Vincent
Published: February 2021

The aim of the present study was to check whether the M‐wave and H‐reflex recruitment curves differ between prepubertal boys and men. Eleven boys (9–11 yr) and eleven men (18–35 yr) were magnetically stimulated at the tibial nerve in a prone position. M‐wave and H‐reflex maximal amplitudes (Hmax; Mmax; Hmax/Mmax), thresholds, regression slopes (Hslp; Mslp; Hslp/Mslp) were extracted from M‐wave and H‐reflex recruitment curves and compared between the two age groups. Overall, no significant difference in M‐wave and H‐reflex recruitment curve parameters was found between the two populations. Nevertheless, the size of the M‐wave associated with maximal H‐reflex amplitude was lower in boys as compared to men when expressed relative to maximal M‐wave amplitude (MHmax/Mmax: 0.18 ± 0.06 vs. 0.31 ± 0.13; p < .05). This result suggests that the development of peripheral nerve was completed in 9 to 11‐year‐old boys and did not affect the M‐wave and H‐reflex recruitment curves parameters. In neuromuscular function studies, it implies that Hmax/Mmax and Hslp/Mslp could be used indifferently to compare spinal motoneuron excitability between 9–11‐year‐old boys and men. Conversely, evoking H‐reflexes at a given percentage of Mmax may bias the comparison between boys and men.