bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Tillage Practices and Nitrogen Sources on Nitrogen Availability and Uptake of Rice
Authors: Nagarjuna Polagani , Venkateswarlu B. , Sreerekha M. , Prasad P. R. K. , Jayalalitha K. 
Published: June 2021

Aim: Evaluation of tillage practices and nitrogen sources on nitrogen availability in soil and nitrogen uptake of rice
Study design: The experiment was laid out in strip-plot design with different tillage practices in horizontal strip and different nitrogen sources in vertical strip and was replicated thrice.
Place and duration of study: The field experiment was conducted during the kharif season of 2019 and 2020 at the Agricultural College Farm, Bapatla, ANGRAU, Lam, Guntur, Andhra Pradesh.
Methodology: The experiment was performed with twenty treatments in strip-plot design. The horizontal strip comprised four different tillage practices and vertical strip with five different nitrogen sources. Rice variety “BPT-5204” was taken as the test variety. Observations of the crop and soil during the experimentation were recorded at regular intervals. The significance of the treatment impact was examined by the test.
Results: Among tillage practices, higher nitrogen uptake by rice grain (85.30 and 86.96 Kg ha-1) and straw (41.21 and 41.91 Kg ha-1) during 2019-20 and 2020-21, respectively was recorded in conventional tillage (T4) which was found statistically on a par with dry seeding on puddled soil (T1) (81.15 and 82.79 Kg ha-1, 38.59 and 39.20 Kg ha-1 during 2019-20 and 2020-21, respectively) and significantly superior over reduced tillage (T2) and minimum tillage (T3). Among nitrogen source, application of 50% STBN through fertilizer + 50% N through cured poultry manure (N5) registered the highest uptake of nitrogen in grain and straw (85.38 and 87.02 Kg ha-1. 42.09 and 42.76 Kg ha-1 during 2019-20 and 2020-21, respectively) and it was found significantly on a par with 75% STBN through fertilizer + 25% N through cured poultry manure (N4) and significantly superior over 50% STBN through fertilizer + 50% N through FYM (N3), 75% STBN through fertilizer + 25% N through FYM (N2), and 100% STBN through fertilizer (N1) treatment.
Renoprotective effects of levosimendan on acute kidney injury following cardiac arrest via anti‐inflammation, anti‐apoptosis, and ERK activation
Authors: Tian Lei , Wang Shiwei , Zhao Li , Lu Xiaoye , Zhu Changqing , Gong Hao , Yang Weiqiang 
Published: June 2021

ATP‐sensitive potassium channels (KATPs) have protective effects in ischemia–reperfusion‐induced injuries and can be activated by levosimendan. This study investigated the effects of levosimendan on renal injury, inflammation, apoptosis, and survival in a rat model of acute kidney injury (AKI) following cardiac arrest (CA) and cardiopulmonary resuscitation (CPR). Rats underwent a 5‐min asphyxia‐based CA and resuscitation. The rats were treated with levosimendan after successful resuscitation. Renal functions, histological changes, inflammatory responses, and apoptosis were examined. NRK‐52E cells treated by hypoxia/reoxygenation (H/R) were used to establish an in vitro CA‐CPR model. Rats in the CA‐induced AKI group had a low survival rate and increased levels of creatinine, blood urea nitrogen, and proinflammatory cytokines, as well as increased tubular injury. These results were significantly reversed after treatment with levosimendan. Levosimendan downregulated the expression of the apoptosis‐related proteins Bax, cleaved caspase‐3, and cleaved caspase‐9, as well as upregulated Bcl‐2 and p‐ERK expression in vivo and in vitro. Thus, our data suggest that levosimendan reduces mortality and AKI following CA and CPR via suppression of inflammation and apoptosis, and activation of ERK signaling.
Polymeric Micro/Nanomotors and Their Biomedical Applications
Authors: Liang Ziying , Tu Yingfeng , Peng Fei 
Published: June 2021

AbstractSince their naissance in the 2000s, various micro or nanomotors with powerful functions have been proposed. Among them, polymer‐based micro or nanomotors stand out for the easy processing and facile functionalization, holding immense potential for bioapplications. In this review, fabrication of polymer‐based micro or nanomotors and their applications in biomedical areas are covered. Classic manufacturing approaches as well as cutting‐edge techniques are discussed with representative works highlighted. Current challenges and future prospects are presented in the hope of pointing new research directions to facilitate practical translations of micro/nanomotors.
Remote Site‐Selective Radical C(sp3)−H Monodeuteration of Amides using D2O
Authors: Wang Lin , Xia Yong , Derdau Volker , Studer Armido 
Published: June 2021

AbstractSite‐selective incorporation of deuterium into biologically active compounds is of high interest in pharmaceutical industry. We present a mild and environmentally benign metal‐free method for the remote selective radical C−H monodeuteration of aliphatic C−H bonds in various amides with inexpensive heavy water (D2O) as the deuterium source. The method uses the easily installed N‐allylsulfonyl moiety as an N‐radical precursor that generates the remote C‐radical via site‐selective 1,5‐ or 1,6‐hydrogen atom transfer (HAT). Methyl thioglycolate, that readily exchanges its proton with D2O, serves as the radical deuteration reagent and as a chain‐carrier. The highly site‐selective monodeuteration has been applied to different types of unactivated sp3‐C−H bonds and also to the deuteration of C−H bonds next to heteroatoms. The potential utility of this method is further demonstrated by the site‐selective incorporation of deuterium into natural product derivatives and drugs.
Photoinduced Electron‐Transfer (PIET) Strategy for Selective Adsorption of CO2 over C2H2 in a MOF
Authors: Cai Li‐Zhen , Yao Zi‐Zhu , Lin Shu‐Juan , Wang Ming‐Sheng , Guo Guo‐Cong 
Published: June 2021

AbstractSimilarities in sizes, shapes, and physical properties between carbon dioxide (CO2) and acetylene (C2H2) make it a great challenge to separate the major impurity CO2 from products in C2H2 production. The use of porous materials is an appealing path to replace current very costly and energy‐consuming technologies, such as solvent extraction and cryogenic distillation; however, high CO2/C2H2 uptake ratio with minor adsorption of C2H2 at standard pressure was only unexpectedly observed in scarce examples in recent years although the related research started early at 1950s, and general design strategies to realize this aim are still absent. This work has successfully developed an efficient PIET strategy and obtained the second highest CO2/C2H2 adsorption ratio for porous materials in a proof‐of‐concept MOF with a photochromism‐active bipyridinium zwitterion. An unprecedented photocontrollable gate effect, owing to change of interannular dihedral after photoinduced generation of radical species, was also observed for the first time. These findings will inspire design and synthesis of porous materials for high efficient gas adsorption and separation.
Unusual Surface Texture, Dimensions and Morphology Variations of Chiral and Single Crystals**
Authors: Singh Vivek , Houben Lothar , Shimon Linda J. W. , Cohen Sidney R. , Golani Ofra , Feldman Yishay , Lahav Michal , van der Boom Milko E. 
Published: June 2021

AbstractWe demonstrate here a unique metallo‐organic material where the appearance and the internal crystal structure are in contradiction. The egg‐shaped (ovoid) crystals have a brain‐like texture. Although these micro‐sized crystals are monodispersed; like fingerprints their grainy surfaces are never exactly alike. Remarkably, our X‐ray and electron diffraction studies unexpectedly revealed that these structures are single‐crystals comprising a continuous coordination network of two differently shaped homochiral channels. By using the same building blocks under different reaction conditions, a rare series of crystals have been obtained that are uniquely rounded in their shape. In stark contrast to the brain‐like crystals, these isostructural and monodispersed crystals have a comparatively smooth appearance. The sizes of these crystals vary by several orders of magnitude.
Catalyst‐ and Solvent‐Free Synthesis of a Chemically Stable Aza‐Bridged Bis(phenanthroline) Macrocycle‐Linked Covalent Organic Framework
Authors: Jiang Yi , Jung Hyeonjung , Joo Se Hun , Sun Qi Kun , Li Changqing , Noh Hyuk‐Jun , Oh Inseon , Kim Yu Jin , Kwak Sang Kyu , Yoo Jung‐Woo , Baek Jong‐Beom 
Published: June 2021

AbstractDeveloping new linkage‐based covalent organic frameworks (COFs) is one of the major topics in reticular chemistry. Electrically conductive COFs have enabled applications in energy storage and electrochemical catalysis, which are not feasible using insulating COFs. Despite significant advances, the construction of chemically stable conductive COFs by the formation of new linkages remains relatively unexplored and challenging. Here we report the solvent‐ and catalyst‐free synthesis of a two‐dimensional aza‐bridged bis(phenanthroline) macrocycle‐linked COF (ABBPM‐COF) from the thermally induced poly‐condensation of a tri‐topic monomer and ammonia gas. The ABBPM‐COF structure was elucidated using multiple techniques, including X‐ray diffraction analysis combined with structural simulation, revealing its crystalline nature with an ABC stacking mode. Further experiments demonstrated its excellent chemical stability in acid/base solutions. Electrical‐conductivity measurements showed that the insulating ABBPM‐COF becomes a semiconducting material after exposure to iodine vapor.
Nickel‐Catalyzed Regioselective Alkenylarylation of γ,δ‐Alkenyl Ketones via Carbonyl Coordination
Authors: Dhungana Roshan K. , Aryal Vivek , Niroula Doleshwar , Sapkota Rishi R. , Lakomy Margaret G. , Giri Ramesh 
Published: June 2021

AbstractWe disclose a nickel‐catalyzed reaction, which enabled us to difunctionalize unactivated γ,δ‐alkenes in ketones with alkenyl triflates and arylboronic esters. The reaction was made feasible by the use of 5‐chloro‐8‐hydroxyquinoline as a ligand along with NiBr2⋅DME as a catalyst and LiOtBu as base. The reaction proceeded with a wide range of cyclic, acyclic, endocyclic and exocyclic alkenyl ketones, and electron‐rich and electron‐deficient arylboronate esters. The reaction also worked with both cyclic and acyclic alkenyl triflates. Control experiments indicate that carbonyl coordination is required for the reaction to proceed.
An elevated anxiety level among prepubertal autistic boys with non‐treatment‐seeking functional gastrointestinal disorders: A case–control study
Authors: Wong Oscar W. H. , Lam Angela M. W. , Lai Kelly Y. C. , Ma Suk Ling , Hung Se Fong , Chan Sandra , Wong Sunny , Leung Patrick W. L. 
Published: June 2021

AbstractChildren with autism commonly suffer from comorbid functional gastrointestinal disorders (FGID) and anxiety. The raised prevalence of both conditions in autism suggests complex reciprocal relationships, which are seldom explored in non‐treatment‐seeking FGID. The relationships between subtypes of FGID and anxiety are also unclear. This study recruited boys with autism and age‐matched typically developing (TD) boys, aged 4–11 years, who were not actively seeking help for gastrointestinal problems. Their parents completed the Rome IV Diagnostic Questionnaires for Pediatric FGID. Four groups of children with and without autism/FGID were identified and compared on their anxiety level using the Spence children's anxiety scale. In 69 boys with autism and 69 age‐matched TD boys, FGID were identified in 22 and 16 boys, respectively. ANCOVA demonstrated a significant interaction effect of autism and FGID on anxiety (F[1, 129] = 5.43, p = 0.021), while conditional logistic regression identified an interaction effect of autism and anxiety on the odds of FGID (OR 1.038, 95% CI 1.002–1.075, p = 0.038). Explorative post hoc analysis showed higher anxiety in functional nausea and vomiting disorder (p = 0.033) and functional abdominal pain disorder (p = 0.029) among boys with autism than TD boys with the same respective subtypes of FGID. In summary, among prepubertal boys with autism, the presence of FGID that are non‐treatment‐seeking in nature, has a significantly stronger association with higher levels of anxiety than TD boys. The strength of association may be more prominent in subtypes of FGID. Possible pathomechanisms including the underlying microbiota spectra and inflammatory paths should be explored in future studies.Lay summaryAnxiety and gastrointestinal problems are common symptoms in autism. Given that gut health could be linked to emotions, their association in young boys with autism was studied. The presence of nausea vomiting, or abdominal pain were associated with raised anxiety among boys with autism, yet this was not observed in typically developing boys. This suggests that anxiety among autistic children could be partly explained by the presence of FGID.
Impact of Pore Size and Defects on the Selective Adsorption of Acetylene in Alkyne‐Functionalized Nickel(II)‐Pyrazolate‐Based MOFs
Authors: Afshariazar Farzaneh , Morsali Ali , Sorbara Simona , Padial Natalia M. , Roldan‐Molina Esther , Oltra J. Enrique , Colombo Valentina , Navarro Jorge A. R. 
Published: June 2021

AbstractC2H2/CO2 separation is a highly challenging process as a consequence of their similar physicochemical properties. In this work we have explored, by static and dynamic gas sorption techniques and computational modelling, the suitability of a series of two isoreticular robust Ni(II)pyrazolate‐based MOFs, bearing alkyne moieties on the ligand backbones, for C2H2/CO2 separation. The results are consistent with high adsorption capacity and selectivity of the essayed systems towards C2H2 molecules. Furthermore, a post‐synthetic treatment with KOH ethanolic solution gives rise to linker vacancy defects and incorporation of extraframework potassium ions. Creation of defects is responsible for increased adsorption capacity for both gases, however, strong interactions of the cluster basic sites and extraframework potassium cations with CO2 molecules are responsible for a lowering of C2H2 over CO2 selectivity.
Managing Experimental 3D Structures in the Beyond‐Rule‐of‐5 Chemical Space: The Case of Rifampicin
Authors: Ermondi Giuseppe , Lavore Francesca , Vallaro Maura , Tiana Guido , Vasile Francesca , Caron Giulia 
Published: June 2021

AbstractThe beyond‐Rule‐of‐5 (bRo5) chemical space is a source of new oral drugs and includes large and flexible compounds. Because of their size and conformational variability, bRo5 molecules assume different privileged conformations in the compartments of human body, i. e., they can exhibit chameleonic properties. The elucidation of the ensemble of 3D structures explored by such molecules under different conditions is therefore critical to check the role played by chameleonicity to modulate cell permeability. Here we characterized the conformational ensembles of rifampicin, a bRo5 drug, in polar and nonpolar solvents and in the solid state. We performed NMR experiments, analyzed their results with a novel algorithm and set‐up a pool of ad hoc in silico strategies to investigate crystallographic structures retrieved from the CSD. Moreover, a polarity descriptor often related to permeability (SA‐3D‐PSA) was calculated for all the conformers and its variation with the environment analyzed. Results showed that the conformational behavior of rifampicin in solution and in the solid state is not superposable. The identification of dynamic intramolecular hydrogen bonds can be assessed by NMR spectroscopy but not by X‐ray structures. Moreover, SA‐3D‐PSA revealed that dynamic IMHBs do not provide rifampicin with chameleonic properties. Overall, this study highlights that the peculiarity of rifampicin, which is cell permeable probably because of the presence of static IMHBs but is devoid of any chameleonic behavior, can be assessed by a proper analysis of experimental 3D structures.
Fluorinated α‐Diimine Nickel Mediated Ethylene (Co)Polymerization
Authors: Hu Xiaoqiang , Zhang Yixin , Li Baixiang , Jian Zhongbao 
Published: June 2021

AbstractFluorine substituents in transition metal catalysts are of great importance in olefin polymerization catalysis; however, the comprehensive effect of fluorine substituents is elusive in seminal late transition metal α‐diimine catalytic system. In this contribution, fluorine substituents at various positions (ortho‐, meta‐, and para‐F) and with different numbers (Fn; n=0, 1, 2, 3, 5) were installed into the well‐defined N‐terphenyl amine and thus were studied for the first time in the nickel α‐diimine promoted ethylene polymerization and copolymerization with polar monomers. The position of the fluorine substituent was particularly crucial in these polymerization reactions in terms of catalytic activity, polymer molecular weight, branching density, and incorporation of polar monomer, and thus a picture on the fluorine effect was given. As a notable result, the ortho‐F substituted α‐diimine nickel catalyst produced highly linear polyethylenes with an extremely high molecular weight (Mw=8703 kDa) and a significantly low degree of branching of 1.4/1000 C; however, the meta‐F and/or para‐F substituted α‐diimine nickel catalysts generated highly branched (up to 80.2/1000 C) polyethylenes with significantly low molecular weights (Mw=20‐50 kDa).
Rigid and Compact Binuclear Bis‐hydrated Gd‐complexes as High Relaxivity MRI Agents
Authors: Leone Loredana , Guarnieri Luca , Martinelli Jonathan , Sisti Massimo , Penoni Andrea , Botta Mauro , Tei Lorenzo 
Published: June 2021

AbstractThe first binuclear Gd‐complex of the 12‐membered pyridine‐based polyaminocarboxylate macrocyclic ligand PCTA was synthesized by C−C connection of the pyridine units through two different synthetic procedures. A dimeric AAZTA‐ligand was also synthesized with the aim to compare the relaxometric results or the two ditopic Gd‐complexes. Thus, the 1H relaxometric study on [Gd2PCTA2(H2O)4] and on [Gd2AAZTA2(H2O)4]2− highlighted the remarkable rigidity and compactness of the two binuclear complexes, which results in molar relaxivities (per Gd), at 1.5 T and 298 K of ca. 12–12.6 mM−1 s−1 with an increase of ca. 80 % at 1.5 T and 298 K (+70 % at 310 K) with respect to the corresponding mononuclear complexes.
Building an Iron Chromophore Incorporating Prussian Blue Analogue for Photoelectrochemical Water Oxidation
Authors: Ghobadi T. Gamze Ulusoy , Ghobadi Amir , Demirtas Merve , Buyuktemiz Muhammed , Ozvural Kubra N. , Yildiz Elif Akhuseyin , Erdem Emre , Yaglioglu H. Gul , Durgun Engin , Dede Yavuz , Ozbay Ekmel , Karadas Ferdi 
Published: June 2021

AbstractInvited for the cover of this issue is the Ferdi Karadas and Ekmel Ozbay groups at Bilkent University and co‐workers. The image presents an utopic city in Iron Age, which is powered by an iron photosensitizer that bridges semiconductor buildings (TiO2 nanowires) and the catalyst (cobalt site). Read the full text of the article at 10.1002/chem.202100654.
C=C Bond Oxidative Cleavage of BODIPY Photocages by Visible Light
Authors: Xu Youwei , Lin Shanmeng , He Rongkun , Zhang Yichuan , Gao Quan , Ng Dennis K. P. , Geng Jin 
Published: June 2021

AbstractPhotocages for protection and the controlled release of bioactive compounds have been widely investigated. However, the vast majority of these photocages employ the cleavage of single bonds and high‐energy ultraviolet light. The construction of a photoactivation system that uses visible light to cleave unsaturated bonds still remains a challenge. Herein, we report a regioselective oxidative cleavage of C=C bonds from a boron‐dipyrrolemethene (BODIPY)‐based photocage by illumination at 630 nm, resulting in a free aldehyde and a thiol fluorescent probe. This strategy was demonstrated in live HeLa cells, and the generated α‐formyl‐BODIPY allowed real‐time monitoring of aldehyde release in the cells. In particular, it is shown that a mannose‐functionalized photocage can target HepG2 cells.
PtM/MxBy (M=Ni, Co, Fe) Heterostructured Nanobundles as Advanced Electrocatalyst for Hydrogen Evolution Reaction
Authors: Yuan Mengyu , Xu Hui , Wang Cheng , Wang Yong , Wang Yuan , Wang Xiaomei , Du Yukou 
Published: June 2021

AbstractOptimizing the electronic and synergistic effect of hybrid electrocatalysts based on Pt and Pt‐based nanocatalysts is of tremendous importance towards a superior hydrogen evolution performance under both acidic and alkaline conditions. However, developing an ideal Pt‐based hydrogen evolution reaction (HER) electrocatalyst with moderated electronic structure as well as strong synergistic effect is still a challenge. Herein, we fabricated boron (B)‐doped PtNi nanobundles by a two‐step method using NaBH4 as the boron source to obtain PtNi/Ni4B3 heterostructures with well‐defined nanointerfaces between PtNi and Ni4B3, achieving an enhanced catalytic HER performance. Especially, the PtNi/Ni4B3 nanobundles (PtNi/Ni4B3 NBs) can deliver a current density of 10 mA cm−2 at the overpotential of 14.6 and 26.5 mV under alkaline and acidic media, respectively, as well as outstanding electrochemical stability over 40 h at the current density of 10 mA cm−2. Remarkably, this approach is also universal for the syntheses of PtCo/Co3B and PtFe/Fe49B with outstanding electrocatalytic HER performance.
Safe chemistry lessons – the safety assessment of maillard reactions of the formation of the flavours from roasted pork and popcorn
Authors: Klemeyer Horst 
Published: June 2021

AbstractDie Bildung von Braten‐ und Röstaromen ist eine wesentliche Facette des Garungsprozesses menschlicher Nahrung. Diese Aromen wirken auf Menschen attraktiv und können Appetit auslösen. Werden Braten‐ und Röstaromen im Schülerexperiment hergestellt, kann das Interesse der Schülerinnen und Schüler für ihren Chemieunterricht gesteigert werden. In dieser Arbeit sind die für das Aroma von Schweinebraten und von Popcorn verantwortlichen Stoffe mit ihren Eigenschaften beschrieben. Danach wird aufgezeigt, dass es sich bei den Gerüchen um Spurenverbindungen handelt, die aufgrund der geringen Konzentration keine Auswirkung auf die menschliche Gesundheit haben können.