bluuebunny/crossref_metadata_2025_split huggingface dataset:
Single‐Phase Formation of Rh2O3 Nanoparticles on h‐BN Support for Highly Controlled Methane Partial Oxidation to Syngas
Authors: Kim Younhwa , Kang Sungsu , Kang Dohun , Lee Kyung Rok , Song Chyan Kyung , Sung Jongbaek , Kim Ji Soo , Lee Hyunjoo , Park Jungwon , Yi Jongheop 
Published: September 2021

AbstractSingle‐phase formation of active metal oxides on supports has been vigorously pursued in many catalytic applications to suppress undesired reactions and to determine direct structure‐property relationships. However, this is difficult to achieve in nanoscale range because the effect of non‐uniform metal‐support interfaces becomes dominant in the overall catalyst growth, leading to the nucleation of various metastable oxides. Herein, we develop a supported single‐phase corundum‐Rh2O3(I) nanocatalyst by utilizing controlled interaction between metal oxide and h‐BN support. Atomic‐resolution electron microscopy and first‐principle calculation reveal that single‐phase formation occurs via uniform and preferential attachment of Rh2O3(I) (110) seed planes on well‐defined h‐BN surface after decomposition of rhodium precursor. By utilizing the Rh/h‐BN catalyst in methane partial oxidation, syngas is successfully produced solely following the direct route with keeping a H2/CO ratio of 2, which makes it ideal for most downstream chemical processes.
Corroles: The Hitherto Elusive Parent Macrocycle and its Metal Complexes
Authors: Kumar Amit , Yadav Pinky , Majdoub Mahmoud , Saltsman Irena , Fridman Natalia , Kumar Sachin , Kumar Anil , Mahammed Atif , Gross Zeev 
Published: September 2021

AbstractCorroles, macrocycles that owe their name to the cobalt‐chelating prosthetic group of vitamin B12 and share numerous features with the iron‐chelating porphyrin present in heme proteins/enzymes, constantly cross new boundaries ever since stable derivatives became easily accessible. Particularly important is the increasing utilization of corroles and the corresponding metal complexes for the benefit of mankind, in terms of new drug candidates for treating various diseases and as catalysts for sustainable energy relevant processes. One challenge is to gain access to the plain macrocycle, as to allow for full elucidation of the most fundamental properties of corroles. We have obtained the substituent‐free corrole by several surprising and conceptually different pathways. Selected features of the corresponding metal complexes are illuminated, for pointing towards unique phenomena that are anticipated to largely expand the horizon regarding their utilization for contemporary catalysis.
Aboriginal serrated and perforated shell artefacts from the Murray River, South Australia
Authors: ROBERTS AMY , WESTELL CRAIG , WILSON CHRISTOPHER , LANGLEY MICHELLE C. , MALLEE ABORIGINAL CORPORATION RIVER MURRAY AND , CORPORATION NGARRINDJERI ABORIGINAL 
Published: September 2021

ABSTRACTThis article describes three freshwater mussel shell artefacts recently documented for the Murray River in South Australia. These finds more than double the known examples of such artefacts from this region. Two of the modified shells are perforated, with the other serrated. The finely serrated item is a rare artefact and we have not located any similar published examples in Australia, although international correlates exist. The function/s and cultural significance of the objects are also considered in this paper. Hypotheses for the perforated finds include ornamentation, tool stringing and fibre scraping. Ornamentation, idle tinkering and food utensil use are considered as possible intended functions for the serrated artefact. Given the age range of the objects reported here (c. 6181–517 cal BP), together with other finds in the Murray Darling Basin, we tentatively suggest that shells have been a material resource used continually in this region for a range of purposes. However, as argued by other researchers, we concur that there has probably been infrequent identification and reporting of such shell artefacts. This is considered particularly likely given that our finds were recovered from relatively small scale excavation/coring and surface sampling efforts. As such, this paper attempts to raise awareness of this form of material culture in archaeological sequences.
Synthesis and antischistosomal activity of linker‐ and thiophene‐modified biaryl alkyl carboxylic acid derivatives
Authors: Peter Ventura Alejandra M. , Haeberlein Simone , Konopka Leonie , Obermann Wiebke , Grünweller Arnold , Grevelding Christoph G. , Schlitzer Martin 
Published: September 2021

AbstractSchistosomiasis is a neglected tropical disease caused by blood flukes of the genus Schistosoma and causes severe morbidity in infected patients. In 2018, 290.8 million people required treatment, and 200,000 deaths are reported per year. Treatment of this disease depends on a single drug, praziquantel (PZQ). However, in the past few years, reduced sensitivity of the parasites toward PZQ has been reported. Therefore, there is an urgent need for new drugs against this disease. In the past few years, we have focused on a new substance class called biaryl alkyl carboxylic acid derivatives, which showed promising antischistosomal activity in vitro. Structure–activity relationship (SAR) studies of the carboxylic acid moiety led to three promising carboxylic amides (morpholine, thiomorpholine, and methyl sulfonyl piperazine) with an antischistosomal activity down to 10 µM (morpholine derivative) and no cytotoxicity up to 100 µM. Here, we show our continued work on this substance class. We investigated, in extended SAR studies, whether modification of the linker and the thiophene ring could improve the antischistosomal activity. We found that the exchange of the alkyl linker by a pentadienyl or benzyl linker was tolerated and led to similar antischistosomal effects, whereas the exchange of the thiophene ring was not tolerated. Our data suggest that the thiophene ring is important for the antischistosomal activity of this compound class.
Gingival fenestration defect treated with gingivectomy and gingivoplasty: A case report with an 8‐year follow‐up
Authors: Kajimoto Natália de Campos , Buischi Yvonne de Paiva , Loomer Peter Michael , Pola Natália Marcumini , Nagata Maria José Hitomi , Bosco Alvaro Francisco 
Published: September 2021

AbstractIntroductionGingival fenestration (GF) is scarcely reported in the literature. We present a unique case of GF defect combined with gingivitis and altered passive eruption (APE).Case PresentationAn 18‐year‐old female patient with gingivitis, APE, and GF in the mandibular left central incisor presented for periodontal treatment. The gingival lesion was successfully treated with basic periodontal therapy gingivectomy, and gingivoplasty and resulted in an excellent aesthetic long‐term outcome. This case report shows its 8‐year clinical follow‐up.ConclusionThere are no earlier reports dealing with the use of gingivoplasty for the treatment of GF, as it is not the usual therapeutic intervention for these defects. Gingivoplasty proved to be effective in treating GF.Why is this case new information?

Available literature on gingival fenestration defects does not describe gingivectomy and gingivoplasty as a treatment of choice.
Gingivectomy and gingivoplasty proved to be effective in treating gingival fenestration defects.
What are the keys to successful management of this case?

Proper diagnosis.
What are the primary limitations to success in this case?

Gingival fenestration has been defined when the overlying gingiva is denuded, exposing the root to the oral cavity. However, in this case report, only the crown was exposed because the patient had altered passive eruption.
Trinuclear Cyanido‐Bridged [Cr2Fe] Complexes: To Be or not to Be a Single‐Molecule Magnet, a Matter of Straightness
Authors: Pichon Céline , Suaud Nicolas , Jubault Valentin , Duhayon Carine , Guihéry Nathalie , Sutter Jean‐Pascal 
Published: September 2021

AbstractTrinuclear systems of formula [{Cr(LN3O2Ph)(CN)2}2M(H2LN3O2R)] (M=MnII and FeII, LN3O2R stands for pentadentate ligands) were prepared in order to assess the influence of the bending of the apical M−N≡C linkages on the magnetic anisotropy of the FeII derivatives and in turn on their Single‐Molecule Magnet (SMM) behaviors. The cyanido‐bridged [Cr2M] derivatives were obtained by assembling trans‐dicyanido CrIII complex [Cr(LN3O2Ph)(CN)2]− and divalent pentagonal bipyramid complexes [MII(H2LN3O2R)]2+ with various R substituents (R=NH2, cyclohexyl, S,S‐mandelic) imparting different steric demand to the central moiety of the complexes. A comparative examination of the structural and magnetic properties showed an obvious effect of the deviation from straightness of the M−N≡C alignment on the slow relaxation of the magnetization exhibited by the [Cr2Fe] complexes. Theoretical calculations have highlighted important effects of the bending of the apical C−N−Fe linkages on both the magnetic anisotropy of the FeII center and the exchange interactions with the CrIII units.
Studies on The Application of The Paternò‐Büchi Reaction to The Synthesis of Novel Fluorinated Scaffolds
Authors: Gomez Fernandez Mario Andrés , Lefebvre Corentin , Sudau Alexander , Genix Pierre , Vors Jean‐Pierre , Abe Manabu , Hoffmann Norbert 
Published: September 2021

AbstractIn the context of new scaffolds obtained by photochemical reactions, Paternò‐Büchi reactions between heteroaromatic, trifluoromethylphenyl ketone and electron rich alkenes to give oxetanes are described. A comprehensive study has then been carried out on the reaction of aromatic ketones with fluorinated alkenes. Depending on the substitution pattern at the oxetane ring, a metathesis reaction is described as a minor side process to give mono fluorinated alkenes. Overall, this last reaction corresponds to a photo‐Wittig reaction and yield amid isosteres. In order to explain the uncommon regioselectivity of the Paternò‐Büchi reaction with these alkenes, electrostatic‐potential derived charges (ESP) have been determined. In a second computational study, the relative stabilities of the typical 1,4‐diradical intermediates of the Paternò‐Büchi reaction have been determined. The results well explain the regioselectivity. Further transformations of the oxetanes or previous functionalization of the fluoroalkenes open perspectives for oxetanes as core structures for biologically active compounds.
Enantiodivergent One‐Pot Synthesis of Axially Chiral Biaryls Using Organocatalyst‐Mediated Enantioselective Domino Reaction and Central‐to‐Axial Chirality Conversion
Authors: Koshino Seitaro , Taniguchi Tohru , Monde Kenji , Kwon Eunsang , Hayashi Yujiro 
Published: September 2021

AbstractEnantiodivergent one‐pot synthesis of biaryls was developed using a catalytic amount of a single chiral source. A domino organocatalyst‐mediated enantioselective Michael reaction and aldol condensation provided centrally chiral dihydronaphthalenes with excellent enantioselectivity, from which an enantiodivergent chirality conversion from central‐to‐axial chirality was achieved. Both enantiomers of biaryls were obtained with excellent enantioselectivity. All transformations can be conducted in a single reaction vessel. A plausible reaction mechanism for the enantiodivergence is proposed.
Multiscale conformational dynamics probed by time‐resolved circular dichroism from seconds to picoseconds
Authors: Hache François , Changenet Pascale 
Published: September 2021

AbstractTime‐resolved circular dichroism has been developed for a few decades to investigate rapid conformational changes in (bio)molecules. In our group, we have come up with several experimental set‐ups allowing us to study pico‐nanosecond local phenomena in molecular systems as well as much slower effects occurring in proteins and DNA in the folding processes. After an overview of the worldwide realizations in this domain, we present emblematic experiments that we have carried out, spanning time domain from picoseconds to seconds.
A Step toward NRF2‐DNA Interaction Inhibitors by Fragment‐Based NMR Methods
Authors: Brüschweiler Sven , Fuchs Julian E. , Bader Gerd , McConnell Darryl B. , Konrat Robert , Mayer Moriz 
Published: September 2021

AbstractThe NRF2 transcription factor is a key regulator in cellular oxidative stress response, and acts as a tumor suppressor. Aberrant activation of NRF2 has been implicated in promoting chemo‐resistance, tumor growth, and metastasis by activating its downstream target genes. Hence, inhibition of NRF2 promises to be an attractive therapeutic strategy to suppress cell proliferation and enhance cell apoptosis in cancer. Direct targeting of NRF2 with small‐molecules to discover protein‐DNA interaction inhibitors is challenging as it is a largely intrinsically disordered protein. To discover molecules that bind to NRF2 at the DNA binding interface, we performed an NMR‐based fragment screen against its DNA‐binding domain. We discovered several weakly binding fragment hits that bind to a region overlapping with the DNA binding site. Using SAR by catalogue we developed an initial structure‐activity relationship for the most interesting initial hit series. By combining NMR chemical shift perturbations and data‐driven docking, binding poses which agreed with NMR information and the observed SAR were elucidated. The herein discovered NRF2 hits and proposed binding modes form the basis for future structure‐based optimization campaigns on this important but to date ‘undrugged’ cancer driver.
Dual Loading of Doxorubicin and Magnetic Iron Oxide into PLA‐TPGS Nanoparticles: Design, in vitro Drug Release Kinetics, and Biological Effects on Cancer Cells
Authors: Phan Ke Son , Ha Phuong Thu , Do Huu Nghi , Nguyen Trung Anh , Bui Thuc Quang , Pham Hong Nam , Le Mai Huong , Le Thi Thu Huong 
Published: September 2021

AbstractThe multifunctional nano drug delivery system (MNDDS) has much revolutionized in cancer treatment, aiming to eliminate many disadvantages of conventional formulations. This paper herein proposes and demonstrates MNDDS inspired by poly(lactide)‐tocopheryl polyethylene glycol succinate (PLA‐TPGS) copolymer co‐loaded Doxorubicin and magnetic iron oxide nanoparticles (MIONs) with a 1 : 1 (w/w) optimal ratio. In vitro drug release kinetics of Doxorubicin from this nanosystem fitted best to the Weibull kinetic model and can be described by the classical Fickian diffusion mechanism under acidic pH conditions. The combination of MIONs and Doxorubicin in the PLA‐TPGS copolymer has maintained the fluorescence properties of Doxorubicin and good cell penetration, especially inside the nucleus and its vicinity. Moreover, different cell cycle profiles were observed in HeLa cell lines treated with MNDDSs.
Interplay of m6A and histone modifications contributes to temozolomide resistance in glioblastoma
Authors: Li Fuxi , Chen Siyun , Yu Jiaming , Gao Zhuoxing , Sun Zhangyi , Yi Yang , Long Teng , Zhang Chuanxia , Li Yuzhe , Pan Yimin , Qin Chaoying , Long Wenyong , Liu Qing , Zhao Wei 
Published: September 2021

AbstractBackgroundDespite the development of new treatment protocols for glioblastoma (GBM), temozolomide (TMZ) resistance remains a primary hindrance. Previous studies, including our study, have shown that aberrant N6‐methyladenosine (m6A) modification is implicated in GBM pathobiology. However, the roles and precise mechanisms of m6A modification in the regulation of TMZ resistance in GBM remain unclear.Methodsm6A individual‐nucleotide‐resolution cross‐linking and immunoprecipitation sequencing (miCLIP‐seq) was performed to identify m6A modification of transcripts in TMZ‐resistant and ‐sensitive tumors. To explore the role of METTL3 in TMZ resistance, TMZ‐resistant GBM cells were transfected with METTL3 shRNA or overexpression lentivirus and then assessed by cell viability, tumor sphere formation, and apoptosis assays. An intracranial GBM xenograft model was developed to verify the effect of METTL3 depletion during TMZ treatment in vivo. ATAC‐seq, ChIP‐qPCR, and dual‐luciferase reporter assays were carried out to verify the role of SOX4/EZH2 in the modulation of METTL3 expression upon TMZ treatment.ResultsWe demonstrated that TMZ treatment upregulated the expression of the m6A methyltransferase METTL3, thereby increasing m6A modification of histone modification‐related gene transcripts. METTL3 is required to maintain the features of GBM stem cells. When combined with TMZ, METTL3 silencing suppressed orthotopic TMZ‐resistant xenograft growth in a cooperative manner. Mechanistically, TMZ induced a SOX4‐mediated increase in chromatin accessibility at the METTL3 locus by promoting H3K27ac levels and recruiting RNA polymerase II. Moreover, METTL3 depletion affected the deposition of m6A on histone modification‐related gene transcripts, such as EZH2, leading to nonsense‐mediated mRNA decay. We revealed an important role of EZH2 in the regulation of METTL3 expression, which was via an H3K27me3 modification‐independent manner.ConclusionsOur findings uncover the fundamental mechanisms underlying the interplay of m6A RNA modification and histone modification in TMZ resistance and emphasize the therapeutic potential of targeting the SOX4/EZH2/METTL3 axis in the treatment of TMZ‐resistant GBM.
Physical layer secure key generation with nonlinear preprocessing of RSS for power constraint wireless networks
Authors: Sharma Ravindra , Upadhyay Raksha 
Published: September 2021

SummaryThere has been growing attention in physical layer security (PLS) techniques for wireless networks. PLS techniques are based on physical layer characteristics and are less computationally complex than traditional cryptographic approaches, which work on higher layers of networks. Physical layer key generation (PLKG) is one of the prominent key based PLS techniques that exploits reciprocity and randomness of wireless fading channel to establish secure communication between two transceivers. PLKG system consists of five stages as RSS measurement, its preprocessing, quantization and encoding, key reconciliation, and privacy amplification. Each stage has a substantial role in deciding the performance of PLKG system, but RSS preprocessing offers wide scope in performance improvement for the system. In this work, we propose PLKG system using a new class of preprocessing technique first time, which is nonlinear. We formulated the problem uniquely and considered two nonlinear techniques: nonlinear preprocessing using expander (NLPE) and nonlinear preprocessing using compressor (NLPC). We analyzed the performance of system using NLPE and NLPC and found NLPE is most suitable. Performance of the system is evaluated in terms of bit disagreement rate (BDR) and randomness of keys. Results show that NLPE performs extremely well, as compared with linear approach and without preprocessing approach, especially at low signal to noise ratio (SNR) range. Emerging wireless networks such as internet of things (IoT), centralized radio access network (CRAN), wireless sensor network (WSN), and so forth are being operated at lower transmission power with lightweight hardware. Hence, for such type of power constraint networks, proposed PLKG system with NLPE can be proven a perfect security solution.
Variation in parasite resistance of Arctic charr, Salvelinus alpinus, between and within sympatric morphs
Authors: Karvonen Anssi , Beck Samantha V. , Skúlason Skúli , Kristjánsson Bjarni K. , Leblanc Camille A. 
Published: September 2021

AbstractGenetic variation in resistance against parasite infections is a predominant feature in host–parasite systems. However, mechanisms maintaining genetic polymorphism in resistance in natural host populations are generally poorly known. We explored whether differences in natural infection pressure between resource‐based morphs of Arctic charr (Salvelinus alpinus) have resulted in differentiation in resistance profiles. We experimentally exposed offspring of two morphs from Lake Þingvallavatn (Iceland), the pelagic planktivorous charr (“murta”) and the large benthivorous charr (“kuðungableikja”), to their common parasite, eye fluke Diplostomum baeri, infecting the eye humor. We found that there were no differences in resistance between the morphs, but clear differences among families within each morph. Moreover, we found suggestive evidence of resistance of offspring within families being positively correlated with the parasite load of the father, but not with that of the mother. Our results suggest that the inherited basis of parasite resistance in this system is likely to be related to variation among host individuals within each morph rather than ecological factors driving divergent resistance profiles at morph level. Overall, this may have implications for evolution of resistance through processes such as sexual selection.
EPR, Magnetic, and Computational Characterization of Linear and Zigzag Ladder‐type Chains of Exchange Coupled Cu(II) Complexes with Picolinic and Dipicolinic Acid Ligands
Authors: Pérez Ana L. , Kemmerer Axel , Baggio Ricardo , Ramos Carlos A. , Dalosto Sergio D. , Passeggi Mario C. G. , Rizzi Alberto C. , Brondino Carlos D. 
Published: September 2021

AbstractWe report magnetic, EPR, and computational studies on two representative examples of structurally well‐characterized one dimension (1D) molecular systems: the copper complexes catena‐[bis(μ‐pyridine‐2‐carboxylato)‐copper dihydrate] and catena‐[(μ2‐pyridine‐2,6‐dicarboxylato)‐diaqua‐copper(II)], hereafter 1 and 2, respectively. Experimental and theoretical results confirmed that the structural chains in both compounds behave as magnetic chains in which the copper ions are weakly coupled by isotropic exchange. Magnetic susceptibility measurements of 1 suggested that the copper ions are antiferromagnetically coupled whereas EPR measurements suggested ferromagnetic coupling at temperature above 100 K which becomes antiferromagnetic at low temperatures. Computational calculations would indicate that the ferromagnetic‐antiferromagnetic change may be due to dCu−Oap shortening on lowering temperature temperature (a fact that was observed experimentally by XRD at low temperatures), which redistributes the small Cu(II) unpaired spin density delocalized on the apical ligand to copper. The 1D magnetic behavior of the zigzag ladder chain of 2 is less detectable than that of the single chain of 1. Magnetic susceptibility measurements in conjunction with computational calculations showed that the pathways that give rise to the 1D ladder transmit ferromagnetic exchange interactions with different strengths, with the stronger interaction being transmitted along the rungs. The role of the weaker exchange interactions transmitted along the rails on the magnetic dimensionality of 2 is analyzed.
Efficient Conversion of Biomass Derived Levulinic Acid to γ‐Valerolactone Using Hydrosilylation
Authors: Garg Nitish K. , Schmalz Veronika , Johnson Magnus T. , Wendt Ola F. 
Published: September 2021

AbstractConverting biomass into value‐added chemicals is of significant interest and we report an efficient hydrosilylation to convert levulinic acid to γ‐valerolactone using cost‐effective silanes such as PMHS and TMDS with B(C6F5)3 as catalyst. This metal free methodology works at room temperature reaching TONs and TOFs up to 16000 and 2000 h−1. Insights into the reaction mechanism are reported.