bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient CO2 Electroreduction on Ag2S Nanodots Modified CdS Nanorods as Cooperative Catalysts
Authors: Cheng Ling , Wang Yating , Li Yuhang , Shen Yi , Zhen Yue , Xing Zhanqi , Lin Liwan , Chen Aiping , Zhu Yihua , Li Chunzhong 
Published: December 2020

AbstractCdS nanorods have been regarded as a promising candidate for electrocatalytic CO2 reduction compared with other chalcogenide catalysts, owing to the high Faradaic efficiency for producing CO in aqueous electrolyte. Unfortunately, the CO generation rate of the bare CdS is relatively low due to the poor intrinsic activity. In this work, we modify the surface of CdS nanorods by Ag2S nanodots to promote the CO2 reduction activity. With 5 wt % loading of Ag2S nanodots, we achieve the highest CO partial current density of 10.6 mA cm−2 at an applied potential of −1.1 V vs RHE, 11 % and 93 % enhancement compared to the separately synthesized CdS and Ag2S, respectively. When using flow cell to accelerate the CO2 mass transfer, the cooperative catalyst realizes ∼95 % Faradaic efficiency for C1 products with a fast CO2 reduction rate at a current density of 200 mA cm−2.
Exploratory N‐Protecting Group Manipulation for the Total Synthesis of Zwitterionic Shigella sonnei Oligosaccharides
Authors: Dhara Debashis , Mulard Laurence A. 
Published: December 2020

AbstractShigella sonnei surface polysaccharides are well‐established protective antigens against this major cause of diarrhoeal disease. They also qualify as unique zwitterionic polysaccharides (ZPSs) featuring a disaccharide repeating unit made of two 1,2‐trans linked rare aminodeoxy sugars, a 2‐acetamido‐2‐deoxy‐l‐altruronic acid (l‐AltpNAcA) and a 2‐acetamido‐4‐amino‐2,4,6‐trideoxy‐d‐galactopyranose (AAT). Herein, the stereoselective synthesis of S. sonnei oligosaccharides comprising two, three and four repeating units is reported for the first time. Several sets of up to seven protecting groups were explored, shedding light on the singular conformational behavior of protected altrosamine and altruronic residues. A disaccharide building block equipped with three distinct N‐protecting groups and featuring the uronate moiety already in place was designed to accomplish the iterative high yielding glycosylation at the axial 4‐OH of the altruronate component and achieve the challenging full deprotection step. Key to the successful route was the use of a diacetyl strategy whereby the N‐acetamido group of the l‐AltpNAcA is masked in the form of an imide.
Coordination Behavior of a P4‐Butterfly Complex towards Transition Metal Lewis Acids: Preservation versus Rearrangement
Authors: Müller Julian , Scheer Manfred 
Published: December 2020

AbstractThe reactivity of the P4 butterfly complex [{Cp’’’Fe(CO)2}2(μ,η1:1‐P4)] (1, Cp’’’=η5‐C5H2tBu3) towards divalent Co, Ni and Zn salts is investigated. The reaction with the bromide salts leads to [{Cp’’’Fe(CO)2}2(μ3,η2:1:1‐P4){MBr2}] (M=Co (2Co), Ni (2Ni), Zn (2Zn)) in which the P4 butterfly scaffold is preserved. The use of the weakly ligated Co complex [Co(NCCH3)6][SbF6]2, results in the formation of [{(Cp’’’Fe(CO)2)2(μ3,η4:1:1‐P4)}2Co][SbF6]3 (3), which represents the second example of a homoleptic‐like octaphospha‐metalla‐sandwich complex. The formation of the threefold positively charged complex 3 occurs via redox processes, which among others also enables the formation of [{Cp’’’Fe(CO)2}4(μ5,η4:1:1:1:1‐P8){Co(CO)2}][SbF6] (4), bearing a rare octaphosphabicyclo[3.3.0]octane unit as a ligand. On the other hand, the reaction with [Zn(NCCH3)4][PF6]2 yields the spiro complex [{(Cp’’’Fe(CO)2)2(μ3,η2:1:1‐P4)}2Zn][PF6]2 (5) under preservation of the initial structural motif.
Structure‐Based Drug Design of Phenazopyridine Derivatives as Inhibitors of Rev1 Interactions in Translesion Synthesis
Authors: McPherson Kerry Silva , Zaino Angela M. , Dash Radha C. , Rizzo Alessandro A. , Li Yunfeng , Hao Bing , Bezsonova Irina , Hadden M. Kyle , Korzhnev Dmitry M. 
Published: December 2020

AbstractRev1 is a protein scaffold of the translesion synthesis (TLS) pathway, which employs low‐fidelity DNA polymerases for replication of damaged DNA. The TLS pathway helps cancers tolerate DNA damage induced by genotoxic chemotherapy, and increases mutagenesis in tumors, thus accelerating the onset of chemoresistance. TLS inhibitors have emerged as potential adjuvant drugs to enhance the efficacy of first‐line chemotherapy, with the majority of reported inhibitors targeting protein‐protein interactions (PPIs) of the Rev1 C‐terminal domain (Rev1‐CT). We previously identified phenazopyridine (PAP) as a scaffold to disrupt Rev1‐CT PPIs with Rev1‐interacting regions (RIRs) of TLS polymerases. To explore the structure‐activity relationships for this scaffold, we developed a protocol for co‐crystallization of compounds that target the RIR binding site on Rev1‐CT with a triple Rev1‐CT/Rev7R124A/Rev3‐RBM1 complex, and solved an X‐ray crystal structure of Rev1‐CT bound to the most potent PAP analogue. The structure revealed an unexpected binding pose of the compound and informed changes to the scaffold to improve its affinity for Rev1‐CT. We synthesized eight additional PAP derivatives, with modifications to the scaffold driven by the structure, and evaluated their binding to Rev1‐CT by microscale thermophoresis (MST). Several second‐generation PAP derivatives showed an affinity for Rev1‐CT that was improved by over an order of magnitude, thereby validating the structure‐based assumptions that went into the compound design.
Regularized Stokes Immersed Boundary Problems in Two Dimensions: Well‐Posedness, Singular Limit, and Error Estimates
Authors: Tong Jiajun 
Published: December 2020

AbstractInspired by the numerical immersed boundary method, we introduce regularized Stokes immersed boundary problems in two dimensions to describe regularized motion of a 1‐D closed elastic string in a 2‐D Stokes flow, in which a regularized δ‐function is used to mollify the flow field and singular forcing. We establish global well‐posedness of the regularized problems and prove that as the regularization parameter diminishes, string dynamics in the regularized problems converge to that in the Stokes immersed boundary problem with no regularization. Viewing the unregularized problem as a benchmark, we derive error estimates under various norms for the string dynamics. Our rigorous analysis shows that the regularized problems achieve improved accuracy if the regularized δ‐function is suitably chosen. This may imply potential improvement in the numerical method, which is worth further investigation. © 2020 Wiley Periodicals LLC
A scalable parallel algorithm for building web directories
Authors: Seshadri Karthick , Maruthappan Aswin , Sundar Raman Mukunthapriya 
Published: December 2020

SummaryWeb directories like Wikipedia and Open Directory Mozilla facilitate efficient information retrieval (IR) of web documents from a huge web corpus. Maintenance of these web directories is understandably a difficult task that requires manual curation by human editors or semi‐automated mechanisms. Research on parallel algorithms for the automated curation of these web directories will be beneficial to the IR domain. Hence, in this article, we propose a parallel algorithm for automatically creating web directories from a corpus of web‐documents. We have used centrality‐based techniques to split the corpus into fine‐grained clusters and subsequently an agglomeration based on locality sensitive hashing to identify coarse‐grained clusters in the web‐directory. Experimental results show that the algorithm generates meaningful hierarchies of the input corpus as measured by cluster‐validity indices, like F‐measure, rand index, and cluster purity. The algorithm achieves a significant speedup and scales well both with the number of processors and the size of the input corpus.
An efficient shortest path routing on the hypercube with blocking/faulty nodes
Authors: Arabpour Niasari Mehrdad , Qiu Ke 
Published: December 2020

SummaryWe investigate fault‐tolerant shortest path problem in the hypercube between two nodes where some nodes are faulty (or blocked) and thus cannot be used in routing. Previously, several similar problems were studied where proposed algorithms are distributed and local‐information‐based, that is, each node in the network knows only its neighbor's status (faulty or not) and they also look for optimal or near‐optimal paths. There have been studies that established some sufficient conditions for these paths to exist. Since these conditions are only sufficient, there could be shortest paths that will be missed by these conditions. We study the problem under the assumption that for two given nodes, a source node s, a target node t, only s requires to have a global information of the network in order to find a shortest path to t, should it exist. A shortest path is defined as the Hamming distance between s and t. This problem can be solved by trivial algorithms. The first is to try all possible paths. In an n‐dimensional hypercube with 2n vertices, this method would cost at least n! time. Another method is to perform a standard shortest path finding algorithm, which would require at least 2n time. A routing algorithm has been previously developed which is efficient in certain situations. However, in the worst case, its running time could be exponential in the hypercube dimension. We propose an efficient algorithm with running time of O(n3m2), polynomial in n, the hypercube dimension, and m, number of blocking nodes. We gain our efficiency by reducing the routing problem to a permutation problem which can be solved using inclusion‐exclusion principle. We finally use dynamic programming technique to optimally count the terms. With the proposed algorithm, not only can we find a shortest path, if such a path does exist, but we can also count all possible shortest paths.
The efficacy of polyether‐ether‐ketone wire as a retainer following orthodontic treatment
Authors: Kadhum Ammar Salim , Alhuwaizi Akram Faisal 
Published: December 2020

AbstractObjectivesTo investigate the efficacy of polyether‐ether‐ketone (PEEK) wire as a fixed orthodontic retainer, by comparing its performance to other retainer wires and optimizing its adhesion to composite bonding materials.Materials and methodsRetainer wires of 15 mm segments were used, PEEK wires were prepared in cylindrical form with 0.8 mm diameter, and had two surface treatments namely air‐abrasion and conditioning with adhesive system. Three different metallic retainer wires were used for comparison and three tests were performed; two tests measured debonding force and associated wire deflection from acrylic blocks and bovine teeth and one test for pull‐out force. To test debonding force, a vertically directed compressive force was applied to the retainer wires bonded to the acrylic blocks and bovine teeth, while for pull‐out test; a vertically directed tensile force detached the retainer wire.ResultsIn both debonding tests, PEEK wires (regardless the surface treatment) had non‐significant difference when compared to each other, or to the other metallic wires, except the dead‐soft coaxial wire group. The dead‐soft coaxial wire group had significant difference when compared to other groups regarding both the force magnitude and maximum deflection, the only exception was the debonding force of the flat braided retainer wires bonded to bovine teeth. In pull‐out test PEEK wires conditioned with adhesive system and the air‐abraded recorded the second and third highest readings respectively.ConclusionsWithin the limitations of this study, the 0.8 mm round PEEK wires have comparable performance—in terms of debonding and pull out forces—to conventional retainers when bonded with 4 mm composite bonding spots; using air‐abrasion for 10 s at 3.5 MPa provided sufficient adhesion of the composite to the wire, and conditioning with adhesive system may provide no further clinical benefit.
A prospective clinical evaluation of fixed dental prostheses made of metal alloys in patients with cerebral palsy
Authors: Magata Nobuaki , Tanoue Naomi , Ayuse Terumi , Ayuse Takao 
Published: December 2020

AbstractBackgroundIn general, the prevalence of caries and other oral and dental issues is increased in patients with disabilities, such as those with cerebral palsy. Providing appropriate dental treatment at a primary dental clinic for patients with cerebral palsy and intellectual disability, among other conditions, is challenging.ObjectiveThe objective of this study was to evaluate the longevity and investigate the related prognostic factors of fixed prostheses in patients with cerebral palsy.MethodsThe records of 36 cerebral palsy patients were used for collecting and analyzing data. A total of 155 prostheses made from metal alloys were finally included in this study. Annual failure rates were calculated; patient‐ and tooth‐related variables associated with prosthesis failure were assessed by a multivariate Cox‐regression analysis and frailty models to introduce random effects.ResultsThe 10‐year prosthesis survival rate was 62% and the 20‐year survival rate was 36%. In terms of prosthesis‐related variables, the type of prosthesis had a significant effect, and the hazard ratio of fixed partial dentures was 2.32 times that of single‐unit crowns. In terms of patient‐related variables, the presence of epilepsy had a significant effect on survival, and the hazard ratio for comorbid epilepsy was 3.76 times that for those without comorbid epilepsy.ConclusionsOur findings suggested that fixed prostheses placed in patients with cerebral palsy might have a particularly low survival rate in cases with comorbid epilepsy. It might also be important to consider the type and/or design of the prosthesis carefully to ensure a better prognosis.
Difference in stakeholder engagement approach of small & medium enterprises and large companies and its performance implications
Authors: Kumar Kamalesh , Batra Rishtee , Boesso Giacomo 
Published: December 2020

AbstractUsing the explicit and implicit Corporate Social Responsibility (CSR) framework, this study investigates how small and medium enterprises (SMEs) and large companies differ in their approach to CSR and what association these differing approaches to CSR have with a company's financial and social performances. We develop and validate a stakeholder engagement approach (SEA) scale and then present the results of data collected from 211 SMEs and 179 large companies. The results indicate that while large companies rely more on explicitly articulated and formally enacted approaches to CSR, SMEs integrate social responsibility into their company activities in informal and implicit ways. The results also show that the explicit approach has a positive association with financial performance measures, while the implicit approach has a positive association with social performance. The findings of this study provide a more nuanced and theoretically grounded understanding of differences in the CSR practices of SMEs and large companies.
Marein ameliorates AngII/hypoxia‐induced abnormal glucolipid metabolism by modulating theHIF‐1α/PPARα/γ pathway in H9c2 cells
Authors: Niu Guanghao , Zhou Mi , Wang Feng , Yang Jingxing , Huang Jie , Zhu Zengyan 
Published: December 2020

AbstractThe objectives of this study were to investigate the effects of marein, a major bioactive compound in functional foodCoreopsis tinctoria, in hypertrophic H9c2 cells. Treating angiotensin II/hypoxia‐stimulated H9c2 cells with marein led to decreasing cell surface area, intracellular total protein, atrial natriuretic peptide, and free fatty acids levels, but increasing glucose level. Marein treatment decreased hypoxia inducible factor‐1α (HIF‐1α), peroxisome proliferator activated receptor γ (PPARγ), medium chain acyl‐coenzyme A dehydrogenase, glucose transporter‐4, and glycerol‐3‐phosphate acyltransferase protein expressions, and increased PPARα, fatty acid transport protein‐1, carnitine palmitoyltransferase‐1, and pyruvate dehydrogenase kinase‐4 protein expressions. Similar results were observed in HIF‐1α‐overexpressing H9c2 cells, whereas these effects were abolished in siRNA‐HIF‐1α‐transfected H9c2 cells. It was concluded that marein could ameliorate abnormal glucolipid metabolism in hypertrophic H9c2 cells, and the effects could be attributable to reduction of HIF‐1α expression and subsequent regulation PPARα/γ‐mediated lipogenic gene expressions.
Estimated prevalence of eating disorders in Singapore
Authors: Chua Sook Ning , Fitzsimmons‐Craft Ellen E. , Austin S. Bryn , Wilfley Denise E. , Taylor C. Barr 
Published: December 2020

AbstractObjectiveThere is a lack of research on the prevalence of eating disorders (EDs) in Singapore. The aims of our study were to (a) estimate the prevalence of EDs, risk status, and help‐seeking behaviors among adults in Singapore, (b) examine gender differences between ED status groups, and (c) characterize clinical profiles of ED status groups.MethodWe administered a cross‐sectional survey that included a validated EDs screening tool to adults in Singapore.ResultsA total of 797 Singaporean adults ages 21–77 years completed the ED screen. The majority of participants screened positive for a current DSM‐5 clinical ED (6.2%), other specified feeding or ED (37.0%) or at high risk of developing an ED (19.5%). Only 1.6% of those who screened positive for an ED reported currently being in treatment. The ratio of males to females who screened positive for an ED was nearly 1:1. The clinical profiles of ED groups were consistent with the clinical presentations found in Western nations.DiscussionThis is the first study in Singapore to estimate the prevalence of EDs in a large sample of adults. Results highlight the urgent need for more ED research and expansion of prevention and treatment programs to address the high prevalence of ED psychopathology in Singapore.
Borohydride Reduction Method for PdIn/C Electrocatalysts Synthesis towards Glycerol Electrooxidation under Alkaline Condition
Authors: Nandenha Júlio , Ramos Carlos Eduardo Domingues , da Silva Sirlane G. , de Souza Rodrigo Fernando Brambilla , Fontes Eric Hossein , Ottoni Cristiane Angélica , Neto Almir Oliveira 
Published: December 2020

AbstractPd−In/C electrocatalysts were synthesized by the adapted borohydride reduction method in different atomic ratios. Electrocatalysts were evaluated by conventional electrochemical techniques and direct glycerol fuel cells. X‐ray diffraction profiles indicated the structure of Pd and In (fcc) phases, as well as the presence of In higher oxidation states. Regarding Transmission electron microscopy, it showed the particle‘s average diameters between 6.1–12.7 nm. All PdIn/C electrocatalysts showed high current values for −0.30 V vs. Ag/AgCl, which the best one was PdIn/C 90 : 10. Higher performance for glycerol oxidation was observed in polarization curves at 90 °C for PdIn/C (30 : 70) composition.
Global economic policy uncertainty and gold futures market volatility: Evidence from Markov regime‐switching GARCH‐MIDAS models
Authors: Ma Feng , Lu Xinjie , Wang Lu , Chevallier Julien 
Published: December 2020

AbstractThis paper explores the effects of global economic policy uncertainty (GEPU) on conditional volatility in the gold futures market using Markov regime‐switching GARCH‐MIDAS models. The in‐sample empirical results suggest that GEPU indeed contains predictive information for the gold futures market, and higher GEPU leads to higher volatility within the gold futures market. Moreover, the novel model, which adds Markov regime switching with time‐varying transition probabilities and the GEPU index, achieves relatively better performance than those of the other competing models from a statistical point of view. Furthermore, we discuss the asymmetric effects of different changes in GEPU on the gold futures market and the models' performances with different horizons, and we find that our new model has better predictive performance under negative changes in GEPU than under positive changes in GEPU. Further discussion also confirms that our previous findings are robust during two special cases, the global financial crisis and European debt crisis, during which the market suffered from fierce fluctuations and was fraught with considerable uncertainty.
Roles for H+/K+‐ATPase and zinc transporter 3 in cAMP‐mediated lysosomal acidification in bafilomycin A1‐treated astrocytes
Authors: Lee Huikyong , Koh Jae‐Young 
Published: December 2020

AbstractVacuolar ATPase (v‐ATPase) is the main proton pump that acidifies vesicles such as lysosomes. Disruption in the lysosomal localization of v‐ATPase leads to lysosomal dysfunction, thus contributing to the pathogenesis of lysosomal storage disorders and neurodegenerative diseases such as Alzheimer's disease. Recent studies showed that increases in cyclic AMP (cAMP) levels acidify lysosomes and consequently enhance autophagy flux. Although the upregulation of v‐ATPase function may be the key mechanism underlying the cAMP‐mediated lysosomal acidification, it is unknown whether a mechanism independent of v‐ATPase may be contributing to this phenomenon. In the present study, we modeled v‐ATPase dysfunction in brain cells by blocking lysosomal acidification in cortical astrocytes through treatment with bafilomycin A1, a selective v‐ATPase inhibitor. We observed that cAMP reversed the pH changes via the activation of protein kinase A; interestingly, cAMP also increased autophagy flux even in the presence of bafilomycin A1, suggesting the presence of an alternative route of proton entry. Notably, pharmacological inhibitors and siRNAs of H+/K+‐ATPase markedly shifted the lysosomal pH toward more alkaline values in bafilomycin A1/cAMP‐treated astrocytes, suggesting that H+/K+‐ATPase may be the alternative route of proton entry for lysosomal acidification. Furthermore, the cAMP‐mediated reversal of lysosomal pH was nullified in the absence of ZnT3 that interacts with H+/K+‐ATPase. Our results suggest that the H+/K+‐ATPase/ZnT3 complex is recruited to lysosomes in a cAMP‐dependent manner and functions as an alternative proton pump for lysosomes when the v‐ATPase function is downregulated, thus providing insight into the potential development of a new class of lysosome‐targeted therapeutics in neurodegenerative diseases.
Structural correlates underlying accelerated magnetic stimulation in Parkinson's disease
Authors: Ji Gong‐Jun , Liu Tingting , Li Ying , Liu Pingping , Sun Jinmei , Chen Xingui , Tian Yanghua , Chen Xianwen , Dahmani Louisa , Liu Hesheng , Wang Kai , Hu Panpan 
Published: December 2020

AbstractRepetitive transcranial magnetic stimulation (rTMS) is a noninvasive neuromodulation technique with great potential in the treatment of Parkinson's disease (PD). This study aimed to investigate the clinical efficacy of accelerated rTMS and to understand the underlying neural mechanism. In a double‐blinded way, a total of 42 patients with PD were randomized to receive real (n = 22) or sham (n = 20) continuous theta‐burst stimulation (cTBS) on the left supplementary motor area (SMA) for 14 consecutive days. Patients treated with real cTBS, but not with sham cTBS, showed a significant improvement in Part III of the Unified PD Rating Scale (p < .0001). This improvement was observed as early as 1 week after the start of cTBS treatment, and maintained 8 weeks after the end of the treatment. These findings indicated that the treatment response was swift with a long‐lasting effect. Imaging analyses showed that volume of the left globus pallidus (GP) increased after cTBS treatment. Furthermore, the volume change of GP was mildly correlated with symptom improvement and associated with the baseline fractional anisotropy of SMA‐GP tracts. Together, these findings implicated that the accelerated cTBS could effectively alleviate motor symptoms of PD, maybe by modulating the motor circuitry involving the SMA‐GP pathway.