Job management is a key issue in computational grids, and normally involves job definition, scheduling, executing and monitoring. However, job management in the existing grid middleware needs to be ...improved in terms of efficiency and flexibility. This paper addresses a flexible architecture for job management with detailed design and implementation. Frameworks for job scheduling and monitoring, as two important aspects, are also presented. The proposed job management has the advantages of reusability of job definition, flexible and automatic file operation, visual steering of file transfer and job execution, and adaptive application job scheduler. A job management wizard is designed to implement each step. Therefore, what the grid user needs to do is only to define the job by constructing necessary information at runtime. In addition, the job space is adopted to ensure the security of the job management. Experimental results showed that this approach is user-friendly and system efficient.
Yttria-stabilized-zirconia （YSZ） hollow spheres are widely utilized for their novel physical and chemical properties. However, developing a simple and low-cost method for preparing such hollow ...spheres still remains a great challenge. In this paper, an atmospheric plasma spray （APS） method is introduced, and the formation mechanism of hollow 7YSZ （ZrO2-7wt%Y2O3） spheres is presented. The hollow sphere morphology was observed by scanning electron microscopy （SEM） when agglomerated and sintered 7YSZ powders were used. Additionally, additive composition changes, phase transformations, and the thermal behavior of 7YSZ powders were analyzed by energy dispersive spectroscopy （EDS）, X-ray diffractometry （XRD）, thermogravimetric analysis （TG） and differential scanning calorimeter analysis （DSC）. Furthermore, the phase transformations of agglomerated and sintered 7YSZ powders, 7YSZ hollow spheres that annealed at various temperatures for different times are analyzed.
Herein we described an efficient RhII‐catalyzed enantioselective cyclopropenation reaction of internal alkynes with a masked difluorodiazoethane reagent (PhSO2CF2CHN2, Ps‐DFA). This asymmetric ...transformation offers efficient access to a broad range of enantioenriched difluoromethylated cyclopropenes (40 examples, up to 99 % yield, 97 % ee). The synthetic utility of obtained strained carbocycles is demonstrated by subsequent stereodefined processes, including cross‐couplings, hydrogenation, Diels–Alder reaction, and Pauson–Khand reaction.
Three's a crowd: A highly enantioselective RhII‐catalyzed cyclopropenation reaction of difluorodiazoethane (PhSO2CF2CHN2) with challenging internal alkynes is reported (up to 99 % yield, 97 % ee). Versatile stereoselective transformations of these unique strained cyclopropenes are also demonstrated.
Remote functionalization reactions have the power to transform a C−H (or C−C) bond at a distant position from a functional group. This Review summarizes recent advances and key breakthroughs in ...remote fluorination, trifluoromethylation, difluoromethylation, trifluoromethylthiolation, and fluoroalkenylation reactions. Several powerful strategies have emerged to control the reactivity and distal selectivity such as the undirected radical approach, the 1,5‐hydrogen atom transfer, the metal migration, the use of distant directing groups, and the ring‐opening reactions. These unconventional and predictable C−H (and C−C) functionalization transformations should allow for the preparation of a wide range of otherwise‐difficult‐to‐access alkyl, aromatic, heteroaromatic, and structurally complex fluorides.
Heading to a remote reaction pattern for fluorine: Remote fluorination and fluoroalkyl(thiol)ation reactions transform C−H and C−C bonds far from a functional group has received increasing attention in the past decade. This Review summarizes recent advances and key breakthroughs in remote fluorination, trifluoromethylation, difluoromethylation, trifluoromethylthiolation, and fluoroalkenylation reactions of alkyl/aromatic C−H and C−C bonds.
The application of abundant and inexpensive fluorine feedstock sources to synthesize fluorinated compounds is an appealing yet underexplored strategy. Here, we report a photocatalytic radical ...hydrodifluoromethylation of unactivated alkenes with an inexpensive industrial chemical, chlorodifluoromethane (ClCF2H, Freon-22). This protocol is realized by merging tertiary amine-ligated boryl radical-induced halogen atom transfer (XAT) with organophotoredox catalysis under blue light irradiation. A broad scope of readily accessible alkenes featuring a variety of functional groups and drug and natural product moieties could be selectively difluoromethylated with good efficiency in a metal-free manner. Combined experimental and computational studies suggest that the key XAT process of ClCF2H is both thermodynamically and kinetically favored over the hydrogen atom transfer pathway owing to the formation of a strong boron–chlorine (B–Cl) bond and the low-lying antibonding orbital of the carbon–chlorine (C–Cl) bond.
Abstract The dynamics of proteins are crucial for understanding their mechanisms. However, computationally predicting protein dynamic information has proven challenging. Here, we propose a neural ...network model, RMSF-net, which outperforms previous methods and produces the best results in a large-scale protein dynamics dataset; this model can accurately infer the dynamic information of a protein in only a few seconds. By learning effectively from experimental protein structure data and cryo-electron microscopy (cryo-EM) data integration, our approach is able to accurately identify the interactive bidirectional constraints and supervision between cryo-EM maps and PDB models in maximizing the dynamic prediction efficacy. Rigorous 5-fold cross-validation on the dataset demonstrates that RMSF-net achieves test correlation coefficients of 0.746 ± 0.127 at the voxel level and 0.765 ± 0.109 at the residue level, showcasing its ability to deliver dynamic predictions closely approximating molecular dynamics simulations. Additionally, it offers real-time dynamic inference with minimal storage overhead on the order of megabytes. RMSF-net is a freely accessible tool and is anticipated to play an essential role in the study of protein dynamics.
Click-Through Rate (CTR) prediction is one of the most challenging tasks in the advertising systems, which aims to estimate the probability of a candidate user clicking on a candidate item. Recently, ...CTR prediction has observed remarkable progress, due to the advances of the Deep Neural network (DNN) in learning representation. However, most of the existing DNN-based methods focus on modeling implicit information from the user aspect, while ignoring the correlations between the user and other objects in the historical interactive behaviors (e.g., user→items or user→users). Additionally, the large-scale historical interactive behaviors also bring the model a lot of difficulty in finding precise relations from redundant and noisy data. Targeted at the above issues, our paper introduces a simple yet effective model, which boosts the user-view and item-view (i.e., dual-view) to extract various interactive relationships for CTR prediction. Therefore, we name our model as Dual-View Attention Network (DVAN). More specifically, we propose a cross-domain attention module (i.e., user→items and item→users) to extract the coarse-level correlations, and a local homogeneous-domain attention module (i.e., user→users and item→items) to extract the fine-level correlations adaptively. In order to extract the accurate relationship from the large-scale historical behaviors, a novel selection mechanism is introduced to connect the cross-domain attention module and the local homogeneous-domain attention module, and thus builds representation from the coarse-level to the fine-level gradually. Experimental results on four public datasets have demonstrated the effectiveness of our method, which outperforms existing state-of-the-art methods.
•Extracting features from different views can add effective prior information.•Attention is used based on the user’s differential preferences and the item’s similarities.•Using sigmoid to model the relation can accommodate the problem of a large number of inputs.•Remove noisy behaviors to refine behavior list with the help of attention scores.
The development of new synthetic strategies for the efficient construction of versatile pyrrole pharmacores, especially in an operationally simple and environmentally benign fashion, still remains a ...momentous yet challenging goal. Here, we report a KOAc-catalyzed double decarboxylative transannulation between readily accessible oxazolones and isoxazolidinediones. This transformation represents a new way for skeletal remodeling by utilizing CO2 moiety as traceless activating and directing groups in both reaction partners. The synthetic value is evidenced by the rapid preparation of a broad spectrum of highly functionalized 3-carbamoyl-4-aryl pyrroles in good to excellent yields with exclusive regio-control, including the important Atorvastatin core.
We report a general and efficient approach to construct achiral and chiral gem-difluoroallylic amines from a masked difluorodiazo reagent (PhSO2CF2CHN2) and readily available imines. This facile ...protocol takes advantage of the phenylsulfonyl and diazo moieties as efficient activating and directing groups to assist difluoroalkyl incorporation and facilitate the chemodivergent and stereoselective formation of gem-difluoroallylic amines.
