662 research outputs found
A Novel and General Method for the Formation of S-Aryl, Se-Aryl, and Te-Aryl Phosphorochalcogenoates
A new and general method for the synthesis of S-, Se-, and Te-aryl phosphorochalcogenoates (chalcogenophosphates) has been developed. S-P, Se-P, and Te-P bonds were formed by the coupling of readily available dialkyl phosphites with diaryl dichalcogenides at 30 degrees C in dimethyl sulfoxide in the presence of catalytic amounts of copper iodide and diethylamine. The reaction proceeded smoothly without exclusion of moisture or air.Major Program of National Natural Science Foundation of China [20732004, J0630429]; Projects of International Cooperation of the Ministry of Science and Technology of the Peoples Republic of China [2006DFA43030
Power allocation for cache-aided small-cell networks with limited backhaul
Cache-aided small-cell network is becoming an effective method to improve the transmission rate and reduce the backhaul load. Due to the limited capacity of backhaul, less power should be allocated to users whose requested contents do not exist in the local caches to maximize the performance of caching. In this paper, power allocation is considered to improve the performance of cache-aided small-cell networks with limited backhaul, where interference alignment (IA) is utilized to manage interferences among users. Specifically, three power allocation algorithms are proposed. First, we come up with a power allocation algorithm to maximize the sum transmission rate of the network, considering the limitation of backhaul. Second, in order to have more users meet their rate requirements, a power allocation algorithm to minimizing the average outage probability is also proposed. In addition, in order to further improve the users’ experience, a power allocation algorithm that maximizes the average satisfaction of all the users is also designed. Simulation results are provided to show the effectiveness of the three proposed power allocation algorithms for cache-aided small-cell networks with limited backhaul
BCL9 enhances the development of cervical carcinoma by deactivating CPEB3/EGFR axis
Purpose: To investigate the differential expression of BCL9 in cervical carcinoma samples, analyze its biological functions in regulating malignant phenotypes of cervical carcinoma cells, and to explore its potential molecular mechanism.Methods: Expression levels of BCL9 in 58 pairs of cervical carcinoma tissues and paracancerous tissues were determined using quantitative real time-polymerase chain reaction (qRT-PCR). Kaplan- Meier curves were used to analyze the prognostic potential of BCL9 in cervical carcinoma. After knockdown using BCL9 by lentivirus transfection, proliferative and migratory changes in Siha and HeLa cells were determined by CCK-8, colony formation and Transwell assays. Cytoplasmic polyadenylation element binding protein 3 (CPEB3), the potential downstream target of BCL9, was confirmed via dualluciferase reporter assay. Western blot analyses were conducted to determine the protein levels of CPEB3, EGFR, AKT and p21 in Siha and HeLa cells with BCL9 knockdown. The co-regulation of BCL9 and CPEB3 on phenotypes of cervical carcinoma cell was investigated.Results: BCL9 was upregulated in cervical carcinoma tissues. The high level of BCL9 was predicted by the tumor size, advanced stage and poor prognosis. The knockdown of BCL9 significantly weakened proliferative and migratory abilities of Siha and HeLa cells (p < 0.05). CPEB3 was the downstream target of BCL9, and was lowly expressed in cervical carcinoma tissues. The knockdown of BCL9 upregulated CPEB3, and downregulated EGFR, AKT and p21 (p < 0.05). The knockdown of CPEB3 also reversed the influence of silenced BCL9 in regulating its proliferative and migratory abilities in cervical carcinoma cells (p < 0.05).Conclusion: BCL9 drives the deterioration of cervical carcinoma by inhibiting the CPEB3/EGFR axis.Thus, BCL9 may be a novel molecular target for cervical carcinoma treatment
(S)-Benzyl 2-amino-3-(4-hydroxyphenyl)propanoate
The title compound, C16H17NO3, adopts a folded conformation in the crystal structure. The crystal packing is stabilized by intermolecular O—H⋯O and N—H⋯O hydrogen-bonding interactions. The absolute configuration was assigned assuming that the absolute configuration of the starting material l-tyrosine was retained during the synthesis
Benzyl 2,5-dioxopyrrolidin-1-yl carbonate
The asymmetric unit of the title compound, C12H11NO5, contains two independent molecules with similar geometric parameters but different orientations of the phenyl rings. The molecular packing is stabilized by weak nonclassical C—H⋯O hydrogen-bonding interactions
N-(4-Chlorophenyl)-2-deoxy-α-l-ribopyranosylamine
In the crystal structure of the title compound, C11H14ClNO3, intermolecular hydrogen bonds link molecules in the ab plane, forming layers that stack along the c axis
Novel N,S-phenacyl protecting group and its application for peptide synthesis
The phenacyl group can be introduced onto amino and thio groups by N,S-alkylation reactions. Conversely, these groups are removed rapidly by employing magnesium in acetic acid. This protecting group was successfully applied to a short peptide synthesis of Boc-L-Cys-Gly-OMe
N-Benzyl-2-propynamide
Pale-yellow crystals of the title compound, C10H9NO, have been obtained by the reaction of benzylamine and methyl propiolate. Weak intermolecular hydrogen bonding is observed between acetylenic H and carbonyl O atoms. The crystal packing is stabilized by these C—H⋯O and by N—H⋯O intermolecular hydrogen-bonding interactions
Benzoylmethyl 4-chlorobenzoate
The asymmetric unit of the title compound, C15H11ClO3, contains three molecules, A, B, and C. Molecules A and B are aligned edge-to-face, whereas molecules B and C are aligned almost parallel to each other. The crystal structure displays C—H⋯π and π–π [centroid–centroid distances of 3.960 (4), 3.971 (4) and 3.971 (4) for molecules A, B and C, respectively] parallel-displaced interactions, and C—H⋯O hydrogen bonds
Strain Induced One-Dimensional Landau-Level Quantization in Corrugated Graphene
Theoretical research has predicted that ripples of graphene generates
effective gauge field on its low energy electronic structure and could lead to
zero-energy flat bands, which are the analog of Landau levels in real magnetic
fields. Here we demonstrate, using a combination of scanning tunneling
microscopy and tight-binding approximation, that the zero-energy Landau levels
with vanishing Fermi velocities will form when the effective pseudomagnetic
flux per ripple is larger than the flux quantum. Our analysis indicates that
the effective gauge field of the ripples results in zero-energy flat bands in
one direction but not in another. The Fermi velocities in the perpendicular
direction of the ripples are not renormalized at all. The condition to generate
the ripples is also discussed according to classical thin-film elasticity
theory.Comment: 4 figures, Phys. Rev.
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