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Institution

Boston College

EducationBoston, Massachusetts, United States
About: Boston College is a education organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 9749 authors who have published 25406 publications receiving 1105145 citations. The organization is also known as: BC.


Papers
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Journal ArticleDOI
TL;DR: It is shown that Immerman's families of circuits defined by first-order formulas and a uniformity corresponding to Buss' deterministic log-time reductions are equivalent, leading to a natural notion of uniformity for low-level circuit complexity classes.

536 citations

Journal ArticleDOI
Arch G. Woodside1
TL;DR: In this paper, the authors describe the tenets of complexity theory including the precept that within the same set of data X relates to Y positively, negatively, and not at all, and show that reporting how X relates positively to Y with and without additional terms in multiple regression models ignores important information available in a data set.

535 citations

Journal ArticleDOI
TL;DR: In this article, the authors pointed out that African universities currently function in very difficult circumstances, both in terms ofthe social, economic, and political problemsfacing the continent and in the context ofglobalization, and the road to future success will not be an easy one.
Abstract: African higher education, atthe beginning of the new millennium, facesunprecedented challenges. Not only is thedemand for access unstoppable, especially inthe context of Africa's traditionally lowpostsecondary attendance levels, but highereducation is recognized as a key force formodernization and development. Africa'sacademic institutions face obstacles inproviding the education, research, and serviceneeded if the continent is to advance.Generalizing about a continent as large anddiverse as Africa is difficult. Yet there aresome common elements – and there are certainlysome common challenges. In our discussion, weare not generally optimistic either inanalyzing the current reality in much of Africaor in pointing to future prospects. The fact isthat African universities currently function invery difficult circumstances, both in terms ofthe social, economic, and political problemsfacing the continent and in the context ofglobalization, and the road to future successwill not be an easy one.

534 citations

Journal ArticleDOI
TL;DR: A highly efficient molecular delivery technique, named nanotube spearing, based on the penetration of nickel-embedded nanotubes into cell membranes by magnetic field driving is reported, achieving an unprecedented high transduction efficiency in Bal17 B-lymphoma, ex vivo B cells and primary neurons with high viability after transduction.
Abstract: Introduction of exogenous DNA into mammalian cells represents a powerful approach for manipulating signal transduction. The available techniques, however, are limited by low transduction efficiency and low cell viability after transduction. Here we report a highly efficient molecular delivery technique, named nanotube spearing, based on the penetration of nickel-embedded nanotubes into cell membranes by magnetic field driving. DNA plasmids containing the enhanced green fluorescent protein (EGFP) sequence were immobilized onto the nanotubes, and subsequently speared into targeted cells. We have achieved an unprecedented high transduction efficiency in Bal17 B-lymphoma, ex vivo B cells and primary neurons with high viability after transduction. This technique may provide a powerful tool for highly efficient gene transfer into a variety of cells, especially the hard-to-transfect cells.

534 citations

Journal ArticleDOI
TL;DR: A hybrid density functional theory has been utilized to put forward a triangular Mn moiety closely coupled by μ-oxo groups as a potential model for the WO site and another mechanism incorporating a “C-shaped” cluster has also been suggested recently.
Abstract: ion model is not a true H-abstracting process but rather a special case of proton-coupled electron transfer where reduction of YZ by the Mn4 cluster occurs with the proton emanating from solvent water. These two theories will now be described briefly. A hydrogen atom abstraction process by the YZ residue in conjunction with a dimer-of-dimers structural template has led to an interesting hypothesis wherein an O atom is proposed as a terminal ligand to Mn (see Figure 8 (top)).175,188 The Clion is proposed to migrate in S1 to S2 and S2 to S3 state transitions while YZ serves as the H atom abstractor and Ca2+ ion binds to Clin the lower S states. In another proposal two dinuclear Mn complexes perform diverse functions: one oxidizes H2O to peroxide while the other converts peroxide to water.16,189-191 The final O-O bond forming step in the S4 state is predicted to result from attack of the hydroxo group bound to Ca2+ to a strongly electrophilic MnVdO species. In a similar hypothesis, a Clbridging between a Mn and a Ca2+ is responsible for modulating the nucleophilic attack of the hydroxide ion.181,192 This was first predicted from mass spectrometric studies.176 The product of this step has been argued to be similar to the ferric hydroperoxide in oxyhemerythrin. Oxygen release is envisioned in a manner similar to that of oxyhemerythrin concomitant with reduction of Mn and protonation of μ-oxo bridges.192 On the basis of XAS and EPR data, another mechanism incorporating a “C-shaped” cluster has also been suggested recently involving one redox-active Mn per [Mn2(μ-O)2] dimeric moiety (see Figure 8 (bottom)).17,193,194 Here, the O-O bond is formed between an oxyl radical and a μ-oxo atom. A hybrid density functional theory has been utilized to put forward a triangular Mn moiety closely coupled by μ-oxo groups as a potential model for the WO site. The previously suggested oxyl radical mechanism14 has been reexamined in this work with an oxyl radical placed in a bridging fashion between two Mn atoms. Consistent with earlier studies, only one Mn is redox active in this model and the Ca2+ ion has been shown as playing the role of a bridging metal Manganese Clusters with Relevance to Photosystem II Chemical Reviews, 2004, Vol. 104, No. 9 3991

533 citations


Authors

Showing all 9922 results

NameH-indexPapersCitations
Eric J. Topol1931373151025
Gang Chen1673372149819
Wei Li1581855124748
Daniel L. Schacter14959290148
Asli Demirguc-Kunt13742978166
Stephen G. Ellis12765565073
James A. Russell124102487929
Zhifeng Ren12269571212
Jeffrey J. Popma12170272455
Mike Clarke1131037164328
Kendall N. Houk11299754877
James M. Poterba10748744868
Gregory C. Fu10638132248
Myles Brown10534852423
Richard R. Schrock10372443919
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
202398
2022250
20211,282
20201,275
20191,082
20181,058