Abstract:
:Linear porphyrin arrays self-assembled by either hydrogen bonding or metal ion coordination self-organize into lipid bilayer membranes. The length of the transmembrane assemblies is determined both by the thermodynamics of the intermolecular interactions in the supermolecule and by the dimension and physical chemical properties of the bilayer. Thus, the size of the porphyrin assembly can self-adjust to the thickness of the bilayer. An aqueous electron acceptor is placed on one side of the membrane and an electron donor is placed on the opposite side. When illuminated with white light, substantial photocurrents are observed. Only the assembled structures give rise to the photocurrent, as no current is observed from any of the component molecules. The fabrication of this photogated molecular electronic conductor from simple molecular components exploits several levels of self-assembly and self-organization.
journal_name
Proc Natl Acad Sci U S Aauthors
Drain CMdoi
10.1073/pnas.062635099keywords:
subject
Has Abstractpub_date
2002-04-16 00:00:00pages
5178-82issue
8eissn
0027-8424issn
1091-6490pii
062635099journal_volume
99pub_type
杂志文章abstract::NK cells are promising effectors for tumor adoptive immunotherapy, particularly when considering the targeting of MHC class I low or negative tumors. Yet, NK cells cannot respond to many tumors, which is particularly the case for nonhematopoietic tumors such as carcinomas or melanoma even when these cells lose MHC cla...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0804788105
更新日期:2008-11-11 00:00:00
abstract::Decision-making accuracy typically increases through collective integration of people's judgments into group decisions, a phenomenon known as the wisdom of crowds. For simple perceptual laboratory tasks, classic signal detection theory specifies the upper limit for collective integration benefits obtained by weighted ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1610732114
更新日期:2017-05-23 00:00:00
abstract::The clinical efficacy of local anesthetic and antiarrhythmic drugs is due to their voltage- and frequency-dependent block of Na+ channels. Quaternary local anesthetic analogs such as QX-314, which are permanently charged and membrane-impermeant, effectively block cardiac Na+ channels when applied from either side of t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.25.11839
更新日期:1995-12-05 00:00:00
abstract::Probing a wide range of cellular phenotypes in neurodevelopmental disorders using patient-derived neural progenitor cells (NPCs) can be facilitated by 3D assays, as 2D systems cannot entirely recapitulate the arrangement of cells in the brain. Here, we developed a previously unidentified 3D migration and differentiati...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1521255113
更新日期:2016-03-22 00:00:00
abstract::Glial fibrillary acidic protein (GFAP) is a member of the family of intermediate filament structural proteins and is found predominantly in astrocytes of the central nervous system (CNS). To assess the function of GFAP, we created GFAP-null mice using gene targeting in embryonic stem cells. The GFAP-null mice have nor...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.13.6361
更新日期:1996-06-25 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0706825105
更新日期:2008-03-25 00:00:00
abstract::We demonstrate theoretically and experimentally the spontaneous clustering of solitons in partially coherent wavefronts during the final stages of pattern formation initiated by modulation instability and noise. ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.072287299
更新日期:2002-04-16 00:00:00
abstract::Dentinal repair in the postnatal organism occurs through the activity of specialized cells, odontoblasts, that are thought to be maintained by an as yet undefined precursor population associated with pulp tissue. In this study, we isolated a clonogenic, rapidly proliferative population of cells from adult human dental...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.240309797
更新日期:2000-12-05 00:00:00
abstract::In nonneuronal cells, several plasma membrane proteins such as exofacial enzymes, receptors, and ion channels recycle between their intracellular compartment(s) and the cell surface via an endosomal pathway. In neurons, however, this pathway has not been extensively characterized. In particular, it remains unclear whe...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.1.183
更新日期:1998-01-06 00:00:00
abstract::To achieve the mission of personalized medicine, centering on delivering the right drug to the right patient at the right dose, therapeutic drug monitoring solutions are necessary. In that regard, wearable biosensing technologies, capable of tracking drug pharmacokinetics in noninvasively retrievable biofluids (e.g., ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.2009979117
更新日期:2020-08-11 00:00:00
abstract::Without sufficient greenhouse gases in the atmosphere, the early Earth would have become a permanently frozen planet because the young Sun was less luminous than it is today. Several resolutions to this faint young Sun-frozen Earth paradox have been proposed, with an atmosphere rich in CO2 being the one generally favo...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.91.4.1248
更新日期:1994-02-01 00:00:00
abstract::Exposure of Chinese hamster cells to reduced oxygen partial pressure results in a marked enhancement in the frequency of methotrexate resistance and dihydrofolate reductase gene amplification. The frequency of enhanced resistance is a function of the length of exposure to hypoxic conditions and the time after recovery...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.16.5978
更新日期:1986-08-01 00:00:00
abstract::The adenosine deaminases that act on RNA (ADARs) catalyze the site-specific conversion of adenosine to inosine (A to I) in primary mRNA transcripts, thereby affecting the splicing pattern or coding potential of mature mRNAs. Although the subnuclear localization of A-to-I editing has not been precisely defined, ADARs h...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.2336131100
更新日期:2003-11-25 00:00:00
abstract::DNA methylation at CpG dinucleotides is an important epigenetic regulator common to virtually all mammalian cell types, but recent evidence indicates that during early postnatal development neuronal genomes also accumulate uniquely high levels of two alternative forms of methylation, non-CpG methylation and hydroxymet...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.1411269112
更新日期:2015-06-02 00:00:00
abstract::As new disease threats arise and existing pathogens grow resistant to conventional interventions, attention increasingly focuses on the development of vaccines to induce protective immune responses. Given their admirable safety records, protein subunit vaccines are attractive for widespread immunization, but their dis...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0805532107
更新日期:2010-02-16 00:00:00
abstract::Landscape-scale reconstructions of ancient environments within the cradle of humanity may reveal insights into the relationship between early hominins and the changing resources around them. Many studies of Olduvai Gorge during Pliocene-Pleistocene times have revealed the presence of precession-driven wet-dry cycles a...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.2004532117
更新日期:2020-10-06 00:00:00
abstract::Several recombinant cowpox viruses were constructed and used to identify a viral gene that controls the production of hemorrhage in lesions caused by the Brighton Red strain of cowpox virus (CPV-BR). This gene is located in the KpnD fragment of CPV-BR DNA, between 31 and 32 kilobases from the end of the genome. This p...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.20.7698
更新日期:1986-10-01 00:00:00
abstract::Absorbance changes in untreated intact leaf discs, produced upon excitation with high-intensity red light, were shown to be due to the photooxidation of cytochrome b-559. At low intensities (<100 W/m2), photooxidation was almost undetectable. Photooxidation occurred with a half-time of 4.3 sec and an extent of 0.64 mo...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.23.9295
更新日期:1990-12-01 00:00:00
abstract::Na+ channels in chick brain and heart have been directly compared by measuring binding of tritium-labeled saxitoxin ([3H]STX) to the two tissues under identical conditions. Maximum saturable uptake and toxin affinity were considerably less in chick heart than in chick brain, requiring the development of an assay metho...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.4.1106
更新日期:1983-02-01 00:00:00
abstract::Two molecular forms of pyrophosphate-dependent phosphofructokinase (PP(i)-PFK; pyrophosphate:D-fructose-6-phosphate 1-phosphotransferase; EC 2.7.1.90) have been found whose activity depends upon association and dissociation characteristics regulated by fructose 2,6-bisphosphate (Fru-2,6-P(2)). PP(i)-PFK was purified 2...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.81.16.5051
更新日期:1984-08-01 00:00:00
abstract::The ever-increasing industrial demand for nylon-6 (polycaprolactam) necessitates the development of environmentally benign methods of producing its precursor, epsilon-caprolactam, from cyclohexanone. It is currently manufactured in two popular double-step processes, each of which uses highly aggressive reagents, and e...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0506907102
更新日期:2005-09-27 00:00:00
abstract::Using a novel technique of modulated photo-dissociation of carbon monoxide from hemoglobin, we have obtained the rates for conversion between the two quaternary states, R, and T, at 3-fold ligation. Our measurements at pH 7 and 22 degrees give rates of 780 +/- 40 sec-1 for going from R to T, and 2500 +/- 200 sec-1 fro...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.73.12.4497
更新日期:1976-12-01 00:00:00
abstract::Recent reports on the dystrophic mouse mutant suggest that the prominent extracellular matrix component of peripheral nerve tissues plays an important role in peripheral nerve development. We have examined the disposition of two prominent extracellular matrix components, fibronectin and laminin, both in mature periphe...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.12.3850
更新日期:1983-06-01 00:00:00
abstract::Three-dimensional topological insulators (3D TIs) represent states of quantum matters in which surface states are protected by time-reversal symmetry and an inversion occurs between bulk conduction and valence bands. However, the bulk-band inversion, which is intimately tied to the topologically nontrivial nature of 3...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1613110114
更新日期:2017-01-31 00:00:00
abstract::To understand the biogeochemical roles of microorganisms in the environment, it is important to determine when and under which conditions they are metabolically active. Bioorthogonal noncanonical amino acid tagging (BONCAT) can reveal active cells by tracking the incorporation of synthetic amino acids into newly synth...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1603757113
更新日期:2016-07-12 00:00:00
abstract::Mechanisms of bacterial pathogenesis have become an increasingly important subject as pathogens have become increasingly resistant to current antibiotics. The adhesion of microorganisms to the surface of host tissue is often a first step in pathogenesis and is a plausible target for new antiinfective agents. Examinati...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.230451697
更新日期:2000-11-21 00:00:00
abstract::A posttranslational protein O-mannosylation process resembling that found in fungi and animals has been reported in the major human pathogen Mycobacterium tuberculosis (Mtb) and related actinobacteria. However, the role and incidence of this process, which is essential in eukaryotes, have never been explored in Mtb. W...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1219704110
更新日期:2013-04-16 00:00:00
abstract::Inherited retinal degeneration (RD) is a devastating and currently untreatable neurodegenerative condition that leads to loss of photoreceptor cells and blindness. The vast genetic heterogeneity of RD, the lack of "druggable" targets, and the access-limiting blood-retinal barrier (BRB) present major hurdles toward eff...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1718792115
更新日期:2018-03-27 00:00:00
abstract::A 10-aa motif in transmembrane helix 1 of diphtheria toxin that is conserved in anthrax edema factor, anthrax lethal factor, and botulinum neurotoxin serotypes A, C, and D was identified by blast, clustal w, and meme computational analysis. Using the diphtheria toxin-related fusion protein toxin DAB(389)IL-2, we demon...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0504937102
更新日期:2005-10-25 00:00:00
abstract::DNase I hypersensitive regions were mapped within the 17.3-kilobase qa (quinic acid) gene cluster of Neurospora crassa. The 5'-flanking regions of the five qa structural genes and the two qa regulatory genes each contain DNase I hypersensitive sites under noninducing conditions and generally exhibit increases in DNase...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.17.6533
更新日期:1986-09-01 00:00:00