Now showing items 3076-3095 of 14548

• #### Direct measurement of the Zak phase in topological Bloch bands ﻿

(Nature Publishing Group, 2013)
Geometric phases that characterize the topological properties of Bloch bands play a fundamental role in the band theory of solids. Here we report on the measurement of the geometric phase acquired by cold atoms moving in ...
• #### Direct Observation of a Long-Lived Single-Atom Catalyst Chiseling Atomic Structures in Graphene ﻿

(American Chemical Society (ACS), 2014)
Fabricating stable functional devices at the atomic scale is an ultimate goal of nanotechnology. In biological processes, such high-precision operations are accomplished by enzymes. A counterpart molecular catalyst that ...
• #### Direct Observation of a Sharp Transition to Coherence in Dense Cores ﻿

(American Astronomical Society, 2010)
We present $NH_3$ observations of the B5 region in Perseus obtained with the Green Bank Telescope. The map covers a region large enough $(\sim 11'×14')$ that it contains the entire dense core observed in previous dust ...
• #### Direct parsing of ID/LP grammars ﻿

(Springer, 1984)
The Immediate Dominance/Linear Precedence (ID/LP) formalism is a recent extension of Generalized Phrase Structure Grammar (GPSG) designed to perform some of the tasks previously assigned to metarules--for example, modeling ...
• #### Direct phase-sensitive identification of a d-form factor density wave in underdoped cuprates ﻿

(Proceedings of the National Academy of Sciences, 2014)
The identity of the fundamental broken symmetry (if any) in the underdoped cuprates is unresolved. However, evidence has been accumulating that this state may be an unconventional density wave. Here we carry out site-specific ...
• #### Direct Photon Production With Eﬀective Field Theory ﻿

(Springer Verlag, 2010)
The production of hard photons in hadronic collisions is studied using Soft-Collinear Effective Theory (SCET). This is the first application of SCET to a physical, observable cross section involving energetic partons in ...
• #### Direct Realism and Perceptual Consciousness. ﻿

(Wiley-Blackwell, 2006)
• #### Direct Reciprocity on Graphs ﻿

(Elsevier, 2007)
Direct reciprocity is a mechanism for the evolution of cooperation based on the idea of repeated encounters between the same two individuals. Here we examine direct reciprocity in structured populations, where individuals ...
• #### Direct Reciprocity with Costly Punishment: Generous Tit-for-Tat Prevails ﻿

(Elsevier, 2009)
The standard model for direct reciprocity is the repeated Prisoner's Dilemma, where in each round players choose between cooperation and defection. Here we extend the standard framework to include costly punishment. Now ...
• #### Direct recognition of homology between double helices of DNA in Neurospora crassa ﻿

(2014)
Chromosomal regions of identical or nearly identical DNA sequence can preferentially associate with one another in the apparent absence of DNA breakage. Molecular mechanism(s) underlying such homology-dependent pairing ...
• #### Direct recording and molecular identification of the calcium channel of primary cilia ﻿

(2014)
Summary A primary cilium is a solitary slender non-motile protuberance of structured microtubules (9+0) enclosed by plasma membrane1. Housing components of the cell division apparatus between cell divisions, they also serve ...
• #### Direct Recruitment of Polycomb Repressive Complex 1 to Chromatin by Core Binding Transcription Factors ﻿

(Elsevier BV, 2012)
Polycomb repressive complexes (PRCs) play key roles in developmental epigenetic regulation. Yet the mechanisms that target PRCs to specific loci in mammalian cells remain incompletely understood. In this study we show that ...
• #### Direct Structural Observation of a Molecular Junction by High-Energy X-Ray Reflectometry ﻿

We report a direct angstrom resolution measurement of the structure of a molecular-size electronic junction comprising a single (or a double) layer of alkyl-thiol and alkyl-silane molecules at the buried interface between ...
• #### Direct Suppression as a Mechanism for Controlling Unpleasant Memories in Daily Life ﻿

(American Psychological Association, 2014)
Suppressing unwanted memories can impair their later recall. Recent work shows that this forgetting is achieved by at least two mechanisms supported by distinct neural systems: thought substitution and direct suppression ...
• #### Direct Transformation of 2,3-Epoxy Alcohols into Hydroxy Carbonates Under Mildly Basic Conditions ﻿

(Elsevier, 1988)
2,3-Epoxy alcohols are transformed into the corresponding C2-inverted hydroxy carbonates upon treatment with cesium carbonate-powdered 3-A molecular sieves in N,N-dimethylformamide under one atmosphere of carbon dioxide ...
• #### Direct Versus Indirect Remedies for Externalities ﻿

(University of Chicago Press, 1976)
This paper is concerned with tax policies designed to obtain an improved competitive allocation in the presence of consumption externalities. It is known that the full optimum can, in general, be attained only through the ...
• #### Direct visualization of quasi-ordered oxygen chain structures on Au(110)-(1×2) ﻿

(Elsevier BV, 2016)
The Au(110) surface offers unique advantages for atomically-resolved model studies of catalytic oxidation processes on gold. We investigate the adsorption of oxygen on Au(110) using a combination of scanning tunneling ...
• #### Direct Writing and Actuation of Three-Dimensionally Patterned Hydrogel Pads on Micropillar Supports ﻿

(Wiley-Blackwell, 2011)
Freely swelling, three-dimensionally patterned responsive hydrogels fabricated by multiphoton lithography on the tips of flexible pillars provide unique capabilities for the design of adaptive systems. The resulting materials ...
• #### Direct-Liquid-Evaporation Chemical Vapor Deposition of Nanocrystalline Cobalt Metal for Nanoscale Copper Interconnect Encapsulation ﻿

(American Chemical Society (ACS), 2017)
In advanced microelectronics, precise design of liner and capping layers become critical, especially when it comes to the fabrication of Cu interconnects with dimensions lower than its mean free path. Herein, we demonstrate ...
• #### Direct-liquid-evaporation chemical vapor deposition of smooth, highly conformal cobalt and cobalt nitride thin films ﻿

(Royal Society of Chemistry (RSC), 2015)