In this article, it is argued that while there has been an apparent eclipse in discourse regarding the publicness or public quality of public service, the recent transition toward a market-driven mode of governance has created a serious challenge to such publicness. More specifically, the contemporary businesslike changes in the objectives, structures, functions, norms, and users of public service tend to diminish its publicness in terms of its current trends toward eroding public-private distinction, shrinking socioeconomic role, narrowing composition of service recipients, worsening condition of accountability, and declining level of public trust. Based on the existing studies, empirical findings, and country experiences, this article delineates the basic criteria determining the publicness of public service, uses these criteria to demonstrate how the recent businesslike reforms have led to the erosion of such publicness, and makes recommendations for reviving the quality of publicness in public service.

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Uniform growth of pristine two dimensional (2D) materials over large areas at lower temperatures without sacrifice of their unique physical properties is a critical pre-requisite for seamless integration of next-generation van der Waals heterostructures into functional devices. This Letter describes a vapor phase growth technique for precisely controlled synthesis of continuous, uniform molecular layers of MoS2 on silicon dioxide and highly oriented pyrolitic graphite substrates of over several square centimeters at 350 °C. Synthesis of few-layer MoS2 in this ultra-high vacuum physical vapor deposition process yields materials with key optical and electronic properties identical to exfoliated layers. The films are composed of nano-scale domains with strong chemical binding between domain boundaries, allowing lift-off from the substrate and electronic transport measurements from contacts with separation on the order of centimeters.

We have added force and displacement measurement capabilities in the transmission electron microscope (TEM) for in situ quantitative tensile experimentation on nanoscale specimens. Employing the technique, we measured the stress-strain response of several nanoscale free-standing aluminum and gold films subjected to several loading and unloading cycles. We observed low elastic modulus, nonlinear elasticity, lack of work hardening, and macroscopically brittle nature in these metals when their average grain size is 50 nm or less. Direct in situ TEM observation of the absence of dislocations in these films even at high stresses points to a grain-boundary-based mechanism as a dominant contributing factor in nanoscale metal deformation. When grain size is larger, the same metals regain their macroscopic behavior. Addition of quantitative capability makes the TEM a versatile tool for new fundamental investigations on materials and structures at the nanoscale.N anomechanical behavior of materials has gained considerable attention because of the ever-shrinking dimensions of thin-film materials in microelectronics, data storage, and microelectromechanical sensors͞actuators, and also the advancements in bulk nanostructured materials. Mechanical properties of materials are influenced by their length-scales. For example, yield stress of polycrystalline metals increases with a decrease in grain size [Hall-Petch behavior (1, 2)], and strain-gradientdependent strengthening (3-6) occurs when the specimen size is reduced to the micrometer scale. Dislocations have been attributed to cause both of these behaviors as long as the grain size or the thickness is Ͼ100 nm. At smaller length-scales, straingradient-dependent strengthening disappears (7) and reverse Hall-Petch behavior is observed (8-13). Another less understood size effect observed at nanoscale is the reduction of Young's modulus, which has been attributed to specimen density (13) and grain boundary compliance (14,15). Models that attempt to explain the nanoscale size effect are of two basic types: (i) models describing nanocrystalline materials as twophase composites with grain interiors and boundaries, where the mechanical properties are averaged by simple ''rule of mixtures '' (16, 17); and (ii) models considering dislocation motion (10,18,19), grain boundary sliding (20, 21), and diffusion (12, 22) as competing deformation mechanisms. Although the literature has compelling evidence of these size-effects, the underlying deformation mechanisms are not yet well understood (23). Experimental MethodsDirect experimental observations of the deformation mechanisms mentioned above while the materials behavior is measured quantitatively is difficult at the nanoscale even with the recent novel existing approaches (24-28). We overcome the difficulty by developing microinstrumentation that combines quantitative tensile testing of thin films with the qualitative capabilities of the transmission electron microscope (TEM) so that one can simultaneously measure the stress-strain state...

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ABSTRACT--We present a new experimental method for the mechanical characterization of freestanding thin films with thickness on the order of nanometers to micrometers. The method allows, for the first time, in-situ SEM and TEM observation of materials response under uniaxial tension, with measurements of both stresses and strains under a wide variety of environmental conditions such as temperature and humidity.The materials that can be tested include metals, dielectrics, and multi-layer composites that can be deposited/grown on a silicon substrate. The method involves lithography and bulk micromachining techniques to pattern the specimen of desired geometry, release the specimen from the substrate, and co-fabricate a force sensor with the specimen. Co-fabrication provides perfect alignment and gripping. The tensile testing fits an existing TEM straining stage, and a SEM stage. We demonstrate the proposed methodology by fabricating a 200 nm thick, 23.5 I~m wide, and 185 I~m long freestanding sputter deposited aluminum specimen. The testing was done in-situ inside an environmental SEM chamber. The stressstrain diagram of the specimen shows a linear elastic regime up to the yield stress cry = 330 MPa, with an elastic modulus E = 74.6 GPa.

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