Recent advances in submolecular resolution with scanning probe microscopy.

Recently scanning probe microscopy has made tremendous progress in imaging organic molecules with high lateral resolution. Atoms and bonds within individual molecules have been clearly resolved, indicating the exciting potential of this technique for studying molecular structures, bonding within and between molecules, molecular conformational changes and chemical reactions at the single-molecule level. It turns out that the key step enabling such studies is an atomically controlled functionalization of the microscope tip. In this Perspective, the different techniques used for high-resolution molecular imaging, their implementations, advantages and limitations are described, and possible scientific areas of applications are discussed.

Understanding the concept of randomness in inelastic electron tunneling excitations.

Inelastic electron tunneling excitation has been realized in the last decade as an effective way to probe reliably detailed atomic structures and control precisely behaviors of surface adsorbates at a single molecule level. A good understanding of rich and complex processes on the surface under inelastic electron excitations is of great importance, not only from a fundamental scientific point of view but also for potential practical applications. In this perspective paper, we give an overview of recent developments on excitations and characterizations of inelastic electron tunneling processes in surface adsorbates and molecular junctions. Special attention has been paid to the understanding of the randomness of the processes. A recently proposed general statistical model is introduced which has resolved a long-standing puzzle concerning the experimentally observed non-integer power law relationship between the rate of molecular conformation changes and the tunneling current. The success of the new model is highlighted by its applications for molecular switches.

Scanning tunneling spectroscopy.

The scanning tunneling microscope (STM) has revolutionized our ability to explore and manipulate atomic-scale solid surfaces. In addition to its unparalleled spatial power, the STM can study dynamical processes, such as molecular conformational changes, by recording current traces as a function of time. It can also be employed to measure the physical properties of molecules or nanostructures down to the atomic scale. Combining STM imaging with measurement of current-voltage (I-V) characteristics [i.e., scanning tunneling spectroscopy (STS)] at similar resolution makes it possible to obtain a detailed map of the electronic structure of a surface. For many years, STM lacked chemical specificity; however, the recent development of STM-IETS (inelastic electron tunneling spectroscopy) has allowed us to measure the vibrational spectrum of a single molecule. This review introduces and illustrates these recent developments with a few simple scholarly examples.

The evolution and future of minimalism in neurological surgery.

INTRODUCTION: The evolution of the field of neurological surgery has been marked by a progressive minimalism. This has been evident in the development of an entire arsenal of modern neurosurgical enterprises, including microneurosurgery, neuroendoscopy, stereotactic neurosurgery, endovascular techniques, radiosurgical systems, intraoperative and navigational devices, and in the last decade, cellular and molecular adjuvants. AIMS: In addition to reviewing the major developments and paradigm shifts in the cyclic reinvention of the field as it currently stands, this paper attempts to identify forces and developments that are likely to fuel the irresistible escalation of minimalism into the future. These forces include discoveries in computational science, imaging, molecular science, biomedical engineering, and information processing as they relate to the theme of minimalism. DISCUSSION: These areas are explained in the light of future possibilities offered by the emerging field of nanotechnology with molecular engineering.

[Scanning probe microscopy and medico-biological nanotechnology: history and prospects]. / Skaniruiushchaia zondovaia mikroskopiia i mediko-biologicheskaia nanotekhnologiia: istoriia i perspektivy.

Literature data on the use of scanning probe microscopy for biological samples studying are presented. As an illustration, some results of the authors' investigations of the shark olfactory receptor surface, human lipoprotein of low density and human erythrocyte are given. Perspectives of the medico-biological development of nanotechnologies are evaluated.

Application of scanning tunneling microscopy to structural biology.

Scanning tunneling microscopy offers the possibility of visualizing biological molecules in conditions similar to those in vivo with molecular resolution. Images of DNA and various proteins have been obtained, but insufficient conductivity through, and inhomogeneous and unstable adsorption of the biomolecules continue to prevent reliable imaging. Applying a metal coating to samples, to separate the conductivity and deposition problems has yielded satisfactory deposition procedures in various laboratories, but extension of this protocol to high resolution imaging of macromolecules has yet to be demonstrated. In this paper we present a review of the main results obtained in our laboratory, which illustrate the main problems encountered by investigators attempting to image metal-coated and uncoated biological specimens.