Tissue culture plastic adhesivity was precisely varied by applying different concentrations of poly(2-hydroxyethyl methacrylate). The extent of cell spreading was thus accurately controlled so that cells cultured on these substrata could be held at any one of a graded series of quantitated cell shapes. Cell shape was found to be tightly coupled to DNA synthesis and growth in nontransformed cells. These findings suggest a mechanism that is important in growth control of mammalian cells, and provide a more fundamental interpretation of such phenomena as density dependent inhibition of cell growth and anchorage dependence.

Role of cell shape in growth control

▪ Abstract Semiconductor nanowires and nanotubes exhibit novel electronic and optical properties owing to their unique structural one-dimensionality and possible quantum confinement effects in two dimensions. With a broad selection of compositions and band structures, these one-dimensional semiconductor nanostructures are considered to be the critical components in a wide range of potential nanoscale device applications. To fully exploit these one-dimensional nanostructures, current research has focused on rational synthetic control of one-dimensional nanoscale building blocks, novel properties characterization and device fabrication based on nanowire building blocks, and integration of nanowire elements into complex functional architectures. Significant progress has been made in a few short years. This review highlights the recent advances in the field, using work from this laboratory for illustration. The understanding of general nanocrystal growth mechanisms serves as the foundation for the rational sy...

/pdf/semiconductor-nanowires-and-nanotubes-27j4coa812.pdf

Semiconductor nanowires and nanotubes

Calmodulin, a protein that binds calcium with high affinity and specificity, is structurally conserved and functionally preserved throughout the animal and plant kingdoms. It serves as an intracellular Ca2+-receptor and mediates the Ca2+ regulation of cyclic nucleotide and glycogen metabolism, secretion, motility and Ca2+ transport. Calmodulin is also a dynamic component of the mitotic apparatus.

Calmodulin—an intracellular calcium receptor

Vegetation provides a major source of reactive carbon entering the atmosphere. These compounds play an important role in (1) shaping global tropospheric chemistry, (2) regional photochemical oxidant formation, (3) balancing the global carbon cycle, and (4) production of organic acids which contribute to acidic deposition in rural areas. Present estimates place the total annual global emission of these compounds between approximately 500 and 825 Tg yr−1. The volatile olefinic compounds, such as isoprene and the monoterpenes, are thought to constitute the bulk of these emissions. However, it is becoming increasingly clear that a variety of partially oxidized hydrocarbons, principally alcohols, are also emitted. The available information concerning the terrestrial vegetation as sources of volatile organic compounds is reviewed. The biochemical processes associated with these emissions of the compounds and the atmospheric chemistry of the emitted compounds are discussed.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/92GB02125%4010.1002/%28ISSN%291944-9224.NATSOUR1

Emissions of volatile organic compounds from vegetation and the implications for atmospheric chemistry

Objectives: To determine which antecedent infections are specifically associated with the Guillain-Barre syndrome (GBS). Background: Infections with many agents have been reported preceding GBS. Some infections are related to specific clinical and immunologic subgroups in GBS. Most agents were reported in case reports and uncontrolled small series of GBS patients only, and their relation to GBS and its subgroups remains unclear. Methods: A serologic study for 16 infectious agents in 154 GBS patients and 154 sex- and age-matched controls with other neurologic diseases. Acute phase, pretreatment samples were used from clinically well-defined GBS patients. The seasonal distribution of serum sampling in the GBS and control group was the same. Results: Multivariate analysis showed that in GBS patients, infections with Campylobacter jejuni (32%), cytomegalovirus (13%), and Epstein-Barr virus (10%) were significantly more frequent than in controls. Mycoplasma pneumoniae infections occurred more often in GBS patients (5%) than in controls in univariate analysis. Infections with Haemophilus influenzae (1%), parainfluenza 1 virus (1%), influenza A virus (1%), influenza B virus (1%), adenovirus (1%), herpes simplex virus (1%), and varicella zoster virus (1%) were also demonstrated in GBS patients, but not more frequently than in controls. C. jejuni infections were associated with antibodies to the gangliosides GM1 and GD1b and with a severe pure motor form of GBS. Cytomegalovirus infections were associated with antibodies to the ganglioside GM2 and with severe motor sensory deficits. Other infections were not related to specific antiganglioside antibodies and neurologic patterns. Conclusions: Recent infections with C. jejuni , cytomegalovirus, Epstein-Barr virus, and M. pneumoniae are specifically related to GBS. The variety of infections may contribute to the clinical and immunologic heterogeneity of GBS.

The spectrum of antecedent infections in Guillain-Barré syndrome: A case-control study

Out of sight out of mind

Uncovering Soviet Disasters: Exploring the limits of Glasnost By James E Oberg Robert Hale: 1989 Pp317 £1495

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A little knowledge

Sweet smell of success

The .NET platform offers application developers the means to simplify the code base, reduce development time and make portable, interoperable code. Its ultimate goal is to provide users access to their information anywhere, anytime and on any platform or device. While we are used to accessing information or services on one machine or even on a local network, .NET aims to make it simple to write applications that can access information or services anywhere on the World Wide Web. Building upon the Java experiences, Microsoft has designed an entire technology in an integrated and coherent manner.

Vera Rich

Papers

Out of sight out of mind

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A little knowledge

Sweet smell of success

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