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The Geography of the Internet: Cities, Regions and Internet Infrastructure in Europe, Emmanouil Tranos, Edward Elgar, Cheltenham (2013). ix + 231 pp. £67.50 (hbk). ISBN 978 1 78195 336 5. The Inter...

The results of our study of the motion of a three particle, self-gravitating system in general relativistic lineal gravity is presented for an arbitrary ratio of the particle masses. We derive a canonical expression for the Hamiltonian of the system and discuss the numerical solution of the resulting equations of motion. This solution is compared to the corresponding nonrelativistic and post-Newtonian approximation solutions so that the dynamics of the fully relativistic system can be interpreted as a correction to the one-dimensional Newtonian self-gravitating system. We find that the structure of the phase space of each of these systems yields a large variety of interesting dynamics that can be divided into three distinct regions: annulus, pretzel, and chaotic; the first two being regions of quasiperiodicity while the latter is a region of chaos. By changing the relative masses of the three particles we find that the relative sizes of these three phase space regions changes, and that this deformation can be interpreted physically in terms of the gravitational interactions of the particles. Furthermore, we find that many of the interesting characteristics found in the case where all of the particles share the same mass also appear in our more general study. We find that there are additional regions of chaos in the unequal mass system which are not present in the equal mass case. We compare these results to those found in similar systems.

We consider the problem of three-body motion for a relativistic one-dimensional self-gravitating system. After describing the canonical decomposition of the action, we find an exact expression for the three-body Hamiltonian, implicitly determined in terms of the four coordinates and momentum degrees of freedom in the system. Nonrelativistically these degrees of freedom can be rewritten in terms of a single particle moving in a two-dimensional hexagonal well. We find the exact relativistic generalization of this potential, along with its post-Newtonian approximation. We then specialize to the equal-mass case and numerically solve the equations of motion that follow from the Hamiltonian. Working in hexagonal-well coordinates, we obtain orbits in both the hexagonal and three-body representations of the system, and plot the Poincare sections as a function of the relativistic energy parameter eta. We find two broad categories of periodic and quasiperiodic motions that we refer to as the annulus and pretzel patterns, as well as a set of chaotic motions that appear in the region of phase space between these two types. Despite the high degree of nonlinearity in the relativistic system, we find that the global structure of its phase space remains qualitatively the same as its nonrelativistic counterpart for all values of eta that we could study. However, the relativistic system has a weaker symmetry and so its Poincare section develops an asymmetric distortion that increases with increasing eta. For the post-Newtonian system we find that it experiences a chaotic transition in the interval 0.21

This article reviews where we have come from and where we are going in research on regional growth and development. Our object of study is the region, an imprecise term that has been taken to mean areas as large as small countries or as small as urban regions, although how regions are defined does itself have implications for both theories and the empirics of regional growth. How growth occurs remains a poorly understood process. Clearly the basic ingredients of the neo-classical cookbook are important — growth in capital and labour stocks with technological change — but they are neither enough nor revealing enough. Why does the stock of capital grow at different rates? Why does the labour supply increase? What drives technical progress? What are the roots of spatial dependence? We are fairly certain that the answers to these questions embrace agglomeration economies but they also embrace much more. Innovation is associated with research and development and has an identifiable spatial pattern in relation to highly skilled labour and institutions such as universities. But innovation is not just the result of R&D but also entrepreneurship applied to investment. Labour supply responds to real wage differentials but also to environmental and other amenities. Labour is far more geographically mobile in the New World, however, than it is in the Old.

The results of our study of the motion of a three particle, self-gravitating system in general relativistic lineal gravity is presented for an arbitrary ratio of the particle masses. We derive a canonical expression for the Hamiltonian of the system and discuss the numerical solution of the resulting equations of motion. This solution is compared to the corresponding nonrelativistic and post-Newtonian approximation solutions so that the dynamics of the fully relativistic system can be interpreted as a correction to the one-dimensional Newtonian self-gravitating system. We find that the structure of the phase space of each of these systems yields a large variety of interesting dynamics that can be divided into three distinct regions: annulus, pretzel, and chaotic; the first two being regions of quasiperiodicity while the latter is a region of chaos. By changing the relative masses of the three particles we find that the relative sizes of these three phase space regions changes, and that this deformation can be interpreted physically in terms of the gravitational interactions of the particles. Furthermore, we find that many of the interesting characteristics found in the case where all of the particles share the same mass also appear in our more general study. We find that there are additional regions of chaos in the unequal mass system which are not present in the equal mass case. We compare these results to those found in similar systems.

The NOAO Fundamental Plane Survey (NFPS) is a deep, homogeneous, all‐sky spectroscopic and photometric study of 100 X‐ray selected clusters within 200 h −1 Mpc (z < 0.06) with the principle goal of determining the large‐scale flow of clusters with respect to the CMB. The photometry of tens of thousands of galaxies in two colors (B and R) will yield quantitative morphological information; spectroscopic parameters of early‐type galaxies will include velocity dispersions, line indices, and redshifts. When combined with high‐quality Fundamental Plane parameters, these measurements will shed light on the evolution of galaxies in the cluster and environmental dependences of spectroscopic parameters. Early results include detection of a significant dependence of the Mgb index on cluster‐centric radius for Abell 3558, which can be interpreted as a gradient in metallicity or abundance ratios, but is not compatible with an age gradient. In addition, we have used the photometric catalogues to construct maps of the color‐magnitude scatter as a function of position. Substructures identified in these maps often correspond with known X‐ray/velocity subsystems., The Emergence of Cosmic Structure: Thirteenth Astrophysics Conference, Oct. 7-9, 2002, College Park, Maryland

Handbook of Creative Cities, David Emanuel Andersson, Ake E. Andersson and Charlotta Mellander (Eds), Edward Elgar, Cheltenham (2011). ix + 555 pp. US$270.00. £160.00 (hbk). ISBN 978 1 84980 150 9....

This review describes biosynthesis and excretion of oestrogens in cattle as well as their concentrations in blood and milk during various phases of lactation. Possibilities for endocrinological diagnostic by determination of oestrogens in milk are presented. Furthermore, the biological importance of milk oestrogens for progeny and consumers are discussed.

In Corynebacterium glutamicum the LysE carrier protein exhibits the unique function of exporting L-lysine. We here analyze the membrane topology of LysE, a protein of 236 amino acyl residues, using PhoA- and LacZ-fusions. The amino-terminal end of LysE is located in the cytoplasm whereas the carboxy-terminal end is found in the periplasm. Although 6 hydrophobic domains were identified based on hydropathy analyses, only five transmembrane spanning helices appear to be present. The additional hydrophobic segment may dip into the membrane or be surface localized. We show that LysE is a member of a family of proteins found, for example, in Escherichia coil, Bacillus subtilis, Mycobacterium tuberculosis and Helicobacter pylori. This family, which we have designated the LysE family, is distantly related to two additional protein families which we have designated the YahN and CadD families. These three families, the members of which exhibit similar sizes, hydropathy profiles, and sequence motifs comprise the LysE superfamily. Functionally characterized members of the LysE superfamily export L-lysine, cadmium and possibly quarternary amines. We suggest that LysE superfamily members will prove to catalyze export of a variety of biologically important solutes.

OBJECTIVES: Until 1995, infection with Cyclospora cayetanenis, a parasite that causes gastroenteritis, was diagnosed in the US primarily in overseas travelers; its modes of transmission were largely unknown. In 1995, 45 cases of cyclosporiasis were diagnosed in Florida residents who had no history of recent foreign travel, but an investigation could not pinpoint a source for the parasite. In 1996, a North American outbreak of cyclosporiasis resulted in more than 1400 cases, 180 of them in Florida. The authors investigated the 1996 Florida outbreak to identify the vehicle of transmission. METHODS: The authors conducted a matched case-control study in which each of 86 laboratory-confirmed sporadic cases was matched with up to four controls. They also investigated nine clusters of cases associated with common meals and attempted to trace implicated foods to their countries of origin. RESULTS: In the case control study, eating raspberries was strongly associated with cyclosporiasis (matched odds ratio = 31.9; 95% confidence interval [CI] 7.4, 138.2). In the cluster investigation, raspberries were the only food common to all nine clusters of cases; a summary analysis showed a strong association between consumption of raspberries and confirmed or probable cyclosporiasis (risk ratio = 17.6; 95% CI 1.9, 188.8). Guatemala was the sole country of origin for raspberries served at six of nine events. CONCLUSIONS: Guatemalan raspberries were the vehicle for the 1996 Florida cyclosporiasis outbreak. Cyclospora is a foodborne pathogen that may play a growing role in the etiology of enteric disease in this country as food markets become increasingly international.

The apurinic/apyrimidinic endonucleases (APE) contain several highly conserved sequence motifs. The glutamic acid residue in a consensus motif, LQE96TK98 in human APE (hAPE-1), is crucial because of its role in coordinating Mg2+, an essential cofactor. Random mutagenesis of the inactive E96A mutant cDNA, followed by phenotypic screening in Escherichia coli, led to isolation of an intragenic suppressor with a second site mutation, K98R. Although the Km of the suppressor mutant was about sixfold higher than that of the wild-type enzyme, their kcat values were similar for AP endonuclease activity. These results suggest that the E96A mutation affects only the DNA-binding step, but not the catalytic step of the enzyme. The 3' DNA phosphoesterase activities of the wild-type and the suppressor mutant were also comparable. No global change of the protein conformation is induced by the single or double mutations, but a local perturbation in the structural environment of tryptophan residues may be induced by the K98R mutation. The wild-type and suppressor mutant proteins have similar Mg2+ requirement for activity. These results suggest a minor perturbation in conformation of the suppressor mutant enabling an unidentified Asp or Glu residue to substitute for Glu96 in positioning Mg2+ during catalysis. The possibility that Asp70 is such a residue, based on its observed proximity to the metal-binding site in the wild-type protein, was excluded by site-specific mutation studies. It thus appears that another acidic residue coordinates with Mg2+ in the mutant protein. These results suggest a rather flexible conformation of the region surrounding the metal binding site in hAPE-1 which is not obvious from the X-ray crystallographic structure.

This report documents the history of armored vehicle smoke/obscurant protection using grenades and dischargers in rapid obscuration systems in the United States. The history begins with the response to the Arab-Israeli conflicts and the threats of the 196Os and ends with the technology and hardware advances made to deal with threats of the year 2000.

Stanley D. Brunn, Susan L. Cutter, and J. W. Harrington, Jr., eds. Dordrecht, the Netherlands: Kluwer. 2004. xxxii+ 613 pp., color plates, tables, figs., and index. $204.00 cloth (ISBN 1-4020-1857-...

This chapter examines three concepts central to the changes evident in the world economy, and their impacts on regions and places, firms, and people. Technology is perhaps the most important of the three because it has the broadest scope and thus directly affects the other two concepts: flexibility and competitiveness. Technology also is the one least able to be controlled by individual firms, since technology originates in other firms, especially competitors, and in research institutes and universities throughout the world. However, technology provides only a portion of the advantages described as flexibility or as competitiveness. All three are central phenomena of the 1990s, where global capitalist competition has pushed small firms to be international and seek out export markets, and pushed large, transnational firms to form networks of partners, large and small, that allow them to become flexible.

Roger Hayter and Richard Le Heron, eds. Burlington, VT: Ashgate, 2002. xvii and 420 pp., maps, diags., notes, and index. $89.95 cloth (ISBN 0-75463-052-8). A more international examination of some ...

Corporate research and development (R&D) and knowledge networks of large and small firms are responding to widespread availability of talent and diverse knowledge. Much of this dispersed knowledge arises from entrepreneurial activity, originating in universities, research institutes and small and medium-sized enterprises (SMEs). Three important approaches have been introduced recently to understand R&D strategy in the context of global or metanational networks: open innovation, knowledge integration and a double network structure. The contribution of this paper is to analyse these approaches as affecting and affected by the presence of regional innovative ecosystems and their attraction as locations of R&D. This suggests a simultaneous need for local and global, as well as internal and external, knowledge integration.

Research on entrepreneurship has only partially dealt with the influence of geographical environments on the new firms' formation and growth. This paper reviews what we know and what we do not yet know about the ways in which the new firms' formation is not equally likely everywhere, why some places are entrepreneurial and why others places are not so entrepreneurial. Finally, it addresses the ways in which local environments can be improved.

NOTCH1 is a type I transmembrane receptor that regulates T cell development via a signaling pathway that relies on regulated proteolysis. During its maturation, most NOTCH1 is cleaved at a position 70 amino acids external to the transmembrane domain by a furin-like protease, creating extracellular (NEC) and transmembrane (NTM) subunits that are held together non-covalently by a juxtamembranous heterodimerization (HD) domain. Ligand-binding to NEC promotes cleavage by i) metalloproteases at a site in the ectodomain of NTM, followed by ii) gamma-secretase within the transmembrane domain. This releases the NOTCH1 intracellular domain (ICN1), allowing it to translocate to the nucleus and activate target genes. Normally, proteolysis is constrained prior to ligand-binding by an extracellular negative regulatory region consisting of 3 iterated LNR repeats and the N- and C-terminal portions of the HD domain, which flank the furin cleavage site. Recent work has shown that human T-ALL is frequently associated with gain of function mutations that map to the HD domain of NOTCH1. These mutations are distributed in both parts of the HD domain and include point mutations, short insertions, and deletions, suggesting that there might be variation in their relative strength and the mechanisms by which they act. To investigate these issues, we introduced 16 of the HD domain mutations found in primary T-ALLs or T-ALL cell lines into a full-length NOTCH1 cDNA, and tested their ability to activate a NOTCH sensitive luciferase reporter gene. Except for the "mutation" R1609S, which was found in only one primary T-ALL sample, all of the mutations stimulated NOTCH1 signaling. These increases in signaling were abolished by a gamma-secretase inhibitor and were associated with increased rates of metalloprotease-mediated cleavage, indicating that activation proceeds through the normal series of proteolytic events. The mutations also caused gains in function when introduced into NOTCH1 polypeptides lacking the ligand-binding region of NEC, indicating that the HD domain mutations can cause ligand-independent receptor activation. Since NEC dissociation can lead to activation of NOTCH signaling (and is a proposed mechanism for normal ligand-mediated NOTCH activation), one simple way for HD domain mutations to act is through the destabilization of NOTCH1 heterodimers. To test this model, each mutation was introduced into soluble NOTCH1 mini-receptors bearing N-terminal FLAG and C-terminal HA tags. When expressed transiently, the normal NOTCH1 mini-receptor was secreted into conditioned media as a furin-processed heterodimer. Certain activating HD domain mutations, such as L1601P, resulted in complete dissociation of the furin-processed mini-receptor subunits under native conditions, and all other HD domain mutations save one were more sensitive to urea-induced dissociation than normal NOTCH1. The exception was an unusual insertional mutation (identified in the P12-Ichikawa cell line) that introduces a 14 amino acid direct repeat sequence at a position immediately N-terminal of the metalloprotease cleavage site. We hypothesize that this mutation, which was associated with the greatest increases in signaling in NOTCH1 reporter gene assays, displaces protective HD and LNR domain residues and thereby unveils the metalloprotease cleavage site. We conclude that most T-ALL-associated HD domain mutations confer ligand-independent gain-of-function on NOTCH1 receptors, but vary in strength and are likely to act through several distinct mechanisms.

The diffusion of innovations used by firms themselves and those marketed to consumers are considered within a single framework based on the firm. This framework is represented by a general model which balances innovative and aggressive behavior, common to small firms, against the ability to bear the cost and risk of innovation adoption more common to large firms. A similar model for city-size diffusion patterns, based on the fact that large cities are risk-minimizing locations, contrasts with traditional hierarchical models which assume that large cities are usually the sites of first adoption. Examples of two innovations in the American banking industry were analyzed to test the models. The results suggest that traditional strict size-ordered models for firms and urban systems are not always appropriate, especially for innovations by firms.

Industrial geography has expanded beyond manufacturing, and various systems frameworks have been proposed to organize research. Industrial systems, urban and regional systems, and the world system all have some degree of applicability as explanatory devices. The papers in this issue of Environment and Planning A are introduced within the context of recent research in industrial geography.

One of the fundamental aspects of “high technology” is its reliance on people. The high-tech context permits a reexamination of several elements of regional research and policy, including technical workers, entrepreneurship, the effect of new technology in the workplace, and the potential for public policies to address people-related issues. This paper suggests that an orientation toward people relates more accurately to the underlying processes, particularly those that focus on flows of people and information. Entrepreneurship, for example, depends critically on people and their social networks. Likewise, the level of technology in a region or nation is defined by the stock of knowledge and skills found within firms and people. A long-term perspective is necessary for public policies that address regional competitiveness.

This paper analyzes the interrelationships of city size and growth in the American Midwest from 1940 to 1970 in an effort to synthesize the study of urban growth rates and of city-size distributions. Changes in the rank–size distribution are related to the differential growth of different-size urban places; some relationship in changes over time is evident, but there is little correspondence in static analyses. The urban system analyzed by various threshold sizes examines the sensitivity of rank–size coefficients and urban growth-rate stability to the threshold. The threshold size appears to be far more important than previous research has considered, and noticeably influences the analysis of urban growth rates and rank–size distributions.

It is shown that a system of N (N to infinity ) hard discs (of diameter sigma ) in a narrow box, of width D (D< square root 3 sigma ) and length L=Nl, is unstable for a certain range of D and l when D is variable.

Because of their rich and abundant reserve base, the western states of the USA are currently the focus of a major national effort to increase domestic energy production. A number of important problems, however, have arisen in siting the energy facilities which are needed to convert the region's energy resources into end-use fuels or electricity. Many of these siting problems are unique to the region and must be addressed if plans to exploit the energy resources of the western states are to be realized. Careful planning may assist in the siting process and reduce the undesirable impacts of energy conversion plants.

This paper reviews the literature on the role of technology and technological change in regional development. Three specific themes are identified. First, traditional approaches to technology include those found in models of regional growth, in analyses of innovation diffusion, and in economic analysis of technological change. Second, recent research on regional development has involved technology from two perspectives—that of regional economic structure and that of innovation in the strategies and management of large corporations. Third, the underdevelopment of Third World countries has been attributed in part to technological dependence. The possibilities are abundant for research that would add to current understanding of regional development in an age of rapid technological change.