The Golden Staph : medicine's response to the challenge of the resistant staphilococci in the mid-twentieth century

During ttie first two decades of the antibiotic era the problem of microbia! resistance to antibiotic therapy was discovered, challenged and, iri part, the battle was wori. The chemotherapeutic agents, antibiotics, werc often touted as ((miracle drugs)), but were not without severe tests arid riot unconinion lost skirmishes. The refractory resistance of one particular pathogen, Staphylococcus aureus, the Golden Staph, was to cause corisidcrable difficulties for the new medicine of the 1940s and 1950s. It secarried that rio sooner had penicillin become available than Charles Rarrinielkarrip (b. 191 l), one of the first phvsicians to employ it, discovcred resistarice to its antimicrobial abilities (1)

Self-Sustaining Oscillations in Complex Networks of Excitable Elements

Random networks of symmetrically coupled, excitable elements can self-organize into coherently oscillating states if the networks contain loops (indeed loops are abundant in random networks) and if the initial conditions are sufficiently random. In the oscillating state, signals propagate in a single direction and one or a few network loops are selected as driving loops in which the excitation circulates periodically. We analyze the mechanism, describe the oscillating states, identify the pacemaker loops and explain key features of their distribution. This mechanism may play a role in epileptic seizures.Comment: 5 pages, 4 figures included, submitted to Phys. Rev. Let

The importance of cross-validation, accuracy, and precision for measuring plumage color: A comment on Vaquero-Alba et al. (2016)

Vaquero-Alba and colleagues published a study in The Auk: Ornithological Advances comparing objective color measurements of plumage taken in the field directly on a bird’s body to those taken in the lab on collected feathers arranged to emulate the appearance of a bird’s natural plumage. Although the field measures of plumage color were less repeatable than lab measures, the authors concluded that measurements taken in the field were more representative of a bird’s ‘‘true color.’’ Accordingly, they recommend that researchers should bring spectrophotometers into the field to measure color on live birds. We question the assumption that their field measurements represent true color and highlight concerns regarding their experimental design and methodology. Because they did not measure color of live birds in the lab or the color of plucked feathers in the field, they cannot directly test whether the assessment of color in the field on a live bird is superior. Also, rather than assume field measures are the most accurate or precise way to assess plumage color, we suggest cross-validation with other methodologies, such as digital photography, pigment biochemistry, or measures of a known color standard in both environments. Importantly, researchers should be aware of the limitations and advantages of various methods for measuring plumage color so they can use the method most appropriate for their study. Vaquero-Alba y sus colaboradores publicaron un estudio en The Auk comparando medidas objetivas del color del plumaje tomadas en el campo directamente en el cuerpo del ave con medidas tomadas en el laboratorio en plumas recolectadas y organizadas para emular la apariencia natural del plumaje. Aunque las medidas de campo del color del plumaje fueron menos repetibles que las de laboratorio, los autores concluyeron que las medidas tomadas en el campo fueron ma´s representativas del ‘‘color verdadero’’ de un ave. En consecuencia, recomendaron que los investigadores deben llevar espectrofot ´ ometros a los sitios de campo para medir el color en aves vivas. Cuestionamos la suposici ´on de que sus mediciones de campo representan el ‘‘color verdadero’’ y resaltamos nuestras preocupaciones con respecto a su dise ˜no experimental y metodolog´ıa. Debido a que ellos no midieron el color de las aves vivas en el laboratorio ni el color de las plumas sueltas en el campo, no pueden evaluar directamente si la evaluaci ´on del color en el campo en un ave viva es superior. Tambi´en, en vez de asumir que las medidas de campo son la forma ma´s exacta o precisa de determinar el color del plumaje, sugerimos que se haga una validaci ´on cruzada con otras metodolog´ıas como la fotograf´ıa digital, la bioqu´ımica de los pigmentos o las medidas de un esta´ndar de un color conocido en ambos ambientes. Es importante que los investigadores tengan en cuenta las limitaciones y avances en varios m´etodos para medir el color del plumaje para que puedan usar el m´etodo ma´s apropiado para su estudio

The importance of cross-validation, accuracy, and precision for measuring plumage color: A comment on Vaquero-Alba et al. (2016)

Vaquero-Alba and colleagues published a study in The Auk: Ornithological Advances comparing objective color measurements of plumage taken in the field directly on a bird’s body to those taken in the lab on collected feathers arranged to emulate the appearance of a bird’s natural plumage. Although the field measures of plumage color were less repeatable than lab measures, the authors concluded that measurements taken in the field were more representative of a bird’s ‘‘true color.’’ Accordingly, they recommend that researchers should bring spectrophotometers into the field to measure color on live birds. We question the assumption that their field measurements represent true color and highlight concerns regarding their experimental design and methodology. Because they did not measure color of live birds in the lab or the color of plucked feathers in the field, they cannot directly test whether the assessment of color in the field on a live bird is superior. Also, rather than assume field measures are the most accurate or precise way to assess plumage color, we suggest cross-validation with other methodologies, such as digital photography, pigment biochemistry, or measures of a known color standard in both environments. Importantly, researchers should be aware of the limitations and advantages of various methods for measuring plumage color so they can use the method most appropriate for their study. Vaquero-Alba y sus colaboradores publicaron un estudio en The Auk comparando medidas objetivas del color del plumaje tomadas en el campo directamente en el cuerpo del ave con medidas tomadas en el laboratorio en plumas recolectadas y organizadas para emular la apariencia natural del plumaje. Aunque las medidas de campo del color del plumaje fueron menos repetibles que las de laboratorio, los autores concluyeron que las medidas tomadas en el campo fueron ma´s representativas del ‘‘color verdadero’’ de un ave. En consecuencia, recomendaron que los investigadores deben llevar espectrofot ´ ometros a los sitios de campo para medir el color en aves vivas. Cuestionamos la suposici ´on de que sus mediciones de campo representan el ‘‘color verdadero’’ y resaltamos nuestras preocupaciones con respecto a su dise ˜no experimental y metodolog´ıa. Debido a que ellos no midieron el color de las aves vivas en el laboratorio ni el color de las plumas sueltas en el campo, no pueden evaluar directamente si la evaluaci ´on del color en el campo en un ave viva es superior. Tambi´en, en vez de asumir que las medidas de campo son la forma ma´s exacta o precisa de determinar el color del plumaje, sugerimos que se haga una validaci ´on cruzada con otras metodolog´ıas como la fotograf´ıa digital, la bioqu´ımica de los pigmentos o las medidas de un esta´ndar de un color conocido en ambos ambientes. Es importante que los investigadores tengan en cuenta las limitaciones y avances en varios m´etodos para medir el color del plumaje para que puedan usar el m´etodo ma´s apropiado para su estudio

A Global Analog of Cheshire Charge

It is shown that a model with a spontaneously broken global symmetry can support defects analogous to Alice strings, and a process analogous to Cheshire charge exchange can take place. A possible realization in superfluid He-3 is pointed out.Comment: 24 pages (figures 1-4 included as uu-encoded tar files), CALT-68-1865 (Revised version: an expression (eq. 17) for global charge density is corrected; some typos and sign mismatches are removed.

Software security requirements engineering: State of the art

Software Engineering has established techniques, methods and technology over two decades. However, due to the lack of understanding of software security vulnerabilities, we have not been so successful in applying software engineering principles that have been established for the past at least 25 years, when developing secure software systems. Therefore, software security can not be just added after a system has been built and delivered to customers as seen in today’s software applications. This keynote paper provides concise methods, techniques, and best practice requirements guidelines on software security and also discusses an Integrated-Secure SDLC model (IS-SDLC), which will benefit practitioners, researchers, learners, and educators

Static analysis-based approaches for secure software development

Software security is a matter of major concern for software development enterprises that wish to deliver highly secure software products to their customers. Static analysis is considered one of the most effective mechanisms for adding security to software products. The multitude of static analysis tools that are available provide a large number of raw results that may contain security-relevant information, which may be useful for the production of secure software. Several mechanisms that can facilitate the production of both secure and reliable software applications have been proposed over the years. In this paper, two such mechanisms, particularly the vulnerability prediction models (VPMs) and the optimum checkpoint recommendation (OCR) mechanisms, are theoretically examined, while their potential improvement by using static analysis is also investigated. In particular, we review the most significant contributions regarding these mechanisms, identify their most important open issues, and propose directions for future research, emphasizing on the potential adoption of static analysis for addressing the identified open issues. Hence, this paper can act as a reference for researchers that wish to contribute in these subfields, in order to gain solid understanding of the existing solutions and their open issues that require further research

Free Radical Exposure Creates Paler Carotenoid-Based Ornaments: A Possible Interaction in the Expression of Black and Red Traits

Oxidative stress could be a key selective force shaping the expression of colored traits produced by the primary animal pigments in integuments: carotenoids and melanins. However, the impact of oxidative stress on melanic ornaments has only recently been explored, whereas its role in the expression of carotenoid-based traits is not fully understood. An interesting study case is that of those animal species simultaneously expressing both kinds of ornaments, such as the red-legged partridge (Alectoris rufa). In this bird, individuals exposed to an exogenous source of free radicals (diquat) during their development produced larger eumelanin-based (black) plumage traits than controls. Here, we show that the same red-legged partridges exposed to diquat simultaneously developed paler carotenoid-based ornaments (red beak and eye rings), and carried lower circulating carotenoid levels as well as lower levels of some lipids involved in carotenoid transport in the bloodstream (i.e., cholesterol). Moreover, partridges treated with a hormone that stimulates eumelanin production (i.e., alpha-melanocyte-stimulating hormone) also increased blood carotenoid levels, but this effect was not mirrored in the expression of carotenoid-based traits. The redness of carotenoid-based ornaments and the size of a conspicuous eumelanic trait (the black bib) were negatively correlated in control birds, suggesting a physiological trade-off during development. These findings contradict recent studies questioning the sensitivity of carotenoids to oxidative stress. Nonetheless, the impact of free radicals on plasma carotenoids seems to be partially mediated by changes in cholesterol metabolism, and not by direct carotenoid destruction/consumption. The results highlight the capacity of oxidative stress to create multiple phenotypes during development through differential effects on carotenoids and melanins, raising questions about evolutionary constraints involved in the production of multiple ornaments by the same organism

Adoption of BIM by architectural firms in India: technology–organization–environment perspective

Building information modelling (BIM) is being heralded as a remarkable innovation in the built environment sector with expectations of lofty sector-wide improvements. Some countries have shown remarkable levels of uptake of BIM, along the way documenting some evidence of benefits stemming from BIM. However, countries such as India and China are late entrants in the BIM adoption journey and are seeing a slower adoption rate. This study develops a model using the technology–organization–environment framework to study the factors influencing BIM adoption by architectural firms in India and reasons for this slow adoption. The proposed model of BIM adoption is tested using the partial least square method against responses collected from 184 industry professionals based in India. Findings reveal that the adoption of BIM by Indian architectural firms is at the ‘experimentation’ stage with variables such as expertise, trialability, and management support exhibiting a strong positive influence on BIM adoption. The study also explains the status of BIM adoption in India with the help of a multi-level social construct, which places the level of BIM adoption in India between the micro- and meso-levels of organizational scales. Similarities and dissimilarities with previous findings are discussed in the paper to highlight the findings of this study. © 2016 Informa UK Limited, trading as Taylor & Francis Grou