Feedback Control as a Framework for Understanding Tradeoffs in Biology

Control theory arose from a need to control synthetic systems. From regulating steam engines to tuning radios to devices capable of autonomous movement, it provided a formal mathematical basis for understanding the role of feedback in the stability (or change) of dynamical systems. It provides a framework for understanding any system with feedback regulation, including biological ones such as regulatory gene networks, cellular metabolic systems, sensorimotor dynamics of moving animals, and even ecological or evolutionary dynamics of organisms and populations. Here we focus on four case studies of the sensorimotor dynamics of animals, each of which involves the application of principles from control theory to probe stability and feedback in an organism's response to perturbations. We use examples from aquatic (electric fish station keeping and jamming avoidance), terrestrial (cockroach wall following) and aerial environments (flight control in moths) to highlight how one can use control theory to understand how feedback mechanisms interact with the physical dynamics of animals to determine their stability and response to sensory inputs and perturbations. Each case study is cast as a control problem with sensory input, neural processing, and motor dynamics, the output of which feeds back to the sensory inputs. Collectively, the interaction of these systems in a closed loop determines the behavior of the entire system.Comment: Submitted to Integr Comp Bio

Exploring the interplay between Buddhism and career development : a study of highly skilled women workers in Sri Lanka

This article adopts a socio cultural lens to examine the role of Buddhism in highly skilled women workers’ careers in Sri Lanka. While Buddhism enabled women’s career development by giving them strength to cope with difficult situations in work, it also seemed to restrict their agency and constrain their career advancement. Based on our findings, we argue that being perceived as a good Buddhist woman worked as a powerful form of career capital for the respondents in our sample, who used their faith to combat gender disadvantage in their work settings

The role of intrinsic muscle mechanics in the neuromuscular control of stable running in the guinea fowl

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66308/1/jphysiol.2009.171017.pd

Above- and below-ground vertebrate herbivory may each favour a different subordinate species in an aquatic plant community

At least two distinct trade-offs are thought to facilitate higher diversity in productive plant communities under herbivory. Higher investment in defence and enhanced colonization potential may both correlate with decreased competitive ability in plants. Herbivory may thus promote coexistence of plant species exhibiting divergent life history strategies. How different seasonally tied herbivore assemblages simultaneously affect plant community composition and diversity is, however, largely unknown. Two contrasting types of herbivory can be distinguished in the aquatic vegetation of the shallow lake Lauwersmeer. In summer, predominantly above-ground tissues are eaten, whereas in winter, waterfowl forage on below-ground plant propagules. In a 4-year exclosure study we experimentally separated above-ground herbivory by waterfowl and large fish in summer from below-ground herbivory by Bewick’s swans in winter. We measured the individual and combined effects of both herbivory periods on the composition of the three-species aquatic plant community. Herbivory effect sizes varied considerably from year to year. In 2 years herbivore exclusion in summer reinforced dominance of Potamogeton pectinatus with a concomitant decrease in Potamogeton pusillus, whereas no strong, unequivocal effect was observed in the other 2 years. Winter exclusion, on the other hand, had a negative effect on Zannichellia palustris, but the effect size differed considerably between years. We suggest that the colonization ability of Z. palustris may have enabled this species to be more abundant after reduction of P. pectinatus tuber densities by swans. Evenness decreased due to herbivore exclusion in summer. We conclude that seasonally tied above- and below-ground herbivory may each stimulate different components of a macrophyte community as they each favoured a different subordinate plant species

Local Resistance in Early Medieval Chinese Historiography and the Problem of Religious Overinterpretation

Official Chinese historiography is a treasure trove of information on local resistance to the centralised empire in early medieval China (third to sixth century). Sinologists specialised in the study of Chinese religions commonly reconstruct the religious history of the era by interpreting some of these data. In the process, however, the primary purpose of the historiography of local resistance is often overlooked, and historical interpretation easily becomes ‘overinterpretation’—that is, ‘fabricating false intensity’ and ‘seeing intensity everywhere’, as French historian Paul Veyne proposed to define the term. Focusing on a cluster of historical anecdotes collected in the standard histories of the four centuries under consideration, this study discusses the supposedly ‘religious’ nature of some of the data they contain

Parution - Social history of medicine

Parution - Social history of medicine Social history of medicine, Volume 24, Issue 2, August 2011 John Slater and María Luz López Terrada Scenes of Mediation: Staging Medicine in the Spanish Interludes Mitchell Lewis Hammond Medical Examination and Poor Relief in Early Modern Germany Gill Newton Infant Mortality Variations, Feeding Practices and Social Status in London between 1550 and 1750 Russell Noyes, Jr. The Transformation of Hypochondriasis in British Medicine, 1680–1830 Zipora Shehory..

Versteckt wie Anne Frank - Chronik des Gettos Lodz / Litzmannstadt

http://geschichtsunterricht.wordpress.com/2011/08/15/hinweis-auf-zwei-seiten-zum-holocaust macht auf zwei Websites zum Holocaust aufmerksam. http://www.verstecktwieannefrank.de/#/kaart Versteckt wie Anne Frank ist eine Seite, die auf dem Buch Andere achterhuizen beruht und auf einer Karte Verstecke anderer Juden und ihre Fluchtwege in den Niederlanden zeigt. http://www.getto-chronik.de/de Innerhalb der jüdischen Getto-Verwaltung wurde im November 1940 ein Archiv gebildet, zu dessen Aufgaben ..