The conquest of the dark spaces: An experimental approach to lighting systems in Paleolithic caves.

Artificial lighting was a crucial physical resource for expanding complex social and economic behavior in Paleolithic groups. Furthermore, the control of fire allowed the development of the first symbolic behavior in deep caves, around 176 ky BP. These activities would increase during the Upper Paleolithic, when lighting residues proliferated at these sites. The physical peculiarities of Paleolithic lighting resources are very poorly understood, although this is a key aspect for the study of human activity within caves and other dark contexts. In this work, we characterize the main Paleolithic lighting systems (e.g., wooden torches, portable fat lamps, and fireplaces) through empirical observations and experimental archeology in an endokarstic context. Furthermore, each lighting system's characteristic combustion residues were identified to achieve a better identification for the archaeological record. The experiments are based on an exhaustive review of archaeological information about this topic. Besides, we apply the estimated luminous data of a Paleolithic cave with Paleolithic art (Atxurra in northern Spain) in 3D through GIS technology to delve into the archeologic implications of illumination in Paleolithic underground activities.

LEDs for photons, physiology and food.

Lighting based on light-emitting diodes (LEDs) not only is more energy efficient than traditional lighting, but also enables improved performance and control. The colour, intensity and distribution of light can now be controlled with unprecedented precision, enabling light to be used both as a signal for specific physiological responses in humans and plants, and as an efficient fuel for fresh food production. Here we show how a broad and improved understanding of the physiological responses to light will facilitate greater energy savings and provide health and productivity benefits that have not previously been associated with lighting.

Origins of the binocular head mirror: The mystery of Dr. Clar, clarified.

BACKGROUND: The origin of Dr. Clar's forehead mirror remains a mystery. The aim of this study is to track the roots of this eponym anew to find a definitive answer. METHODS: Historical, notably by the analysis of the reports of medical meetings and the content of instrument trade catalogs of the corresponding epoch. RESULTS: Konrad or Conrad Clar (1844-1904) was an Austrian balneologist and geologist particularly interested in laryngological examination. He notably invented a lighting apparatus in 1874, his famous forehead mirror in 1886, and a handgrip for laryngological instruments in 1901. CONCLUSIONS: Konrad Clar is the man behind the eponymous Dr. Clar's mirror. This study allowed to definitively confirm this statement.

Clar as Mud? Origins of the head mirror: A historical note.

In Europe, the name "Clar" immediately evokes to any otorhinolaryngologist the classic head mirror that remains a symbol of our profession. Yet, the origin of Clar has never been investigated. In this clinical and historical review, based on an Internet and PubMed database search together with perusal of Fischer's Biographical Lexikon, the authors seek to elucidate this medical enigma. The data presented suggest that Clar was not a physician but rather a term picked by the company that designed the mirror by the end of the 19th century to underscore the bright and sharp view provided by this then innovative medical device. © 2015 Wiley Periodicals, Inc. Head Neck 38: 930-932, 2016.

Shining new light on the Hawthorne illumination experiments.

OBJECTIVE: This study provides an historical and statistical analysis of archival data from the Hawthorne illumination experiments. BACKGROUND: Previous accounts of the illumination experiments are fraught with inconsistencies because they have been based on secondary sources. The general consensus has been that variations in light levels had no effect on worker productivity at Hawthorne. All reports and data were thought to have been destroyed, but an archive at Cornell University was found to contain copies of the original documentation and much of the data from all three illumination experiments. Conclusions were originally drawn from visual comparisons of productivity graphs, and the data have never been properly statistically analyzed. METHOD: Archival reports, notes, photographs, and letters on the experiments were consulted. Productivity data were extracted from the tables and graphs in the reports and statistically analyzed for each experiment. RESULTS: Previously unpublished details of the illumination experiments emerged. An effect of lighting on productivity was found in the first treatment sequence for the first experiment, but this finding was not confirmed in the second sequence or in the second and third experiments. CONCLUSION: Experimental results provided inconsistent evidence of an association between light levels and productivity. All three experiments were found to be seriously flawed. APPLICATION: This study challenges popular accounts of the "Hawthorne effect," and the shortcomings of these experiments also have implications for the design of field studies.

Circadian desynchrony and metabolic dysfunction; did light pollution make us fat?

Circadian rhythms are daily oscillations in physiology and behaviour that recur with a period of 24h, and that are entrained by the daily photoperiod. The cycle of sunrise and sunset provided a reliable time cue for many thousands of years, until the advent of artificial lighting disrupted the entrainment of human circadian rhythms to the solar photoperiod. Circadian desynchrony (CD) occurs when endogenous rhythms become misaligned with daily photoperiodic cycles, and this condition is facilitated by artificial lighting. This review examines the hypothesis that chronic CD that has accompanied the availability of electric lighting in the developed world induces a metabolic and behavioural phenotype that is predisposed to the development of obesity. The evidence to support this hypothesis is based on epidemiological data showing coincidence between the appearance of obesity and the availability of artificial light, both geographically, and historically. This association links CD to obesity in humans, and is corroborated by experimental studies that demonstrate that CD can induce obesity and metabolic dysfunction in humans and in rodents. This association between CD and obesity has far reaching implications for human health, lifestyle and work practices. Attention to the rhythmicity of daily sleep, exercise, work and feeding schedules could be beneficial in targeting or reversing the modern human predisposition to obesity.

The paradoxes of patenting at General Electric: Isador Ladoff's journey from Siberian exile to the heart of corporate capitalism.

Isador Ladoff (1857-1918) worked briefly in the General Electric Company Research Laboratory, from 1901 to 1903. Since he was not employed to invent, Ladoff maintained that he, not the company, owned his invention of a new arc lamp electrode, eventually winning his case on appeal in 1911. The conduct and course of this patent litigation are examined in the light of Ladoff's remarkable life as a prisoner of the czar in Siberia before his escape to the United States in 1891 and as a socialist activist and writer thereafter. In showing that Ladoff's socialist principles activated his struggle with GE, the essay brings out the ironies of his defense of individualism against the incipient socialism of the laboratory supposedly espoused by officials of the company. The case is interesting in relation to the shift from the ideology, and the reality, of heroic individual invention to that of corporate invention in U.S. industrial research. That shift in turn was a crucial landmark in the longer history of the place of science in negotiation and contest about the relationship between creativity and intellectual property.

Desreza dmostrada y conocimento distorsionado: Lo amateur y la precisión en la España de finales del siglo XVIII / Displayed dexterity and distorted knowledge: Amateurism and precision in late 18TH century Spain

This paper explores the links between scientific practice and precision both in expert networks and popular literature in the second half 18th century Spain. It will be argued that scientific instruments were used and understood in different ways in these two networks, which required opposing strategies for visualizing the degree and goodness of users’ dexterities, thereby fostering the emergence of different collective and individual (epistemic) subjects. I will also argue that these subjects’ differences and affinities were constructed around three themes: firstly, the degree of precision needed to establish a correlation between data and the world, or, in other words, the degree of fluidity admitted in connecting material and cultural worlds; secondly, the relevance attributed to body and bod(il)y knowledge in producing reliable data and stabilizing expertise; and thirdly, the weight attributed to opinion in leaning towards ephemeral or lasting data. The first part of the paper looks at the epistemological and political confluences which in late 18th century Spain nurtured the emergence of both aculture of precision and a sphere of public opinion, and to the strained relationship that existed between them. The other three sections explore how Spanish people used different sets of practices to construct different images of themselves as supporters of a moral of precision (AU)

En este artículo se analiza la relación entre el ejercicio científico y la precisión científica tanto en las redes de expertos como en la literatura popular en la España de la segunda mitad del siglo XVIII. Se mostrará que los instrumentos científicos fueron utilizados y comprendidos de diferentes maneras en estas dos redes, lo cual requirió aplicar unas estrategias opuestas para visualizar el grado y la eficacia de las destrezas de los usuarios, y por lo tanto impulsó la emergencia de diferentes sujetos colectivos e individuales (epistémicos). También demostraré cómo estas diferencias y afinidades de sujetos se construyeron alrededor de tres temas: en primer lugar, el grado de precisión necesario para establecer una correlación entre los datos y el mundo o, en otras palabras, el grado de fluidez admitido para conectar el mundo material y el mundo cultural; en segundo lugar, la importancia atribuida al cuerpo y al conocimiento del cuerpo para producir datos fiables y establecerla experiencia; y en tercer lugar, el peso atribuido a la opinión al respaldarse en datos efímeros o duraderos. La primera parte del artículo se centra en las confluencias epistemológicas y políticas que en la España de finales del siglo XVIII impulsaron la emergencia tanto de una cultura de precisión como de una esfera de opinión pública, y de la tensa relación que existía entre ambas. Los otros tres apartados analizan cómo los españoles utilizaron diferentes conjuntos de prácticas para construir diferentes imágenes de ellos mismos como defensores de una moral de la precisión (AU)