A thousand years before Isaac Asimov set down his Three Laws of Robotics, real and imagined automata appeared in European courts, liturgies, and literary texts. Medieval robots took such forms as ...talking statues, mechanical animals, and silent metal guardians; some served to entertain or instruct while others performed disciplinary or surveillance functions. Variously ascribed to artisanal genius, inexplicable cosmic forces, or demonic powers, these marvelous fabrications raised fundamental questions about knowledge, nature, and divine purpose in the Middle Ages.
Medieval Robotsrecovers the forgotten history of fantastical, aspirational, and terrifying machines that especially captivated Europe in imagination and reality between the ninth and fourteenth centuries. E. R. Truitt traces the different forms of self-moving or self-sustaining manufactured objects from their earliest appearances in the Latin West through centuries of mechanical and literary invention. Chronicled in romances and song as well as histories and encyclopedias, medieval automata were powerful cultural objects that probed the limits of natural philosophy, illuminated and challenged definitions of life and death, and epitomized the transformative and threatening potential of foreign knowledge and culture. This original and wide-ranging study reveals the convergence of science, technology, and imagination in medieval culture and demonstrates the striking similarities between medieval and modern robotic and cybernetic visions.
In his major works for the pope, as well as several other works from his maturity, Bacon focused on the utility of natural knowledge, both in terms of human know-how and what that know-how could ...produce. He looked to the courtly sciences (such as medicine, astral science, optics, and material science), which privilege application and knowledge gained through the sensorium, as sources of natural knowledge and as exemplars for the potential of natural knowledge. This essay argues that Roger Bacon’s work ought to be understood within the context of the court. Bacon’s emphasis on devices in the pursuit of knowledge and utility demonstrates the extent to which the courtly sciences (such as engineering, navigation, alchemy, and divination) were valued alongside traditional natural philosophical frameworks, and need to be understood in that context. Both the courtly sciences and Bacon’s theory of scientia experimentalis focus on materials, sensory knowledge, and knowledge of particulars in pursuit of applied ends. Bacon drew inspiration from the courtly sciences in theorizing how natural knowledge could serve ruling power. By examining Bacon’s major works on scientia experimentalis and analyzing his reliance on examples from the history of Alexander the Great, this essay demonstrates the interrelation of political power and erudite knowledge, and how they intersected through the cultivation and application of experimentum and technology. Finally, Bacon’s interest in the utility of knowledge suggests that courtly settings in this period are significant locations for the development and applications of natural knowledge.
The legend of Gerbert of Aurillac’s oracular head reveals significant information about contemporary medieval attitudes toward foreign knowledge from outside of the Latin Christian West, and in ...particular about the quadrivium, astral science, and celestial divination. In particular, William of Malmesbury’s account—the most well-known in the medieval period—demonstrates the extent to which scientific knowledge from the Arabic tradition had penetrated the intellectual climate of England in the early twelfth century.
Introduction
Measurement of serum acetaminophen-protein adducts (APAP-CYS) has been suggested to support or refute a diagnosis of acetaminophen (APAP)-induced hepatotoxicity when ingestion histories ...are unreliable or unavailable and when circulating APAP concentrations are low or undetectable. Non-APAP overdose patients commonly have used APAP products in non-toxic quantities and, thus, will have measurable APAP-CYS concentrations, even when hepatic injury results from other causes, such as ischemic hepatitis. The relationship between alanine aminotransferase (ALT) activity and APAP-CYS concentration might assist in distinguishing between toxic and non-toxic APAP doses in patients suspected of drug overdose.
Methods
We measured serial levels of serum APAP-CYS and ALT activities in 500 overdose patients in whom APAP toxicity was suspected on inpatient admission, but who were then classified at time of discharge and before results of APAP-CYS concentrations were available into three groups: 1) definite APAP group; 2) definitely not APAP group; and 3) indeterminate group. Subjects in the definite and definitely not APAP groups were selected in whom a plasma ALT activity was measured within ± 4 h of a serum APAP-CYS concentration. Regressions with correlation coefficients between APAP-CYS and ALT were calculated for repeat measures in the 335 subjects (908 blood samples) in the definite APAP group and 79 subjects (231 samples) in the definitely not APAP group, with an emphasis on APAP-CYS concentrations and calculation of 95% prediction intervals when ALT was ≥ 1000 IU/L.
Results
A strong correlation was found between APAP-CYS and ALT in the definite APAP group over all ALT activities (
r
= 0.93,
p
< 0.001;
N
= 335), and when ALT was > 1000 IU/L (
r
= 0.82,
p
< 0.001,
N
= 144). In the 79 definitely not APAP subjects, no significant correlation was found when ALT exceeded 1000 IU/L (
r
= 0.04;
p
= 0.84,
N
= 32). All subjects in the definitely not APAP group displayed APAP-CYS concentrations < 3 μM. In definitely not APAP subjects, the great majority of APAP-CYS levels were below the 95% prediction interval for APAP-CYS concentrations in definite APAP group subjects when ALT was ≥ 1000 IU/L. However, some definitely not APAP group subjects who had ingested non-toxic doses of APAP displayed APAP-CYS concentrations as high as 2.8 μM in the face of ALT elevation from ischemic hepatitis.
Conclusion
The interpretation of serum APAP-CYS concentrations must always be made in light of detailed clinical information and the population being tested, especially because of some overlap in APAP-CYS levels in subjects with and without APAP toxicity.
γ-Alumina surfaces dehydrated at 450 and 700 °C were studied by using the conventional pyridine adsorption-DRFTIR technique. Three types of Lewis acid sites are present on the surface, and in each ...case pyridine adsorbed on them is concomitantly interacting with their adjacent OH groups. Because only three types of Lewis acid sites are present, only three hydrogen bonding bands were observed upon pyridine adsorption. From correlation of OH bands with hydrogen bonding bands, it is found that weak Lewis acid sites have type II66 or II64 OH groups as their neighbors, medium strong Lewis acid sites have type III OH groups near by, and strong Lewis acid sites have type I6 OH groups next to them. Dehydration at 700 °C generates more types of OH groups that also interact with pyridine. The reactivity of OH groups is not determined by their acidity and space restrictions, but rather by their proximity to Lewis acid sites. We assigned the three types of Lewis acid sites to five-, four-, and three-coordinate Al3+ ions.
Natural killer (NK) cells recognize and eliminate infected and malignant cells. Their life histories are poorly understood, particularly in humans, due to lack of informative models and endogenous ...clonal markers. Here, we apply transplantation of barcoded rhesus macaque hematopoietic cells to interrogate the landscape of NK cell production, expansion, and life histories at a clonal level long term and after proliferative challenge. We identify oligoclonal populations of rhesus CD56
CD16
NK cells that are characterized by marked expansions and contractions over time yet remained long-term clonally uncoupled from other hematopoietic lineages, including CD56
CD16
NK cells. Individual or groups of CD56
CD16
expanded clones segregated with surface expression of specific killer immunoglobulin-like receptors. These clonally distinct NK cell subpopulation patterns persisted for more than 4 years, including after transient in vivo anti-CD16-mediated depletion and subsequent regeneration. Profound and sustained interleukin-15-mediated depletion was required to generate new oligoclonal CD56
CD16
NK cells. Together, our results indicate that linear NK cell production from multipotent hematopoietic progenitors or less mature CD56
CD16
cells is negligible during homeostasis and moderate proliferative stress. In such settings, peripheral compartmentalized self-renewal can maintain the composition of distinct, differentiated NK cell subpopulations.
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