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Historians of Britain have long targeted the eighteenth century as the moment when male surgeons moved into the birthing room, beginning to deliver babies and supersede midwives. This transition has been attributed to a range of causes, from the technological (the development of obstetrical forceps) to the cultural (man-midwives becoming fashionable). This chapter problematizes these explanations, situates the change in the larger history of women’s work and views the British experience in the wider European context, as well as in British North America and the French Caribbean colony of Saint-Domingue, where men took a variety of roles. In Paris, for example, male surgeons had been crucial innovators in childbirth since the sixteenth century, while in Italy, a few schools for midwives, run by medical men, functioned from the late eighteenth century; even the German university lying-in hospitals trained female midwives as well as the male medical students for whom they were primarily designed. Seen in this pan-European context, the advent of man-midwives becomes, in part, an English version of the Enlightenment project to improve the life-chances of mothers and babies.
The discovery of the ubiquity of filaments in the interstellar medium in the last two decades has begged the question: “What role do filaments play in star formation?” Here we describe how our automated filament finding algorithms can combine with both magnetic field measurements and high-resolution observations of dense cores in these filaments, to provide a statistically large sample to investigate the effect of filaments on star formation. We find that filaments are likely actively accreting mass from the interstellar medium, explaining why some 60% of stars, and all massive stars, form “on-filament”.
Epitaxial layers of insulating binary lanthanide oxides have been considered as potential alternative to conventional SiO2 for gate dielectric application in future Si-based MOSFET devices, which was investigated in more detail for epitaxial Gd2O3 and Nd2O3 as model systems. Additionally, the ability to integrate epitaxial dielectric barrier layers into Si structures can usher also in a variety of novel applications involving oxide/silicon/oxide heterostructures in diverse nanoelectronic and quantum-effect devices. Although epitaxial layers of such ionic oxides with excellent structural quality can be grown using molecular beam epitaxy, they often exhibit poor electrical properties such as high leakage current density, flat band instability, poor reliability etc. owing to the presence of electrically active charge defects, generated either during the oxide layer growth or typical subsequent CMOS process steps. Based on the origin and individual character of these defects, we review various aspects of defect prevention and passivation which lead to a significant improvement in the dielectric properties of the heterostructures.
Despite an intractable judiciary, there is widespread consensus within the legal academy that jury nullification is compatible with the rule of law. This proposition is most strongly tested by “substantive nullifications,” where a jury nullifies simply because it disagrees with the law itself. While some substantive nullifications can comport with the rule of law, most commentators’ wholesale acceptance of the practice is not justified. They err by ignoring the nonsubstantive, procedural nature of the rule of law in favor of one determined by substantive “justice,” and also by taking a naïvely undifferentiated view of a “community's” morality (even though jurisdictional and vicinage morality can diverge). In doing so, a healthy vision of antityrannical nullifications is presented, but this leaves out many problematic cases. Once these errors are rectified, a more nuanced picture emerges, and it becomes apparent that localism will often disrupt the congruence feature of the rule of law.
Women wrote about health, healing and the body in a variety of spaces in early modern England. When we look from the top down, that is from the perspective of a physician, we see few women healers, and even fewer women writers. However, if we start at the bedside, we see women involved in a wide range of healing activities, many of which they preserved in one form of writing or another. In order to understand the kinds of women's writings that have survived, we need to frame those texts in two larger contexts, that of medical work, and that of women's speech. Historians used to think that medical work in early modern England was organized the way that physicians imagined that it should be: with themselves at the top, overseeing their inferiors. We now recognize that vision for the fantasy that it was. There were many kinds of health care providers in early modern England. The basic four clearly identified occupational groups were midwives, apothecaries, surgeons and physicians. Of these, women were eligible for entry only into the ranks of midwives. They were barred from universities and thus from becoming physicians, and they were not apprenticed to surgeons or apothecaries. However, these groups represented only a portion of England's female healers. Many, many others practised in part-time or occasional fashion. Equally if not more important, many women were responsible for the health of their household, diagnosing, prescribing and preparing medicines at home. We will never know the full extent of women's health care practice, but women were a substantial portion of practitioners.
Many materials systems are currently under consideration as potential replacements for SiO2 as the gate dielectric material for sub-0.1 μm CMOS technology. We present results for crystalline gadolinium oxides on silicon in the cubic bixbyite structure grown by solid source molecular beam epitaxy. On Si(100), crystalline Gd2O3 grows usually as (110)-oriented domains, with two orthogonal in-plane orientations. Layers grown under best vacuum conditions often exhibit poor dielectric properties due to the formation of crystalline interfacial silicide inclusions. Additional oxygen supply during growth improves the dielectric properties significantly. Layers grown by an optimized MBE process display a sufficiently high-K value to achieve equivalent oxide thickness values < 1 nm, combined with ultra-low leakage current densities, good reliability, and high electrical breakdown voltage. A variety of MOS capacitors and field effect transistors has been fabricated based on these layers. Efficient manipulation of Si(100) 4° miscut substrate surfaces can lead to single domain epitaxial Gd2O3 layer. Such epi-Gd2O3 layers exhibited significant lower leakage currents compared to the commonly obtained epitaxial layers with two orthogonal domains. For capacitance equivalent thicknesses below 1 nm, this differences disappear, indicating that for ultrathin layers direct tunneling becomes dominating. We investigated the effect of post-growth annealings on layer properties. We showed that a standard forming gas anneal can eliminate flatband instabilities and hysteresis as well as reduce leakage currents by saturating dangling bond caused by the bonding mismatch. In addition, we investigated the impact of rapid thermal anneals on structural and electrical properties of crystalline Gd2O3 layers grown on Si with different orientations. The degradation of layers can be significantly reduced by sealing the layer with amorphous silicon prior to annealing.
From the Renaissance well into the nineteenth century, no ethics particular to medicine governed the patient–practitioner relationship in Europe and North America (see also Chapters 1 and 28). Although elite university-trained practitioners wrote treatises on topics that we now consider under the rubric of medical ethics, the day-to-day relationships between healers and the sick were shaped by two sets of more general social norms. First, the structure of early modern health care provision has been likened to a medical marketplace. In such a marketplace, medicine was a commodity like any other, and so medical interactions were largely structured by the rules of commercial interchange. Second, as in other social relations of the period, both patients and practitioners appreciated the mutual obligations of patronage and deference between people of different social groups. At times, the patient was the patron, and the practitioner a client, whereas at others these roles were reversed. From the seventeenth century, patients were sometimes understood as a group deserving of special protection due to their temporary or permanent disability.
THE MEDICAL MARKETPLACE
Over the past two decades, historians have become interested in the rank-and-file of medical practitioners and in the experiences of patients rather than just the elite of medicine. As a result of this broader canvas, they have come to describe health care provision in early modern Europe and North America as a medical marketplace (see also Chapter 27). Three key features characterize this model.
We investigated the influence of additional oxygen supply and temperature during the growth of thin Gd2O3 layers on Si(001) with molecular beam epitaxy. Additional oxygen supply during growth improves the dielectric properties significantly; however too high oxygen partial pressures lead to an increase in the lower permittivity interfacial layer thickness. The growth temperature mainly influences the dielectric gate stack properties due to changes of the Gd2O3/Si interface structure. Optimized conditions (600 °C, pO2 = 5·10-7 mbar) were found to achieve equivalent oxide thickness values below 1 nm accompanied by leakage current densities below 1 mA/cm2 at 1 V.
Double-barrier insulator/Si/insulator nanostructures on Si(111) were prepared using molecular beam epitaxy. Ultrathin single-crystalline Si buried in a single-crystalline insulator matrix with sharp interfaces was obtained by a novel approach based on an epitaxial encapsulated solid-phase epitaxy. As an example, we demonstrate the growth of Si buried in Gd2O3 and the incorporation of epitaxial Si islands into single-crystalline Gd2O3. The I-V characteristic of the obtained nanostructures exhibited negative differential resistance at low temperatures, however, with a strong memory effect.
Today, science is something we think we recognize when we see it; it is a part of our cultural landscape. Regarded as easily distinguished from religion, it involves the production of new knowledge rather than the reproduction of faith. Science’s stated mission is to tell truths about the natural world – truths produced by trained scientists working in specific fields. There is much argument about details, but a single method is held to lie at the heart of its production.
The processes by which new scientific knowledge is diffused or reformulated for different audiences are also generally regarded as unproblematic. First elaborated and validated in specialist journals, scientific ideas are usually thought to make their way into undergraduate textbooks and subsequently, or simultaneously, undergo popularization or reframing for a wide audience. Newspapers, magazines, television, and radio help perform the task. Ultimately, a few scientific ideas become so widespread that they can be referred to in the shorthand of jokes or cartoons.
This commonsense model of the production and diffusion of scientific knowledge is something like a fried egg, sunny-side up. At the center, the self-contained yolk represents new knowledge generated by scientists. Surrounding this is a penumbra of ever-thinning white, representing diffusion. Finally, the crackly bits at the outer edge of the white – those jokes and catchphrases – barely resemble the self-contained yolk. As another historian has described it, the transfer of scientific knowledge is often seen simplistically as moving from areas of high truth concentration to those of low truth concentration.
We show results for molecular beam epitaxial (MBE) growth of praseodymium oxide on Si. On Si(100) oriented surfaces, crystalline Pr2O3 grows as (110)-domains, with two orthogonal in-plane orientations. Epitaxial overgrowth with Si could not been realized so far. We obtain perfect epitaxial growth of hexagonal Pr2O3 on Si(111). These layers can also be overgrown epitaxially with Si leading to novel tunnel structures. Crystalline Pr2O3 on Si(OOl) is a promising candidate for highly scaled gate insulators, displaying sufficiently high-K value of around 30, ultra-low leakage current density, good reliability, and high electrical breakdown voltage. The Pr2O3/Si(001) interface exhibits the symmetric band alignment, desired for applying such material in both n- and p-type devices. The valence band as well as the conduction band offset to Si is above 1 eV. The electron masses can be assumed to be very heavy in the oxide. This effect together with the suitable band offsets leads to the unusually low leakage currents found experimentally. Finally, the integration of crystalline Pr2O3 high-K gate dielectrics into a conventional CMOS process will be demonstrated.
The relationship between the defect microstructure of SiC films grown by solid-source molecular-beam epitaxy on 4H and 6H–SiC substrates and their growth conditions, for substrate temperatures ranging between 950 and 1300 °C, has been investigated by a combination of transmission electron microscopy and atomic force microscopy. The results demonstrate that the formation of defective cubic films is generally found to occur at temperatures below 1000 °C. At temperatures above 1000 °C our investigations prove that simultaneous supply of C and Si in the step-flow growth mode on vicinal 4H and 6H substrate surfaces results in defect-free hexagonal SiC layers, and defect-free cubic SiC can be grown by the alternating deposition technique. The controlled overgrowth of hexagonal on top of cubic layers is demonstrated for thin layer thicknesses.