Technology and Textile Mill Architecture in Canada

Textile mills evolved as a distinct architectural type in the late eighteenth and early nineteenth centuries. To a large extent their long, narrow, high form was determined by the needs to distribute power by mechanical means from a central source and to provide good lighting for spinning and weaving. Mills were susceptible to fire. To reduce the risk of fire British mill engineers developed the fireproof mill design in which flammable materials were replaced with cast iron and brick wherever possible. American engineers developed the slow-burning mill design in which heavy-timber construction, isolation of potential fires and efficient fire-fighting systems were designed to slow the spread of fire and allow effective fire fighting. When Canada's textile industry began to expand in the 1870s it adopted the slow-burning method of construction. By the early twentieth century changes in power transmission systems and lighting systems had made the old mill form obsolete. New building materials had made both slow-burning and fireproof mill construction obsolete. However, economic conditions limited new building programs and many of the old mills remained in use until the second half of the twentieth century. Résumé Les filatures ont donné naissance à un type d'architecture distinct à la fin du XVIIIe et au début du XIXe siècle. La forme de ces hauts bâtiments étroits et longs était déterminée par la nécessité d'y distribuer la force motrice par des moyens mécaniques à partir d'une source centrale et d'assurer un bon éclairage pour le filage et le tissage. Les risques d'incendie qui menaçaient constamment les filatures britanniques ame-nèrent les ingénieurs chargés d'en concevoir les plans à développer un modèle de filature à l'épreuve du feu, en remplaçant les matériaux inflammables par de la fonte et de la brique partout où cela était possible. Dans le même esprit, les ingénieurs américains mirent au point un modèle de filature aux matériaux peu combustibles à propos duquel l'ossature en gros madriers, l'isolation des sources possibles d'incendies et des systèmes efficaces pour les combattre concouraient à ralentir la propagation du feu et à faciliter le travail des pompiers. Quand l'industrie textile prit son essor au Canada dans les années 1870, on adopta la méthode des matériaux peu combustibles pour la construction des filatures. Au début du XXe siècle, avec l'évolution des systèmes d'éclairage et de transmission de l'énergie, l'ancienne architecture des filatures n'avait plus sa raison d'être. L'utilisation de nouveaux matériaux de construction rendait le modèle de filature à l'épreuve du feu et le modèle aux matériaux peu combustibles complètement dépassés. Mais la situation économique ne se prêtait guère à l'érection de nouveaux bâtiments et beaucoup des an-ciennes filatures sont restées en service jusqu 'à la seconde moitié du XXe siècle

The intellectual and moral integrity of bioethics: response to commentaries on A case study in unethical transgressive bioethics: \u27Letter of concern from bioethicists\u27 about the prenatal administration of dexamethasone .

In our target article we showed that the Letter of Concern (LoC) fails to meet accepted standards for presenting empirical data for the purpose of supplementing a normative claim and for argument-based normative ethics. The LoC fails to meet the standards of evidence-based reasoning by making false claims, failing to reference data that undermine its key premises, and misrepresenting and misinterpreting the scientific publications it selectively references. The LoC fails to meet the standards of argument-based reasoning by treating as settled matters what are, instead, ongoing controversies, offering “mere opinion” as a substitute for argument, and making contradictory claims. The LoC is methodologically defective and thus a case study in unethical transgressive bioethics. Not withdrawing the LoC will damage the field of bioethics, making this case study in unethical transgressive bioethics important for the entire field

The Multitude of Molecular Hydrogen Knots in the Helix Nebula

We present HST/NICMOS imaging of the H_2 2.12 \mu m emission in 5 fields in the Helix Nebula ranging in radial distance from 250-450" from the central star. The images reveal arcuate structures with their apexes pointing towards the central star. Comparison of these images with comparable resolution ground based images reveals that the molecular gas is more highly clumped than the ionized gas line tracers. From our images, we determine an average number density of knots in the molecular gas ranging from 162 knots/arcmin^2 in the denser regions to 18 knots/arcmin^2 in the lower density outer regions. Using this new number density, we estimate that the total number of knots in the Helix to be ~23,000 which is a factor of 6.5 larger than previous estimates. The total neutral gas mass in the Helix is 0.35 M_\odot assuming a mass of \~1.5x10^{-5} M_\odot for the individual knots. The H_2 intensity, 5-9x10^{-5} erg s^{-1} cm^{-2} sr^{-1}, remains relatively constant with projected distance from the central star suggesting a heating mechanism for the molecular gas that is distributed almost uniformly in the knots throughout the nebula. The temperature and H_2 2.12 \mu m intensity of the knots can be approximately explained by photodissociation regions (PDRs) in the individual knots; however, theoretical PDR models of PN under-predict the intensities of some knots by a factor of 10.Comment: 26 pages, 3 tables, 10 figures; AJ accepte

Professionally responsible counseling when a fetal anomaly is diagnosed by ultrasound

© The Author(s). 2020. Ethics plays an essential role in the clinical management of pregnancies complicated by fetal anomalies diagnosed by ultrasound. Utilizing the prima facie ethical principles of beneficence and respect for autonomy, this paper first explicates the ethical concept of the fetus as a patient. This ethical concept provides the basis for a comprehensive approach to counseling pregnant women about the management of pregnancies complicated by fetal anomalies. Practical, ethically justified guidance is given for counseling about decisions both before and after viabilities

Teaching Professional Formation in Response to the COVID-19 Pandemic.

In response to the COVID-19 pandemic, the Association of American Medical Colleges has called for a temporary suspension of clinical teaching activities for medical students. Planning for the continued involvement of learners in patient care during this pandemic should include teaching learners professional formation. The authors provide an ethical framework to guide such teaching, based on the ethical principle of beneficence and the professional virtues of courage and self-sacrifice from professional ethics in medicine. The authors show that these concepts support the conclusion that learners are ethically obligated to accept reasonable, but not unreasonable, risk. Based on this ethical framework, the authors provide an account of the process of teaching professional formation that medical educators and academic leaders should implement. Medical educators and academic leaders should embrace the opportunity that the COVID-19 pandemic presents for teaching professional formation. Learners should acquire the conceptual vocabulary of professional formation. Learners should recognize that risk of infection from patients is unavoidable. Learners should become aware of established ethical standards for professional responsibility during epidemics from the history of medicine. Learners should master understandable fear. Medical educators and academic leaders should ensure that didactic teaching of professional formation continues when it becomes justified to end learners\u27 participation in the processes of patient care; topics should include the professionally responsible management of scarce medical resources. The COVID-19 pandemic will not be the last major infectious disease that puts learners at risk. Professional ethics in medicine provides powerful conceptual tools that can be used as an ethical framework to guide medical educators to teach learners, who will bear leadership responsibilities in responses to future pandemics, professional formation