1,526 research outputs found
History of Water-Hammer
No full textWater-hammer is the phenomenon of the transmission of pressure and velocity surges along a pipe or conduit when a change in either the velocity or the pressure is imposed at some section in the pipe or at its ends. This change maybe imposed by some mechanical device such as a valve or by a variation in the performance of some hydraulic machinery attached to the pipe, such as a pump or hydraulic turbine. This report traces the theoretical development of the phenomenon of water-hammer from the days of the natural scientists of the seventeenth century to the middle of the twentieth century. In the larger field of hydraulics, early development was based on problems of transportation of water, and on the measurement of flow for irrigation and for domestic use in the centres of population. This involved devices for pumping, for delivery along canals and conduits, and for the measurement of quantities used by individuals. The theory and designs had to do with hydrostatic pressures, friction losses, and discharge coefficients, most of which could be handled by experimental studies. There was no need to consider cases of unsteady flow, either in open channels or in closed pipes and conduits. The action of waves on shore lines, in bays and ports, and along canals, was the only problem similar to water-hammer known in early times, and the mathematical and physical knowledge in those days was unable to cope with this problem except by construction of breakwaters for protection of harbours and shipping. This branch of hydraulics, now designated as coastal engineering, which deals with tidal and surface waves, has become a very important field, particularly in this 20th century
Keynote Address: The Biographical Container
No full textKeynote address: “The Biographical Container” by Langdon Hammer, author of James Merrill: Life and Art (Knopf). Watch the video of the address here: https://www.youtube.com/watch?v=BquCAmR6ANI
Henri Temianka Correspondence; (hammer)
No full textThis collection contains material pertaining to the life, career, and activities of Henri Temianka, violin virtuoso, conductor, music teacher, and author. Materials include correspondence, concert programs and flyers, music scores, photographs, and books.https://digitalcommons.chapman.edu/temianka_correspondence/3745/thumbnail.jp
Homodimerization and isoform-specific heterodimerization of neuroligins
No full textNeuroligins are postsynaptic adhesion proteins involved in the establishment of functional synapses in the central nervous system. In rodents, four genes give rise to neuroligins that function at distinct synapses, with corresponding neurotransmitter and subtype specificities. In the present study, we examined the interactions between the different neuroligins by isolating endogenous oligomeric complexes using in situ cross-linking on primary neurons. Examining hippocampal, striatal, cerebellar and spinal cord cultures, we found that neuroligins form constitutive dimers, including homomers and, most notably, neuroligin 1/3 heteromers. Additionally, we found that neuroligin monomers are specifically retained in the secretory pathway through a cellular quality control mechanism that involves the neuroligin transmembrane domain, ensuring that dimerization occurs prior to cell surface trafficking. Lastly, we identified differences in the dimerization capacity of autism-associated neuroligin mutants, and found that neuroligin 3 R471C mutants can form heterodimers with neuroligin 1. The pervasive nature of neuroligin dimerization indicates that the unit of neuroligin function is the dimer, and raises intriguing possibilities of distinct heterodimer functions, and of interactions between native and mutant neuroligins contributing to disease phenotypes
Artificial intelligence: applications in the field of medicine where it currently outperforms human capabilities
No full textAuthor Samuel Hammer, BSc.Angefertigt am Krankenhaus der Elisabethinen / Ordensklinikum; Abteilung für Hämatologie und OnkologieMasterarbeit Johannes Kepler Universität Linz 2025Arbeit auf den öffentlichen PCs in den Bibliotheken der JKU+Medizin abrufba
Artificial intelligence: applications in the field of medicine where it currently outperforms human capabilities
No full textAuthor Samuel Hammer, BSc.Angefertigt am Krankenhaus der Elisabethinen / Ordensklinikum; Abteilung für Hämatologie und OnkologieMasterarbeit Johannes Kepler Universität Linz 2025Arbeit auf den öffentlichen PCs in den Bibliotheken der JKU+Medizin abrufba
History of the Ottoman Turks: from the beginning of their Empire to the present time : Chiefly founded on von Hammer / By E. S. Creasy, M. A. ... Author of "The fifteen Decisive Battles of the World" ...
No full text- …
