457 research outputs found
First-Order Concatenation Theory with Bounded Quantifiers
We study first-order concatenation theory with bounded quantifiers. We give
axiomatizations with interesting properties, and we prove some normal-form
results. Finally, we prove a number of decidability and undecidability results.Comment: arXiv admin note: text overlap with arXiv:1804.0636
A Friendly Introduction to Mathematical Logic
At the intersection of mathematics, computer science, and philosophy, mathematical logic examines the power and limitations of formal mathematical thinking. In this expansion of Leary’s user-friendly 1st edition, readers with no previous study in the field are introduced to the basics of model theory, proof theory, and computability theory. The text is designed to be used either in an upper division undergraduate classroom, or for self study. Updating the 1st Edition’s treatment of languages, structures, and deductions, leading to rigorous proofs of Gödel’s First and Second Incompleteness Theorems, the expanded 2nd Edition includes a new introduction to incompleteness through computability as well as solutions to selected exercises. Available on Lulu.com, IndiBound.com, and Amazon.com, as well as wholesale through Ingram Content Group.https://knightscholar.geneseo.edu/geneseo-authors/1005/thumbnail.jp
Glycine and hyperammonemia : potential target for the treatment of hepatic encephalopathy
Hepatic encephalopathy (HE) is a neuropsychiatric
disorder caused by hepatic dysfunction. Numerous studies
dictate that ammonia plays an important role in the pathogenesis of HE, and hyperammonemia can lead to alterations in
amino acid homeostasis. Glutamine and glycine are both
ammoniagenic amino acids that are increased in liver failure.
Modulating the levels of glutamine and glycine has shown to
reduce ammonia concentration in hyperammonemia.
Ornithine Phenylacetate (OP) has consistently been shown to
reduce arterial ammonia levels in liver failure by modulating
glutamine levels. In addition to this, OP has also been found to
modulate glycine concentration providing an additional ammonia removing effect. Data support that glycine also serves
an important role in N-methyl D-aspartate (NMDA) receptor
mediated neurotransmission in HE. This potential important
role for glycine in the pathogenesis of HE merits further
investigations
Reproductive strategy and singing activity: blue tit and great tit compared
The costs and benefits of bird song are likely to vary among species, and different singing patterns may reflect differences in reproductive strategies. We compared temporal patterns of singing activity in two songbird species, the blue tit (Cyanistes caeruleus) and the great tit (Parus major). The two species live side by side year round, and they have similar breeding ecology and similar rates of extra-pair paternity. However, they differ in two aspects of reproductive strategy that may have an influence on song output: blue tits are facultatively polygynous and have a fairly short breeding season with almost no second broods, whereas great tits are socially monogamous but more commonly raise second broods. We found that great tit males continued singing at high levels during the egg-laying and incubation periods, while monogamously paired blue tit males strongly reduced singing activity after the first days of egg-laying by their female. Since males of both species sang much more intensely shortly before sunrise than after sunrise, at midday or in the evening, this difference was most conspicuous at dawn. No differences in singing activity were found within species when testing for male age. We suggest that in contrast to blue tits, great tit males continued singing after egg-laying to defend the territory and to encourage the female for a possible second broo
PCIe Device Lending
We have developed a proof of concept for allowing a PCI Express device attached to one computer to be used by another computer without any software intermediate on the data path. The device driver runs on a physically separate machine from the device, but our implementation allows the device driver and device to communicate as if the device and driver were in the same machine, without modifying either the driver or the device. The kernel and higher level software can utilize the device as if it were a local device. A device will not be used by two separate machines at the same time, but a machine can transfer the control of a local device to a remote machine. We have named this concept "device lending". We envision that machines will have, in addition to local PCIe devices, access to a pool of remote PCIe devices. When a machine needs more device resources, additional devices can be dynamically borrowed from other machines with devices to spare. These devices can be located in a dedicated external cabinet, or be devices inserted into internal slots in a normal computer. The device lending is implemented using a Non-Transparent Bridge (NTB), a native PCIe interconnect that should offer performance close to that of a locally connected device. Devices that are not currently being lent to another host will not be affected in any way. NTBs are available as add-ons for any PCIe based computer and are included in newer Intel Xeon CPUs. The proof of concept we created was implemented for Linux, on top of the APIs provided by our NTB vendor, Dolphin. The host borrowing a device has a kernel module to provide the necessary software support and the other host has a user space daemon. No additional software modifications or hardware is required, nor special support from the devices. The current implementation works with some devices, but has some problems with others. We believe however, that we have identified the problems and how to improve the situation. In a later implementation, we believe that all devices we have tested can be made to work correctly and with very high performance
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