10,426 research outputs found
Sertraline and Phenytoin Drug Interaction in a Geriatric Patient
This report presents the case of a 78-year-old man residing in a nursing home who presented with a 2-month history of increasing lethargy and confusion. These symptoms coincided with the initiation of sertraline in the patient. Among other medications, he was also taking phenytoin. The medical team concluded that the cause of the patientâs lethargy and confusion was a drug interaction between sertraline and phenytoin. Phenytoin was held, while the sertraline was slowly tapered to discontinuation. The patientâs symptoms resolved soon thereafter. Future research is needed to better guide clinicians in appropriate selection, dosing, and monitoring of selective serotonin reuptake inhibitors with concomitant phenytoin use.Key words: phenytoin, sertraline, SSRIs, drug interactio
Equivariant differential characters and symplectic reduction
We describe equivariant differential characters (classifying equivariant
circle bundles with connections), their prequantization, and reduction
Non-Gaussian velocity distributions in excited granular matter in the absence of clustering
The velocity distribution of spheres rolling on a slightly tilted rectangular
two dimensional surface is obtained by high speed imaging. The particles are
excited by periodic forcing of one of the side walls. Our data suggests that
strongly non-Gaussian velocity distributions can occur in dilute granular
materials even in the absence of significant density correlations or
clustering. When the surface on which the particles roll is tilted further to
introduce stronger gravitation, the collision frequency with the driving wall
increases and the velocity component distributions approach Gaussian
distributions of different widths.Comment: 4 pages, 5 figures. Additional information at
http://physics.clarku.edu/~akudrolli/nls.htm
Polymers pushing Polymers: Polymer Mixtures in Thermodynamic Equilibrium with a Pore
We investigate polymer partitioning from polymer mixtures into nanometer size
cavities by formulating an equation of state for a binary polymer mixture
assuming that only one (smaller) of the two polymer components can penetrate
the cavity. Deriving the partitioning equilibrium equations and solving them
numerically allows us to introduce the concept of "polymers-pushing-polymers"
for the action of non-penetrating polymers on the partitioning of the
penetrating polymers. Polymer partitioning into a pore even within a very
simple model of a binary polymer mixture is shown to depend in a complicated
way on the composition of the polymer mixture and/or the pore-penetration
penalty. This can lead to enhanced as well as diminished partitioning, due to
two separate energy scales that we analyse in detail.Comment: 10 pages, 6 figure
The XMM-Newton Wide field survey in the COSMOS field: redshift evolution of AGN bias and subdominant role of mergers in triggering moderate luminosity AGN at redshift up to 2.2
We present a study of the redshift evolution of the projected correlation
function of 593 X-ray selected AGN with I_AB<23 and spectroscopic redshifts
z<4, extracted from the 0.5-2 keV X-ray mosaic of the 2.13 deg^2 XMM-COSMOS
survey. We introduce a method to estimate the average bias of the AGN sample
and the mass of AGN hosting halos, solving the sample variance using the halo
model and taking into account the growth of the structure over time. We find
evidence of a redshift evolution of the bias factor for the total population of
XMM-COSMOS AGN from b(z=0.92)=2.30 +/- 0.11 to b(z=1.94)=4.37 +/- 0.27 with an
average mass of the hosting DM halos logM [h^-1 M_sun] ~ 13.12 +/- 0.12 that
remains constant at all z < 2. Splitting our sample into broad optical lines
AGN (BL), AGN without broad optical lines (NL) and X-ray unobscured and
obscured AGN, we observe an increase of the bias with redshift in the range
z=0.7-2.25 and z=0.6-1.5 which corresponds to a constant halo mass logM [h^-1
M_sun] ~ 13.28 +/- 0.07 and logM [h^-1 M_sun] ~ 13.00 +/- 0.06 for BL /X-ray
unobscured AGN and NL/X-ray obscured AGN, respectively. The theoretical models
which assume a quasar phase triggered by major mergers can not reproduce the
high bias factors and DM halo masses found for X-ray selected BL AGN with L_BOL
~ 2e45 erg s^-1. Our work extends up to z ~ 2.2 the z <= 1 statement that, for
moderate luminosity X-ray selected BL AGN, the contribution from major mergers
is outnumbered by other processes, possibly secular such as tidal disruptions
or disk instabilities.Comment: 16 emulateapj pages, 18 figures and 3 tables. Accepted for the
publication in The Astrophysical Journa
Testing Convolutional Neural Networks for finding strong gravitational lenses in KiDS
Convolutional Neural Networks (ConvNets) are one of the most promising
methods for identifying strong gravitational lens candidates in survey data. We
present two ConvNet lens-finders which we have trained with a dataset composed
of real galaxies from the Kilo Degree Survey (KiDS) and simulated lensed
sources. One ConvNet is trained with single \textit{r}-band galaxy images,
hence basing the classification mostly on the morphology. While the other
ConvNet is trained on \textit{g-r-i} composite images, relying mostly on
colours and morphology. We have tested the ConvNet lens-finders on a sample of
21789 Luminous Red Galaxies (LRGs) selected from KiDS and we have analyzed and
compared the results with our previous ConvNet lens-finder on the same sample.
The new lens-finders achieve a higher accuracy and completeness in identifying
gravitational lens candidates, especially the single-band ConvNet. Our analysis
indicates that this is mainly due to improved simulations of the lensed
sources. In particular, the single-band ConvNet can select a sample of lens
candidates with purity, retrieving 3 out of 4 of the confirmed
gravitational lenses in the LRG sample. With this particular setup and limited
human intervention, it will be possible to retrieve, in future surveys such as
Euclid, a sample of lenses exceeding in size the total number of currently
known gravitational lenses.Comment: 16 pages, 10 figures. Accepted for publication in MNRA
Reusable Agena study. Volume 2: Technical
The application of the existing Agena vehicle as a reusable upper stage for the space shuttle is discussed. The primary objective of the study is to define those changes to the Agena required for it to function in the reusable mode in the 100 percent capture of the NASA-DOD mission model. This 100 percent capture is achieved without use of kick motors or stages by simply increasing the Agena propellant load by using optional strap-on-tanks. The required shuttle support equipment, launch and flight operations techniques, development program, and cost package are also defined
Two Late Quaternary Pollen Records from South-Central Alaska
Pollen records from Wonder and Ten Mile lakes, located at aititudinal treeline to the north and south of the Alaska Range respectively, document the vegetation history of a portion of the southern Alaskan boreal forest. The new pollen diagrams indicate a Betula shrub tundra, preceded at Wonder Lake by a sparse herb tundra, which characterized these two areas during latest Wisconsinan times. Populus was in the vicinity of Ten Mile Lake ca. 10,000 BP, but was apparently absent from Wonder Lake. Picea glauca grew at or near Ten Mile Lake by 9100 BP, with P. mariana becoming important ca. 7000 BP. The first forests at Wonder Lake were also dominated by P. glauca and followed by increased numbers of P. mariana. The timing of forest establishment at Wonder Lake is uncertain due to problematic radiocarbon dates. Alnus appears to be common in both regions by ca. 7000 BP. These records suggest that paleo-vegetational reconstructions are more difficult for the southern than northern boreal forests in Alaska because of greater topographic diversity, difficulties with over-representation of some pollen taxa, and problems with radiocarbon dating. Despite these concerns, available data from south-central Alaska suggest that southern and northern forests differ in their vegetational histories. Such differences, when related to temperature fluctuations that have been postulated for the Holocene, imply that the Alaskan boreal forest may not respond uniformly to future global warming.Les inventaires polliniques de Wonder Lake et de Ten Mile Lake, situĂ©s Ă la limite altitudinale des arbres au nord et au sud de la chaĂźne de l'Alaska permettent de reconstituer l'histoire de la vĂ©gĂ©tation d'une portion de la forĂȘt borĂ©ale du sud de l'Alaska. Les nouveaux diagrammes polliniques montrent une toundra arbustive Ă Betula, prĂ©cĂ©dĂ©e au Wonder Lake par une toundra herbacĂ©e clairsemĂ©e, Ă la fin du Wisconsinien. Vers 10 000 BP, Populus Ă©tait dans les environs du Ten Mile Lake, mais Ă©tait apparamment absent du Wonder Lake. Picea glauca croissait autour du Ten Mile Lake Ă 9100 BP et P. mariana prenait de l'importance vers 7000 BP. Au Wonder Lake, les premiĂšres forĂȘts ont Ă©galement Ă©tĂ© dominĂ©es par P. glauca, puis par un nombre croissant de P. mariana. La chronologie de !'afforestation est incertaine en raison de datations au radiocarbone douteuses. Alnus semble ĂȘtre une espĂšce courante dans les deux rĂ©gions vers 7000 BP. Les inventaires indiquent que la reconstitution de la palĂ©ovĂ©gĂ©tation est plus difficile Ă faire pour les forĂȘts mĂ©ridionales que septentrionales de l'Alaska, en raison de la plus grande diversitĂ© topographique, la sur-reprĂ©sentation de certains taxons et des problĂšmes de radio-datation. Les donnĂ©es indiquent tout de mĂȘme que l'histoire de la vĂ©gĂ©tation des forĂȘts diffĂšrent au nord et au sud. Ces diffĂ©rences, mises en relation avec les fluctuations de tempĂ©ratures prĂ©sumĂ©es de l'HolocĂšne, laissent croire que la forĂȘt de l'Alaska ne rĂ©pondra pas nĂ©cessairement de façon uniforme Ă un rĂ©chauffement climatique Ă©ventuel.DbiJibneBbie aiiarpa.viMbi ocaaKOB 03ep Baeae n TeHMaRJi, pacnojioxeHiibix B6JIII3H Bepxiiert rpaiiMUbi Jieca Ha ceBepe H wre A/iflCKiiHCKoro xpeĂŽĂźa, OTpaacaioT ncropnio pacTHTejibHOCTH KOKIIOH lacr" Sopea/ibHoro jieca AJIBCKH. HoBbie ribiJibuebe anarpaMMbi iiOKaabiBaioT, HTO KycTapmiKOBOfi 6epr30B0fi TyHApe, xapaKTepiioft aJifl 3TMX aByx TeppiiTopufl B Teieime no3iuiero BiicKoiicmia, npemuecTBOBajia B oTaoaceiinnx 03. Banae 6emiaH TpaBHHUCTHa iyHapa. Populus iipopn3parra.n B otcpecruocnix 03. Teii.vianji 10000 /J.H., HO, JlO-BIUHMOMy, OTCyTCTBOBaa B pafione 03. BaHae. 9100 JI.H. B panoHe 03. Tenvianj] H.11I B iienocpeacrBeimoH 6/IH30CTH OT iiero npoH3pacTajia Picea glauca, KOTopan BMepTe c Picea mariana nrpaeT 3Ha'iiiTe/ibnyio pojib B codaBe pacTHTeJibHOCTM OKO/IO 7000 .i.n. B nepBbix Jiecax B paflone 03. BaHae TaKjKe aoMiiiuipoBajia Picea glauca, 110 3aTe,vi pojib Picea mariana iiaHimaeT B03pacacTaTb. Bpe.viH noflB/ieiiHfl jiecoB B panone 03. Banae uoKaiie ycraiiaBJiiiBaeTca iiaaeacHo paaiioyr-jiepoaiibiM McroaoM. Alnus o6pa3yer cooBiuecTBa B06011X pafioiiax OKOJIO 7000 JI.H. nojiyieiuibie aaiiHbie cBiiaeTejibCTByioT 0 TOM, HTO peKoiicTpyKniifl pacTiiTejibiiocTH 6yaer 6ojieecjio>KHon aJin lOĂźKHbix, ieM aJifl ceaepiibix 6opeajibiibix JiecoB AJIHCKH 1133a SHa'iinejibiioro TonorpafpimecKoro iiecxoacTBa,3aTpyaiieiii!Ji B iiHTepnpeTaumi neKOTopwx nbijibneitbix TaKCOHOB, npoGjieM c paanoyrjiepoaiibiM aaTHpBaiine.M. HeavioTpa tia 3TH npo6jieivibi, nojicpieHHbie aaHiibie noKa3biaiOT, HTO fjopeajibiibie Jieca 11a wre 11 ceBepe ioaciion iacni UetiTajibiion AJIHCKH wweioT pa3Jiiiiyio iiCTopnio. TaKiie pa3Jinmtfl, cBfl3xaiuibie c n3MeiieiijiflMii 3eMJiepaTyp B Teieiuie ro.'ioueiia, cBiiae-Te.TbCTByioT, HTO 6opeajibiibiri Jiec AJIHCKH ,vioxer ne OTBenaTb cienapnio rjio6aJibiioro noTen.ieiina u SyaymeM
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