86 research outputs found
Ternary algebras and groups
We construct explicitly groups associated to specific ternary algebras which
extend the Lie (super)algebras (called Lie algebras of order three). It turns
out that the natural variables which appear in this construction are variables
which generate the three-exterior algebra. An explicit matrix representation of
a group associated to a peculiar Lie algebra of order three is constructed
considering matrices with entry which belong to the three exterior algebra.Comment: 11 pages contribution to the 5th International Symposium on Quantum
Theory and Symmetries (QTS5
Tensor analyzing power Ayy in deuteron inclusive breakup at large Pt and spin structure of deuteron at short internucleonic distances
The Ayy data for deuteron inclusive breakup off hydrogen and carbon at a
deuteron momentum of 9.0 GeV/c and large Pt of emitted protons are presented.
The large values of Ayy independent of the target mass reflect the sensitivity
of the data to the deuteron spin structure. The data obtained at fixed and
plotted versus Pt clearly demonstrate the dependence of the deuteron spin
structure at short internucleonic distances on two variables. The data are
compared with the calculations using Paris, CD-Bonn and Karmanov's deuteron
wave functions.Comment: 4 pages, 2 figures, talk given at the SPIN2004 Conf., 10-16 Oct.
2004, Triest, Ital
Tensor Ayy and vector Ay analyzing powers in the H(d,d')X and ^{12}C(d,d')X reactons at initial deuteron momenta of 9 GeV/c in the region of baryonic resonances excitation
The angular dependence of the tensor Ayy and vector Ay analyzing powers in
the inelastic scattering of deuterons with a momentum of 9.0 GeV/c on hydrogen
and carbon have been measured. The range of measurements corresponds to the
baryonic resonance excitation with masses 2.2--2.6 GeV/c^2. The Ayy data being
in good agreement with the previous results demonstrate an approximate
scaling up to -1.5 (GeV/c)^2. The large values of A_y show a significant role
of the spin-dependent part of the elementary amplitude of the NN->NN* reaction.
The results of the experiment are compared with model predictions of the
plane-wave impulse approximation.Comment: 7 pages, 7 figures. submitted to Yad.Fi
Nonlocal interactions prevent collapse in negative scattering length Bose-Einstein gases
We study the effect of nonlocality on the collapse properties of a
self-focusing Nonlinear Schr\"odinger system related to Bose-Einstein
condensation problems.
Using a combination of moment techniques, time dependent variational methods
and numerical simulations we present evidences in support of the hypothesis
that nonlocal attractively interacting condensates cannot collapse when the
dominant interaction term is due to finite range interactions. Instead there
apppear oscillations of the wave packet with a localized component whose size
is of the order of the range of interactions.
We discuss the implications of the results to collapse phenomena in negative
scattering length Bose-Einstein condensates
Hall effect in the vicinity of quantum critical point in Tm1-xYbxB12
The angular, temperature and magnetic field dependences of Hall resistance
roH for the rare-earth dodecaboride solid solutions Tm1-xYbxB12 have been
studied in a wide vicinity of the quantum critical point (QCP) xC~0.3. The
measurements performed in the temperature range 1.9-300 K on high quality
single crystals allowed to find out for the first time in these fcc compounds
both an appearance of the second harmonic contribution in ro2H at QCP and its
enhancement under the Tm to ytterbium substitution and/or with increase of
external magnetic field. When the Yb concentration x increases a negative
maximum of a significant amplitude was shown to appear on the temperature
dependences of Hall coefficient RH(T) for the Tm1-xYbxB12 compounds. Moreover,
a complicated activation type behavior of the Hall coefficient is observed at
intermediate temperatures for x>0.5 with activation energies Eg~200K and
Ea~55-75K in combination with the sign inversion of RH(T) at low temperatures
in the coherent regime. The density of states renormalization effects are
analyzed within the variation of Yb concentration and the features of the
charge transport in various regimes (charge gap formation, intra-gap manybody
resonance and coherent regime) are discussed in detail in Tm1-xYbxB12 solid
solutions.Comment: 38 pages including 10 figures, 70 reference
Toksikokinetika prometrina u mozgu miševa
Prometryne is a methylthio-s-triazine herbicide. Signifi cant trace amounts are found in the environment,
mainly in water, soil, and food plants. The aim of this study was to establish brain and blood prometryne levels after single oral dose (1 g kg-1) in adult male and female mice. Prometryne was measured using the GC/MS assay at 1, 2, 4, 8, and 24 h after prometryne administration. Peak brain and blood prometryne values were observed 1 h after administration and they decreased in a time-dependent manner. Male mice had consistently higher brain and blood prometryne levels than female mice. The observed prometryne
kinetics was similar to that reported for the structurally related herbicide atrazine.Prometrin je metiltio-s-triazinski herbicid. Značajne količine prometrina zaostaju u tragovima u okolišu, poglavito u vodi, tlu i biljkama koje rabimo za prehranu. Cilj je rada izmjeriti količinu prometrina koja se apsorbira u mozgu i krvi nakon primijenjene akutne oralne doze (1 g kg-1 tjelesne mase) u odraslih miševa
obaju spolova. Razine prometrina u mozgu i krvi izmjerene su GC/MS-om tijekom 1., 2., 4., 8. i 24. sata nakon izlaganja. Utvrđeno je da je udio prometrina koji se zadržava u živčanom tkivu relativno nizak ali detektabilan u odnosu na koncentraciju u krvi i koncentraciju primijenjene doze. Najviše koncentracije u krvi i maseni udjeli u mozgu zabilježeni su tijekom 1. sata nakon izlaganja, a s vremenom izmjerene vrijednosti značajno opadaju. Uočena je značajna razlika između mužjaka i ženki pri čemu mužjaci imaju
značajno više razine prometrina u mozgu i krvi nego ženke. Opisana toksikokinetika prometrina pokazuje sličnosti s otprije opisanom i poznatom toksikokinetikom strukturalno sličnog herbicida atrazina
Intravenous alteplase for stroke with unknown time of onset guided by advanced imaging: systematic review and meta-analysis of individual patient data
Background: Patients who have had a stroke with unknown time of onset have been previously excluded from thrombolysis. We aimed to establish whether intravenous alteplase is safe and effective in such patients when salvageable tissue has been identified with imaging biomarkers. Methods: We did a systematic review and meta-analysis of individual patient data for trials published before Sept 21, 2020. Randomised trials of intravenous alteplase versus standard of care or placebo in adults with stroke with unknown time of onset with perfusion-diffusion MRI, perfusion CT, or MRI with diffusion weighted imaging-fluid attenuated inversion recovery (DWI-FLAIR) mismatch were eligible. The primary outcome was favourable functional outcome (score of 0–1 on the modified Rankin Scale [mRS]) at 90 days indicating no disability using an unconditional mixed-effect logistic-regression model fitted to estimate the treatment effect. Secondary outcomes were mRS shift towards a better functional outcome and independent outcome (mRS 0–2) at 90 days. Safety outcomes included death, severe disability or death (mRS score 4–6), and symptomatic intracranial haemorrhage. This study is registered with PROSPERO, CRD42020166903. Findings: Of 249 identified abstracts, four trials met our eligibility criteria for inclusion: WAKE-UP, EXTEND, THAWS, and ECASS-4. The four trials provided individual patient data for 843 individuals, of whom 429 (51%) were assigned to alteplase and 414 (49%) to placebo or standard care. A favourable outcome occurred in 199 (47%) of 420 patients with alteplase and in 160 (39%) of 409 patients among controls (adjusted odds ratio [OR] 1·49 [95% CI 1·10–2·03]; p=0·011), with low heterogeneity across studies (I2=27%). Alteplase was associated with a significant shift towards better functional outcome (adjusted common OR 1·38 [95% CI 1·05–1·80]; p=0·019), and a higher odds of independent outcome (adjusted OR 1·50 [1·06–2·12]; p=0·022). In the alteplase group, 90 (21%) patients were severely disabled or died (mRS score 4–6), compared with 102 (25%) patients in the control group (adjusted OR 0·76 [0·52–1·11]; p=0·15). 27 (6%) patients died in the alteplase group and 14 (3%) patients died among controls (adjusted OR 2·06 [1·03–4·09]; p=0·040). The prevalence of symptomatic intracranial haemorrhage was higher in the alteplase group than among controls (11 [3%] vs two [<1%], adjusted OR 5·58 [1·22–25·50]; p=0·024). Interpretation: In patients who have had a stroke with unknown time of onset with a DWI-FLAIR or perfusion mismatch, intravenous alteplase resulted in better functional outcome at 90 days than placebo or standard care. A net benefit was observed for all functional outcomes despite an increased risk of symptomatic intracranial haemorrhage. Although there were more deaths with alteplase than placebo, there were fewer cases of severe disability or death. Funding: None
Medicinal and ethnoveterinary remedies of hunters in Trinidad
BACKGROUND: Ethnomedicines are used by hunters for themselves and their hunting dogs in Trinidad. Plants are used for snakebites, scorpion stings, for injuries and mange of dogs and to facilitate hunting success. RESULTS: Plants used include Piper hispidum, Pithecelobium unguis-cati, Bauhinia excisa, Bauhinia cumanensis, Cecropia peltata, Aframomum melegueta, Aristolochia rugosa, Aristolochia trilobata, Jatropha curcas, Jatropha gossypifolia, Nicotiana tabacum, Vernonia scorpioides, Petiveria alliacea, Renealmia alpinia, Justicia secunda, Phyllanthus urinaria,Phyllanthus niruri,Momordica charantia, Xiphidium caeruleum, Ottonia ovata, Lepianthes peltata, Capsicum frutescens, Costus scaber, Dendropanax arboreus, Siparuma guianensis, Syngonium podophyllum, Monstera dubia, Solanum species, Eclipta prostrata, Spiranthes acaulis, Croton gossypifolius, Barleria lupulina, Cola nitida, Acrocomia ierensis (tentative ID). CONCLUSION: Plant use is based on odour, and plant morphological characteristics and is embedded in a complex cultural context based on indigenous Amerindian beliefs. It is suggested that the medicinal plants exerted a physiological action on the hunter or his dog. Some of the plants mentioned contain chemicals that may explain the ethnomedicinal and ethnoveterinary use. For instance some of the plants influence the immune system or are effective against internal and external parasites. Plant baths may contribute to the health and well being of the hunting dogs
Microwave properties of HTS films: measurements in millimeter wave range
A theoretical and experimental justification of an approach proposed and developed by us for surface impedance standard measurements of HTS films is presented. An analysis of the electromagnetic properties of quasi-optical dielectric resonators with conducting endplates, which provides a theoretical background for studies of HTS films in the millimeter wave range, is performed. With this technique, the highest-quality modes, namely whispering gallery modes, are excited in a dielectric cylindrical disc sandwiched between HTS films. Considerable enhancement of the sensitivity of surface resistance measurements in the millimeter wave range is demonstrated, which is important for the fundamental investigation of superconductor physics. It is also shown that the measured frequency shift in the resonator with the HTS endplates as a function of the temperature reveals a possibility for accurate evaluation of the field penetration depth in HTS films
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