SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "db:Swepub ;pers:(Ågren Hans)"

Sökning: db:Swepub > Ågren Hans

  • Resultat 11-20 av 952
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
11.
  • Arul Murugan, N., et al. (författare)
  • Unusual binding-site-specific photophysical properties of a benzothiazole-based optical probe in amyloid beta fibrils
  • 2018
  • Ingår i: Physical Chemistry, Chemical Physics - PCCP. - : The Royal Society of Chemistry. - 1463-9076 .- 1463-9084. ; 20:31, s. 20334-20339
  • Tidskriftsartikel (refereegranskat)abstract
    • Optical imaging of amyloid fibrils serves as a cost-effective route for the diagnosis of Alzheimer-like conformational diseases. However{,} the challenge here is to optimize the binding affinity and photophysical properties of the optical imaging agents in a way specific to certain types of amyloids. In a few occasions it is shown that novel optical imaging agents can be designed to bind to a particular type of amyloid fibril with larger binding affinity and specificity. There is also a recent report on photoluminescent polythiophenes which display photophysical properties that can be used to distinguish the variants or subtypes of amyloids (J. Rasmussen et al.{,} Proc. Natl. Acad. Sci. U. S. A.{,} 2017{,} 114(49){,} 13018–13023). Based on a multiscale modeling approach{,} here{,} we report on the complementary aspect that the photophysical properties of a benzothiazole based optical probe (referred to as BTA-3) can be specific to the binding sites in the same amyloid fibrils and we attribute this to its varying electronic structure in different sites. As reported experimentally from competitive binding assay studies for many amyloid staining molecules and tracers{,} we also show multiple binding sites in amyloid fibrils for this probe. In particular{,} BTA-3 displayed a red-shift in its low-frequency absorption band only in site-4{,} a surface site of amyloid fibrils when compared to the spectra in water solvent. In the remaining sites{,} it exhibited a less significant blue shift for the same absorption band.
  •  
12.
  •  
13.
  • Backlund, Lena, et al. (författare)
  • Identifying predictors for good lithium response - A retrospective analysis of 100 patients with bipolar disorder using a life-charting method.
  • 2009
  • Ingår i: European psychiatry : the journal of the Association of European Psychiatrists. - : Cambridge University Press (CUP). - 0924-9338. ; 24:3, s. 171-7
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: Our aim was to investigate bipolar patients in order to test the validity of various outcome measures and to identify prognostic predictors for pharmacological treatment. MATERIAL AND METHOD: One hundred patients were interviewed using a computerized life-charting program in a descriptive, retrospective analysis. The concept "Burden of illness" was defined as a combination of severity and duration of episodes. Response to treatment was defined as the difference in burden before and after treatment, a low burden during treatment, and freedom of episodes for at least 3 years after insertion of treatment. RESULTS: The absence of mixed episodes and a high initial burden predicted a good response measured as the difference in burden. If remission for 3 years or a low burden during lithium treatment was used, the absence of rapid cycling and of mixed episodes were the most important predictors. The severity of illness before treatment had no impact. DISCUSSION AND CONCLUSION: We suggest the use of absolute measures of severity during treatment as the most appropriate measure of the outcome. Furthermore, our data provide corroboration that treatment with lithium ameliorates the prognosis of the illness, but that mixed episodes and rapid cycling predict a poorer response to lithium.
  •  
14.
  • Baev, A., et al. (författare)
  • A quantum mechanical - Electrodynamical approach to nonlinear properties : Application to optical power limiting with platinum-organic compounds
  • 2007
  • Ingår i: Journal of nonlinear optical physics and materials. - 0218-8635. ; 16:2, s. 157-169
  • Tidskriftsartikel (refereegranskat)abstract
    • Light propagation in a medium is sensitively dependent on the shape and intensity of the optical pulse as well as on the electronic and vibrational structure of the basic molecular units. We review in this paper the results of systematic studies of this problem for isotropic media. Our theoretical approach - the quantum mechanical-electrodynamical (QMED) approach - is based on a quantum mechanical account of the many-level electron-nuclear medium coupled to a numerical solution of the density matrix and Maxwell's equations. This allows us to accommodate a variety of nonlinear effects which accomplish the propagation of strong light pulses. Particular attention is paid to the understanding of the role of coherent and sequential excitations of electron-nuclear degrees of freedom. The QMED combination of quantum chemistry with classical pulse propagation enables us to estimate the optical transmission from cross sections of multi-photon absorption processes and from considerations of propagation effects, saturation and pulse effects. Results of the theory suggest that in the nonlinear regime, it is often necessary to simultaneously account for coherent one-step and incoherent step-wise multi-photon absorption, as well as for off-resonant excitations even when resonance conditions prevail. The dynamic theory of nonlinear propagation of a few interacting intense light pulses is highlighted here in a study of the optical power limiting with platinum-organic molecular compounds. © World Scientific Publishing Company.
  •  
15.
  • Baev, A., et al. (författare)
  • Bi-directional description of amplified spontaneous emission induced by three-photon absorption
  • 2005
  • Ingår i: Journal of the Optical Society of America. B, Optical physics. - 0740-3224 .- 1520-8540. ; 22:2, s. 385-393
  • Tidskriftsartikel (refereegranskat)abstract
    •  A semiclassical dynamic theory of the nonlinear propagation of a few interacting intense light pulses is applied to study the nonlinear counterpropagation of amplified spontaneous emission (ASE) induced by three-photon absorption of short intense laser pulses in a chromophore solution. Several important results from the modeling are reached for the ASE process developing in the regime of strong saturation. Accounting for ASE in both forward and backward directions with respect to the pump pulse results in a smaller efficiency of nonlinear conversion for the forward ASE compared with the case in which forward emission is considered alone, something that results from the partial repump of the absorbed energy to the backward ASE component; the overall efficiency is nevertheless higher than for the forward emission considered alone. The efficiency of nonlinear conversion of the pump energy to the counterpropagating ASE pulses is strongly dependent on the concentration of active molecules so that a particular combination of concentration versus cell length optimizes the conversion coefficient. Under certain specified conditions, the ASE effect is found to be oscillatory; the origin of oscillations is dynamical competition between stimulated emission and off-resonant absorption. This result can be considered one of the possible explanations of the temporal fluctuations of the forward ASE pulse [Nature 415, 767 (2002)].
  •  
16.
  • Baev, A., et al. (författare)
  • Doppler interference in dissociative resonant photoemission
  • 2002
  • Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 66:2
  • Tidskriftsartikel (refereegranskat)abstract
    • Resonant photoemission involving dissociative core excited states has been the subject of a great number of experimental and theoretical investigations in recent time. The resonant decay of such dissociating systems has been shown to lead to semiatomic Auger electron emission spectra, with particular angular behavior. In the present paper a detailed theoretical analysis of dissociative resonant photoemission spectra of homonuclear diatomic molecules is presented. The theory addresses both fixed in space and randomly oriented homonuclear molecules and emphasizes the Doppler effect and the role of the interference between channels referring to the Doppler split atomic fragments. It is shown that peaks originating from decay in the atomic fragments can be asymmetric and structured due to the Doppler interference effect. The predicted strong non-Lorentzian behavior of the substructure on the top of the Doppler broadened atomiclike contribution is traced to the interplay between decay channels leading to gerade and ungerade final states. Simulations based on wave-packet theory are compared with experimental data for molecular oxygen. Our numerical simulations of the atomiclike resonance of fixed in space molecules show that the spectral profile is very sensitive to the shape of interatomic potentials of core excited and final states. It is shown that the Doppler effect in the decay spectra depends upon the symmetry of the core excited state.
  •  
17.
  • Baev, A., et al. (författare)
  • General theory for pulse propagation in two-photon active media
  • 2002
  • Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 117:13, s. 6214-6220
  • Tidskriftsartikel (refereegranskat)abstract
    • The propagation of laser pulses of different lengths in nonlinear media of organic absorbers is described starting out from a recently suggested dynamical theory for two-photon absorption (TPA) of molecules in solutions [J. Opt. Soc. Am. B 19, 937 (2002)]. The roles of saturation effects and pulse duration on the suppression of TPA are emphasized. The numerical simulations of the pulse propagation are performed for a two-photon active charge transfer molecule using molecular parameters obtained from first principle calculations.
  •  
18.
  • Baev, A., et al. (författare)
  • Geometrical information on core-excited states obtained from interference quenching of vibrational states in resonant x-ray photoemission
  • 2003
  • Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 67:2
  • Tidskriftsartikel (refereegranskat)abstract
    • An interference quenching of the m=1 final state vibrational line in the resonant Auger decay of N 1s-->pi(*) core-excited N-2 is observed and analyzed. The intensity ratio between the m=1 and m=0 vibrational levels of the X (2)Sigma(g)(+) final state shows a surprising nonmonotonic variation as a function of frequency detuning, going through a minimum with a complete suppression of m=1. We have developed a simple model which indicates a linear relation between the value of the detuning frequency for this minimum and the equilibrium bond distance of the core-excited state. This implies the possibility of determining the equilibrium bond distances for core-excited states to a high degree of accuracy. Simultaneously with the simple model we present a strict theory of the studied effect. This strict theory allows us to explore the accuracy of determining the bond length of the core-excited state from resonant Auger spectra. We obtain a weak influence of the core-hole lifetime on the determined bond length, whereas the number of intermediate vibrational states accounted for in the numerical simulations seems to be quite important.
  •  
19.
  • Baev, A., et al. (författare)
  • Light-matter interaction of strong laser pulses in the micro-, nano-, and picosecond regimes
  • 2007
  • Ingår i: Materials Research Society Symposium Proceedings. - 9781605604206 ; , s. 12-29
  • Konferensbidrag (refereegranskat)abstract
    • Light propagation in a medium is sensitively dependent on the shape and intensity of the optical pulse as well as on the electronic and vibrational structure of the basic molecular units. We review in this paper results of systematic studies of this problem for isotropic media. Our theoretical approach-the quantum mechanical-electrodynamical (QMED) approach-is based on a quantum mechanical account of the many-level electron-nuclear medium coupled to a numerical solution of the density matrix and Maxwell s equations. This allows to accommodate a variety of nonlinear effects which accomplish the propagation of strong light pulses. Particular attention is paid to the understanding of the role of coherent and sequential excitations of electron-nuclear degrees of freedom. The QMED combination of quantum chemistry with classical pulse propagation allows to estimate the optical transmission from cross sections of multi-photon absorption processes and from considerations of propagation effects, saturation and pulse effects. Results of the theory suggest that in the nonlinear regime it is often necessary to account simultaneously for coherent one-step and incoherent step-wise multi-photon absorption, as well as for off-resonant excitations even when resonance conditions prevail. The dynamic theory of nonlinear propagation of a few interacting intense light pulses is here highlighted in a study of the optical power limiting with platinum-organic molecular compounds. © 2007 Materials Research Society.
  •  
20.
  • Baev, Alexander, et al. (författare)
  • Metaphotonics : An emerging field with opportunities and challenges
  • 2015
  • Ingår i: Physics reports. - : Elsevier. - 0370-1573 .- 1873-6270. ; 594, s. 1-60
  • Forskningsöversikt (refereegranskat)abstract
    • Metaphotonics is an emerging multidisciplinary field that deals with manipulation of electro-magnetic fields in nanoengineered (meta)materials using both electric and magnetic interactions and their cross-coupling. It offers unprecedented control of both linear and nonlinear optical functions for applications ranging from optical switching, to negative- and near-zero refractive index metamaterials, to chiral bioimaging, to cloaking. However, realization of such applications requires physics-guided nanoengineering of appropriate artificial media with electro-magnetic properties at visible and infrared wavelengths that are tailored to surpass those of any naturally-occurring material. Here, we review metaphotonics with a broadened vision and scope, introduce potential applications, describe the role of theoretical physics through multiscale modeling, review the materials development and current status, and outline opportunities in this fertile emerging field.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 11-20 av 952
Typ av publikation
tidskriftsartikel (822)
annan publikation (43)
doktorsavhandling (33)
forskningsöversikt (20)
konferensbidrag (12)
bokkapitel (12)
visa fler...
licentiatavhandling (10)
visa färre...
Typ av innehåll
refereegranskat (842)
övrigt vetenskapligt/konstnärligt (110)
Författare/redaktör
Gelmukhanov, Faris (102)
Li, Xin (94)
Rinkevicius, Zilvina ... (76)
Luo, Yi (72)
Tu, Yaoquan (66)
visa fler...
Vahtras, Olav (62)
Baryshnikov, Gleb V. (59)
Ågren, Hans, 1945 (45)
Salek, Pawel (43)
Baryshnikov, Glib (41)
Minaev, Boris F. (38)
Natarajan Arul, Muru ... (35)
Xie, Yongshu (34)
Fu, Ying (33)
Kuklin, Artem V. (31)
Minaev, Boris (31)
Kongsted, Jacob (26)
Ågren, Hans, Profess ... (24)
Zhu, Liangliang (24)
Norman, Patrick (23)
Carravetta, Vincenzo (22)
Prasad, Paras N. (21)
Chen, Guanying (21)
Valiev, Rashid R. (20)
Li, Qizhao (20)
Kimberg, Victor (20)
Liu, Haichun (19)
Li, Chengjie (19)
Baev, A. (19)
Zaleśny, Robert (18)
Rubensson, Jan-Erik (17)
Carravetta, V. (17)
Baev, Alexander (17)
Zhang, Qiong (16)
Zhang, Han (16)
Ning, Zhijun (16)
Polyutov, Sergey (15)
Murugan, N. Arul (14)
Monti, Susanna (14)
Nordberg, Agneta (13)
Sorensen, S. L. (13)
Leck, Caroline (13)
Ruud, K. (13)
Svensson, S (12)
Långström, Bengt (12)
Widengren, Jerker (12)
Sun, Licheng (12)
Miron, C. (12)
Zhao, Yanli (12)
visa färre...
Lärosäte
Kungliga Tekniska Högskolan (785)
Uppsala universitet (162)
Linköpings universitet (74)
Göteborgs universitet (51)
Karolinska Institutet (32)
Stockholms universitet (26)
visa fler...
Lunds universitet (21)
Örebro universitet (10)
Umeå universitet (6)
Högskolan i Gävle (3)
Mälardalens universitet (2)
Chalmers tekniska högskola (2)
Högskolan i Halmstad (1)
Mittuniversitetet (1)
Linnéuniversitetet (1)
RISE (1)
Sveriges Lantbruksuniversitet (1)
visa färre...
Språk
Engelska (941)
Svenska (8)
Odefinierat språk (3)
Forskningsämne (UKÄ/SCB)
Naturvetenskap (684)
Medicin och hälsovetenskap (66)
Teknik (65)
Samhällsvetenskap (1)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy