| 1. |
- Campbell, PJ, et al.
(författare)
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Pan-cancer analysis of whole genomes
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 578:7793, s. 82-
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Tidskriftsartikel (refereegranskat)abstract
- Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale1–3. Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4–5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter4; identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation5,6; analyses timings and patterns of tumour evolution7; describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity8,9; and evaluates a range of more-specialized features of cancer genomes8,10–18.
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| 2. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 3. |
- Sato, T., et al.
(författare)
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Overview of particle and heavy ion transport code system PHITS
- 2015
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Ingår i: Annals of Nuclear Energy. - : Elsevier BV. - 0306-4549 .- 1873-2100. ; 82, s. 110-115
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Tidskriftsartikel (refereegranskat)abstract
- A general purpose Monte Carlo Particle and Heavy Ion Transport code System, PHITS, is being developed through the collaboration of several institutes in Japan and Europe. The Japan Atomic Energy Agency is responsible for managing the entire project. PHITS can deal with the transport of nearly all particles, including neutrons, protons, heavy ions, photons, and electrons, over wide energy ranges using various nuclear reaction models and data libraries. It is written in Fortran language and can be executed on almost all computers. All components of PHITS such as its source, executable and data-library files are assembled in one package and then distributed to many countries via the Research Organization for Information Science and Technology, the Data Bank of the Organization for Economic Co-operation and Development's Nuclear Energy Agency, and the Radiation Safety Information Computational Center. More than 1500 researchers have been registered as PHITS users, and they apply the code to various research and development fields such as nuclear technology, accelerator design, medical physics, and cosmic-ray research. This paper briefly summarizes the physics models implemented in PHITS, and introduces some important functions useful for specific applications, such as an event generator mode and beam transport functions. (C) 2014 Elsevier Ltd. All rights reserved.
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| 4. |
- Sato, T., et al.
(författare)
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Overview of Particle and Heavy Ion Transport Code System PHITS
- 2014
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Ingår i: Sna + Mc 2013 - Joint International Conference on Supercomputing in Nuclear Applications + Monte Carlo. - Les Ulis, France : EDP Sciences. ; , s. article no 06018-
-
Konferensbidrag (refereegranskat)abstract
- A general purpose Monte Carlo Particle and Heavy Ion Transport code System, PHITS, is being developed through the collaboration of several institutes in Japan and Europe. The Japan Atomic Energy Agency is responsible for managing the entire project. PHITS can deal with the transport of nearly all particles, including neutrons, protons, heavy ions, photons, and electrons, over wide energy ranges using various nuclear reaction models and data libraries. It is written in Fortran language and can be executed on almost all computers. All components of PHITS such as its source, executable and data-library files are assembled in one package and then distributed to many countries via the Research organization for Information Science and Technology, the Data Bank of the Organization for Economic Co-operation and Development's Nuclear Energy Agency, and the Radiation Safety Information Computational Center. More than 1,000 researchers have been registered as PHITS users, and they apply the code to various research and development fields such as nuclear technology, accelerator design, medical physics, and cosmic-ray research. This paper briefly summarizes the physics models implemented in PHITS, and introduces some important functions useful for specific applications, such as an event generator mode and beam transport functions.
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| 5. |
- Sato, T., et al.
(författare)
-
Particle and Heavy Ion Transport code System, PHITS, version 2.52
- 2013
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Ingår i: Journal of Nuclear Science and Technology. - : Informa UK Limited. - 0022-3131 .- 1881-1248. ; 50:9, s. 913-923
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Tidskriftsartikel (refereegranskat)abstract
- An upgraded version of the Particle and Heavy Ion Transport code System, PHITS2.52, was developed and released to the public. The new version has been greatly improved from the previously released version, PHITS2.24, in terms of not only the code itself but also the contents of its package, such as the attached data libraries. In the new version, a higher accuracy of simulation was achieved by implementing several latest nuclear reaction models. The reliability of the simulation was improved by modifying both the algorithms for the electron-, positron-, and photon-transport simulations and the procedure for calculating the statistical uncertainties of the tally results. Estimation of the time evolution of radioactivity became feasible by incorporating the activation calculation program DCHAIN-SP into the new package. The efficiency of the simulation was also improved as a result of the implementation of shared-memory parallelization and the optimization of several time-consuming algorithms. Furthermore, a number of new user-support tools and functions that help users to intuitively and effectively perform PHITS simulations were developed and incorporated. Due to these improvements, PHITS is now a more powerful tool for particle transport simulation applicable to various research and development fields, such as nuclear technology, accelerator design, medical physics, and cosmic-ray research.
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| 6. |
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| 7. |
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| 8. |
- Smith, RM, et al.
(författare)
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Rituximab as therapy to induce remission after relapse in ANCA-associated vasculitis
- 2020
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Ingår i: Annals of the rheumatic diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 79:9, s. 1243-1249
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Tidskriftsartikel (refereegranskat)abstract
- Evaluation of rituximab and glucocorticoids as therapy to induce remission after relapse in ANCA-associated vasculitis (AAV) in a prospective observational cohort of patients enrolled into the induction phase of the RITAZAREM trial.MethodsPatients relapsing with granulomatosis with polyangiitis or microscopic polyangiitis were prospectively enrolled and received remission-induction therapy with rituximab (4×375 mg/m2) and a higher or lower dose glucocorticoid regimen, depending on physician choice: reducing from either 1 mg/kg/day or 0.5 mg/kg/day to 10 mg/day by 4 months. Patients in this cohort achieving remission were subsequently randomised to receive one of two regimens to prevent relapse.Results188 patients were studied: 95/188 (51%) men, median age 59 years (range 19–89), prior disease duration 5.0 years (range 0.4–34.5). 149/188 (79%) had previously received cyclophosphamide and 67/188 (36%) rituximab. 119/188 (63%) of relapses had at least one major disease activity item, and 54/188 (29%) received the higher dose glucocorticoid regimen. 171/188 (90%) patients achieved remission by 4 months. Only six patients (3.2% of the study population) did not achieve disease control at month 4. Four patients died in the induction phase due to pneumonia (2), cerebrovascular accident (1), and active vasculitis (1). 41 severe adverse events occurred in 27 patients, including 13 severe infections.ConclusionsThis large prospective cohort of patients with relapsing AAV treated with rituximab in conjunction with glucocorticoids demonstrated a high level of efficacy for the reinduction of remission in patients with AAV who have relapsed, with a similar safety profile to previous studies.
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| 9. |
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| 10. |
- Smith, RM, et al.
(författare)
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Rituximab versus azathioprine for maintenance of remission for patients with ANCA-associated vasculitis and relapsing disease: an international randomised controlled trial
- 2023
-
Ingår i: Annals of the rheumatic diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 82:7, s. 937-944
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Tidskriftsartikel (refereegranskat)abstract
- Following induction of remission with rituximab in anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) relapse rates are high, especially in patients with history of relapse. Relapses are associated with increased exposure to immunosuppressive medications, the accrual of damage and increased morbidity and mortality. The RITAZAREM trial compared the efficacy of repeat-dose rituximab to daily oral azathioprine for prevention of relapse in patients with relapsing AAV in whom remission was reinduced with rituximab.MethodsRITAZAREM was an international randomised controlled, open-label, superiority trial that recruited 188 patients at the time of an AAV relapse from 29 centres in seven countries between April 2013 and November 2016. All patients received rituximab and glucocorticoids to reinduce remission. Patients achieving remission by 4 months were randomised to receive rituximab intravenously (1000 mg every 4 months, through month 20) (85 patients) or azathioprine (2 mg/kg/day, tapered after month 24) (85 patients) and followed for a minimum of 36 months. The primary outcome was time to disease relapse (either major or minor relapse).ResultsRituximab was superior to azathioprine in preventing relapse: HR 0.41; 95% CI 0.27 to 0.61, p<0.001. 19/85 (22%) patients in the rituximab group and 31/85 (36%) in the azathioprine group experienced at least one serious adverse event during the treatment period. There were no differences in rates of hypogammaglobulinaemia or infection between groups.ConclusionsFollowing induction of remission with rituximab, fixed-interval, repeat-dose rituximab was superior to azathioprine for preventing disease relapse in patients with AAV with a prior history of relapse.Trial registration numberNCT01697267; ClinicalTrials.gov identifier
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| 11. |
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| 12. |
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| 13. |
- Buyanova, Irina, et al.
(författare)
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Spin dynamics in ZnO-based materials
- 2010
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Ingår i: Journal of Superconductivity and Novel Magnetism. - New York, USA : Springer-Verlag New York. - 1557-1939 .- 1557-1947. ; 23:1, s. 161-165
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we address the issue of spin relaxation and its relevance to spin detection in ZnO-based materials, by spin-polarized, time-resolved magneto-optical spectroscopy. We have found that spin relaxation is very fast, i.e. about 100 ps for donor bound excitons in wurtzite ZnO, despite of a weak spin–orbit interaction. We also reveal that alloying of ZnO with Cd enhances spin relaxation, prohibiting ZnCdO/ZnO structures for efficient optical spin detection. On the other hand, a variation in strain field induced by lattice mismatch with substrates does not seem to lead to a noticeable change in spin relaxation. The observed fast spin relaxation, together with the limitation imposed by the band structure, are thus identified as the two most important factors that limit the efficiency of optical spin detection in the studied ZnO-based materials.
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| 14. |
- Chen, Weimin, 1959-, et al.
(författare)
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Dominant factors limiting efficiency of optical spin detection in ZnO-based materials
- 2008
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 92, s. 092103-
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Tidskriftsartikel (refereegranskat)abstract
- Two dominant factors limiting efficiency of optical spin detection in ZnO-based materials system are identified from time-resolved optical orientation and magneto-optical studies. The first is related to the fundamental band structure of the materials characterized by a weak spin-orbit interaction. It leads to cancellation of circular polarization from the optical transitions between the conduction band and the A and B valence band states, which would otherwise carry the desired information on spin polarization of carriers. The second limiting factor is shown to be efficient carrier/exciton spin relaxation, i.e., about 45-80 ps.
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| 15. |
- Coleman, M., et al.
(författare)
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Hyaluronidase Impairs Neutrophil Function and Promotes Group B Streptococcus Invasion and Preterm Labor in Nonhuman Primates
- 2021
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Ingår i: Mbio. - 2150-7511. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- Invasive bacterial infections during pregnancy are a major risk factor for preterm birth, stillbirth, and fetal injury. Group B streptococci (GBS) are Gram-positive bacteria that asymptomatically colonize the lower genital tract but infect the amniotic fluid and induce preterm birth or stillbirth. Experimental models that closely emulate human pregnancy are pivotal for the development of successful strategies to prevent these adverse pregnancy outcomes. Using a unique nonhuman primate model that mimics human pregnancy and informs temporal events surrounding amniotic cavity invasion and preterm labor, we show that the animals inoculated with hyaluronidase (HylB)-expressing GBS consistently exhibited microbial invasion into the amniotic cavity, fetal bacteremia, and preterm labor. Although delayed cytokine responses were observed at the maternal-fetal interface, increased prostaglandin and matrix metalloproteinase levels in these animals likely mediated pre term labor. HylB-proficient GBS dampened reactive oxygen species production and exhibited increased resistance to neutrophils compared to an isogenic mutant. Together, these findings demonstrate how a bacterial enzyme promotes GBS amniotic cavity invasion and preterm labor in a model that closely resembles human pregnancy. IMPORTANCE Group B streptococci (GBS) are bacteria that commonly reside in the female lower genital tract as asymptomatic members of the microbiota. However, during pregnancy, GBS can infect tissues at the maternal-fetal interface, leading to preterm birth, stillbirth, or fetal injury. Understanding how GBS evade host defenses during pregnancy is key to developing improved preventive therapies for these adverse outcomes. In this study, we used a unique nonhuman primate model to show that an enzyme secreted by GBS, hyaluronidase (HylB) promotes bacterial invasion into the amniotic cavity and fetus. Although delayed immune responses were seen at the maternal-fetal interface, animals infected with hyaluronidase-expressing GBS exhibited premature cervical ripening and preterm labor. These observations reveal that HylB is a crucial GBS virulence factor that promotes bacterial invasion and preterm labor in a pregnancy model that closely emulates human pregnancy. Therefore, hyaluronidase inhibitors may be useful in therapeutic strategies against ascending GBS infection.
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| 16. |
- Dagnelund, Daniel, 1980-, et al.
(författare)
-
Carrier and spin injection from ZnMnSe to CdSe quantum dots
- 2008
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Optical carrier/exction and spin injection processes from a ZnMnSe dilute magnetic semiconductor (DMS) to CdSe quantum dots (QD’s) are studied in detail by means of spinpolarized magneto- photoluminescence (PL) and PL excitation spectroscopies. Efficiency of carrier/exciton transfer is found to be practically independent of width (Lb) of a ZnSe barrier layer inserted between the DMS and QD’s. This is tentatively explained in terms of photonexchange energy transfer. In sharp contrast, spin injection efficiency is found to be largely suppressed in the structures with large Lb, pointing towards increasing spin loss.
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| 17. |
- Dagnelund, Daniel, et al.
(författare)
-
Carrier and spin injection from ZnMnSe to CdSe quantum dots
- 2009
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Optical carrier/exction and spin injection processes from a ZnMnSe dilute magnetic semiconductor (DMS) to CdSe quantum dots (QD’s) are studied in detail by means of spinpolarized magneto- photoluminescence (PL) and PL excitation spectroscopies. Efficiency of carrier/exciton transfer is found to be practically independent of width (Lb) of a ZnSe barrier layer inserted between the DMS and QD’s. This is tentatively explained in terms of photonexchange energy transfer. In sharp contrast, spin injection efficiency is found to be largely suppressed in the structures with large Lb, pointing towards increasing spin loss.
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| 18. |
- Dagnelund, Daniel, et al.
(författare)
-
Carrier and Spin Injection from ZnMnSe to CdSe Quantum Dots
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Optical carrier/exction and spin injection processes from a ZnMnSe dilute magnetic semiconductor (DMS) to CdSe quantum dots (QD’s) are studied in detail by means of spinpolarized magneto- photoluminescence (PL) and PL excitation spectroscopies. Efficiency of carrier/exciton transfer is found to be practically independent of width (Lb) of a ZnSe barrier layer inserted between the DMS and QD’s. This is tentatively explained in terms of photonexchange energy transfer. In sharp contrast, spin injection efficiency is found to be largely suppressed in the structures with large Lb, pointing towards increasing spin loss.
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| 19. |
- Dagnelund, Daniel, 1980-, et al.
(författare)
-
Efficiency of optical spin injection and spin loss from a diluted magnetic semiconductor ZnMnSe to CdSe nonmagnetic quantum dots
- 2008
-
Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 77:3, s. 035437-
-
Tidskriftsartikel (refereegranskat)abstract
- Magneto-optical spectroscopy in combination with tunable laser spectroscopy is employed to study optical spin injection from a diluted magnetic semiconductor (DMS) ZnMnSe into nonmagnetic CdSe quantum dots (QDs). Observation of a DMS feature in the excitation spectra of the QD photoluminescence polarization provides clear evidence for optical spin-injection from the DMS to the QDs. By means of a rate equation analysis, the injected spin polarization is deduced to be about 32% at 5 T, decreasing from 100% before the injection. The observed spin loss is shown to occur during the spin injection process including crossing the heterointerfaces and energy relaxation within the QDs. © 2008 The American Physical Society.
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| 20. |
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| 21. |
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| 22. |
- Dagnelund, Daniel, et al.
(författare)
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Magneto-optical and tunable laser excitation spectroscopy of spin-injection and spin loss from Zn(Cd)MnSe diluted magnetic quantum well to CdSe non-magnetic quantum dots
- 2008
-
Konferensbidrag (refereegranskat)abstract
- Magneto-optical spectroscopy in combination with tunable laser spectroscopy is employed to study the effect of sample design on optical spin-injection efficiency from a Zn(Cd)MnSe diluted magnetic semiconductor (DMS) into non-magnetic CdSe quantum dots (QDs). Two samples with inverted growth sequence of the DMS and QD layers were grown for this purpose. Despite observation of clear evidence for exciton/carrier-injection from the DMS to the QDs in both structures, their spin-injection efficiency is markedly different. The structure grown with the QD layer topmost exhibits rather efficient spin-injection, while the structure grown with the DMS layer topmost does not show any sign of spin-injection. Even in the former case, the spin-polarization of the injected excitons/carriers is deduced to be about 32%, decreasing from 100% before the injection. The observed spin loss is shown to occur during the spin-injection across the heterointerfaces. © 2007 Elsevier B.V. All rights reserved.
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| 23. |
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| 24. |
- Dagnelund, Daniel, et al.
(författare)
-
Spin injection in a coupled system of a diluted magnetic semiconductor Zn0.80Mn0.20Se and self-assembled quantum dots of CdSe
- 2008
-
Ingår i: Proceedings of the 7th International Conference on Physics of Light-Matter Coupling in Nanostructures. - : Elsevier BV. ; , s. 615-619
-
Konferensbidrag (refereegranskat)abstract
- Spin injection processes from a Zn0.80Mn0.20Se diluted magnetic semiconductor (DMS) to adjacent self-assembled CdSe quantum dots (QDs) were investigated by cw and time-resolved magneto-optical spectroscopy in combination with tunable laser excitation. Direct experimental evidence for the spin injection was provided from the generation of the spin polarization in the QDs, which was opposite to their expected intrinsic polarization, by resonantly generating the spins in the DMS. The observed limited spin polarization generated by the spin injection, together with the sensitivity of the spin injection efficiency on structure design, indicates severe spin loss during the process and calls for further investigations to optimize spin injection efficiency in quantum structures. © 2007 Elsevier Ltd. All rights reserved.
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| 25. |
- Danno, A., et al.
(författare)
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Effect of cold severe deformation by multi directional forging on elastic modulus of multi functional Ti+25mol% (Ta,Nb,V)+(Zr,Hr,O) alloy
- 2010
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Ingår i: Materials & Design. - : Elsevier BV. - 0261-3069. ; 31:SUPPL. 1, s. S61-S65
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Tidskriftsartikel (refereegranskat)abstract
- A new and unique beta-titanium alloy (Ti. +. 25. mol% (Ta,Nb,V). +. (Zr,Hr,O) has interesting properties such as low elastic modulus, high strength and high elastic deformability as well as Invar and Elinvar properties. These properties have been successfully realized for the round wire or rods by cold working process but not enough for the sheet made by the cold rolling.To improve the mechanical properties of the alloy sheet, the effect of cold severe deformation on the elastic modulus and microstructure of the alloy sheet was experimentally investigated. The samples were processed using the multi directional forging (MDF) and cold plain rolling.The elastic modulus of the alloy sheet which was cold rolled after MDF was lower than that of cold rolled sheet without MDF. The severe cold plastic deformation by MDF was also effective for obtaining isotropic elastic modulus and very fine grain size (∌1ÎŒm) of sheet after plain rolling. The prototype sheet with low elastic modulus (60-65. GPa), high strength (1100. MPa) and high ductility (total elongation more than 10%) was successfully made in the laboratory test by combining MDF and plain rolling at room temperature. © 2009 Elsevier Ltd.
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| 26. |
- Feifel, R, et al.
(författare)
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Probing doubly excited ionic states of N-2(+) via a triple excitation above the N 1s threshold in the N-2 molecule
- 2003
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 67:3: 032504
-
Tidskriftsartikel (refereegranskat)abstract
- Angle-resolved resonant Auger-electron spectroscopy has been carried out on the nitrogen molecule at selected photon energies around 419 eV, where a 1s core electron and two valence electrons are promoted into the lowest unoccupied molecular orbital 1pi(g). Significant enhancement of a specific band, which cannot be disentangled in direct photoionization, is observed at a binding energy of 37.6 eV, with a value of the anisotropy parameter beta much smaller than 2. We assign this new band to the transition to a doubly excited cationic state of N-2, in which two of the excited valence electrons remain in the 1pi(g) orbital, proposing a "double spectator" type decay mechanism. This observation shows how to preferentially probe multiply excited configurations of cations using multiple resonant excitation.
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| 27. |
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| 28. |
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| 29. |
- Furuta, T., et al.
(författare)
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Spin-injection dynamics and effects of spin relaxation in self-assembled quantum dots of CdSe
- 2008
-
Ingår i: Journal of the Korean Physical Society. - 0374-4884 .- 1976-8524. ; 53, s. 163-166
-
Tidskriftsartikel (refereegranskat)abstract
- We study the spin injection dynamics and the effects of spin relaxation in self-assembled quantum dots (QDs) of CdSe coupled with a diluted magnetic semiconductor (DMS) layer of ZnMnSe, where spin-polarized excitons can be injected from the DMS into the QDs because of the potential difference. The degree of circular polarization, $P$, of excitonic photoluminescence (PL) at 5 T in the coupled QDs shows a rapid increase with increasing delay time after a linearly polarized pulse excitation, indicating the spin-injection dynamics. The $P$ value tends to decay gradually because of the exciton-spin relaxation in the QDs after the spin injection. The spin-polarized excitons in the QD ensemble migrate simultaneously from QDs with higher exciton energies to those with lower exciton energies. This inter-dot transfer of excitons also affects the $P$ value in the lower energy region of the QD-emission band because the excitons lose their spin polarizations due to the spin relaxation in the dots during the migration. The detailed analysis for the exciton-spin transfer is presented in a coupled QD system after spin injection.
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| 30. |
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| 31. |
- Kitajima, M., et al.
(författare)
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Doppler effect in resonant photoemission from SF6 : Correlation between doppler profile and auger emission anisotropy
- 2003
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 91:21
-
Tidskriftsartikel (refereegranskat)abstract
- Fragmentation of the SF6 molecule upon F 1s excitation has been studied by resonant photoemission. The F atomiclike Auger line exhibits the characteristic Doppler profile that depends on the direction of the photoelectron momentum relative to the polarization vector of the radiation as well as on the photon energy. The measured Doppler profiles are analyzed by the model simulation that takes account of the anisotropy of the Auger emission in the molecular frame. The Auger anisotropy extracted from the data decreases with an increase in the F-SF5 internuclear distance.
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| 32. |
- Li, M., et al.
(författare)
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Non-human Primate Models to Investigate Mechanisms of Infection-Associated Fetal and Pediatric Injury, Teratogenesis and Stillbirth
- 2021
-
Ingår i: Frontiers in Genetics. - : Frontiers Media SA. - 1664-8021. ; 12
-
Forskningsöversikt (refereegranskat)abstract
- A wide array of pathogens has the potential to injure the fetus and induce teratogenesis, the process by which mutations in fetal somatic cells lead to congenital malformations. Rubella virus was the first infectious disease to be linked to congenital malformations due to an infection in pregnancy, which can include congenital cataracts, microcephaly, hearing impairment and congenital heart disease. Currently, human cytomegalovirus (HCMV) is the leading infectious cause of congenital malformations globally, affecting 1 in every 200 infants. However, our knowledge of teratogenic viruses and pathogens is far from complete. New emerging infectious diseases may induce teratogenesis, similar to Zika virus (ZIKV) that caused a global pandemic in 2016-2017; thousands of neonates were born with congenital microcephaly due to ZIKV exposure in utero, which also included a spectrum of injuries to the brain, eyes and spinal cord. In addition to congenital anomalies, permanent injury to fetal and neonatal organs, preterm birth, stillbirth and spontaneous abortion are known consequences of a broader group of infectious diseases including group B streptococcus (GBS), Listeria monocytogenes, Influenza A virus (IAV), and Human Immunodeficiency Virus (HIV). Animal models are crucial for determining the mechanism of how these various infectious diseases induce teratogenesis or organ injury, as well as testing novel therapeutics for fetal or neonatal protection. Other mammalian models differ in many respects from human pregnancy including placentation, labor physiology, reproductive tract anatomy, timeline of fetal development and reproductive toxicology. In contrast, non-human primates (NHP) most closely resemble human pregnancy and exhibit key similarities that make them ideal for research to discover the mechanisms of injury and for testing vaccines and therapeutics to prevent teratogenesis, fetal and neonatal injury and adverse pregnancy outcomes (e.g., stillbirth or spontaneous abortion). In this review, we emphasize key contributions of the NHP model pre-clinical research for ZIKV, HCMV, HIV, IAV, L. monocytogenes, Ureaplasma species, and GBS. This work represents the foundation for development and testing of preventative and therapeutic strategies to inhibit infectious injury of human fetuses and neonates.
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| 33. |
- Murayama, A., et al.
(författare)
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Dynamics of exciton-spin injection, transfer, and relaxation in self-assembled quantum dots of CdSe coupled with a diluted magnetic semiconductor layer of Zn0.80 Mn0.20 Se
- 2007
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 75:19, s. 195308-
-
Tidskriftsartikel (refereegranskat)abstract
- We study the dynamics of exciton-spin injection, transfer, and relaxation in self-assembled quantum dots (QDs) of CdSe coupled with a diluted magnetic semiconductor (DMS) layer of Zn0.80 Mn0.20 Se, where spin-polarized excitons can be injected from the DMS into the QDs. The degree of circular polarization P of excitonic photoluminescence (PL) at 5 T in the coupled QDs exhibits a rapid increase with increasing delay time, up to +0.3 at 25 ps after the pulse excitation of the DMS by a linearly polarized light. This development of a positive P value directly reflects the spin-injection dynamics from the DMS, since the intrinsic polarization of the QD excitons due to Zeeman splitting is P∼-0.1 when only the QDs are selectively excited. The P value gradually decays with time after reaching its maximum, as a result of the exciton-spin relaxation with a time constant of 800 ps in the QDs. Time-resolved circularly polarized PL spectra immediately after the pulse excitation directly show the exciton-energy dependence of the spin-injection dynamics in the QD ensemble, where two-dimensional-like QDs with higher exciton energies show higher receptivity to the spin-polarized excitons than three-dimensional-like dots with lower exciton energies. A rate equation analysis reveals all time constants responsible for the spin-injection dynamics. We deduce a time constant of 10 ps for the spin injection. The spin-injection efficiency of 0.94 is also obtained, which corresponds to the ratio between the number of the spin-polarized excitons responsible for the rise of the positive P value in the QD emission and the total number of the excitons injected from the DMS. Moreover, we observe that interdot exciton transfer significantly affects the P value within the QD emission band after the fast spin injection, in addition to the spin relaxation within the QDs. © 2007 The American Physical Society.
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| 34. |
- Murayama, A., et al.
(författare)
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Propagation dynamics of exciton spins in a high-density semiconductor quantum dot system
- 2009
-
Ingår i: physica status solidi c. - : phys. stat. sol. c. - 1862-6351 .- 1610-1642.
-
Konferensbidrag (refereegranskat)abstract
- We study propagation dynamics of exciton spins in a system composed of high-density self-assembled quantum dots (QDs) of CdSe and a diluted magnetic semiconductor (DMS) layer of ZnMnSe, where spin-polarized excitons are generated in the DMS layer and are subsequently injected into the QDs. The degree of circular polarization, P, of excitonic photoluminescence at 5 T in the coupled QDs shows a rapid increase with increasing delay time after a linearly polarized pulsed excitation, indicating the exciton-spin injection from the ZnMnSe to CdSe-QDs. The P value tends to decay gradually because of the exciton-spin relaxation in the QDs after the injection. The spin-polarized excitons in the QD ensemble migrate simultaneously from the QDs with higher exciton energies to those with lower exciton energies, where the exciton-spins relax inside each dot during the migration. Therefore, the observed P values in the QD emission band are affected by this feeding of the relaxed spins.
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| 35. |
- Murayama, A, et al.
(författare)
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Transfer dynamics of spin-polarized excitons into semiconductor quantum dots
- 2009
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Ingår i: Journal of Luminescence. - : Elsevier BV. - 0022-2313 .- 1872-7883. ; 129, s. 1927-1930
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Tidskriftsartikel (refereegranskat)abstract
- We study on the transfer dynamics of spin-polarized excitons into self-assembled quantum dots (QDs) of CdSe coupled with a diluted magnetic semiconductor (DMS) layer of ZnMnSe through a ZnSe barrier layer. A variation in the degree of circular polarization P of excitonic photoluminescence in the coupled QDs was observed between samples with different thicknesses (LB) of the non-magnetic barrier. Relatively high values of P (0.3) were obtained in the samples with LB=1 or 2 nm, and the time dependences of the P value indicate the spin-transfer dynamics. From the LB dependence of the spin-transfer time, the spin-transfer mechanism is discussed, namely spin-conserving energy transfer.
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| 36. |
- R. Feifel, K. Ueda, A. De Fanis, K. Okada, S. Tanimoto, T. Furuta, H. Shindo, M. Kitajima, H. Tanaka, O. Björneholm, L. Karlsson, S. Svensson and S. L. Sorensen
(författare)
-
Probing doubly excited ionic states of N2+ via a triple excitation above the N1s threshold in the N2 moecule
- 2003
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Ingår i: Phys. Rev.. ; A:67, s. 32504-
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Tidskriftsartikel (refereegranskat)
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| 37. |
- Ueda, K, et al.
(författare)
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Anisotropic ultrafast dissociation probed by the Doppler effect in resonant photoemission from CF4
- 2003
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Ingår i: Physical Review Letters. - 1079-7114. ; 90:23: 233006
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Tidskriftsartikel (refereegranskat)abstract
- The resonant Auger spectrum from the decay of F 1s-excited CF4 is measured. Several lines exhibit a nondispersive kinetic energy as the exciting photon energy is tuned through the resonance region. The F 1s(-1) atomiclike Auger line is split into two components due to the emission of Auger electrons by a fragment in motion, when electron emission is observed along the polarization vector of the light. This Doppler splitting is direct evidence that the core excitation leads to T-d-->C-3v symmetry lowering, by elongation of a specific C-F bond preferentially aligned along the polarization vector of the incident photon.
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| 38. |
- Ueda, K, et al.
(författare)
-
Nuclear motion and symmetry breaking of the B 1s-excited BF3 molecule
- 2003
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Ingår i: Chemical Physics. - 0301-0104. ; 289:1, s. 135-147
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Tidskriftsartikel (refereegranskat)abstract
- Out-of-plane nuclear motion stimulated in the core-excited state and symmetry breaking due to this nuclear motion have been investigated for B Is excitation in the BF3 molecule by a combination of three different experimental methods: angle-resolved ion-yield spectroscopy, vibrationally resolved resonant Auger electron spectroscopy and quadruple-ion coincidence momentum-imaging technique. (C) 2002 Elsevier Science B.V. All rights reserved.
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