| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
| 11. |
- Klionsky, Daniel J., et al.
(författare)
-
Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
-
Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
-
Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
|
|
| 12. |
- Abramowski, A., et al.
(författare)
-
Revisiting the Westerlund 2 field with the HESS telescope array
- 2011
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 525, s. A46-
-
Tidskriftsartikel (refereegranskat)abstract
- Aims. Previous observations with the HESS telescope array revealed the existence of extended very-high-energy (VHE; E > 100 GeV) gamma-ray emission, HESS J1023-575, coincident with the young stellar cluster Westerlund 2. At the time of discovery, the origin of the observed emission was not unambiguously identified, and follow-up observations have been performed to further investigate the nature of this gamma-ray source. Methods. The Carina region towards the open cluster Westerlund 2 has been re-observed, increasing the total exposure to 45.9 h. The combined dataset includes 33 h of new data and now permits a search for energy-dependent morphology and detailed spectroscopy. Results. A new, hard spectrum VHE gamma-ray source, HESS J1026-582, was discovered with a statistical significance of 7 sigma. It is positionally coincident with the Fermi LAT pulsar PSRJ1028-5819. The positional coincidence and radio/gamma-ray characteristics of the LAT pulsar favors a scenario where the TeV emission originates from a pulsar wind nebula. The nature of HESS J1023-575 is discussed in light of the deep HESS observations and recent multi-wavelength discoveries, including the Fermi LAT pulsar PSRJ1022-5746 and giant molecular clouds in the region. Despite the improved VHE dataset, a clear identification of the object responsible for the VHE emission from HESS J1023-575 is not yet possible, and contribution from the nearby high-energy pulsar and/or the open cluster remains a possibility.
|
|
| 13. |
- Furukawa, T. A., et al.
(författare)
-
Dismantling, optimising, and personalising internet cognitive behavioural therapy for depression: a systematic review and component network meta-analysis using individual data
- 2021
-
Ingår i: Lancet Psychiatry. - : Elsevier BV. - 2215-0374 .- 2215-0366. ; 8:6, s. 500-511
-
Tidskriftsartikel (refereegranskat)abstract
- Findings We identified 76 RCTs, including 48 trials contributing individual participant data (11 704 participants) and 28 trials with aggregate data (6474 participants). The participants' weighted mean age was 42.0 years and 12 406 (71%) of 17 521 reported were women. There was suggestive evidence that behavioural activation might be beneficial (iMD -1.83 [95% credible interval (CrI) -2.90 to -0.80]) and that relaxation might be harmful (1.20 [95% CrI 0.17 to 2.27]). Baseline severity emerged as the strongest prognostic factor for endpoint depression. Combining human and automated encouragement reduced dropouts from treatment (incremental odds ratio, 0.32 [95% CrI 0.13 to 0.93]). The risk of bias was low for the randomisation process, missing outcome data, or selection of reported results in most of the included studies, uncertain for deviation from intended interventions, and high for measurement of outcomes. There was moderate to high heterogeneity among the studies and their components. 511
|
|
| 14. |
- Ellinor, Patrick T., et al.
(författare)
-
Meta-analysis identifies six new susceptibility loci for atrial fibrillation
- 2012
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 44:6, s. 88-670
-
Tidskriftsartikel (refereegranskat)abstract
- Atrial fibrillation is a highly prevalent arrhythmia and a major risk factor for stroke, heart failure and death(1). We conducted a genome-wide association study (GWAS) in individuals of European ancestry, including 6,707 with and 52,426 without atrial fibrillation. Six new atrial fibrillation susceptibility loci were identified and replicated in an additional sample of individuals of European ancestry, including 5,381 subjects with and 10,030 subjects without atrial fibrillation (P < 5 x 10(-8)). Four of the loci identified in Europeans were further replicated in silico in a GWAS of Japanese individuals, including 843 individuals with and 3,350 individuals without atrial fibrillation. The identified loci implicate candidate genes that encode transcription factors related to cardiopulmonary development, cardiac-expressed ion channels and cell signaling molecules.
|
|
| 15. |
- Fujita, S., et al.
(författare)
-
Spatial and temporal variability of snow accumulation rate on the East Antarctic ice divide between Dome Fuji and EPICA DML
- 2011
-
Ingår i: The Cryosphere. - : Copernicus GmbH. - 1994-0416 .- 1994-0424. ; 5:4, s. 1057-1081
-
Tidskriftsartikel (refereegranskat)abstract
- To better understand the spatio-temporal variability of the glaciological environment in Dronning Maud Land (DML), East Antarctica, a 2800-km-long Japanese-Swedish traverse was carried out. The route includes ice divides between two ice-coring sites at Dome Fuji and EPICA DML. We determined the surface mass balance (SMB) averaged over various time scales in the late Holocene based on studies of snow pits and firn cores, in addition to radar data. We find that the large-scale distribution of the SMB depends on the surface elevation and continentality, and that the SMB differs between the windward and leeward sides of ice divides for strong-wind events. We suggest that the SMB is highly influenced by interactions between the large-scale surface topography of ice divides and the wind field of strong-wind events that are often associated with high-precipitation events. Local variations in the SMB are governed by the local surface topography, which is influenced by the bedrock topography. In the eastern part of DML, the accumulation rate in the second half of the 20th century is found to be higher by similar to 15% than averages over longer periods of 722 a or 7.9 ka before AD 2008. A similar increasing trend has been reported for many inland plateau sites in Antarctica with the exception of several sites on the leeward side of the ice divides.
|
|
| 16. |
|
|
| 17. |
- Furukawa, Toshi A., et al.
(författare)
-
Dismantling, optimising, and personalising internet cognitive behavioural therapy for depression : a systematic review and component network meta-analysis using individual data
- 2021
-
Ingår i: Lancet psychiatry. - London, United Kingdom : Elsevier. - 2215-0374 .- 2215-0366. ; 8:6, s. 500-511
-
Forskningsöversikt (refereegranskat)abstract
- Findings We identified 76 RCTs, including 48 trials contributing individual participant data (11 704 participants) and 28 trials with aggregate data (6474 participants). The participants' weighted mean age was 42.0 years and 12 406 (71%) of 17 521 reported were women. There was suggestive evidence that behavioural activation might be beneficial (iMD -1.83 [95% credible interval (CrI) -2.90 to -0.80]) and that relaxation might be harmful (1.20 [95% CrI 0.17 to 2.27]). Baseline severity emerged as the strongest prognostic factor for endpoint depression. Combining human and automated encouragement reduced dropouts from treatment (incremental odds ratio, 0.32 [95% CrI 0.13 to 0.93]). The risk of bias was low for the randomisation process, missing outcome data, or selection of reported results in most of the included studies, uncertain for deviation from intended interventions, and high for measurement of outcomes. There was moderate to high heterogeneity among the studies and their components. 511
|
|
| 18. |
- Furukawa, T., et al.
(författare)
-
Cooling dynamics of photo-excited negative carbon cluster ions stored in an ion storage ring
- 2015
-
Ingår i: Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms. - : Elsevier BV. - 0168-583X. ; 354, s. 192-196
-
Tidskriftsartikel (refereegranskat)abstract
- A newly found fast radiative cooling process of C-6(-) is studied by simulation based on statistical sharing of the internal energy by the vibrational modes both in the electronic ground and excited states. For comparison, a contrasting slow cooling of C6H- is simulated by the same procedure. The simulation demonstrates a distinct difference in the time evolution of energy distributions between C-6(-) and C6H-, and well reproduces the observed fast cooling of C-6(-) by recurrent electronic transitions and the slow cooling of C6H- by vibrational de-excitation. (C) 2014 Elsevier B.V. All rights reserved.
|
|
| 19. |
- Iida, S., et al.
(författare)
-
Rotationally Resolved Excitation Spectra Measured by Slow Electron Detachment from Si-2(-)
- 2020
-
Ingår i: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 11:13, s. 5199-5203
-
Tidskriftsartikel (refereegranskat)abstract
- Laser-induced delayed electron detachment from Si-2(-) stored in an electrostatic ion storage ring was observed on the 10 microsecond time scale. The excitation spectra for photon energies near threshold show well-resolved multipeak structures, which are attributed to rovibronic transitions to the electronic excited state. This structure appears only in the signal measured with the delay. The occurrence of delayed detachment on such a long time scale is unusual for diatomic molecules, suggesting that both the autodetachment and fluorescence are slow.
|
|
| 20. |
- Kono, Naoko, et al.
(författare)
-
Electronic and vibrational radiative cooling of the small carbon clusters C4− and C6−
- 2018
-
Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947. ; 98:6
-
Tidskriftsartikel (refereegranskat)abstract
- Delayed electron detachment yields of C4− and C6− induced by photoexcitation in an electrostatic ion storage ring were measured as functions of excitation energies and laser firing times, allowing for a mapping of their radiative cooling in a wide energy range. The energy window concept and discrimination of one- and twophoton absorption are critical in understanding the obtained results. The experimentally obtained electronic and vibrational cooling rates were consistent with a simulation based on detailed-balance theory. The even-odd alternation of vibrational cooling rates, predicted from IR intensities, was also examined. We found that the larger anion cools faster, with no indication of an even-odd alternation.
|
|
| 21. |
- Kono, N., et al.
(författare)
-
Inverse internal conversion in C4- below the electron detachment threshold
- 2015
-
Ingår i: Physical Chemistry Chemical Physics - PCCP. - : Royal Society of Chemistry (RSC). - 1463-9076 .- 1463-9084. ; 17:38, s. 24732-24737
-
Tidskriftsartikel (refereegranskat)abstract
- Inverse internal conversion followed by recurrent fluorescence was observed as a fast decay (10 μs range) in the time profile of neutral yields from photo-excited C4- molecular ions. We also elucidated the contribution of such electronic radiative cooling to the C4- ions with internal energy far below the detachment threshold by an alternative novel approach, observing the laser wavelength and storage time dependence (ms range) of the total yield of the photo-induced neutrals.
|
|
| 22. |
- Shiromaru, H., et al.
(författare)
-
Cooling dynamics of carbon cluster anions
- 2015
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635
-
Tidskriftsartikel (refereegranskat)abstract
- A series of ion storage experiments on small carbon cluster anions was conducted to understand size-dependent cooling processes. The laser-induced delayed electron detachment time profile show clear even/odd alternation due to the presence of the electronic cooling. The time evolution of the internal energy distribution was simulated for Cn- (n=4 to 7) with a common procedure taking vibrational and electronic cooling into account.
|
|
| 23. |
- Suzuki, R., et al.
(författare)
-
Vibrational radiative cooling of isolated C4- and C6-
- 2017
-
Ingår i: Journal of Physics: Conference Series. XXX International Conference on Photonic, Electronic, and Atomic Collisions (ICPEAC2017) 26 July to 1 August 2017, Cairns, Australia. - : IOP Publishing. - 1742-6588 .- 1742-6596.
-
Konferensbidrag (refereegranskat)abstract
- We have observed the storage-time dependence of the laser-induced electron detachment yields for the linear carbon cluster anions C4- and C6− stored in an electrostatic ion storage ring (TMU E-ring) with several laser wavelengths. The electron detachment yield reflects the decrease of the internal energy of the stored ions. We succeeded in obtaining the time evolution of the excitation energy distribution below the first dipole-allowed electronic excited energy Eex for C4- and C6−, which was well consistent to the behavior explained by vibrational IR-radiative cooling.
|
|
| 24. |
|
|
| 25. |
- Thinh, N.Q., et al.
(författare)
-
Properties of Ga-interstitial defects in AlxGa 1-xNyP1-y
- 2005
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 71:12
-
Tidskriftsartikel (refereegranskat)abstract
- A detailed account of the experimental results from optically detected magnetic resonance (ODMR) studies of grown-in defects in (Al)GaNP alloys, prepared by molecular beam epitaxy, is presented. The experimental procedure and an in-depth analysis by a spin Hamiltonian lead to the identification of two Gai defects (Gai-A and Gai-B). New information on the electronic properties of these defects and the recombination processes leading to the observation of the ODMR signals will be provided. These defects are deep-level defects. In conditions when the defect is directly involved in radiative recombination of the near-infrared photoluminescence band, the energy level of the Gai-B defect was estimated to be deeper than ~1.2 eV from either the conduction or valence band edge. In most cases, however, these defects act as nonradiative recombination centers, reducing the efficiency of light emission from the alloys. They can thus undermine the performance of potential photonic devices. High thermal stability is observed for these defects. ©2005 The American Physical Society.
|
|
| 26. |
- Yoshida, M., et al.
(författare)
-
Detection of recurrent fluorescence photons emitted from C4
- 2017
-
Ingår i: International conference on photonic electronic and atomic collisions 2017, 26 jul - 1 aug, Queensland, Australia. Journal of Physics, Conference Series 875:102016. - : IOP Publishing. - 1742-6588 .- 1742-6596.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We detected recurrent fluorescence photons from vibrationally hot C4- ions stored in an electrostatic ion storage ring. By virtue of the mass-independent storage condition, various anions produced in the laser ablation ion source were simultaneously stored with their own velocities, and ionic species emitting photons were identified from the temporal profile of the detected photons. The fluorescence synchronized with revolution of C4- , through the bandpass filter for the known absorption band, were clearly observed.
|
|
| 27. |
- Boström, Hanna L. B., et al.
(författare)
-
How Reproducible is the Synthesis of Zr-Porphyrin Metal-Organic Frameworks? An Interlaboratory Study
- 2024
-
Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 36:15
-
Tidskriftsartikel (refereegranskat)abstract
- Metal-organic frameworks (MOFs) are a rapidly growing class of materials that offer great promise in various applications. However, the synthesis remains challenging: for example, a range of crystal structures can often be accessed from the same building blocks, which complicates the phase selectivity. Likewise, the high sensitivity to slight changes in synthesis conditions may cause reproducibility issues. This is crucial, as it hampers the research and commercialization of affected MOFs. Here, it presents the first-ever interlaboratory study of the synthetic reproducibility of two Zr-porphyrin MOFs, PCN-222 and PCN-224, to investigate the scope of this problem. For PCN-222, only one sample out of ten was phase pure and of the correct symmetry, while for PCN-224, three are phase pure, although none of these show the spatial linker order characteristic of PCN-224. Instead, these samples resemble dPCN-224 (disordered PCN-224), which has recently been reported. The variability in thermal behavior, defect content, and surface area of the synthesised samples are also studied. The results have important ramifications for field of metal-organic frameworks and their crystallization, by highlighting the synthetic challenges associated with a multi-variable synthesis space and flat energy landscapes characteristic of MOFs. It performed an interlaboratory study of the synthesis of the metal-organic frameworks (MOFs) PCN-222 and PCN-224. Ten participants independently synthesized the two MOFs and the products are analyzed, primarily by X-ray diffraction. The success rates are low (one-three samples corresponding to a pure sample of the correct phase), thus highlighting the problems with irreproducibility in MOF synthesis. image
|
|
| 28. |
- Cameron, A. S., et al.
(författare)
-
Probing superconducting order in overdoped Cax Y1-xBa2Cu3 O7 by neutron diffraction measurements of the vortex lattice
- 2023
-
Ingår i: Physical Review B. - 2469-9950. ; 108:14
-
Tidskriftsartikel (refereegranskat)abstract
- We present small-Angle neutron scattering studies of the magnetic vortex lattice (VL) in Ca0.04Y0.96Ba2Cu3O7 up to a field of 16.7 T and Ca0.15Y0.85Ba2Cu3O7 up to 25 T to investigate the general behavior of the superconducting gap in YBCO-based compounds at high magnetic field. We find in these overdoped compounds that the series of VL structure transitions have shifted down in field relative to those reported for the undoped compound. The hole doping by calcium is expected to alter the Fermi velocity and it reduces the upper critical field of the system. However, we attribute the VL changes mainly to the weakening of the 1D superconductivity in the Cu-O chains by the disorder introduced by doping. The high-field structure of the VL is similar to recent measurements on the parent compound in even higher fields of 25 T, which indicates that the fundamental d-wave nature of the superconducting gap is unchanged by calcium doping. This is corroborated by the temperature dependence of the VL form factor, which also shows the same d-wave behavior as observed in other cuprates. We also argue that they might be the explanation of Pauli paramagnetic effects in the field dependence of the VL form factor.
|
|
| 29. |
- Chen, Fuqiang, et al.
(författare)
-
Radiative cooling of cationic carbon clusters, CN+, N=8,10,13-16
- 2019
-
Ingår i: Physical Chemistry Chemical Physics - PCCP. - : Royal Society of Chemistry (RSC). - 1463-9076 .- 1463-9084. ; 21, s. 1587-1596
-
Tidskriftsartikel (refereegranskat)abstract
- The radiative cooling of highly excited carbon cluster cations of sizes N = 8, 10, 13–16 has been studied in an electrostatic storage ring. The cooling rate constants vary with cluster size from a maximum at N = 8 of 2.6 × 104 s−1 and a minimum at N = 13 of 4.4 × 103 s−1. The high rates indicate that photon emission takes place from electronically excited ions, providing a strong stabilizing cooling of the molecules.
|
|
| 30. |
|
|
| 31. |
- Dagnelund, Daniel, 1980-, et al.
(författare)
-
Effect of growth conditions on grown-in defect formation and luminescence efficiency in GaInNP epilayers grown by molecular-beam epitaxy.
- 2008
-
Ingår i: Physica status solidi (c)Special Issue: E-MRS 2007 Spring Meeting – Symposium F and Conference on Photonic Materials. - Weinheim : Wiley-VCH Verlagsgesellschaft. ; , s. 460-463
-
Konferensbidrag (refereegranskat)abstract
- A detailed study of the impact of different growth conditions (i.e. ion bombardment, nitrogen flow and In content) on the defect formation in Ga(In)NP epilayers grown on GaP substrates by solid-source molecular beam epitaxy is performed. Reduced nitrogen ion bombardment during the growth is shown to significantly reduce formation of defects acting as competing recombination centers, such as a Ga interstitial defect and other unidentified defects revealed by optically detected magnetic resonance. Further, high nitrogen flow is found to be even more effective than the ion bombardment in introducing the defects. The incorporation of In by 5.1% is, on the other hand, found not to affect the introduction of defects. The results provide a useful insight into the formation mechanism of the defects that will hopefully shed light on a control of the defect introduction in the alloys by optimizing growth conditions.
|
|
| 32. |
|
|
| 33. |
- Dagnelund, Daniel, 1980-, et al.
(författare)
-
Effect of nitrogen ion bombardment on defect formation and luminescence efficiency of GaNP epilayers grown by molecular-beam epitaxy
- 2006
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 88:10, s. 101904-
-
Tidskriftsartikel (refereegranskat)abstract
- Radiative efficiency of GaNP epilayers grown on GaP substrates by solid-source molecular beam epitaxy is significantly improved by reduced nitrogen ion bombardment during the growth. Based on the results of temperature-dependent photoluminescence (PL) and optically detected magnetic resonance studies (ODMR), the observed improvements are attributed to reduced formation of defects, such as a Ga interstitial related defect and an unidentified defect revealed by ODMR. We demonstrate that these defects act as competing recombination centers, which promote thermal quenching of the PL intensity and result in a substantial (34×) decrease in room-temperature PL intensity. © 2006 American Institute of Physics.
|
|
| 34. |
- Dagnelund, Daniel, 1980-, et al.
(författare)
-
Evidence for a phosphorus-related interfacial defect complex at a GaP/GaNP heterojunction
- 2010
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - : The American Physical Society. - 1098-0121 .- 1550-235X. ; 81, s. 115334-
-
Tidskriftsartikel (refereegranskat)abstract
- Optically detected magnetic resonance (ODMR) studies of molecular beam epitaxial GaNP/GaP structures reveal presence of a P-related complex defect, evident from its resolved hyperfine interaction between an unpaired electronic spin (S=1/2) and a nuclear spin (I = ½) of a 31P atom. The principal axis of the defect is concluded to be along a <111> crystallographic direction from angular dependence of the ODMR spectrum, restricting the P atom (either a PGa antisite or a Pi interstitial) and its partner in the complex defect to be oriented along this direction. The principal values of the electronic g-tensor and hyperfine interaction tensor are determined as: g┴=2.013, g║=2.002, and A┴=130´10-4 cm-1, A║=330´10-4 cm-1, respectively. The interface nature of the defect is clearly manifested by the absence of the ODMR lines originating from two out of four equivalent <111> orientations. Defect formation is shown to be facilitated by nitrogen ion bombardment under non-equilibrium growth conditions and the defect is thermally stable upon post-growth thermal annealing.
|
|
| 35. |
- Dagnelund, Daniel, 1980-, et al.
(författare)
-
Formation of grown-in defects in molecular beam epitaxial Ga(In)NP : effects of growth conditions and post-growth treatments
- 2008
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 103, s. 063519-
-
Tidskriftsartikel (refereegranskat)abstract
- Effects of growth conditions and post-growth treatments, such as presence of N ions, N2 flow, growth temperature, In alloying, and postgrowth rapid thermal annealing (RTA), on formation of grown-in defects in Ga(In)NP prepared by molecular beam epitaxy are studied in detail by the optically detected magnetic resonance (ODMR) technique. Several common residual defects, such as two Ga-interstitial defects (i.e., Gai-A and Gai-B) and two unidentified defects with a g factor around 2 (denoted by S1 and S2), are closely monitored. Bombardment of impinging N ions on grown sample surface is found to facilitate formation of these defects. Higher N2 flow is shown to have an even more profound effect than a higher number of ions in introducing these defects. Incorporation of a small amount of In (e.g., 5.1%) in GaNP seems to play a minor role in the formation of the defects. In GaInNP with 45% of In; however, the defects were found to be abundant. Effect of RTA on the defects is found to depend on initial configurations of Gai-related defects formed during the growth. In the alloys where the Gai-A and Gai-B defects are absent in the as-grown samples (i.e., GaNP grown at a low temperature of 460 °C), the concentrations of the two Gai defects are found to increase after postgrowth RTA. This indicates that the defects originally introduced in the as-grown alloys have been transformed into the more thermally stable Gai-A and Gai-B during RTA. On the other hand, when the Gai-A and Gai-B are readily abundant (e.g., at higher growth temperatures (>=500 °C), RTA leads to a slight reduction of the Gai-A and Gai-B ODMR signals. The S2 defect is also shown to be thermally stable upon the RTA treatment.
|
|
| 36. |
- Dagnelund, Daniel, et al.
(författare)
-
Phosphorus-related interfacial defect complex at a GaP/GaNP heterojunction
- 2010
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- For full exploration of dilute nitrides in device applications, a better understanding and control of defects located at interfaces involving e.g. Ga(In)NP are required. In this work we report on the first identification of a point defect situated at an interface between two semiconductors: GaNP and GaP. The defect is concluded to be a complex involving a P antisite or a P interstitial in its core, partnered with a neighboring impurity/defect aligned along a <111> direction, from detailed angular dependence studies of the optically detected magnetic resonance (ODMR) spectra at both X- and Q-band microwave frequencies. The principal g and A values, g┴=2.013, g║=2.002, A┴=130x10-4 cm-1 and A║=330x10-4 cm-1, are obtained from a spin Hamiltonian analysis. The interface nature of the defect is clearly evident from the absence of the ODMR lines originating from two out of four equivalent <111> orientations. Defect formation is shown to be facilitated by severe nitrogen ion bombardment under non-equilibrium growth conditions during solid-source molecular beam epitaxy and the defect is thermally stable upon post-growth thermal annealing.
|
|
| 37. |
- Dagnelund, Daniel, 1980-, et al.
(författare)
-
Spin resonance spectroscopy of grown-in defects in Ga(In)NP alloys
- 2008
-
Ingår i: 7th International Conference on Physics of Light-Matter Coupling in Nanostructures, 2007. - : Elsevier Ltd.. ; , s. 620-625
-
Konferensbidrag (refereegranskat)abstract
- We employ the optically detected magnetic resonance (ODMR) technique to study and identify important grown-in defects in Ga(In)NP grown by molecular-beam epitaxy (MBE). Several types of defects were revealed from ODMR studies. The dominant defects were found to be related to Ga interstitials, evident form their characteristic hyperfine interaction arising from the spin interaction between the electron and the Ga nucleus. Some other as yet unidentified intrinsic defects were also found to be commonly present in the alloys. The effects of growth conditions (ion bombardment, N2 gas flow, etc.) and post-growth rapid thermal annealing on the formation of these defects were studied in detail, shedding light on the formation mechanism of defects.
|
|
| 38. |
- Eriksson, Tobias A., et al.
(författare)
-
Digital self-coherent continuous variable quantum key distribution system
- 2020
-
Ingår i: Optics InfoBase Conference Papers. - : Optica Publishing Group.
-
Konferensbidrag (refereegranskat)abstract
- We investigate a continuous variable quantum key distribution system with digital tracking of both polarization and phase. Stable operation over 25km for 36 hours with secret key rates between 1.9 and 2.8 Mbit/s is demonstrated.
|
|
| 39. |
|
|
| 40. |
|
|
| 41. |
|
|
| 42. |
- Hu, W., et al.
(författare)
-
Electron transport in self-assembled polymer molecular junctions
- 2006
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 96:2, s. 027801-
-
Tidskriftsartikel (refereegranskat)abstract
- A molecular junction of a poly(p-phenyleneethynylene)s derivative with thioacetate end groups (TA-PPE) was fabricated by self-assembling. Nanogap electrodes made by electroplating technique was used to couple thiol end groups of TA-PPE molecules. Room temperature current-voltage characteristics of the molecular junction exhibited highly periodic, repeatable, and identical stepwise features. First-principles calculations suggest that one possibility for the equidistant step is due to the opening of different conducting channels that corresponds to the unoccupied molecular orbitals of the polymer in the junction. It is interesting to see that an 18 nm long polymer is of quantized electronic structures and behaves like a quantum transport device.
|
|
| 43. |
- Izadifard, Morteza, 1965-, et al.
(författare)
-
Effects of rapid thermal annealing on optical properties of GaNxP1−x alloys grown by solid source molecular beam epitaxy
- 2005
-
Ingår i: Semiconductor Science and Technology. - : IOP Publishing. - 0268-1242 .- 1361-6641. ; 20:5, s. 353-356
-
Tidskriftsartikel (refereegranskat)abstract
- Temperature-dependent photoluminescence (PL), PL excitation and time-resolved PL measurements were employed to study the effects of rapid thermal annealing (RTA) on optical properties of GaNxP1−x alloys grown by solid source molecular beam epitaxy. A substantial increase in radiative efficiency of GaNP epilayers, which is especially pronounced for the high-energy PL component, was achieved after RTA and is attributed to annealing out of competing non-radiative centres. The latter is evident from reduced quenching of the PL intensity with increasing measurement temperature, which results in a strong increase (up to 18 times) in the PL intensity at room temperature (RT), as well as from a substantial increase in carrier lifetime at RT deduced from time-resolved PL measurements.
|
|
| 44. |
- Izadifard, Morteza, 1965-, et al.
(författare)
-
Effects of rapid thermal annealing on optical quality of GaNP alloys
- 2004
-
Ingår i: EMRS-2004 Spring Meeting,2004. - : Institution of Engineering and Technology (IET). ; , s. 335-
-
Konferensbidrag (refereegranskat)abstract
- Significant improvements in radiative efficiency of GaNP epilayers grown on GaP substrates by solid-source molecular beam epitaxy (MBE) are achieved by post-growth rapid thermal annealing (RTA). From temperature-dependent CW and time-resolved photoluminescence (PL) spectroscopies combined with PL excitation measurements, the observed improvements are attributed to annealing out of competing nonradiative centres. This conclusion is supported by the following experimental evidence: reduced thermal quenching of the PL intensity resulting in a substantial (up to 18 times) increase at room temperature (RT) after RTA, and simultaneous improvements in carrier lifetime at RT deduced from time-resolved PL measurements.
|
|
| 45. |
- Izadifard, Morteza, 1965-, et al.
(författare)
-
Evaluation of optical quality and defect properties of GaNxP1−x alloys lattice matched to Si
- 2004
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 85, s. 6347-
-
Tidskriftsartikel (refereegranskat)abstract
- By using a variety of optical characterization techniques, including cathodoluminescence, temperature-dependent cw- and time-resolved photoluminescence (PL), and PL excitation spectroscopies, high optical quality of the GaN0.018P0.982 epilayers lattice matched to Si substrates is demonstrated and is shown to be comparable to that of the “state-of-the-art” GaNP alloys grown on GaP substrates. The growth of GaNP on Si is, however, found to facilitate the formation of several point defects, including complexes involving Ga interstitial atoms (Gai).
|
|
| 46. |
|
|
| 47. |
- Karyotaki, Eirini, et al.
(författare)
-
Internet-Based Cognitive Behavioral Therapy for Depression : A Systematic Review and Individual Patient Data Network Meta-analysis
- 2021
-
Ingår i: JAMA psychiatry. - : American Medical Association. - 2168-6238 .- 2168-622X. ; 78:4, s. 361-371
-
Forskningsöversikt (refereegranskat)abstract
- IMPORTANCE: Personalized treatment choices would increase the effectiveness of internet-based cognitive behavioral therapy (iCBT) for depression to the extent that patients differ in interventions that better suit them.OBJECTIVE: To provide personalized estimates of short-term and long-term relative efficacy of guided and unguided iCBT for depression using patient-level information.DATA SOURCES: We searched PubMed, Embase, PsycInfo, and Cochrane Library to identify randomized clinical trials (RCTs) published up to January 1, 2019.STUDY SELECTION: Eligible RCTs were those comparing guided or unguided iCBT against each other or against any control intervention in individuals with depression. Available individual patient data (IPD) was collected from all eligible studies. Depression symptom severity was assessed after treatment, 6 months, and 12 months after randomization.DATA EXTRACTION AND SYNTHESIS: We conducted a systematic review and IPD network meta-analysis and estimated relative treatment effect sizes across different patient characteristics through IPD network meta-regression.MAIN OUTCOMES AND MEASURES: Patient Health Questionnaire-9 (PHQ-9) scores.RESULTS: Of 42 eligible RCTs, 39 studies comprising 9751 participants with depression contributed IPD to the IPD network meta-analysis, of which 8107 IPD were synthesized. Overall, both guided and unguided iCBT were associated with more effectiveness as measured by PHQ-9 scores than control treatments over the short term and the long term. Guided iCBT was associated with more effectiveness than unguided iCBT (mean difference [MD] in posttreatment PHQ-9 scores, -0.8; 95% CI, -1.4 to -0.2), but we found no evidence of a difference at 6 or 12 months following randomization. Baseline depression was found to be the most important modifier of the relative association for efficacy of guided vs unguided iCBT. Differences between unguided and guided iCBT in people with baseline symptoms of subthreshold depression (PHQ-9 scores 5-9) were small, while guided iCBT was associated with overall better outcomes in patients with baseline PHQ-9 greater than 9.CONCLUSIONS AND RELEVANCE: In this network meta-analysis with IPD, guided iCBT was associated with more effectiveness than unguided iCBT for individuals with depression, benefits were more substantial in individuals with moderate to severe depression. Unguided iCBT was associated with similar effectiveness among individuals with symptoms of mild/subthreshold depression. Personalized treatment selection is entirely possible and necessary to ensure the best allocation of treatment resources for depression.
|
|
| 48. |
- Kaur, H., et al.
(författare)
-
Differential Role of HAMP-like Linkers in Regulating the Functionality of the Group III Histidine Kinase DhNik1p
- 2014
-
Ingår i: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 289:29, s. 20245-20258
-
Tidskriftsartikel (refereegranskat)abstract
- Nik1 orthologs are sensor kinases that function upstream of the high osmolarity glycerol/p38 MAPK pathway in fungi. They contain a poly-HAMP module at their N terminus, which plays a pivotal role in osmosensing as well as fungal death upon exposure to fludioxonil. DhNik1p is a typical member of this class that contains five HAMP domains and four HAMP-like linkers. We investigated the contribution of each of the HAMP-like linker regions to the functionality of DhNik1p and found that the HAMP4b linker was essential as its deletion resulted in the complete loss of activity. Replacement of this linker with flexible peptide sequences did not restore DhNik1p activity. Thus, the HAMP-like sequence and possibly structural features of this linker region are indispensable for the kinase activity of DhNik1p. To gain insight into the global shape of the poly-HAMP module in DhNik1p (HAMP1-5), multi-angle laser light and small angle x-ray scattering studies were carried out. Those data demonstrate that the maltose-binding protein-tagged HAMP1-5 protein exist as a dimer in solution with an elongated shape of maximum linear dimension similar to 365 angstrom. Placement of a sequence similarity based model of the HAMP1-5 protein inside experimental data-based models showed how two chains of HAMP1-5 are entwined on each other and the overall structure retained a periodicity. Normal mode analysis of the structural model is consistent with the H4b linker being a key to native-like collective motion in the protein. Overall, our shape-function studies reveal how different elements in the HAMP1-5 structure mediate its function.
|
|
| 49. |
- Luis, R. S., et al.
(författare)
-
Demonstration of a 1 Pb/s spatial channel network node
- 2019
-
Ingår i: IET Conference Publications. - : Institution of Engineering and Technology.
-
Konferensbidrag (refereegranskat)abstract
- We experimentally demonstrate a petabit-class hierarchical SDM switching node with granularity from 10 Tb/s to 1 Pb/s. We address spatial bypassing network scenarios, optical channel grooming, spatial multiplex section protection switching, and optical channels using coupled and uncoupled spatial channels.
|
|
| 50. |
|
|
