| 1. |
|
|
| 2. |
- Aad, G, et al.
(författare)
-
- 2015
-
swepub:Mat__t
|
|
| 3. |
- Aaltonen, T., et al.
(författare)
-
Combination of Tevatron Searches for the Standard Model Higgs Boson in the W+W- Decay Mode
- 2010
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 104:6, s. 061802-
-
Tidskriftsartikel (refereegranskat)abstract
- We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W+W-. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb(-1) of p (p) over bar collisions at root s = 1.96 TeV at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard model Higgs boson in the mass range 162-166 GeV at the 95% C.L.
|
|
| 4. |
- Ruilope, LM, et al.
(författare)
-
Design and Baseline Characteristics of the Finerenone in Reducing Cardiovascular Mortality and Morbidity in Diabetic Kidney Disease Trial
- 2019
-
Ingår i: American journal of nephrology. - : S. Karger AG. - 1421-9670 .- 0250-8095. ; 50:5, s. 345-356
-
Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background:</i></b> Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. <b><i>Patients and</i></b> <b><i>Methods:</i></b> The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate ≥25 mL/min/1.73 m<sup>2</sup> and albuminuria (urinary albumin-to-creatinine ratio ≥30 to ≤5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level α = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. <b><i>Conclusions:</i></b> FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049.
|
|
| 5. |
- Khatri, C, et al.
(författare)
-
Outcomes after perioperative SARS-CoV-2 infection in patients with proximal femoral fractures: an international cohort study
- 2021
-
Ingår i: BMJ open. - : BMJ. - 2044-6055. ; 11:11, s. e050830-
-
Tidskriftsartikel (refereegranskat)abstract
- Studies have demonstrated high rates of mortality in people with proximal femoral fracture and SARS-CoV-2, but there is limited published data on the factors that influence mortality for clinicians to make informed treatment decisions. This study aims to report the 30-day mortality associated with perioperative infection of patients undergoing surgery for proximal femoral fractures and to examine the factors that influence mortality in a multivariate analysis.SettingProspective, international, multicentre, observational cohort study.ParticipantsPatients undergoing any operation for a proximal femoral fracture from 1 February to 30 April 2020 and with perioperative SARS-CoV-2 infection (either 7 days prior or 30-day postoperative).Primary outcome30-day mortality. Multivariate modelling was performed to identify factors associated with 30-day mortality.ResultsThis study reports included 1063 patients from 174 hospitals in 19 countries. Overall 30-day mortality was 29.4% (313/1063). In an adjusted model, 30-day mortality was associated with male gender (OR 2.29, 95% CI 1.68 to 3.13, p<0.001), age >80 years (OR 1.60, 95% CI 1.1 to 2.31, p=0.013), preoperative diagnosis of dementia (OR 1.57, 95% CI 1.15 to 2.16, p=0.005), kidney disease (OR 1.73, 95% CI 1.18 to 2.55, p=0.005) and congestive heart failure (OR 1.62, 95% CI 1.06 to 2.48, p=0.025). Mortality at 30 days was lower in patients with a preoperative diagnosis of SARS-CoV-2 (OR 0.6, 95% CI 0.6 (0.42 to 0.85), p=0.004). There was no difference in mortality in patients with an increase to delay in surgery (p=0.220) or type of anaesthetic given (p=0.787).ConclusionsPatients undergoing surgery for a proximal femoral fracture with a perioperative infection of SARS-CoV-2 have a high rate of mortality. This study would support the need for providing these patients with individualised medical and anaesthetic care, including medical optimisation before theatre. Careful preoperative counselling is needed for those with a proximal femoral fracture and SARS-CoV-2, especially those in the highest risk groups.Trial registration numberNCT04323644
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Grieser, M., et al.
(författare)
-
Storage ring at HIE-ISOLDE
- 2012
-
Ingår i: European Physical Journal: Special Topics. - : Springer Science and Business Media LLC. - 1951-6401 .- 1951-6355. ; 207:1, s. 1-117
-
Tidskriftsartikel (refereegranskat)abstract
- We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams that is unique in the world. The envisaged physics programme is rich and varied, spanning from investigations of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. The TSR might also be employed for removal of isobaric contaminants from stored ion beams and for systematic studies within the neutrino beam programme. In addition to experiments performed using beams recirculating within the ring, cooled beams can also be extracted and exploited by external spectrometers for high-precision measurements. The existing TSR, which is presently in operation at the Max-Planck Institute for Nuclear Physics in Heidelberg, is well-suited and can be employed for this purpose. The physics cases as well as technical details of the existing ring facility and of the beam and infrastructure requirements at HIE-ISOLDE are discussed in the present technical design report.
|
|
| 9. |
- Grieser, M., et al.
(författare)
-
Storage ring at HIE-ISOLDE Technical design report
- 2012
-
Ingår i: The European Physical Journal Special Topics. - : Springer Science and Business Media LLC. - 1951-6355 .- 1951-6401. ; 207:1, s. 1-117
-
Forskningsöversikt (refereegranskat)abstract
- We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams that is unique in the world. The envisaged physics programme is rich and varied, spanning from investigations of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. The TSR might also be employed for removal of isobaric contaminants from stored ion beams and for systematic studies within the neutrino beam programme. In addition to experiments performed using beams recirculating within the ring, cooled beams can also be extracted and exploited by external spectrometers for high-precision measurements. The existing TSR, which is presently in operation at the Max-Planck Institute for Nuclear Physics in Heidelberg, is well-suited and can be employed for this purpose. The physics cases as well as technical details of the existing ring facility and of the beam and infrastructure requirements at HIE-ISOLDE are discussed in the present technical design report.
|
|
| 10. |
|
|
| 11. |
|
|
| 12. |
|
|
| 13. |
- Xie, Z., et al.
(författare)
-
Physiological responses to salinity change and diel-cycling hypoxia in gills of Hong Kong oyster Crassostrea hongkongensis
- 2023
-
Ingår i: Aquaculture. - : Elsevier BV. - 0044-8486. ; 570
-
Tidskriftsartikel (refereegranskat)abstract
- Global climate change is a frequent cause of salinity fluctuation in seawater, especially in aquaculture sites. Moreover, anthropologic activities often cause seawater eutrophication with the consequence that hypoxia ap-pears often during nighttime. The Hong Kong oyster Crassostrea hongkongensis, as a species that inhabits estuarine and coastal waters, is faced with such challenges. In this study, oyster physiological changes were considered to be closely related to hypoxia and salinity changes. Physiological indices were examined in Hong Kong oysters by employing six treatments to shed light into the effects of diel-cycling hypoxia (periodical hypoxia) and salinity change. Three salinities (10%o, low salinity; 25%o, normal salinity; and 35%o, high salinity) and two types of dissolved oxygen (normoxia, 6 mg/L throughout the day) and periodical hypoxic condition (6 mg/L at daytime for 12 h and 2 mg/L at nighttime for 12 h) were set. After 14-and 28-day exposures, gill tissues were sampled to detect changes in gill ATP production, mitochondrial membrane potential (MMP), mitochondrial reactive oxygen species production (ROS), and gill respiratory metabolic enzymes. Results indicated that periodical hypoxia and salinity change led to increased hexokinase (HK) and pyruvate kinase (PK) (p < 0.05). By contrast, they had no significant effect on mitochondrial number (MN). Adenosine-triphosphate (ATP) production only increased in the early exposure. In addition, low salinity with periodical hypoxia resulted in decreased MMP, lactate dehy-drogenase (LDH), and succinate dehydrogenase (SDH, p < 0.05). On the contrary, periodical hypoxia with high salinity led to increases in ATP and ROS and decreases in SDH, MMP, and LDH (p < 0.05). These results revealed that when diel-cycling hypoxia occurs with salinity change, the gill metabolism of Hong Kong oysters are gradually dominated by glycolysis while aerobic respiration decreases. Moreover, gill functions could be affected although energy accumulation exists during early exposure. Therefore, long-term exposure to periodical hypoxia with salinity change poses risk to the health and growth of Hong Kong oysters, impairing oyster aquaculture and coastal ecosystem health.
|
|
| 14. |
|
|
| 15. |
- Bruin, WB, et al.
(författare)
-
Structural neuroimaging biomarkers for obsessive-compulsive disorder in the ENIGMA-OCD consortium: medication matters
- 2020
-
Ingår i: Translational psychiatry. - : Springer Science and Business Media LLC. - 2158-3188. ; 10:1, s. 342-
-
Tidskriftsartikel (refereegranskat)abstract
- No diagnostic biomarkers are available for obsessive-compulsive disorder (OCD). Here, we aimed to identify magnetic resonance imaging (MRI) biomarkers for OCD, using 46 data sets with 2304 OCD patients and 2068 healthy controls from the ENIGMA consortium. We performed machine learning analysis of regional measures of cortical thickness, surface area and subcortical volume and tested classification performance using cross-validation. Classification performance for OCD vs. controls using the complete sample with different classifiers and cross-validation strategies was poor. When models were validated on data from other sites, model performance did not exceed chance-level. In contrast, fair classification performance was achieved when patients were grouped according to their medication status. These results indicate that medication use is associated with substantial differences in brain anatomy that are widely distributed, and indicate that clinical heterogeneity contributes to the poor performance of structural MRI as a disease marker.
|
|
| 16. |
- Guo, Y., et al.
(författare)
-
Hypercomplex Low Rank Reconstruction for NMR Spectroscopy
- 2023
-
Ingår i: Signal Processing. - : Elsevier BV. - 0165-1684. ; 203
-
Tidskriftsartikel (refereegranskat)abstract
- Nuclear magnetic resonance (NMR) spectroscopy serves as an important tool to analyze chemicals and proteins in bioengineering. Multi-dimensional NMR offers a major improvement in resolution with multi-dimensional spectrum, but significantly increases data acquisition time and produces hypercomplex data that is difficult to be handled. To reduce this time, non-uniformly sampling can be applied to obtain undersampled data and using a reconstruction approach, such as the state-of-the-art low rank method, to remove the spectral artifacts introduced by undersampling. However, only complex format of signal, including the real and imaginary parts, is considered in previous low rank approach, which is less efficient when dealing with hypercomplex data that has multiple components. To solve this problem, a hypercomplex low rank model is proposed by introducing an adjoint matrix operation and then solved with a fast matrix factorization algorithm. This method explores redundant information among all the components of hypercomplex signal. Using simulated data and real protein data, we demonstrate that the proposed method provides a fast and high-fidelity reconstruction of hypercomplex spectroscopy in fast NMR. © 2022 Elsevier B.V.
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
|
|
| 20. |
- Wang, Z., et al.
(författare)
-
A Sparse Model-Inspired Deep Thresholding Network for Exponential Signal Reconstruction--Application in Fast Biological Spectroscopy
- 2022
-
Ingår i: IEEE Transactions on Neural Networks and Learning Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 2162-237X .- 2162-2388. ; 34:10, s. 7578-92
-
Tidskriftsartikel (refereegranskat)abstract
- The nonuniform sampling (NUS) is a powerful approach to enable fast acquisition but requires sophisticated reconstruction algorithms. Faithful reconstruction from partially sampled exponentials is highly expected in general signal processing and many applications. Deep learning (DL) has shown astonishing potential in this field, but many existing problems, such as lack of robustness and explainability, greatly limit its applications. In this work, by combining the merits of the sparse model-based optimization method and data-driven DL, we propose a DL architecture for spectra reconstruction from undersampled data, called MoDern. It follows the iterative reconstruction in solving a sparse model to build the neural network, and we elaborately design a learnable soft-thresholding to adaptively eliminate the spectrum artifacts introduced by undersampling. Extensive results on both synthetic and biological data show that MoDern enables more robust, high-fidelity, and ultrafast reconstruction than the state-of-the-art methods. Remarkably, MoDern has a small number of network parameters and is trained on solely synthetic data while generalizing well to biological data in various scenarios. Furthermore, we extend it to an open-access and easy-to-use cloud computing platform (XCloud-MoDern), contributing a promising strategy for further development of biological applications.
|
|
| 21. |
- Ahmed, M., et al.
(författare)
-
Search for the lepton-family-number nonconserving decay μ +→e +γ
- 2002
-
Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 65:11
-
Tidskriftsartikel (refereegranskat)abstract
- The MEGA experiment, which searched for the muon- and electron-number violating decay μ +→e + γ, is described. The spectrometer system, the calibrations, the data taking procedures, the data analysis, and the sensitivity of the experiment are discussed. The most stringent upper limit on the branching ratio, B(μ + →e + γ)<1.2×10 -11 with 90% confidence, is derived from a likelihood analysis.
|
|
| 22. |
- Fu, Y., et al.
(författare)
-
Defect-Assisted Loading and Docking Conformations of Pharmaceuticals in Metal–Organic Frameworks
- 2021
-
Ingår i: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 60:14, s. 7719-7727
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding of drug–carrier interactions is essential for the design and application of metal–organic framework (MOF)-based drug-delivery systems, and such drug–carrier interactions can be fundamentally different for MOFs with or without defects. Herein, we reveal that the defects in MOFs play a key role in the loading of many pharmaceuticals with phosphate or phosphonate groups. The host–guest interaction is dominated by the Coulombic attraction between phosphate/phosphonate groups and defect sites, and it strongly enhances the loading capacity. For similar molecules without a phosphate/phosphonate group or for MOFs without defects, the loading capacity is greatly reduced. We employed solid-state NMR spectroscopy and molecular simulations to elucidate the drug–carrier interaction mechanisms. Through a synergistic combination of experimental and theoretical analyses, the docking conformations of pharmaceuticals at the defects were revealed.
|
|
| 23. |
|
|
| 24. |
- Lee, Roger, et al.
(författare)
-
Genetic studies on the functional relevance of the protein prenyltransferases in skin keratinocytes
- 2010
-
Ingår i: Oxford Journals About the Journal Human Molecular Genetics. - 0964-6906. ; 19:8, s. 1603-1617
-
Tidskriftsartikel (refereegranskat)abstract
- The modification of proteins with farnesyl or geranylgeranyl lipids, a process called protein prenylation, facilitates interactions of proteins with membrane surfaces. Protein prenylation is carried out by a pair of cytosolic enzymes, protein farnesyltransferase (FTase) and protein geranylgeranyltransferase type I (GGTase-I). FTase and GGTase-I have attracted interest as therapeutic targets for both cancer and progeria, but very little information exists on the importance of these enzymes for homeostasis of normal tissues. One study actually suggested that FTase is entirely dispensable. To explore the importance of the protein prenyltransferases for normal tissues, we used conditional knockout alleles for Fntb and Pggt1b (which encode the beta-subunits of FTase and GGTase-I, respectively) and a keratin 14-Cre transgene to create mice lacking FTase or GGTase-I in skin keratinocytes. Keratinocyte-specific Fntb knockout mice were viable but developed severe alopecia. Although hair follicles appeared normal during development, they were morphologically abnormal after birth, and ultrastructural and immunohistochemical studies revealed many apoptotic cells. The interfollicular epidermis of Fntb-deficient mice appeared normal; however, keratinocytes from these mice could not proliferate in culture. As expected, non-farnesylated prelamin A and non-farnesylated DNAJA1 accumulated in Fntb-deficient keratinocytes. Keratinocyte-specific Pggt1b knockout mice survived development but died shortly after birth. Like Fntb-deficient keratinocytes, Pggt1b-deficient keratinocytes did not proliferate in culture. Thus, both FTase and GGTase-I are required for the homeostasis of skin keratinocytes.
|
|
| 25. |
- Lestinsky, M., et al.
(författare)
-
Physics book: CRYRING@ESR
- 2016
-
Ingår i: European Physical Journal: Special Topics. - : Springer Science and Business Media LLC. - 1951-6401 .- 1951-6355. ; 225:5, s. 797-882
-
Forskningsöversikt (refereegranskat)abstract
- The exploration of the unique properties of stored and cooled beams of highly-charged ions as provided by heavy-ion storage rings has opened novel and fascinating research opportunities in the realm of atomic and nuclear physics research. Since the late 1980s, pioneering work has been performed at the CRYRING at Stockholm (Abrahamsson et al. 1993) and at the Test Storage Ring (TSR) at Heidelberg (Baumann et al. 1988). For the heaviest ions in the highest charge-states, a real quantum jump was achieved in the early 1990s by the commissioning of the Experimental Storage Ring (ESR) at GSI Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt (Franzke 1987) where challenging experiments on the electron dynamics in the strong field regime as well as nuclear physics studies on exotic nuclei and at the borderline to atomic physics were performed. Meanwhile also at Lanzhou a heavy-ion storage ring has been taken in operation, exploiting the unique research opportunities in particular for medium-heavy ions and exotic nuclei (Xia et al. 2002).
|
|
| 26. |
- Litvinov, Yu.A., et al.
(författare)
-
Nuclear physics experiments with ion storage rings
- 2013
-
Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - : Elsevier BV. - 0168-583X. ; 317:PART B, s. 603-616
-
Tidskriftsartikel (refereegranskat)abstract
- In the last two decades a number of nuclear structure and astrophysics experiments were performed at heavy-ion storage rings employing unique experimental conditions offered by such machines. Furthermore, building on the experience gained at the two facilities presently in operation, several new storage ring projects were launched worldwide. This contribution is intended to provide a brief review of the fast growing field of nuclear structure and astrophysics research at storage rings.
|
|
| 27. |
|
|
| 28. |
- Ng, E. Y. X., et al.
(författare)
-
Genome-wide SNPs confirm plumage polymorphism and hybridisation within a Cyornis flycatcher species complex
- 2022
-
Ingår i: Zoologica Scripta. - : Wiley. - 0300-3256 .- 1463-6409. ; 52:1, s. 1-16
-
Tidskriftsartikel (refereegranskat)abstract
- Morphology has been a leading taxonomic guiding light to systematists for the last couple of hundred years. However, the genetic and - more recently - genomic revolution have produced numerous demonstrations of erroneous classifications that were based on labile morphological traits. We used thousands of genome-wide markers to shed light on evolutionary dynamics in a confusing and taxonomically obscure group of Asian Cyornis flycatchers. Using genomic data, we corroborated recent findings based on three mitochrondrial and five nuclear genes that the two taxa hainanus and klossi which were previously treated as separate species (Cyornis hainanus and Cyornis rubeculoides klossi, respectively) are genomically homogeneous and form a single species, C. hainanus. We also uncovered a novel case of interbreeding between C. hainanus and a non-sister species, C. glaucicomans, illustrating these flycatchers' ability to hybridise in marginal situations even after substantial times of divergence. Our study illustrates how genome-wide loci can shed light on complicated taxonomic problems, resulting in a better integration of phenotypic and genotypic data.
|
|
| 29. |
|
|
| 30. |
- Szymanski, J. J., et al.
(författare)
-
A study of the decay mu –> e gamma by the MEGA experiment
- 1996
-
Ingår i: Proceedings, 9th Meeting, DPF'96, Minneapolis, USA, August 11-15, 1996. Vol. 1, 2.. ; , s. 1450-1452
-
Konferensbidrag (refereegranskat)
|
|
| 31. |
- Szymanski, J. J., et al.
(författare)
-
MEGA : A search for the decay mu –> e gamma
- 1994
-
Ingår i: Intersections between particle and nuclear physics. Proceedings, 5th Conference, St. Petersburg, USA, May 31-June 6, 1994. ; , s. 789-792
-
Konferensbidrag (refereegranskat)
|
|
| 32. |
- Teng, Dan, et al.
(författare)
-
Mechanistic Studies on the Stereoselectivity of FFAR1 Modulators
- 2022
-
Ingår i: Journal of Chemical Information and Modeling. - : American Chemical Society (ACS). - 1549-9596 .- 1549-960X. ; 62:15, s. 3664-3675
-
Tidskriftsartikel (refereegranskat)abstract
- Free fatty acid receptor 1 (FFAR1) is a potential therapeutic target for the treatment of type 2 diabetes (T2D). It has been validated that agonists targeting FFAR1 can achieve the initial therapeutic endpoints of T2D, and the epimer agonists (R,S) AM-8596 can activate FFAR1 differently, with one acting as a partial agonist and the other as a full agonist. Up to now, the origin of the stereoselectivity of FFAR1 agonists remains elusive. In this work, we used molecular simulation methods to elucidate the mechanism of the stereoselectivity of the FFAR1 agonists (R)-AM-8596 and (S)-AM-8596. We found that the full agonist (R)-AM-8596 disrupts the residue interaction network around the receptor binding pocket and promotes the opening of the binding site for the G-protein, thereby resulting in the full activation of FFAR1. In contrast, the partial agonist (S)-AM-8596 forms stable electrostatic interactions with FFAR1, which stabilizes the residue network and hinders the conformational transition of the receptor. Our work thus clarifies the selectivity and underlying molecular activation mechanism of FFAR1 agonists.
|
|
| 33. |
- Thinh, N. Q., et al.
(författare)
-
Identification of Ga-interstitial defects in GaNyP1−y and AlxGa1−xNyP1−y
- 2004
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - : APS. - 1098-0121 .- 1550-235X. ; 70:12, s. 121201-
-
Tidskriftsartikel (refereegranskat)abstract
- Two Ga -interstitial (Gai) defects are identified by optically detected magnetic resonance as common grown-in defects in molecular beam epitaxial GaNyP1−y and AlxGa1−xNyP1−y. Characteristic hyperfine structure arising from spin interaction between an unpaired electron and a Ga nucleus is clearly resolved. The observed strong and nearly isotropic hyperfine interaction reveals an electron wave function of A1 symmetry that is highly localized at the Gai and thus a deep-level defect. Our analysis based on first-principles calculations suggests that these defects are complexes containing one Gai2+ .
|
|
| 34. |
|
|
| 35. |
- 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.
|
|
| 36. |
- Tian, Q., et al.
(författare)
-
Super-Large-Scale Hierarchically Porous Films Based on Self-Assembled Eye-Like Air Pores for High-Performance Daytime Radiative Cooling
- 2022
-
Ingår i: Small. - : Wiley. - 1613-6810 .- 1613-6829. ; 18:51, s. 2205091-
-
Tidskriftsartikel (refereegranskat)abstract
- Metal-free polymer daytime radiative cooling coatings with hierarchical eye-like air pores are proposed and fabricated with a super-large-scale film-stretching method. The hierarchically porous film (HPF) can be further coated with polymethyl methacrylate (PMMA) micro-hemispheres, forming coated HPF (cHPF), which do not dramatically change the optical or thermal properties. The cHPF is slightly better with a lower solar absorptivity (2.4%) and a higher thermal emissivity over the atmospheric transparency window (90.1%). The low solar absorptivity is due to the strong scattering of the hierarchical eye-like air pores, while the molecular vibrations and the focusing effect of the PMMA micro-hemispheres contribute to the high emissivity. An average mid-day temperature reduction of 7.92 °C is achieved relative to the air temperature, and the average cooling power reaches 116.0 W m−2, which are much better than the cooling performances of the commercial cooling cushion. During the day, the cHPF-covered simulated building is up to 6.47 and 4.84 °C cooler than the ambient and the white painted counterpart, respectively. The film is durable and resistant to chemical etching, and very promising to use globally, especially in warm and tropical regions.
|
|
| 37. |
- Tu, R., et al.
(författare)
-
Energy saving and consumption reduction in the transportation of petroleum products : A pipeline pricing optimization perspective
- 2023
-
Ingår i: Applied Energy. - : Elsevier Ltd. - 0306-2619 .- 1872-9118. ; 342
-
Tidskriftsartikel (refereegranskat)abstract
- Pipeline transportation is a low-energy and economical mode of transporting petroleum products in the downstream supply chain, however, there is almost no theoretical research on its pricing strategies. The unreasonable pricing strategy has resulted in low utilization of multi-product pipeline capacity as well as high energy consumption of petroleum products transportation. Therefore, this paper aims to improve pipeline turnover and promote the low-carbon transportation market from the perspective of pipeline pricing optimization. We propose an integrated framework for multi-product pipelines that couples pricing strategy and logistics optimization model. This framework simulates the pricing behavior of the pipeline carrier and the corresponding logistics planning behavior of the oil shipper. We apply the framwork to 10 pipeline pricing schemes for two regions in China with different logistics structures, and analyze the economic and environmental benefits of the new strategy. The results show that the well-performing scheme can increase pipeline carriers' revenue by 11.41 million CNY per month, significantly improve the competitive advantage of long-distance pipelines, and reduce energy consumption by 272 tce. Based on these findings, we provide recommendations for policymakers at four levels. In conclusion, the new pricing strategy will help reverse the disadvantageous situation of the pipeline in the competitive market and promote energy conservation in the petroleum products logistics industry.
|
|
| 38. |
- Akerman, Ildem, et al.
(författare)
-
Human Pancreatic β Cell lncRNAs Control Cell-Specific Regulatory Networks
- 2017
-
Ingår i: Cell Metabolism. - : Elsevier BV. - 1550-4131. ; 25:2, s. 400-411
-
Tidskriftsartikel (refereegranskat)abstract
- Recent studies have uncovered thousands of long non-coding RNAs (lncRNAs) in human pancreatic β cells. β cell lncRNAs are often cell type specific and exhibit dynamic regulation during differentiation or upon changing glucose concentrations. Although these features hint at a role of lncRNAs in β cell gene regulation and diabetes, the function of β cell lncRNAs remains largely unknown. In this study, we investigated the function of β cell-specific lncRNAs and transcription factors using transcript knockdowns and co-expression network analysis. This revealed lncRNAs that function in concert with transcription factors to regulate β cell-specific transcriptional networks. We further demonstrate that the lncRNA PLUTO affects local 3D chromatin structure and transcription of PDX1, encoding a key β cell transcription factor, and that both PLUTO and PDX1 are downregulated in islets from donors with type 2 diabetes or impaired glucose tolerance. These results implicate lncRNAs in the regulation of β cell-specific transcription factor networks.
|
|
| 39. |
- Buyanova, Irina, 1960-, et al.
(författare)
-
Analysis of band anticrossing in GaNxP1-x alloys
- 2004
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 70, s. 085209-
-
Tidskriftsartikel (refereegranskat)abstract
- Temperature-dependent absorption, photoluminescence excitation, and spectroscopic ellipsometry measurements are employed to accurately determine compositional and temperature dependences of the conduction band (CB) states in GaNP alloys. The CB edge and the higher lying Γc CB minimum (CBM) are shown to exhibit an apparently anticrossing behavior, i.e., the N-induced redshift of the bandgap energy is accompanied by a matching blueshift of the Γc CBM. The obtained data can be phenomenologically described by the band anticrossing model. By considering strong temperature dependence of the energy of the interacting N level, which has largely been overlooked in earlier studies of GaNP, the interacting N level can be attributed to the isolated substitutional NP and the coupling parameter is accurately determined.
|
|
| 40. |
- Buyanova, Irina, 1960-, et al.
(författare)
-
Band alignment in novel GaInNP/GaAs heterostructures.
- 2007
-
Ingår i: 31th Workshop on Compound Semiconductor Devices and Integrated Circuits WOCSDICE 2007,2007. ; , s. 183-186
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
|
|
| 41. |
|
|
| 42. |
|
|
| 43. |
- Buyanova, Irina, 1960-, et al.
(författare)
-
Direct experimental evidence for unusual effects of hydrogen on the electronic and vibrational properties of GaNxP1−x alloys : a proof for a general property of dilute nitrides
- 2004
-
Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 70:24, s. 245215-245219
-
Tidskriftsartikel (refereegranskat)abstract
- Direct experimental evidence for dramatic effects of hydrogen incorporation on the electronic structure and lattice properties of GaNxP1−x alloys is presented. By employing photoluminescence excitation spectroscopy, postgrowth hydrogenation is shown to reopen the band gap of the GaNP alloys and to efficiently reduce the N-induced coupling between the conduction band states. By Raman spectroscopy, these effects are shown to be accompanied by hydrogen-induced breaking of the Ga-P bond in the alloy, evident from disappearance of the corresponding vibrational mode. According to the performed Raman and x-ray diffraction measurements, the hydrogenation is also found to cause a strong expansion of the GaNP lattice, which changes the sign of strain from tensile in the as-grown GaNP epilayers to compressive in the posthydrogenated structures, due to the formation of complexes between N and H.
|
|
| 44. |
|
|
| 45. |
|
|
| 46. |
- Buyanova, Irina, 1960-, et al.
(författare)
-
Hydrogen passivation of nitrogen in GaNAs and GaNP alloys : How many H atoms are required for each N atom?
- 2007
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 90:2, s. 021920-
-
Tidskriftsartikel (refereegranskat)abstract
- Secondary ion mass spectrometry and photoluminescence are employed to evaluate the origin and efficiency of hydrogen passivation of nitrogen in GaNAs and GaNP. The hydrogen profiles are found to closely follow the N distributions, providing unambiguous evidence for their preferential binding as the dominant mechanism for neutralization of N-induced modifications in the electronic structure of the materials. Though the exact number of H atoms involved in passivation may depend on the conditions of the H treatment and the host matrixes, it is generally found that more than three H atoms are required to bind to a N atom to achieve full passivation for both alloys. © 2007 American Institute of Physics.
|
|
| 47. |
- Buyanova, Irina, 1960-, et al.
(författare)
-
Intrinsic modulation doping in InP-based structures : properties relevant to device applications
- 1999
-
Ingår i: Journal of Crystal Growth. - 0022-0248 .- 1873-5002. ; 201-202, s. 786-789
-
Tidskriftsartikel (refereegranskat)abstract
- In this work we study device-relevant issues, such as doping efficiency and thermal stability, of recently proposed intrinsic modulation doping approach where intrinsic defects (PIn antisites) are used as a carrier source instead of impurity dopants. The InP/InGaAs heterostructure designed to resemble high electron mobility transistor (HEMT) structures, where all the layers were grown at a normal growth temperature 480°C except for the top InP layer which was grown at 265°C, was used as a prototype device. A comparison between the intrinsically doped structure with extrinsically doped HEMTs, which have an identical design except that the top InP layer was instead Si-doped and was grown at 480°C, reveals a high efficiency of the intrinsic doping. The thermal stability of the intrinsically doped HEMT is examined by annealing at temperatures 400-500°C relevant to possible processing steps needed in device fabrication. The observed severe reduction of the carrier concentration after annealing performed without phosphorous gas protection is attributed to the known instability of an InP surface at T>400°C. Thermal stability of the intrinsically doped HEMT is shown to be improved by using an InP cap layer grown at 480°C.
|
|
| 48. |
- Buyanova, Irina, 1960-, et al.
(författare)
-
Modeling of band gap properties of GaInNP alloys lattice matched to GaAs
- 2006
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 88:3, s. 31907-
-
Tidskriftsartikel (refereegranskat)abstract
- Compositional and temperature dependences of the band gap energies of GaInNP alloys, which are lattice matched to GaAs, are determined and modeled by a band anticrossing (BAC) interaction between the localized state of the isolated NP and extended host states. The BAC parameters are deduced as EN =2.1±0.1 eV and CMN =1.7±0.2 eV. The low value of the coupling parameter CMN implies weaker coupling of the N level with the host matrix, presumably due to short range ordering effects, similar to the case of GaInNAs alloys with a high In content. The obtained information is important for future modeling of the electronic structure of the alloys. © 2006 American Institute of Physics.
|
|
| 49. |
- Buyanova, Irina, 1960-, et al.
(författare)
-
Role of nitrogen in photoluminescence up-conversion in GaInNP/GaAs heterostructures
- 2007
-
Ingår i: AIP Conference Proceedings / Volume 893. - : American Institute of Physics (AIP). ; , s. 381-382
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Alloying of disordered GaInP with nitrogen is shown to lead to very efficient PLU in GaInNP/GaAs heterostructures grown by gas source molecular beam epitaxy (GS‐MBE). This is attributed to the N‐induced changes in the band alignment at the GaInNP/GaAs heterointerface from the type I for the N‐free structure to the type II in the samples with N compositions exceeding 0.5%. Based on the performed excitation power dependent measurements, a possible mechanism for the energy upconversion is suggested as being due to the two‐step two‐photon absorption. The photon recycling effect is shown to be important for the structures with N=1%, from time‐resolved PL measurements. © 2007 American Institute of Physics
|
|
| 50. |
- Buyanova, Irina, et al.
(författare)
-
Spin dynamics in ZnO-based materials
- 2010
-
Ingår i: Journal of Superconductivity and Novel Magnetism. - New York, USA : Springer-Verlag New York. - 1557-1939 .- 1557-1947. ; 23:1, s. 161-165
-
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.
|
|
