| 1. |
- Gaffney, K J, et al.
(författare)
-
Observation of structural anisotropy and the onset of liquidlike motion during the nonthermal melting of InSb
- 2005
-
Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 95:12
-
Tidskriftsartikel (refereegranskat)abstract
- The melting dynamics of laser excited InSb have been studied with femtosecond x-ray diffraction. These measurements observe the delayed onset of diffusive atomic motion, signaling the appearance of liquidlike dynamics. They also demonstrate that the root-mean-squared displacement in the [111] direction increases faster than in the [110] direction after the first 500 fs. This structural anisotropy indicates that the initially generated fluid differs significantly from the equilibrium liquid.
|
|
| 2. |
- Grespi, A., et al.
(författare)
-
Probing the electrode-liquid interface using operando total-reflection X-ray absorption spectroscopy
- 2024
-
Ingår i: Surface Science. - : Elsevier B.V.. - 0039-6028 .- 1879-2758. ; 748
-
Tidskriftsartikel (refereegranskat)abstract
- Traditional methods to study electrochemical (EC) processes, although successful, are based on current/voltage measurements, providing information about performances rather than offering a direct observation of chemical and structural changes occurring at the electrode surface. These processes are localized at the electrode-electrolyte interface, the structure of which is the main determinant of their behavior, but most surface sensitive experimental techniques are limited to ex situ conditions, owing to the need for an ultra-high vacuum environment. In this contribution, we report operando X-ray absorption spectroscopy in total external reflection geometry (Refle-XAFS) at P64 beamline (DESY, Hamburg), using a simple and versatile EC flow cell designed for multimodal surface sensitive studies with hard X-ray scattering and spectroscopy techniques. We show that the Refle-XAFS method can be used to study chemical surface changes of industrial alloys and model electrodes in harsh electrochemical environments, without being limited to thin film samples. The surface passive film development and breakdown of a corrosion-resistant Ni-Cr-Mo alloy and the electro-oxidation of polycrystalline gold (poly-Au), relevant for fundamental studies on water electrolysis, were investigated. Despite the strong attenuation of the beam by the electrolyte and the PEEK walls of the EC cell, nanoscale surface oxide films were detected using beam energies down to 8 keV. The passivity breakdown region of Ni alloy 59 in 1 M NaCl at pH 7 and pH 12 was identified, showing differences in the composition of the surface oxides during anodic polarization. The electro-oxidation of poly-Au in 0.05 M H2SO4 was observed, showing a progression from two-dimensional Au1+/3+ to three-dimensional thick Au3+ surface oxide/hydroxide during OER.
|
|
| 3. |
- Micheletti, Chiara, et al.
(författare)
-
Multimodal and Multiscale Characterization of the Bone-Bacteria Interface in a Case of Medication-Related Osteonecrosis of the Jaw
- 2022
-
Ingår i: JBMR Plus. - : Wiley. - 2473-4039. ; 6:12
-
Tidskriftsartikel (refereegranskat)abstract
- Medication-related osteonecrosis of the jaw (MRONJ) is a known side effect of bisphosphonates (BPs). Although bacterial infection is usually present, the etiology of MRONJ remains unknown. Here we apply a multimodal and multiscale (micro-to-nano) characterization approach to investigate the interface between necrotic bone and bacteria in MRONJ. A non-necrotic bone sample was used as control. Both necrotic and non-necrotic bone samples were collected from the jaw of a female individual affected by MRONJ after using BPs for 23 years. For the first time, resin cast etching was used to expose bacteria at the necrotic site. The bone-bacteria interface was also resolved at the nanoscale by scanning transmission electron microscopy (STEM). Nanosized particulates, likely corresponding to degraded bone mineral, were often noted in close proximity to or enclosed by the bacteria. STEM also revealed that the bone-bacteria interface is composed of a hypermineralized front fading into a highly disordered region, with decreasing content of calcium and phosphorus, as assessed by electron energy loss spectroscopy (EELS). This, combined with the variation in calcium, phosphorus, and carbon across the necrotic bone-bacteria interface evaluated by scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) and the lower mineral-to-matrix ratio measured by micro-Raman spectroscopy in necrotic bone, indicates the absence of a mineralization front in MRONJ. It appears that the bone-bacteria interface originates not only from uncontrolled mineralization but also from the direct action of bacteria degrading the bone matrix. (c) 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
|
|
| 4. |
- Sondhauss, Peter, et al.
(författare)
-
Picosecond X-ray studies of coherent folded phonons in a multiple quantum well
- 2005
-
Ingår i: Physical Review Letters. - Lund Univ, Dept Phys, SE-22100 Lund, Sweden. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Malmo Univ, Sch Technol & Soc, S-20506 Malmo, Sweden. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. : AMERICAN PHYSICAL SOC. - 1079-7114 .- 0031-9007. ; 94
-
Tidskriftsartikel (refereegranskat)abstract
- Coherent folded acoustic phonons in a multilayered GaSb/InAs epitaxial heterostructure were generated by femtosecond laser pulses and studied by means of ultrafast x-ray diffraction. Coherent phonons excited simultaneously in the fundamental acoustic branch and the first back-folded branch were detected. This represents the first clear evidence for phonon branch folding based directly on the atomic motion to which x-ray diffraction is sensitive. From a comparison of the measured phonon-modulated x-ray reflectivity with simulations, evidence was found for a reduction of the laser penetration depth. This reduction can be explained by the self-modulation of the refractive index due to photogenerated free carriers.
|
|
| 5. |
- Agardh, Anette, et al.
(författare)
-
Health Risks in Same-Sex Attracted Ugandan University Students : Evidence from Two Cross-Sectional Studies
- 2016
-
Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 11:3
-
Tidskriftsartikel (refereegranskat)abstract
- Widespread discrimination across much of sub-Saharan Africa against persons with same-sex sexuality, including recent attempts in Uganda to extend criminal sanctions against same-sex behavior, are likely to have profound effects on this group's health, health care access, and well-being. Yet knowledge of the prevalence of same-sex sexuality in this region is scarce. This study aimed to systematically examine prevalence of same-sex sexuality and related health risks in young Ugandan adults. We conducted two cross-sectional survey studies in south-western Uganda targeting student samples (n = 980, n = 1954) representing 80% and 72% of the entire undergraduate classes attending a university in 2005 and 2010, respectively. A questionnaire assessed items concerning same-sex sexuality (same-sex attraction/fantasies, same-sex sexual relations), mental health, substance use, experience of violence, risky sexual behavior, and sexual health counseling needs. Our findings showed that same-sex sexual attraction/fantasies and behavior were common among male and female students, with 10-25% reporting having sexual attraction/fantasies regarding persons of the same-sex, and 6-16% reporting same-sex sexual relations. Experiences of same-sex sexuality were associated with health risks, e.g. poor mental health (2010, AOR = 1.5; 95% CI: 1.0-2.3), sexual coercion (2010, AOR 2.9; CI: 1.9-4.6), and unmet sexual health counseling needs (2010, AOR 2.2; CI: 1.4-3.3). This first study of young adults in Uganda with same-sex sexuality found high levels of health needs but poor access to health care. Effective response is likely to require major shifts in current policy, efforts to reduce stigmatization, and reorientation of health services to better meet the needs of this vulnerable group of young people.
|
|
| 6. |
- Ahl, Magnus, et al.
(författare)
-
Translation and validation of the English-language instrument Orthognathic Quality of Life Questionair into Swedish
- 2021
-
Ingår i: Acta Odontologica Scandinavica. - : Informa UK Limited. - 0001-6357 .- 1502-3850. ; 79:1, s. 19-24
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: In orthognathic surgery, understanding the patient’s motives for treatment is a key factor for postoperative patient satisfaction and treatment success. In countries/systems where orthognathic surgery is funded by public means, patients are referred mainly due to functional problems, although studies of quality of life related changes after treatment indicate that psychosocial and aesthetic reasons might be equal or more important for the patient. There is no available validated condition specific instruments in the Swedish language for quality of life evaluation of patients with dentofacial deformities. Aims/objectives: Cross cultural translation and adaptation of the English-language instrument ‘Orthognathic Quality of Life Questionnaire’ (OQLQ) into Swedish. Methods: OQLQ was translated into Swedish. A total of 121 patients in four groups were recruited and the Swedish version of the OQLQ (OQLQ-S) was tested by psychometric methods. Reliability was assessed by internal consistency and test–retest reliability. Validity was evaluated by face, convergent and discriminant validity. Results/findings and conclusions: OQLQ-S is reliable and showed good construct validity and internal consistency and can be used in a Swedish speaking population as a complement to clinical variables to evaluate patients with dentofacial deformity. © 2020, © 2020 Acta Odontologica Scandinavica Society.
|
|
| 7. |
- Burmakin, Mikhail, et al.
(författare)
-
Therapeutic α-1-microglobulin ameliorates kidney ischemia-reperfusion injury.
- 2024
-
Ingår i: American Journal of Physiology - Renal Physiology. - : American Physiological Society. - 1931-857X .- 1522-1466. ; 327:1, s. F103-F112
-
Tidskriftsartikel (refereegranskat)abstract
- α-1-Microglobulin (A1M) is a circulating glycoprotein with antioxidant, heme-binding, and mitochondrial protection properties. The investigational drug RMC-035, a modified therapeutic A1M protein, was assessed for biodistribution and pharmacological activity in a broad set of in vitro and in vivo experiments, supporting its clinical development. Efficacy and treatment posology were assessed in various models of kidney ischemia and reperfusion injury (IRI). Real-time glomerular filtration rate (GFR), functional renal biomarkers, tubular injury biomarkers (NGAL and KIM-1), and histopathology were evaluated. Fluorescently labeled RMC-035 was used to assess biodistribution. RMC-035 demonstrated consistent and reproducible kidney protection in rat IRI models as well as in a model of IRI imposed on renal impairment and in a mouse IRI model, where it reduced mortality. Its pharmacological activity was most pronounced with combined dosing pre- and post-ischemia and weaker with either pre- or post-ischemia dosing alone. RMC-035 rapidly distributed to the kidneys via glomerular filtration and selective luminal uptake by proximal tubular cells. IRI-induced expression of kidney heme oxygenase-1 was inhibited by RMC-035, consistent with its antioxidative properties. RMC-035 also dampened IRI-associated inflammation and improved mitochondrial function, as shown by tubular autofluorescence. Taken together, the efficacy of RMC-035 is congruent with its targeted mechanism(s) and biodistribution profile, supporting its further clinical evaluation as a novel kidney-protective therapy.NEW & NOTEWORTHY A therapeutic A1M protein variant (RMC-035) is currently in phase 2 clinical development for renal protection in patients undergoing open-chest cardiac surgery. It targets several key pathways underlying kidney injury in this patient group, including oxidative stress, heme toxicity, and mitochondrial dysfunction. RMC-035 is rapidly eliminated from plasma, distributing to kidney proximal tubules, and demonstrates dose-dependent efficacy in numerous models of ischemia-reperfusion injury, particularly when administered before ischemia. These results support its continued clinical evaluation.
|
|
| 8. |
- Hartman, Henrik, et al.
(författare)
-
First storage of ion beams in the Double Electrostatic Ion-Ring Experiment : DESIREE
- 2013
-
Ingår i: Review of Scientific Instruments. - : American Institute of Physics (AIP). - 0034-6748 .- 1089-7623. ; 84:5
-
Tidskriftsartikel (refereegranskat)abstract
- We report on the first storage of ion beams in the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. We have produced beams of atomic carbon anions and small carbon anion molecules (Cn-, n = 1, 2, 3, 4) in a sputter ion source. The ion beams were accelerated to 10 keV kinetic energy and stored in an electrostatic ion storage ring enclosed in a vacuum chamber at 13 K. For 10 keV C2- molecular anions we measure the residual-gas limited beam storage lifetime to be 448 s +/- 18 s with two independent detector systems. Using the measured storage lifetimes we estimate that the residual gas pressure is in the 10-14 mbar range. When high current ion beams are injected, the number of stored particles does not follow a single exponential decay law as would be expected for stored particles lost solely due to electron detachment in collision with the residual-gas. Instead, we observe a faster initial decay rate, which we ascribe to the effect of the space charge of the ion beam on the storage capacity.
|
|
| 9. |
- Johansson, C.B., et al.
(författare)
-
3.16 Histological Analysis
- 2017. - 2
-
Ingår i: Comprehensive Biomaterials II. - : Elsevier. - 9780081006924 ; , s. 335-363
-
Bokkapitel (refereegranskat)abstract
- All devices are recognized as foreign body materials once inserted in the living body, and they will all cause foreign body reactions. To determine the degree of integration, both qualitative and quantitative data are obtained by examining histological sections. This technique is the state of the art and has been so for decades. Quantitative analysis is important, but one cannot solely rely on data that computer programs rather rapidly generate. The qualitative examinations are of utmost importance. Tissue which has been properly fixed, processed, and maintained in the laboratories can be used for a broad range of histological analysis. This chapter presents some qualitative and quantitative state-of-the-art techniques used in relation to bone tissue analyses around biomaterials. Methods are described from fixation of tissue, preparation of sections, routine and new techniques adjusted to state-of-the-art techniques, and some complementary techniques. The importance of investigating the tissue reactions in various levels, from light microscopic to molecular, such as the localization of proteins as well as some quantification methods will be presented. In the future, we foresee even more complementary techniques to obtain more information regarding this tissue.
|
|
| 10. |
- John, M. T., et al.
(författare)
-
Recommendations for use and scoring of oral health impact profile versions
- 2022
-
Ingår i: Journal of Evidence-Based Dental Practice. - Philadelphia, PA, United States : Elsevier. - 1532-3382 .- 1532-3390. ; 22:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: OHIP's original seven-domain structure does not fit empirical data, but a psychometrically sound and clinically more plausible structure with the four OHRQoL dimensions Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact has emerged. Consequently, use and scoring of available OHIP versions need to be revisited. Aim: We assessed how well the overall construct OHRQoL and its four dimensions were measured with several OHIP versions (20, 19, 14, and 5 items) to derive recommendations which instruments should be used and how to score them. Methods: Data came from the “Dimensions of OHRQoL Project” and used the project's learning sample (5,173 prosthodontic patients and general population subjects with 49-item OHIP data). We computed correlations among OHIP versions’ summary scores. Correlations between OHRQoL dimensions, on one hand, and OHIP versions’ domain scores or OHIP-5′s items, on the other hand, were also computed. OHIP use and scoring recommendations were derived for psychometrically solid but also practical OHRQoL assessment. Results: Summary scores of 5-, 14-, 19- and 49-item versions correlated highly (r = 0.91–0.98), suggesting similar OHRQoL construct measurement across versions. The OHRQoL dimensions Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact were best measured by the OHIP domain scores for Physical Disability, Physical Pain, Psychological Discomfort, and Handicap, respectively. Conclusion: Recommendations were derived which OHIP should be preferably used and how OHIP versions should be scored to capture the overall construct and the dimensions of OHRQoL. Psychometrically solid and practical OHRQoL assessment in all settings across all oral health conditions can be achieved with the 5-item OHIP.
|
|
