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1.
Cell Mol Life Sci ; 80(4): 89, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36920550

ABSTRACT

Vertebrate lonesome kinase (VLK) is the only known secreted tyrosine kinase and responsible for the phosphorylation of a broad range of secretory pathway-resident and extracellular matrix proteins. However, its cell-type specific functions in vivo are still largely unknown. Therefore, we generated mice lacking the VLK gene (protein kinase domain containing, cytoplasmic (Pkdcc)) in mesenchymal cells. Most of the homozygous mice died shortly after birth, most likely as a consequence of their lung abnormalities and consequent respiratory failure. E18.5 embryonic lungs showed a reduction of alveolar type II cells, smaller bronchi, and an increased lung tissue density. Global mass spectrometry-based quantitative proteomics identified 97 proteins with significantly and at least 1.5-fold differential abundance between genotypes. Twenty-five of these had been assigned to the extracellular region and 15 to the mouse matrisome. Specifically, fibromodulin and matrilin-4, which are involved in extracellular matrix organization, were significantly more abundant in lungs from Pkdcc knockout embryos. These results support a role for mesenchyme-derived VLK in lung development through regulation of matrix dynamics and the resulting modulation of alveolar epithelial cell differentiation.


Subject(s)
Extracellular Matrix , Protein Kinases , Animals , Mice , Protein Kinases/genetics , Organogenesis/genetics , Lung , Mesoderm , Vertebrates , Protein-Tyrosine Kinases
2.
Article in English | MEDLINE | ID: mdl-37848572

ABSTRACT

PURPOSE: Cross-cultural psychosis research has typically focused on a limited number of outcomes (generally symptom-related). It is unknown if the purported superior outcomes for psychosis in some low- and middle-income countries extend to fundamental treatment processes like trust. Addressing this gap, we studied two similar first-episode psychosis programs in Montreal, Canada, and Chennai, India. We hypothesized higher trust in healthcare institutions and providers among patients and families in Chennai at baseline and over follow-up. METHODS: Upon treatment entry and at months 3, 12 and 24, trust in healthcare providers was measured using the Wake Forest Trust scale and trust in the healthcare and mental healthcare systems using two single items. Nonparametric tests were performed to compare trust levels across sites and mixed-effects linear regression models to investigate predictors of trust in healthcare providers. RESULTS: The study included 333 patients (Montreal = 165, Chennai = 168) and 324 family members (Montreal = 128, Chennai = 168). Across all timepoints, Chennai patients and families had higher trust in healthcare providers and the healthcare and mental healthcare systems. The effect of site on trust in healthcare providers was significant after controlling for sociodemographic characteristics known to impact trust. Patients' trust in doctors increased over follow-up. CONCLUSION: This study uniquely focuses on trust as an outcome in psychosis, via a comparative longitudinal analysis of different trust dimensions and predictors, across two geographical settings. The consistent differences in trust levels between sites may be attributable to local cultural values and institutional structures and processes and underpin cross-cultural variations in treatment engagement and outcomes.

3.
Opt Express ; 29(17): 27193-27211, 2021 Aug 16.
Article in English | MEDLINE | ID: mdl-34615140

ABSTRACT

The main advantage of wavelength-dispersive spectrometers applied in X-ray study is their high energy resolution. The design and construction of spectrometer, usually dedicated to the specific experimental systems, for example synchrotron based setups, need information about the characteristics of the main elements of the spectrometer such as X-ray optics elements, crystals and detectors. Such information can be obtained using Monte-Carlo simulations. In this paper, the Monte-Carlo simulations of X-ray tracing in parallel-beam wavelength-dispersive spectrometer (PBWDS), equipped with polycapillary optics, are presented and discussed. The study concentrates on the description of the polycapillary model, simulations of the properties of X-ray polycapillary optics and, finally, on the simulations of X-ray track in the spectrometer designed and installed at the ID21 beamline at the European Synchrotron Radiation Facility (ESRF, Grenoble, France). The results of simulations were compared with experimental data obtained for different registered X-ray energies and spectrometer crystals, showing good agreement. The obtained results showed that the X-ray transmission in the tested polycapillary optics is at the level of 15%, while the divergence of the outgoing beam changes from 8 mrad to 3 mrad with an increase of photon energy from 2 keV to 10 keV. The spectrometer provides an energy resolution of 5 eV and 33 eV in the energy range of 1.4 keV - 6.5 keV. The developed simulation program can be successfully used for the construction of spectrometers dedicated to the different experimental conditions.

4.
J Microsc ; 270(2): 156-169, 2018 05.
Article in English | MEDLINE | ID: mdl-29240245

ABSTRACT

Mollusc shells are complex organomineral structures, the arrangement and composition depending on the species. Most studies are dedicated to shells composed of an aragonite nacreous and a calcite prismatic layer, so the nacreous prismatic model based on Pinctada and Atrina-Pinna. Here, we studied the micro- and nanostructure, the mineralogy and composition of a nacroprismatic bivalve species: Unio pictorum. The prismatic layer of Unio is aragonite, and the inner structure of the prismatic units strongly differs from those of the calcitic layers. The shape of the prisms varies depending on their growth stage. The first layers of nacre are similar to those of gastropods (columnar nacre), then evolve towards the typical bivalve arrangement (sheet nacre). Na, Sr, Mg, P and S are present in both prisms and nacre. The organic prismatic envelopes are rich in sulphur amino acids, whereas organic sulphate is present within the prisms and the nacreous tablets. P is present as phosphate, probably a mixture of organic and mineral complex. Chemical distribution maps confirm the absence of an organic membrane between the nacre and the prisms. The comparison of the structure, mineralogy and composition of Unio pictorum and different species show the diversity of nacroprismatic shells, and that these features are taxonomically dependent.


Subject(s)
Animal Shells/anatomy & histology , Animal Shells/chemistry , Minerals/analysis , Organic Chemicals/analysis , Unio/anatomy & histology , Unio/chemistry , Animals
6.
Child Obes ; 2023 Jul 13.
Article in English | MEDLINE | ID: mdl-37440174

ABSTRACT

Background: Childhood obesity (CO) is rapidly increasing in prevalence and developing into a health crisis of developed nations. The condition is associated with increased risk of developing various comorbidities later in life. Current treatment algorithms primarily target family education. Thus, this study aims to understand the quality of information online regarding CO and common comorbidities, determine the readability of online information, and report patterns in public interest over time using Google Trends. Methods: Four validated quality of information tools and 6 readability tools were implemented across 36 websites derived from 4 Google searches. Pearson's correlation coefficient was used to determine the associations between Google Trends' relative search volumes (RSVs) and biennial BMI-based cumulative proportion of CO. Results: Results showed variable information quality among the websites as scores ranged from "fair" to "very poor." Using six readability formulas, no website scored at or below the sixth grade reading level recommended by the American Medical Association. Google Trends' RSVs for the term "Childhood Obesity" were repeatedly increased in the months that fall in the US academic school year (October-November and February-May), and decreased within months in the US vacation periods (December-January and June-September). Search volumes were also negatively correlated with CO and pediatric type 2 diabetes prevalence. Conclusions: In summary, while Google Trends analysis showed that schools may play a role in increasing interest and awareness online, quality of information and readability analysis displayed that the information and its accessibility are far too variable to be reliable.

7.
Res Sq ; 2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36824772

ABSTRACT

Purpose: Cross-cultural psychosis research has typically focused on a limited number of outcomes (generally symptom-related). It is unknown if the purported superior outcomes for psychosis in some low- and middle-income countries extend to fundamental treatment processes like trust. Addressing this gap, we studied two similar first-episode psychosis programs in Montreal, Canada and Chennai, India. We hypothesized higher trust in healthcare institutions and providers among patients and families in Chennai at baseline and over follow-up. Methods: Upon treatment entry and at months 3, 12 and 24, trust in healthcare providers was measured using the Wake Forest Trust scale and trust in the healthcare and mental healthcare systems using two single items. Non-parametric tests were performed to compare trust levels across sites and mixed-effects linear regression models to investigate predictors of trust in healthcare providers. Results: The study included 333 patients (Montreal=165, Chennai=168) and 324 family members (Montreal=128, Chennai=168). Across all timepoints, Chennai patients and families had higher trust in healthcare providers and the healthcare and mental healthcare systems. The effect of site on trust in healthcare providers was significant after controlling for sociodemographic characteristics known to impact trust. Patients' trust in doctors increased over follow-up. Conclusion: This study uniquely focuses on trust as an outcome in psychosis, via a comparative longitudinal analysis of different trust dimensions and predictors, across two geographical settings. The consistent differences in trust levels between sites may be attributable to local cultural values and institutional structures and processes and underpin cross-cultural variations in treatment engagement and outcomes.

8.
Transcult Psychiatry ; : 13634615231187252, 2023 Jul 30.
Article in English | MEDLINE | ID: mdl-37519012

ABSTRACT

Several migrant populations have been identified worldwide as high-risk groups for psychosis because of their experience of social adversity. Recent evidence suggests that the local contexts in which these populations live should be addressed in their complexity to take into account individual and larger societal environmental aspects. This study aimed to assess the lived experiences of a group of migrant Cape Verdean patients, who had been recently hospitalized for a first episode of psychosis in a mental health service on the outskirts of Lisbon, Portugal. The study used Photovoice, a qualitative participatory research method in which people's experiences are documented through photography. Six individuals were recruited, and five weekly sessions were conducted to collect data that were analyzed thematically. Emergent themes addressed two main categories of well-being and illness. Participant concepts of well-being were rooted in a definition of freedom encompassing cultural expression, conveyed by familiar environments and supporting communities. Cultural differences may be experienced as important obstacles for well-being and can be associated with feelings of oppression and guilt. Participants' accounts focused on positive aspects of life despite illness and on personal concepts of recovery. The study findings contribute to knowledge of the dynamics of migrants' social experience and underscore the importance of socially and culturally informed mental healthcare institutions.

9.
Materials (Basel) ; 16(18)2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37763603

ABSTRACT

To reduce the environmental impacts from sodium silicate synthesis, a ceramic method was suggested, with sugarcane bagasse ash (SCBA) as the source of silicon dioxide and sodium carbonate. Although the production of sodium silicate is carried out on a large scale, it should be noted that its process requires temperatures above 1000 °C; it also requires the use of highly corrosive agents such as sodium hydroxide and chlorine gas to neutralize the remaining sodium hydroxide. In the present study, the synthesis temperatures were reduced to 800 °C with a reaction time of 3 h by pressing equimolar mixtures of previously purified SCBA and sodium carbonate; then, heat treatment was carried out under the indicated conditions. The resulting materials were analyzed with Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Among the crystalline phases, calcium disodium silicate was identified, in addition to sodium silicate; thus, it was inferred that the other components of the ash can interfere with the synthesis of silicate. Therefore, in order to obtain the highest composition of sodium silicate, a leaching treatment of the SCBA is required.

10.
Porto Biomed J ; 8(3): e219, 2023.
Article in English | MEDLINE | ID: mdl-37383526

ABSTRACT

Background: The coronavirus disease 2019 (COVID-19) was classified as a pandemic in March 2020 by the World Health Organization. The Pfizer-BioNTech COVID-19 vaccine was the first to be authorized in the European Union, based on data from phase 1, 2, and 3 clinical trials of limited duration. Concerns have been raised regarding the vaccine's safety profile. Some of the adverse drug reactions (ADRs) associated with vaccines may not have been identified during clinical trials. This study aimed to identify ADRs associated with the Pfizer-BioNTech vaccine in health care professionals at a Portuguese tertiary university hospital. Methods: The data used in this analysis consist of ADRs reported through a spontaneous notification system from vaccines administered between December 27, 2020, and January 31, 2021. ADRs were categorized according to the MedDRA terminology. Results: A total of 8,605 Pfizer-BioNTech vaccines were administered to 4568 health care professionals. ADRs were reported among 520 of the vaccines, with an incidence of 13.56% in women and 5.31% in men. The mean age of the population reporting ADRs was 41.52 years, with a standard deviation of 9.83 years. The most frequent ADRs were myalgia (n = 274), headache (n = 199), pyrexia (n = 164), injection site pain (n = 160), fatigue (n = 84), nausea (n = 81), chills (n = 65), lymphadenopathy (n = 64), and arthralgia (n = 53). Hypersensitivity reactions occurred in 15 health care professionals, with no anaphylactic reactions observed. A total of four Important Medical Events were observed, which consisted of two cases of syncope, one case of sudden hearing loss, and one case of transverse myelitis. Conclusion: The vaccine was well-tolerated among the study participants. Reactogenicity was greater after the second dose. The incidence of ADRs was higher in women and individuals aged between 40 to 49 years. Systemic adverse reactions were most frequently reported. Systematic monitoring of ADRs of COVID-19 vaccines in real-life context is essential for a more robust establishment of its safety profile.

11.
J Struct Biol ; 177(2): 248-58, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22182732

ABSTRACT

Very little is known about the sub-cellular distribution of metal ions in cells. Some metals such as zinc, copper and iron are essential and play an important role in the cell metabolism. Dysfunctions in this delicate housekeeping may be at the origin of major diseases. There is also a prevalent use of metals in a wide range of diagnostic agents and drugs for the diagnosis or treatment of a variety of disorders. This is becoming more and more of a concern in the field of nanomedicine with the increasing development and use of nanoparticles, which are suspected of causing adverse effects on cells and organ tissues. Synchrotron-based X-ray and Fourier-transformed infrared microspectroscopies are developing into well-suited sub-micrometer analytical tools for addressing new problems when studying the role of metals in biology. As a complementary tool to optical and electron microscopes, developments and studies have demonstrated the unique capabilities of multi-keV microscopy: namely, an ultra-low detection limit, large penetration depth, chemical sensitivity and three-dimensional imaging capabilities. More recently, the capabilities have been extended towards sub-100nm lateral resolutions, thus enabling sub-cellular chemical imaging. Possibilities offered by these techniques in the biomedical field are described through examples of applications performed at the ESRF synchrotron-based microspectroscopy platform (ID21 and ID22 beamlines).


Subject(s)
Biomedical Technology , Synchrotrons , Animals , BALB 3T3 Cells , Dopaminergic Neurons/metabolism , France , Hepatocytes/metabolism , Humans , Male , Manganese/metabolism , Melanins/metabolism , Metals/metabolism , Mice , Microspectrophotometry/methods , PC12 Cells , Phosphorus/metabolism , Potassium/metabolism , Rats , Spectroscopy, Fourier Transform Infrared , Spermatozoa/metabolism , X-Rays
12.
Sante Ment Que ; 46(2): 331-364, 2021.
Article in French | MEDLINE | ID: mdl-35617504

ABSTRACT

Objectives To synthesize the available epidemiological and clinical evidence relevant to the mental health care of migrant, ethnic minority and Indigenous populations in the context of early psychosis. Methods This study provides a narrative review of the literature on psychosis in these populations, including issues related to the provision of early intervention services for psychosis. Results Migrant status has long been reported as a significant risk factor for psychosis in many geographic contexts. This increased risk among migrants seems to persist beyond the first generation and has been found to be higher in all migrant populations, but especially for black ethnic minorities and individuals migrating from economically developing countries to developed ones. Recent evidence suggests that this higher risk is at least in part due to migrants' and minorities' cumulative exposure to social adversities, such as racial discrimination, marginalization and socio-economic disadvantage. Systemic racism affects migrant and minority populations by creating bias in diagnostic practices and aggravating treatment disparities in addition to contributing to causation of psychosis. Furthermore, migrant and ethnic minority groups are known to seek mental healthcare after longer delays, to be more frequently forcibly hospitalized, to disengage from treatment prematurely and to be less satisfied with their treatment. The consideration of social and cultural context and factors is essential to the provision of good healthcare, especially in a culturally diverse society. Furthermore, acknowledging power relationships that stem from the societal context and shape institutions and models of care is a key step towards structural competence and safety in mental healthcare. Several strategies have been proposed to make mental healthcare services and systems more culturally and structurally competent. These include the use of interpreters and cultural brokers, tailored assessments and specialised cultural interventions. However, these strategies have yet to be adopted broadly in early intervention for psychosis. Conclusion Given its emphasis on meaningful engagement and person-centered care, early intervention should integrate inclusive, structurally competent and context-informed interventions as a priority. Efforts must be made to apply knowledge from and adapt the tools of social and cultural psychiatry to the field of early intervention in psychosis. Sociocultural considerations, hitherto inconsistently applied in psychosis research and service design in Quebec, are especially relevant to the province given its distinct linguistic context, its increasing cultural diversity, and its ongoing effort to systematize and expand the delivery of early intervention services.


Subject(s)
Mental Health Services , Psychotic Disorders , Transients and Migrants , Ethnicity , Humans , Minority Groups , Psychotic Disorders/therapy
13.
PLoS One ; 16(2): e0246444, 2021.
Article in English | MEDLINE | ID: mdl-33544736

ABSTRACT

BACKGROUND: Only approximately one in five adults are offered HIV testing by providers when seeking care for symptoms of acute illness in Sub-Saharan Africa. Our aims were to estimate testing coverage and identify predictors of provider-initiated testing and counselling (PITC) and barriers to PITC implementation in this population. METHODS: We assessed HIV testing coverage among adult outpatients 18-39 years of age at four public and two private health facilities in coastal Kenya, during a 3- to 6-month surveillance period at each facility. A subset of patients who reported symptoms including fever, diarrhoea, fatigue, body aches, sore throat or genital ulcers were enrolled to complete a questionnaire independently of PITC offer. We assessed predictors of PITC in this population using generalised estimating equations and identified barriers to offering PITC through focus group discussion with healthcare workers (HCW) at each facility. RESULTS: Overall PITC coverage was 13.7% (1600 of 11,637 adults tested), with 1.9% (30) testing positive. Among 1,374 participants enrolled due to symptoms, 378 (27.5%) were offered PITC and 352 (25.6%) were tested, of whom 3.7% (13) tested positive. Among participants offered HIV testing, 93.1% accepted it; among participants not offered testing, 92.8% would have taken an HIV test if offered. The odds of completed PITC were increased among older participants (adjusted odds ratio [aOR] 1.7, 95% confidence interval [CI] 1.4-2.1 for 30-39 years, relative to 18-24 years), men (aOR 1.3, 95% CI 1.1-1.7); casual labourers (aOR 1.3, 95% CI 1.0-1.7); those paying by cash (aOR 1.2, 95% CI 1.0-1.4) or insurance (aOR 3.0, 95% CI 1.5-5.8); participants with fever (aOR 1.5, 95% CI 1.2-1.8) or genital ulcers (aOR 4.0, 95% CI 2.7-6.0); and who had tested for HIV >1 year ago (aOR 1.4, 95% CI 1.0-2.0) or had never tested (aOR 2.2, 95% CI 1.5-3.1). Provider barriers to PITC implementation included lack of HCW knowledge and confidence implementing guidelines, limited capacity and health systems constraints. CONCLUSION: PITC coverage was low, though most patients would accept testing if offered. Missed opportunities to promote testing during care-seeking were common and innovative solutions are needed.


Subject(s)
Counseling/statistics & numerical data , HIV Infections , HIV Testing , Health Facilities/statistics & numerical data , Mass Screening/methods , Patient Acceptance of Health Care , Adolescent , Adult , Female , HIV Infections/diagnosis , HIV Infections/epidemiology , HIV-1/isolation & purification , Health Knowledge, Attitudes, Practice , Health Personnel/education , Humans , Kenya/epidemiology , Male , Patient Acceptance of Health Care/statistics & numerical data , Surveys and Questionnaires , Young Adult
14.
J Synchrotron Radiat ; 17(3): 400-8, 2010 May.
Article in English | MEDLINE | ID: mdl-20400840

ABSTRACT

The development of a wavelength-dispersive spectrometer for microfluorescence analysis at the X-ray Microscopy ID21 beamline of the European Synchrotron Radiation Facility (ESRF) is reported. The spectrometer is based on a polycapillary optic for X-ray fluorescence collection and is operated in a flat-crystal geometry. The design considerations as well as operation characteristics of the spectrometer are presented. The achieved performances, in particular the energy resolution, are compared with the results of Monte Carlo simulations. Further improvement in the energy resolution, down to approximately eV range, by employing a double-crystal geometry is examined. Finally, examples of applications requiring both spatial and spectral resolutions are presented.

15.
J Synchrotron Radiat ; 17(2): 149-57, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20157265

ABSTRACT

X-ray microscopy is capable of imaging particles in the nanometer size range directly with sub-micrometer spatial resolution and can be combined with high spectral resolution for spectromicroscopy studies. Two types of microscopes are common in X-ray microscopy: the transmission X-ray microscope and the scanning transmission X-ray microscope; their set-ups are explained in this paper. While the former takes high-resolution images from an object with exposure times of seconds or faster, the latter is very well suited as an analytical instrument for spectromicroscopy. The morphology of clusters or particles from soil and sediment samples has been visualized using a transmission X-ray microscope. Images are shown from a cryo-tomography experiment based on X-ray microscopy images to obtain information about the three-dimensional structure of clusters of humic substances. The analysis of a stack of images taken with a scanning transmission X-ray microscope to combine morphology and chemistry within a soil sample is shown. X-ray fluorescence is a method ideally applicable to the study of elemental distributions and binding states of elements even on a trace level using X-ray energies above 1 keV.


Subject(s)
Soil/analysis , Spectrometry, X-Ray Emission/methods , Cryoelectron Microscopy/methods , Ecology , Microscopy/instrumentation , Microscopy, Electron, Transmission
16.
Microsc Microanal ; 16(1): 91-8, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20030908

ABSTRACT

The organic interprismatic layers of the mollusc Pinctada margaritifera are studied using a variety of highly spatially-resolved techniques to establish their composition and structure. Our results show that both the interlamellar sheets of the nacre and interprismatic envelopes form layered structures. Additionally, these organic layers are neither homogeneous in composition, nor continuous in their structure. Both structures play a major role in the biomineralization process and act as a boundary between mineral units.


Subject(s)
Minerals/analysis , Organic Chemicals/analysis , Pinctada/chemistry , Pinctada/ultrastructure , Animals , Electron Probe Microanalysis , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Pinctada/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Spectrometry, Mass, Secondary Ion , Spectroscopy, Fourier Transform Infrared , X-Ray Absorption Spectroscopy
17.
TH Open ; 4(2): e127-e137, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32607466

ABSTRACT

Introduction There is scarce real-world experience regarding direct oral anticoagulants (DOACs) perioperative management. No study before has linked bridging therapy or DOAC-free time (pre-plus postoperative time without DOAC) with outcome. The aim of this study was to investigate real-world management and outcomes. Methods RA-ACOD is a prospective, observational, multicenter registry of adult patients on DOAC treatment requiring surgery. Primary outcomes were thrombotic and hemorrhagic complications. Follow-up was immediate postoperative (24-48 hours) and 30 days. Statistics were performed using a univariate and multivariate analysis. Data are presented as odds ratios (ORs [95% confidence interval]). Results From 26 Spanish hospitals, 901 patients were analyzed (53.5% major surgeries): 322 on apixaban, 304 on rivaroxaban, 267 on dabigatran, 8 on edoxaban. Fourteen (1.6%) patients suffered a thrombotic event, related to preoperative DOAC withdrawal (OR: 1.57 [1.03-2.4]) and DOAC-free time longer than 6 days (OR: 5.42 [1.18-26]). Minor bleeding events were described in 76 (8.4%) patients, with higher incidence for dabigatran (12.7%) versus other DOACs (6.6%). Major bleeding events occurred in 17 (1.9%) patients. Bridging therapy was used in 315 (35%) patients. It was associated with minor (OR: 2.57 [1.3-5.07]) and major (OR: 4.2 [1.4-12.3]) bleeding events, without decreasing thrombotic events. Conclusion This study offers real-world data on perioperative DOAC management and outcomes in a large prospective sample size to date with a high percentage of major surgery. Short-term preprocedural DOAC interruption depending on the drug, hemorrhagic risk, and renal function, without bridging therapy and a reduced DOAC-free time, seems the safest practice.

18.
J Phys Chem A ; 113(12): 2750-6, 2009 Mar 26.
Article in English | MEDLINE | ID: mdl-19296706

ABSTRACT

Sulfur K-edge XANES has been measured for three sulfur model compounds, dibenzothiophene, dibenzothiophene sulfone, and aliphatic sulfur (DL-methionine). The spectra have been simulated with Density Functional Theory (DFT) by using a number of methods, including the half-core-hole approximation. Dipole transition elements were calculated and the transitions were convoluted with linearly increasing Gaussian functions in the first 20 eV of the near-edge region. In the case of dibenzothiophene, relaxation of the first excited states in the presence of the core-hole gave a further improvement. The theoretical results reproduce well the features of the spectra and give insight in the relation between geometric structure and molecular orbitals. Though DL-methionine and dibenzothiophene show a similar sharp rise of the white line, their molecular levels are quite different, pointing out the difficulties in finding useful "fingerprints" in the spectra for specific compounds.


Subject(s)
Methionine/chemistry , Sulfur Compounds/chemistry , Thiophenes/chemistry , Models, Molecular , Spectrum Analysis , X-Rays
19.
J Phys Condens Matter ; 21(29): 295801, 2009 Jul 22.
Article in English | MEDLINE | ID: mdl-21828536

ABSTRACT

By means of x-ray absorption near-edge structure (XANES) several Ga(1-x)Mn(x)N (0.03

20.
J Neurosci Nurs ; 56(4): 104, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38833433
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