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1.
J Occup Rehabil ; 34(1): 87-99, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37439945

ABSTRACT

PURPOSE: A barrier for reemployment of people with mental health issues/mental illness (MHI) is workplace stigma and discrimination. In this RCT the effectiveness of a stigma-awareness intervention addressing finding work, retaining work and decisional stress were evaluated. METHODS: A cluster RCT was conducted in 8 Dutch municipal practices. Randomisation took place at practice level. Participants were unemployed people with MHI, receiving social benefits. The intervention consisted of a decision aid for workplace disclosure for participants and a 2 × 3 h stigma-awareness training for their employment specialists. Primary outcomes were measured at baseline, 3-, 6- and 12-months. Multilevel analyses, containing random intercepts of participants nested in organizations, were conducted to analyse the effects of the intervention. RESULTS: Participants (N = 153) were randomized to an experimental (n = 76) or control group (n = 77). At six months, significantly more participants of the experimental group (51%) had found work compared to the control group (26%). At twelve months, significantly more participants of the experimental group (49%) had retained work compared to the control group (23%). Intention-to-treat analyses showed that randomization to the experimental group was associated with finding (OR(95%CI) = 7.78(1.33-45.53), p = 0.02) and retaining (OR(95%CI) = 12.15(2.81-52.63), p < 0.01) work more often at twelve months. Analyses showed that the experimental and control group did not differ in decisional stress. CONCLUSIONS: Our stigma awareness intervention was effective for finding and retaining work. As the percentage of people who found and retained work almost doubled, this suggests that on a societal level, a vast number of unemployed people could be reemployed with a relatively simple intervention. TRIAL REGISTRATION: The study was retrospectively registered at the Dutch Trial Register (TRN: NL7798, date: 04-06-2019).


Subject(s)
Mental Disorders , Mental Health , Humans , Social Stigma , Employment , Workplace , Mental Disorders/therapy , Mental Disorders/psychology
2.
J Occup Rehabil ; 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37878158

ABSTRACT

PURPOSE: As stigma is a barrier to work participation of unemployed people with mental health issues/mental illness (MHI), a stigma awareness intervention can be helpful to make informed decisions about disclosing MHI. The aim of this process evaluation was to investigate the feasibility of a stigma awareness intervention, to explore experiences of clients and their employment specialists; and to give recommendations for further implementation. METHODS: The intervention consisted of a stigma awareness training for employment specialists and a decision aid tool for their clients with (a history of) MHI. For the process evaluation, six process components of the Linnan & Stecklar framework were examined: recruitment, reach, dose delivered, dose received, fidelity and context. Using a mixed-methods design, quantitative and qualitative data were collected and analyzed. RESULTS: The six components showed the intervention was largely implemented as planned. Questionnaire data showed that 94% of the clients found the tool useful and 87% would recommend it to others. In addition, more than half (54%) indicated the tool had been helpful in their disclosure decision. Qualitative data showed that participants were mainly positive about the intervention. Nevertheless, only a minority of clients and employment specialists had actually discussed the tool together. According to both, the intervention had increased their awareness of workplace stigma and the disclosure dilemma. CONCLUSION: The implementation of a stigma awareness intervention was feasible and did increase stigma awareness. Experiences with the intervention were mainly positive. When implementing the tool, it is recommended to embed it in the vocational rehabilitation system, so that discussing the disclosure dilemma becomes a routine. TRAIL REGISTER: The study was retrospectively registered at the Dutch Trial Register (TRN: NL7798, date: 04-06-2019).

3.
Biomech Model Mechanobiol ; 22(6): 1815-1828, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37405536

ABSTRACT

Adverse ventricular remodeling following acute myocardial infarction (MI) may induce ventricular dilation, fibrosis, and loss of global contractile function, possibly resulting in heart failure (HF). Understanding the relation between the time-dependent changes in material properties of the myocardium and the contractile function of the heart may further our understanding of the development of HF post-MI and guide the development of novel therapies. A finite element model of cardiac mechanics was used to model MI in a thick-walled truncated ellipsoidal geometry. Infarct core and border zone comprised 9.6 and 8.1% of the LV wall volume, respectively. Acute MI was modeled by inhibiting active stress generation. Chronic MI was modeled by the additional effect of infarct material stiffening, wall thinning and fiber reorientation. In acute MI, stroke work decreased by 25%. In the infarct core, fiber stress was reduced but fiber strain was increased, depending on the degree of infarct stiffening. Fiber work density was equal to zero. Healthy tissue adjacent to the infarct showed decreased work density depending on the degree of infarct stiffness and the orientation of the myofibers with respect to the infarct region. Thinning of the wall partially restored this loss in work density while the effects of fiber reorientation were minimal. We found that the relative loss in pump function in the infarcted heart exceeds the relative loss in healthy myocardial tissue due to impaired mechanical function in healthy tissue adjacent to the infarct. Infarct stiffening, wall thinning and fiber reorientation did not affect pump function but did affect the distribution of work density in tissue adjacent to the infarct.


Subject(s)
Heart Failure , Myocardial Infarction , Humans , Myocardium , Heart Ventricles , Ventricular Remodeling
4.
Chem Sci ; 13(35): 10251-10259, 2022 Sep 14.
Article in English | MEDLINE | ID: mdl-36277633

ABSTRACT

This work establishes structure-property relationships in Ru-based catalytic systems for selective hydrodeoxygenation of ketones to alkenes by combining extensive catalytic testing, in situ X-ray absorption spectroscopy (XAS) under high pressures and temperatures and ex situ XAS structural characterization supported by density functional theory (DFT) calculations. Catalytic tests revealed the difference in hydrogenation selectivity for ketones (exemplified by acetone) or alkenes (exemplified by propene) upon changing the reaction conditions, more specifically in the presence of CO during a pretreatment step. XAS data demonstrated the evolution of the local ruthenium structure with different amounts of Cl/Br and CO ligands. In addition, in the absence of CO, the catalyst was reduced to Ru0, and this was associated with a significant decrease of the selectivity for ketone hydrogenation. For the Ru-bromide carbonyl complex, selectivity towards acetone hydrogenation over propene hydrogenation was explained on the basis of different relative energies of the first intermediate states of each reaction. These results give a complete understanding of the evolution of the Ru species, used for the catalytic valorization of biobased polyols to olefins in ionic liquids, identifying the undesired deactivation routes as well as possibilities for reactivation.

5.
BMC Psychiatry ; 22(1): 662, 2022 10 27.
Article in English | MEDLINE | ID: mdl-36303128

ABSTRACT

BACKGROUND: Internalized stigma can have numerous negative effects on the well-being and employment of people with mental illness. Brief, valid, and reliable measures are needed to get a better understanding of self-stigmatization. The aim of this study is to translate the brief version of the Internalized Stigma of Mental Illness (ISMI-10) scale into a Dutch version and to assess the reliability and validity of this Dutch version in a sample of employees with mental illness. METHODS: The ISMI-10 was translated into Dutch using the forward-backward translation procedure. The sample consisted of 161 employees with mental illness. Internal consistency was evaluated and the retest reliability was tested with 68 respondents. The construct validity was evaluated by testing convergent and divergent validity. RESULTS: The Dutch ISMI-10 showed good internal consistency (α = 0.83) and good test-retest reliability (r = 0.73). The Dutch ISMI-10 demonstrated excellent convergent validity; high correlations were found between the Dutch ISMI-10 and hope (r = -0.54), anxiety and depression (r = 0.59), self-esteem (r = -0.56), and empowerment (r = - 0.59). Acceptable divergent validity was indicated; small correlations were found between the Dutch ISMI-10 and the physical functioning subscale (r = -0.27) and the role limitation due to physical problems subscale (r = -0.21), and medium correlations were found between the Dutch ISMI-10 and the general health subscale (r = -0.36). CONCLUSION: The Dutch ISMI-10 demonstrated adequate psychometric properties for assessing internalized stigma and can be used by researchers in Dutch speaking countries to get a better understanding of self-stigmatization among people with mental illness.


Subject(s)
Mental Disorders , Social Stigma , Humans , Psychometrics , Reproducibility of Results , Stereotyping , Surveys and Questionnaires
6.
J Occup Rehabil ; 32(4): 652-663, 2022 12.
Article in English | MEDLINE | ID: mdl-35137273

ABSTRACT

Purpose The decision whether to disclose mental illness at work can have important positive and negative consequences for sustainable employment and well-being. The aim of the study is (1) to examine workers' expectations of outcomes of mental illness disclosure in the workplace and to evaluate their expectations regarding which factors are of influence on these outcomes, (2) to identify distinct subgroups of workers, and (3) to characterize these subgroups in terms of personal, sociodemographic, and work-related characteristics. Methods In this cross-sectional survey study, a sample of 1224 Dutch workers was used. Latent Class Analysis (LCA) was used to identify classes of workers based on expected workplace mental illness outcomes. A three-step approach LCA was chosen to investigate whether the classes differed in characteristics. Results The majority of workers expected predominantly positive outcomes of workplace mental illness disclosure (e.g., being able to be one's authentic self; 82.4%), even though they simultaneously expected disclosure to lead to advancement-related discrimination (e.g., lower chances of contract renewal; or getting a promotion; 68.4% and 57%, respectively). Six distinct subgroups of workers were identified based on expected workplace mental illness disclosure outcomes: two positive classes (50.1%), two negative classes (33.3%), and two classes who indicated not to know what the outcomes would be (16.7%). Significant differences between the classes were found on personal experience, work-related association with mental illness, gender, educational level, and workplace atmosphere. Conclusion The disclosure process is complex, as most workers were optimistic (i.e., expected generally positive outcomes) whilst simultaneously expecting workplace discrimination. Subgroup differences in expectations regarding workplace mental illness disclosure outcomes were found.


Subject(s)
Disclosure , Mental Disorders , Humans , Cross-Sectional Studies , Motivation , Employment , Workplace
7.
J Occup Rehabil ; 32(3): 365-379, 2022 09.
Article in English | MEDLINE | ID: mdl-34487290

ABSTRACT

PURPOSE: Studies are increasingly showing that health related stigma is a barrier to employment, but it is not known how. The aim of this systematic review is to identify, appraise and analyse studies that have directly or indirectly addressed ways in which stigma affects sustainable employment and well-being at work of people with disabilities. METHODS: Using a multiphase screening process, this review is based on a comprehensive literature search (2000-2019) carried out in six electronic databases: Embase, Web of Science, Medline Ovid, Cochrane CENTRAL, PsycINFO and Google Scholar. RESULTS: 7.263 publications were identified; 96 studies were found eligible to be included in the review. 72% of the studies were conducted in North America or Europe. Few studies directly assessed how stigma affects the employment of people with disabilities. Most studies highlighted that attitudes and behaviour of employers formed a barrier to employment, as well as anticipated stigma and self-stigma in people with health problems. However, the findings also showed that the attitudes and behaviour of co-workers, health care professionals, reintegration professionals, customers, and family and friends could act as a barrier to employment although these influences are under-researched. Although many similarities were seen in the relevant findings of studies about both physical and mental disabilities, several nuances were found. CONCLUSION: Stigma hampers sustainable employment and well-being in multiple ways. Whereas the number of publications on this topic is rapidly increasing, the roles of health care professionals, reintegration professionals, co-workers, customers, and family and friends particularly warrant more attention.


Subject(s)
Disabled Persons , Employment , Attitude , Health Personnel , Humans , Social Stigma
8.
J Phys Chem A ; 125(32): 7080-7091, 2021 Aug 19.
Article in English | MEDLINE | ID: mdl-34351779

ABSTRACT

A novel approach for the analysis of extended X-ray absorption fine structure (EXAFS) spectra is developed exploiting an inverse machine learning-based algorithm. Through this approach, it is possible to explore and account for, in a precise way, the nonlinear geometry dependence of the photoelectron backscattering phases and amplitudes of single and multiple scattering paths. In addition, the determined parameters are directly related to the 3D atomic structure, without the need to use complex parametrization as in the classical fitting approach. The applicability of the approach, its potential and the advantages over the classical fit were demonstrated by fitting the EXAFS data of two molecular systems, namely, the KAu (CN)2 and the [RuCl2(CO)3]2 complexes.

9.
Trials ; 21(1): 443, 2020 May 29.
Article in English | MEDLINE | ID: mdl-32471478

ABSTRACT

BACKGROUND: Unemployment rates are higher among people with mental health issues/illness (MHI) than in the general working population, and many of them face the dilemma of whether or not to disclose their MHI when searching for employment. Disclosure can lead to rejection and discrimination, but alternatively can also have important advantages that may be necessary to retain employment. Whether disclosure decisions lead to sustainable employment depends on many factors, of which unemployed people themselves can only influence their decision to disclose or not and the way in which they communicate. This study evaluates the cost-effectiveness of an intervention to support unemployed people with MHI in their disclosure decision and communication. METHODS: This is a two-armed, clustered, randomized controlled trial with longitudinal design and randomization at organization level. An intervention will be examined, which consists of a disclosure decision aid tool (CORAL.NL) for unemployed people and workplace stigma-awareness training especially designed for employment specialists, which focusses on how to support unemployed people in their disclosure decisions. Participants in the intervention group are unemployed people who receive support from trained employment specialists from organizations allocated to the intervention group, and receive the CORAL.NL decision aid after baseline. The control group consists of unemployed people who receive support as usual from employment specialists from different organizations allocated to the control group. Primary outcomes are: cost-effectiveness of the intervention, e.g. healthcare costs, having employment, days until start of employment, independency of social security, having other forms of employment and decision making about disclosing MHI. Secondary outcomes are mental health and wellbeing, stigma and discrimination and work-related factors. Financial income data are collected via the registration systems of Dutch municipalities and Statistics Netherlands, and by questionnaires at baseline, and at 3, 6 and 12 months. DISCUSSION: If using a decision aid to decide about disclosure of MHI leads to people finding and retaining employment more often, this study will contribute to lowering healthcare and societal costs. TRIAL REGISTRATION: Netherlands Trial Register: NL7798. Registered on 4 June 2019.


Subject(s)
Disclosure , Mental Disorders/psychology , Social Stigma , Unemployment/psychology , Workplace/psychology , Cluster Analysis , Cost-Benefit Analysis , Decision Making , Humans , Longitudinal Studies , Mental Disorders/therapy , Netherlands , Randomized Controlled Trials as Topic , Surveys and Questionnaires
10.
J Environ Radioact ; 216: 106160, 2020 May.
Article in English | MEDLINE | ID: mdl-32217195

ABSTRACT

A total of 456 nuclear tests were performed from 1949 to 1989 at the Semipalatinsk Test Site (STS) in Kazakhstan, as part of the nuclear weapon test program of the USSR. To identify if radionuclides such as 137Cs, 90Sr, 241Am, 239+240Pu were associated with radioactive particles, soil samples were collected at selected contaminated sites (i.e. Experimental field, Excavation sites, Fallout plume sections, Background global fallout area, and Degelen Mountain) within the STS. A series of techniques have been applied to identify the size distributions of radionuclides, the prevalence of radioactive particles in soils, and the degree of leachability of particle associated radionuclides by different agents. In addition, selected particles were characterized non-destructively using digital autoradiography, environmental scanning electron microscopy (ESEM) and synchrotron radiation microscopic X-ray techniques. Radioactive particles were identified at all sites; large vitrified particles were identified at epicenters, and the size of particles decreased along the plume with distance from the epicenters. The radioactive particles identified varied in composition, size and leachability. In general, 137Cs, 241Am, 239+240Pu were strongly associated with solid phases (90-99%) in soils, while 90Sr exhibited much greater variability. The fraction of 90Sr present in exchangeable forms was low close to epicenters, while the extractability increased along the plume as the particle size distribution decreased. The results suggest that at least four different types of radioactive particles are present at STS: 1) Relatively large spherical particles with a shiny glazed, melted surface with internal porous structure, and surface layers enriched in transuranic elements, identified at epicenters of detonations, 2) Vitrified irregular particles probably originating from debris of nuclear device with interactions from soil components, also identified at epicenters of detonations, 3) Particles with visually unchanged structure, containing micro-inclusions of fissile materials associated with soil components, also identified at epicenters; 4) Particles with amorphous structures associated with underground detonations, identified in soil in the vicinity of the entrance of the detonation tunnels at the Degelen Mountain. These were probably formed by secondary mechanisms due to sorption and fixation of radionuclides. Thus, the present work shows that the STS should be considered an important observatory site to link particle characteristics to specific sources and to release conditions as well as to ecosystem transfer of particle associated radionuclides.


Subject(s)
Radiation Monitoring , Radioactive Fallout , Radioactivity , Ecosystem , Kazakhstan , Soil Pollutants, Radioactive
11.
Sci Adv ; 5(8): eaax1975, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31497648

ABSTRACT

Until the 19th century, lead white was the most important white pigment used in oil paintings. Lead white is typically composed of two crystalline lead carbonates: hydrocerussite [2PbCO3·Pb(OH)2] and cerussite (PbCO3). Depending on the ratio between hydrocerussite and cerussite, lead white can be classified into different subtypes, each with different optical properties. Current methods to investigate and differentiate between lead white subtypes involve invasive sampling on a microscopic scale, introducing problems of paint damage and representativeness. In this study, a 17th century painting Girl with a Pearl Earring (by Johannes Vermeer, c. 1665, collection of the Mauritshuis, NL) was analyzed with a recently developed mobile and noninvasive macroscopic x-ray powder diffraction (MA-XRPD) scanner within the project Girl in the Spotlight. Four different subtypes of lead white were identified using XRPD imaging at the macroscopic and microscopic scale, implying that Vermeer was highly discriminatory in his use of lead white.

12.
Waste Manag ; 100: 269-277, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31563840

ABSTRACT

This two paper series describes a method to develop and evaluate innovative recycling strategies for WEEE plastics. Part A presents a SWOT analysis of a new dismantling based recycling process of plastic components and the integration in an existing post-shredder separation recycling facility. Subsequently, recycling strategies are developed and the economic potential is evaluated. Part B investigates the technical feasibility of the recycling strategies. As a case study the dismantling of LCD TV plastic back cover housings is taken. First, the advantages and disadvantages of the new process and the main external factors based on the market for recycled plastics and the waste material input are discussed on industrial level. Subsequently, five recycling strategies are developed: Strategy (1) produces recycled granulates with the dismantling process for direct re-application in electronic products, strategy (2) recycles plastics for the use as carrier materials for flame retardant masterbatches, strategy (3) blends the recycled plastic with post-shredder recyclates for material upgrading, strategy (4) recycles the plastics with the post-shredder process and strategy (5) thermally treats plastics. Finally, the economic evaluation shows that the special engineering plastics used for LCD TV back covers have very high virgin prices up to 5 € per kg. The implementation of the new process indicates a significant potential for value recovery based on plastics that would otherwise be incinerated or downcycled.


Subject(s)
Electronic Waste , Flame Retardants , Electronics , Plastics , Recycling
13.
Waste Manag ; 96: 206-214, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31376966

ABSTRACT

This two paper series describes a method to develop and evaluate new recycling strategies for WEEE plastics. Part A presents a SWOT analysis that leads to five recycling strategies for the optimal integration of new dismantling based recycling processes for plastic components in an established post-shredder separation infrastructure. In this paper the technical feasibility of the strategies is demonstrated by means of LCD TV back cover housings. The component recycling is shown to produce recycled PC/ABS with phosphorous flame retardants suitable for direct re-application in electronic products. The high quality is characterized by a good mechanical and aesthetical properties as well as a recovered flammability. HIPS with brominated flame retardants was recycled to produce masterbatches. The technical feasibility of this strategy was proven by mechanical and flammability testing. However, the presence of deca-BDE requires this material to be incinerated. A combination of EU legislation research and forecasting shows that the origin of this flame retardant are TV models produced before 2008 and restricted concentrations still need to be expected for decades to come. Further, a blending strategy of HIPS/PPE is shown to improve the mechanical properties of post-shredder recycled HIPS. The evaluation of refeeding ABS/PMMA into the post-shredder recycling process of ABS indicates only partial compatibility. Further, complications due to density differences make this strategy more suitable for polymers that are already commercially recycled such as ABS and HIPS. Colour is identified as a key requirements that limits the use of WEEE plastics in high-quality products.


Subject(s)
Electronic Waste , Flame Retardants , Feasibility Studies , Plastics , Recycling
14.
Environ Sci Process Impacts ; 16(2): 306-12, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24424783

ABSTRACT

Information on Pu in environmental samples is traditionally based on the determination of the (240+239)Pu activity via Alpha Spectrometry (AS). A large number of alpha spectrometry sources (planchettes) containing radiochemically separated Pu are therefore stored worldwide and are available for further analyses. These archive samples represent a resource from which valuable information on isotopic composition of alpha emitters including Pu can be obtained. The relative abundances of Pu isotopes can be used to trace specific Pu sources and characterize the relative contributions of different Pu sources in a sample. Thus, in addition to the total (239+240)Pu activity, determination of the (240)Pu/(239)Pu ratio can provide valuable information on the nature of the Pu emitting sources. The Pu isotopic ratios can be determined by mass spectrometry techniques such as Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICPMS) or Accelerator Mass Spectrometry (AMS) that require dissolution and complete destruction of the material deposited on the planchettes. In this study Laser Ablation (LA)-quadrupole-ICP-MS has been employed for the analysis of (239)Pu/(240)Pu ratios from alpha-planchettes prepared from samples originating from the Mayak PA nuclear facility, Russia. The results are compared with data from AMS and show that the (240)Pu/(239)Pu ratios obtained by LA-ICP-MS can be utilized to distinguish weapons-grade Pu from civil reprocessing sources. Moreover, isotope ratio mapping can also be performed across the planchettes, allowing e.g. the visualization of possible inhomogeneities in the Pu-isotope distribution on their surface. Thus, this solid sample technique can be applied to extract additional information from existing archives of samples.


Subject(s)
Plutonium/analysis , Radiation Monitoring , Radioactive Pollutants/analysis , Russia , Spectrophotometry, Atomic
15.
Phys Rev Lett ; 111(20): 208302, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24289712

ABSTRACT

The degradation of colors in historical paintings affects our cultural heritage in both museums and archeological sites. Despite intensive experimental studies, the origin of darkening of one of the most ancient pigments known to humankind, vermilion (α-HgS), remains unexplained. Here, by combining many-body theoretical spectroscopy and high-resolution microscopic x-ray diffraction, we clarify the composition of the damaged paint work and demonstrate possible physicochemical processes, induced by illumination and exposure to humidity and air, that cause photoactivation of the original pigment and the degradation of the secondary minerals. The results suggest a new path for the darkening process which was never considered by previous studies and prompt a critical examination of their findings.

16.
J Environ Radioact ; 123: 63-70, 2013 Sep.
Article in English | MEDLINE | ID: mdl-22421357

ABSTRACT

The present work focuses on the use of micro-analytical techniques to demonstrate the heterogeneous distribution of radionuclides and metals in soils collected at Former Soviet Union mining sites in Central Asia. Based on digital autoradiography, radionuclides were heterogeneously distributed in soil samples collected at the abandoned uranium mining sites Kurday, Kazakhstan, Kadji Sai, Kyrgyzstan and Taboshar, Tajikistan. Using electron microscopy interfaced with X-ray microanalysis submicron - mm-sized radioactive particles and rock fragments with U, As, Se and toxic metals on the surfaces were identified in Kurday and Kadji Sai samples. Employing scanning and tomographic (3D) synchrotron radiation based micro-X-ray fluorescence (µ-SRXRF) and synchrotron radiation based micro-X-ray diffraction (µ-SRXRD) allowed us to observe the inner structure of the particles without physical sectioning. The distribution of elements in virtual crosssections demonstrated that U and a series of toxic elements were rather heterogeneously distributed also within individual radioactive TENORM particles. Compared to archived data, U in Kadji Sai particles was present as uraninite (U4O9+y or UO2+x) or Na-zippeite ((Na4(UO2)6[(OH)10(SO4)3]·4H2O), i.e. U minerals with very low solubility. The results suggested that TENORM particles can carry substantial amount of radioactivity, which can be subject to re-suspension, atmospheric transport and water transport. Thus, the potential radioecological and radioanalytical impact of radioactive particles at NORM and TENORM sites worldwide should be taken into account. The present work also demonstrates that radioecological studies should benefit from the use of advanced methods such as synchrotron radiation based techniques.


Subject(s)
Mining , Soil Pollutants, Radioactive/analysis , Uranium/analysis , Arsenic/analysis , Asia, Central , Electron Probe Microanalysis , Kazakhstan , Kyrgyzstan , Radiation Monitoring , Tajikistan , X-Ray Diffraction
17.
Bull Soc Belge Ophtalmol ; (319): 5-9, 2012.
Article in English | MEDLINE | ID: mdl-22550771

ABSTRACT

PURPOSE: To report a case of anterior segment ischemia (ASI) with rubeosis iridis after circular buckling surgery in a highly-myopic patient which was successfully treated with a second intravitreal bevacizumab injection. METHODS: Case report and review of the literature. DISCUSSION: ASI is a rare but potentially serious complication of posterior segment surgery. Finally it leads to neovascular glaucoma as a result of rubeosis iridis. An encircling band can compromise anterior segment circulation in different ways: by manipulation or disinsertion of the recti muscles, by occlusion of the vortex veins through compression or by changes in the blood supply of iris and ciliary body. This patient developed rubeosis iridis secondary to ASI. There was a remarkable regression of rubeosis iridis one month after a second intravitreal bevacizumab injection. Other case reports of bevacizumab use in neovascular glaucoma have shown clinical improvements of these patients, with intraocular pressure control and reduction of the neovascularization process. CONCLUSION: We describe a highly-myopic patient who developed ASI with rubeosis iridis after a circular buckling operation. Slit-lamp examination and gonioscopy can show very little rubeosis iridis and can be misleading. Iris fluorescein angiography is the most sensitive technique for evaluation of iris vessel abnormalities and is of considerable value in the early detection of rubeosis iridis. This report demonstrates the rapid resolution of rubeosis iridis on iris fluorescein angiography after a second intravitreal injection of bevacizumab. How long this regression will persist is unknown and repeated injections of bevacizumab may be necessary if rubeosis reappears.


Subject(s)
Anterior Eye Segment/blood supply , Antibodies, Monoclonal, Humanized/administration & dosage , Iritis/drug therapy , Iritis/etiology , Ischemia/drug therapy , Ischemia/etiology , Scleral Buckling/adverse effects , Angiogenesis Inhibitors/administration & dosage , Bevacizumab , Female , Humans , Intravitreal Injections , Middle Aged , Myopia/surgery
18.
Acc Chem Res ; 43(6): 814-25, 2010 Jun 15.
Article in English | MEDLINE | ID: mdl-20462197

ABSTRACT

Often, just micrometers below a painting's surface lies a wealth of information, both with Old Masters such as Peter Paul Rubens and Rembrandt van Rijn and with more recent artists of great renown such as Vincent Van Gogh and James Ensor. Subsurface layers may include underdrawing, underpainting, and alterations, and in a growing number of cases conservators have discovered abandoned compositions on paintings, illustrating artists' practice of reusing a canvas or panel. The standard methods for studying the inner structure of cultural heritage (CH) artifacts are infrared reflectography and X-ray radiography, techniques that are optionally complemented with the microscopic analysis of cross-sectioned samples. These methods have limitations, but recently, a number of fundamentally new approaches for fully imaging the buildup of hidden paint layers and other complex three-dimensional (3D) substructures have been put into practice. In this Account, we discuss these developments and their recent practical application with CH artifacts. We begin with a tabular summary of 14 IR- and X-ray-based imaging methods and then continue with a discussion of each technique, illustrating CH applications with specific case studies. X-ray-based tomographic and laminographic techniques can be used to generate 3D renditions of artifacts of varying dimensions. These methods are proving invaluable for exploring inner structures, identifying the conservation state, and postulating the original manufacturing technology of metallic and other sculptures. In the analysis of paint layers, terahertz time-domain spectroscopy (THz-TDS) can highlight interfaces between layers in a stratigraphic buildup, whereas macrosopic scanning X-ray fluorescence (MA-XRF) has been employed to measure the distribution of pigments within these layers. This combination of innovative methods provides topographic and color information about the micrometer depth scale, allowing us to look "into" paintings in an entirely new manner. Over the past five years, several new variants of traditional IR- and X-ray-based imaging methods have been implemented by conservators and museums, and the first reports have begun to emerge in the primary research literature. Applying these state-of-the-art techniques in a complementary fashion affords a more comprehensive view of paintings and other artworks.

19.
Anal Bioanal Chem ; 395(7): 1977-85, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19760192

ABSTRACT

In favourable conditions of low temperature and low oxygen concentration, archaeological waterlogged wooden artefacts, such as shipwrecks, can survive with a good state of preservation. Nevertheless, anaerobic bacteria can considerably degrade waterlogged wooden objects with a significant loss in polysaccharidic components. Due to these decay processes, wood porosity and water content increase under ageing. In such conditions, the conservation treatments of archaeological wooden artefacts often involve the replacement of water with substances which fill the cavities and help to prevent collapse and stress during drying. The treatments are very often expensive and technically difficult, and their effectiveness very much depends on the chemical and physical characteristics of the substances used for impregnation. Also important are the degree of cavity-filling, penetration depth and distribution in the structure of the wood. In this study, the distribution in wood cavities of some mixtures based on polyethylene glycols and colophony, used for the conservation of waterlogged archaeological wood, was investigated using synchrotron radiation X-ray computed microtomography (SR-microCT). This non-destructive imaging technique was useful for the study of the degraded waterlogged wood and enabled us to visualise the morphology of the wood and the distribution of the materials used in the wood treatments. The study has shown how deposition is strictly related to the dimension of the wooden cavities. The work is currently proceeding with the comparison of synchrotron observations with the data of the solutions viscosity and with those of the properties imparted to the wood by the treatments.


Subject(s)
Archaeology/methods , Electron Microscope Tomography/methods , Synchrotrons , Water , Wood/chemistry , Electron Microscope Tomography/instrumentation , History, Ancient , Wood/history
20.
J Environ Radioact ; 100(4): 301-7, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19216013

ABSTRACT

A combination of synchrotron radiation based X-ray microscopic techniques (mu-XRF, mu-XANES, mu-XRD) applied on single depleted uranium (DU) particles and semi-bulk leaching experiments has been employed to link the potential bioavailability of DU particles to site-specific particle characteristics. The oxidation states and crystallographic forms of U in DU particles have been determined for individual particles isolated from selected samples collected at different sites in Kosovo and Kuwait that were contaminated by DU ammunition during the 1999 Balkan conflict and the 1991 Gulf war. Furthermore, small soil or sand samples heavily contaminated with DU particles were subjected to simulated gastrointestinal fluid (0.16 M HCl) extractions. Characteristics of DU particles in Kosovo soils collected in 2000 and in Kuwait soils collected in 2002 varied significantly depending on the release scenario and to some extent on weathering conditions. Oxidized U (+6) was determined in large, fragile and bright yellow DU particles released during fire at a DU ammunition storage facility and crystalline phases such as schoepite (UO(3).2.25H(2)O), dehydrated schoepite (UO(3).0.75H(2)O) and metaschoepite (UO(3).2.0H(2)O) were identified. As expected, these DU particles were rapidly dissolved in 0.16 M HCl (84 +/- 3% extracted after 2 h) indicating a high degree of potential mobility and bioavailability. In contrast, the 2 h extraction of samples contaminated with DU particles originating either from corrosion of unspent DU penetrators or from impacted DU ammunition appeared to be much slower (20-30%) as uranium was less oxidized (+4 to +6). Crystalline phases such as UO(2), UC and metallic U or U-Ti alloy were determined in impacted DU particles from Kosovo and Kuwait, while the UO(2,34) phase, only determined in particles from Kosovo, could reflect a more corrosive environment. Although the results are based on a limited number of DU particles, they indicate that the structure and extractability of DU particles released from similar sources (metallic U penetrators) will depend on the release scenarios (fire, impact) and to some extent environmental conditions. However, most of the DU particles (73-96%) in all investigated samples were dissolved in 0.16 M HCl after one week indicating that a majority of the DU material is bioaccessible.


Subject(s)
Soil/analysis , Uranium/chemistry , Weapons , Biological Availability , Chemistry, Analytic/methods , Electron Probe Microanalysis , Gulf War , Kuwait , Oxidation-Reduction , Solubility , Synchrotrons , Yugoslavia
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