26
|
Saarinen K, Karjalainen A, Martikainen R, Uitti J, Tammilehto L, Klaukka T, Kurppa K. Prevalence of work-aggravated symptoms in clinically established asthma. Eur Respir J 2003; 22:305-9. [PMID: 12952265 DOI: 10.1183/09031936.03.00100102] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This population-based cross-sectional survey assessed the prevalence of work-aggravated asthma symptoms and the effect of the work environment on the aggravation of symptoms of established asthma. A questionnaire was sent to 2,613 persons (aged 20-65 yrs) with asthma. The analyses were restricted to the 969 respondents who were currently employed. The effect of occupational exposure on the aggravation of asthma symptoms at work was assessed according to both self-reported and expert-evaluated exposure. Approximately 21% of the respondents reported work-aggravated asthma symptoms at least weekly during the past month. The prevalence of those with work-aggravated symptoms increased by age, self-reported occupational exposure to dusts, abnormal temperatures or poor indoor air quality, physically strenuous work, and chemicals, and expert-evaluated probability of daily occupational exposure to airborne dusts, gases or fumes. Aggravation of asthma symptoms at work is common among employed adults with asthma. Both self-reported and expert-evaluated exposure to dusts, abnormal temperatures or poor indoor air quality, physically strenuous work, and chemicals explained the significant worsening of symptoms. The findings suggest a marked role of the work environment in the aggravation of symptoms of established asthma.
Collapse
|
27
|
Hautakangas S, Oila J, Alatalo M, Saarinen K, Liszkay L, Seghier D, Gislason HP. Vacancy defects as compensating centers in Mg-doped GaN. PHYSICAL REVIEW LETTERS 2003; 90:137402. [PMID: 12689324 DOI: 10.1103/physrevlett.90.137402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2002] [Indexed: 05/24/2023]
Abstract
We apply positron annihilation spectroscopy to identify V(N)-Mg(Ga) complexes as native defects in Mg-doped GaN. These defects dissociate in postgrowth annealings at 500-800 degrees C. We conclude that V(N)-Mg(Ga) complexes contribute to the electrical compensation of Mg as well as the activation of p-type conductivity in the annealing. The observation of V(N)-Mg(Ga) complexes confirms that vacancy defects in either the N or Ga sublattice are abundant in GaN at any position of the Fermi level during growth, as predicted previously by theoretical calculations.
Collapse
|
28
|
Karjalainen A, Martikainen R, Klaukka T, Saarinen K, Uitti J. Risk of asthma among Finnish patients with occupational rhinitis. Chest 2003; 123:283-8. [PMID: 12527633 DOI: 10.1378/chest.123.1.283] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVES To determine the risk of asthma among patients with occupationally induced rhinitis. DESIGN Patients with confirmed occupational rhinitis were followed for asthma incidence through register linkage. Patients with other occupational diseases were used as a reference population. SUBJECTS Patients entered into the Finnish Register of Occupational Diseases in from 1988 to 1999 for occupational rhinitis (n = 3,637) or other occupational disease (n = 31,457) were observed until December 31, 2000, through two national registers of individuals who were eligible for the reimbursement of asthma medication and the Population Register Center. METHODS Incidence rates of asthma were calculated, and a log-linear model, adjusted for age, gender, and occupation, was used to estimate the relative risks (RRs) of asthma among those with occupational rhinitis compared to those with other occupational diseases. RESULTS There were 420 and 972 incident cases of asthma, respectively, among those with occupational rhinitis and the reference population. The crude RR of asthma was 4.8 (95% confidence interval [CI], 4.3 to 5.4) for all patients with occupational rhinitis, 5.4 (95% CI, 4.8 to 6.2) for those with occupational rhinitis accepted for compensation, and 3.7 (95% CI, 3.1 to 4.5) for patients with unaccepted occupational rhinitis. The RR varied according to occupation and was the highest among farmers and wood workers, both groups having a sevenfold risk. The risk was especially high during the year following notification, but a roughly threefold risk persisted several years thereafter. CONCLUSIONS Patients with occupationally induced rhinitis have a high risk of asthma, but further studies are needed to establish the effect of preventive interventions.
Collapse
|
29
|
Karjalainen A, Martikainen R, Oksa P, Saarinen K, Uitti J. Incidence of asthma among Finnish construction workers. J Occup Environ Med 2002; 44:752-7. [PMID: 12185796 DOI: 10.1097/00043764-200208000-00010] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We wanted to explore the risk of asthma among male workers of the construction industry. All Finnish male construction industry workers and all those employed in administrative work were followed for asthma incidence through a register linkage in 1986 through 1998. Age-adjusted relative risks (RR) were estimated for 24 construction occupations. The risk was increased in nearly all construction occupations studied, but it was highest among welders and flame cutters (RR 2.34), asphalt roofing workers (RR 2.04), plumbers (RR 1.90), and brick layers and tile setters (RR 1.83). Only 45 (2%) of the cases of asthma among construction workers had been recognized as occupational asthma. Construction industry workers have an increased risk of adult-onset persistent asthma and cases of occupational asthma caused by well-established causative agents have only a minor contribution to this overall asthma excess.
Collapse
|
30
|
Ranki V, Nissilä J, Saarinen K. Formation of vacancy-impurity complexes by kinetic processes in highly As-doped Si. PHYSICAL REVIEW LETTERS 2002; 88:105506. [PMID: 11909372 DOI: 10.1103/physrevlett.88.105506] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2001] [Indexed: 05/23/2023]
Abstract
Positron annihilation experiments have been applied to verify the formation mechanism of electrically inactive vacancy-impurity clusters in highly n-type Si. We show that the migration of V-As pairs at 450 K leads to the formation of V-As2 complexes, which in turn convert to stable V-As3 defects at 700 K. These processes manifest the formation of V-As3 as the dominant vacancy-impurity cluster in highly n-type Si. They further explain the electrical deactivation and clustering of As in epitaxial or ion-implanted Si during postgrowth heat treatment at 700 K.
Collapse
|
31
|
Abstract
We consider the scattering of light by single wood fibers both theoretically and experimentally. We describe the size and the shape distributions and the internal structure and chemical composition of the wood fibers. We have modeled the random shape of the hollow, cylindrical wood fiber by using multivariate lognormal statistics. We have computed wood-fiber absorption and scattering cross sections, asymmetry parameters, and scattering phase matrices in the ray-optics approximation. Finally, we have provided experimental results from angular scattering measurements for wood fibers and present what we believe is the first comparison between these measurements and ray-optics computations for Gaussian random wood-fiber models. In spite of the complicated internal structure of the wood fiber, our model together with the ray-optics treatment explains the scattering measurements surprisingly well.
Collapse
|
32
|
Alanko K, Tuomi T, Vanhanen M, Pajari-Backas M, Kanerva L, Havu K, Saarinen K, Bruynzeel DP. Occupational IgE-mediated allergy to Tribolium confusum (confused flour beetle). Allergy 2000; 55:879-82. [PMID: 11003453 DOI: 10.1034/j.1398-9995.2000.00572.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND We report on IgE-mediated allergy in a worker caused by Tribolium confusum (confused flour beetle). These beetles lived in the "old" flour to which he was exposed in his work. CASE REPORT A 35-year-old, nonatopic mechanic in a rye crispbread factory developed rhinitis, conjunctivitis, and asthmatic symptoms, as well as urticaria on his wrists, lower arms, hands, neck, and face, during the maintenance and repair of machines contaminated by flour. This flour had been in and on the machines for a long time, and it contained small beetles. The patient did not suffer any symptoms when handling fresh, clean flour. RESULTS Skin prick tests with standard environmental allergens, storage mites, enzymes, flours, and molds were negative. A prick test with flour from the machines gave a 10-mm reaction. An open application of the same flour caused urticarial whealing on the exposed skin. Prick tests with fresh flour from the factory were negative. A prick test with minced T. confusum from the flour in the machines gave a 7-mm reaction. Histamine hydrochloride 10 mg/ml gave a 7-mm reaction. Specific serum IgE antibodies to T. confusum were elevated at 17.2 kU/l. Prick tests with the flour from the machines were negative in five control patients. CONCLUSIONS The patient had occupational contact urticaria, rhinitis, conjunctivitis, and asthmatic symptoms from exposure to flour. His symptoms were caused by immediate allergy to the beetle T. confusum. Immediate allergy to this beetle has rarely been reported in connection with respiratory symptoms, but it may be more common. Contact urticaria from this source has not been reported before.
Collapse
|
33
|
Saarinen K, Lestringant GG, Masouye I, Frossard PM. Actinic damage and squamous cell carcinoma in sun-exposed skin affected by vitiligo. Br J Dermatol 2000; 143:219-21. [PMID: 10886181 DOI: 10.1046/j.1365-2133.2000.03636.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
34
|
Saarinen K, Swan H, Kainulainen K, Toivonen L, Viitasalo M, Kontula K. Molecular genetics of the long QT syndrome: two novel mutations of the KVLQT1 gene and phenotypic expression of the mutant gene in a large kindred. Hum Mutat 2000; 11:158-65. [PMID: 9482580 DOI: 10.1002/(sici)1098-1004(1998)11:2<158::aid-humu9>3.0.co;2-f] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
At least three different gene loci were recently shown to account for the long QT syndrome (LQTS), a monogenic disorder with altered myocardial repolarization and occurrence of life-threatening cardiac arrhythmias. We screened 44 unrelated probands for mutations of the gene encoding the cardiac potassium channel KVLQT1 using single-strand conformational polymorphism (SSCP) and subsequent DNA sequencing. Two different mutations, T182I and D188N, were identified in two separate pedigrees. Cosegregation of the mutation with the disease phenotype was evident in both families. No mutations were identified at codon 212, previously suggested to represent a mutational hot spot of the KVLQT1 channel, in any of the 44 probands. The large pedigree with the D188N mutation (30 affected and 43 nonaffected individuals) permitted an analysis of expression of the mutant gene in its documented carriers. Although the mean (+/-SD) QTc interval was markedly longer in affected (484+/-38 ms) than in nonaffected individuals (406+/-27 ms, P < 0.001), there was a marked overlapping of individual values in these two groups. QTc values in symptomatic and asymptomatic carriers of the mutant gene were not significantly different. In conclusion, we have identified two novel mutations of the KVLQT1 component of a cardiac potassium channel. Our data support the functional significance of the pore-S6 domain of this membrane protein and emphasize the diagnostic usefulness of DNA analyses in families with LQTS.
Collapse
|
35
|
Saarinen K, Kivistö K, Blomberg K, Punnonen K, Leino L. Time-resolved fluorometric assay for leukocyte adhesion using a fluorescence enhancing ligand. J Immunol Methods 2000; 236:19-26. [PMID: 10699576 DOI: 10.1016/s0022-1759(99)00233-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A new 96-well microtiter plate, time-resolved fluorometric assay was developed to measure leukocyte adhesion in vitro. The assay is based on loading leukocytes with a fluorescence enhancing ligand 2,2':6', 2"-terpyridine-6,6"-dicarboxylic acid (TDA), which in its acetoxymethyl ester form readily diffuses through the cell membrane. After hydrolysis by nonspecific intracellular esterases, the impermeable TDA accumulates inside the cells. When the TDA-labeled adherent leukocytes are lysed, the ligand is released and reacts with europium present in the lysis solution to produce a highly fluorescent and stable chelate. The fluorescence signal can be measured by time-resolved fluorometry and correlates directly with the number of adherent cells. In this study, we have optimized both the TDA-labeling and adhesion assay conditions in isolated human neutrophils. Furthermore, we have compared the assay with a traditional microscopic counting method. This time-resolved fluorometric assay provides a rapid, reproducible and convenient method for the routine analysis of leukocyte adhesion.
Collapse
|
36
|
Leino L, Saarinen K, Kivistö K, Koulu L, Jansen CT, Punnonen K. Systemic suppression of human peripheral blood phagocytic leukocytes after whole-body UVB irradiation. J Leukoc Biol 1999; 65:573-82. [PMID: 10331484 DOI: 10.1002/jlb.65.5.573] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We examined systemic effects of whole-body UVB irradiation on human peripheral blood phagocytes. We found that 24 h after a single erythemal dose of UVB radiation two phagocyte functions, adhesion and phagocytosis, were reduced by 50%. This functional suppression was accompanied by a significant decrease in the expression of complement receptors (CR1 and CR3) and IgG Fc receptors (FcRII and FcRIII). The greatest reduction (47%) was observed in CR3, which is important for both adhesion and phagocytosis. A kinetic analysis showed that both CR1 and CR3 levels started to decrease 15 min after the UVB exposure, reaching the lowest levels at 4.5- and 24-h time points, respectively. The down-modulation of CRs after whole-body UVB exposure was not due to a defective receptor synthesis or translocation from internal stores to plasma membrane because the maximal CR levels in stimulated cells were not affected by UVB. No change in the serum soluble ICAM-1 was detected after UVB, which rules out CD1 1b epitope masking by sICAM-1. UVB did not release low-receptor-density myeloid progenitor cells from storage pools into circulation. Interleukin 10, a mediator of UVB-induced immunosuppression, was unable to modulate CR expression in vitro. When seven suberythemal whole-body UVB exposures were given repeatedly within 2 weeks, a significant decrease in CR expression was seen, which was greatest after three irradiations. Our data suggest that an exposure to UVB has systemic effects in humans which, possibly due to the down-modulation of preexisting cell-surface receptors, suppress some important functions of circulating phagocytic cells.
Collapse
|
37
|
Swan H, Saarinen K, Kontula K, Toivonen L, Viitasalo M. Evaluation of QT interval duration and dispersion and proposed clinical criteria in diagnosis of long QT syndrome in patients with a genetically uniform type of LQT1. J Am Coll Cardiol 1998; 32:486-91. [PMID: 9708480 DOI: 10.1016/s0735-1097(98)00248-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES This study investigated the ability of QT duration, QT dispersion (QTD) and clinical diagnostic criteria to correctly identify genetically documented LQT1 type long QT syndrome (LQTS) patients, and to separate symptomatic and asymptomatic LQT1 patients. BACKGROUND Ventricular repolarization has played an essential role both in diagnosis and risk assessment of LQTS. Today, molecular genetic techniques permit unequivocal identification of many LQTS patients. METHODS QT interval and QTD in 12 symptomatic and 18 asymptomatic LQT1 patients and their 43 healthy relatives were evaluated. The sensitivity and specificity of upper normal limits of QT interval, two QT interval adjustment methods (Bazett's and Fridericia's formulas), and the proposed clinical criteria for LQTS were assessed. Occurrence of a mutant (D188N) KVLQT1 gene was considered as the basis of classification into affected and nonaffected individuals. RESULTS Diagnostic sensitivity and specificity values were 90% and 88% using Bazett's formula, and 80% and 100% using Fridericia's cubic root formula or upper normal limits for QT interval. Suggested diagnostic criteria for LQTS reached 100% specificity, but 47% of the DNA-documented LQT1 patients were classified into the category of low or intermediate probability of LQTS. QT interval and heart rate did not differ between symptomatic (464 +/- 47 ms, 70 +/- 9 min(-1)) and asymptomatic 460 +/- 41 ms, 65 +/- 13 min(-1)) LQT1 patients. QTD was increased in symptomatic LQT1 patients compared to unaffected relatives (66 +/- 48 vs. 37 +/- 15 ms, p = 0.02), but symptomatic patients LQT1 did not differ from asymptomatic (45 +/- 19 ms). CONCLUSIONS Not all LQT1 patients can be distinguished from healthy relatives by assessment of QT duration or clinical criteria. Presence of LQT1 gene can carry the risk of cardiac events even with no or only marginal prolongation of QT interval.
Collapse
|
38
|
Dlubek G, Saarinen K, Fretwell HM. The temperature dependence of the local free volume in polyethylene and polytetrafluoroethylene: A positron lifetime study. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1099-0488(19980715)36:9<1513::aid-polb9>3.0.co;2-k] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
39
|
Hurttia H, Saarinen K, Leino L. Increased adhesion of peripheral blood neutrophils from patients with localized juvenile periodontitis. J Periodontal Res 1998; 33:292-7. [PMID: 9777596 DOI: 10.1111/j.1600-0765.1998.tb02202.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Adhesion of peripheral blood neutrophils from 5 patients with localized juvenile periodontitis (LJP) and age- and gender-matched healthy controls was measured using a semi-automated 96-well microtiter plate assay method. Both unstimulated and formyl-methionyl-leucyl-phenylalanine (FMLP, 10-1000 nM)-stimulated neutrophils from LJP patients showed in general higher adhesion than did their controls. After 15-60 min incubation with 100 and 1000 nM FMLP the numbers of adherent cells were significantly (p < 0.05), 2.1-2.6-fold higher in LJP patients than in controls. Neutrophils from these LJP patients showed also enhanced respiratory burst activity in response to unopsonized zymosan stimulation. To test whether a decrease in intracellular diacylglycerol (DAG) kinase activity could account for the increased neutrophil adhesion of LJP patients normal neutrophils were treated with R59949 (10 microM), a DAG-kinase inhibitor. Both unstimulated and FMLP-stimulated normal neutrophils showed significantly (p < 0.05) enhanced adhesion after R59949-treatment. Taken together, our data indicate that neutrophils from the 5 LJP patients investigated here exhibit 2 parallel hyperactivities, namely increased adhesion and enhanced production of reactive oxygen species. Furthermore, our present and previous (Hurttia et al., J Periodont Res 1997; 32: 401-407) results suggest that the observed neutrophil functional abnormalities in some LJP patients may be associated with decreased cellular DAG-kinase activity. It is proposed that the hyperadherent and -active neutrophils may promote the development of LJP by causing tissue damage in the periodontium.
Collapse
|
40
|
Swan H, Vutasato M, Saarinen K, Kontula K, Toivonen L. A mutation in KVLQT1 causes decreased sinus rate without evidence of autonomic nervous abnormalities. J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(98)81478-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
41
|
Dlubek G, Saarinen K. A positron lifetime and Doppler-broadening study of positron states and free volume in polyethylene. J Radioanal Nucl Chem 1996. [DOI: 10.1007/bf02056389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
42
|
Laine T, Saarinen K, Mäkinen J, Hautojärvi P, Corbel C, Pfeiffer LN, Citrin PH. Observation of compensating Ga vacancies in highly Si-doped GaAs. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:R11050-R11053. [PMID: 9984983 DOI: 10.1103/physrevb.54.r11050] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
43
|
Saarinen K, Laine T, Skog K, Mäkinen J, Hautojärvi P, Rakennus K, Uusimaa P, Salokatve A, Pessa M. Identification of the Native Vacancy Defects in Both Sublattices of ZnSx Se1-x by Positron Annihilation. PHYSICAL REVIEW LETTERS 1996; 77:3407-3410. [PMID: 10062212 DOI: 10.1103/physrevlett.77.3407] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
44
|
Alatalo M, Barbiellini B, Hakala M, Kauppinen H, Korhonen T, Puska MJ, Saarinen K, Hautojärvi P, Nieminen RM. Theoretical and experimental study of positron annihilation with core electrons in solids. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:2397-2409. [PMID: 9986086 DOI: 10.1103/physrevb.54.2397] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
45
|
Laine T, Mäkinen J, Saarinen K, Hautojärvi P, Corbel C, Fille ML, Gibart P. Vacancylike structure of the DX center in Te-doped AlxGa1-xAs. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:11025-11033. [PMID: 9982675 DOI: 10.1103/physrevb.53.11025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
46
|
Kuisma S, Saarinen K, Hautojärvi P, Corbel C, LeBerre C. Optical processes related to arsenic vacancies in semi-insulating GaAs studied by positron spectroscopy. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:9814-9830. [PMID: 9982542 DOI: 10.1103/physrevb.53.9814] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
47
|
Kuisma S, Saarinen K, Hautojärvi P, Corbel C. Infrared absorption related to the metastable state of arsenic antisite defects in electron-irradiated GaAs. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:R7588-R7591. [PMID: 9982273 DOI: 10.1103/physrevb.53.r7588] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
48
|
Mäkinen J, Laine T, Partanen J, Saarinen K, Hautojärvi P, Tappura K, Hakkarainen T, Asonen H, Pessa M, Kauppinen JP, Vänttinen K, Paalanen MA, Likonen J. Donor levels and the microscopic structure of the DX center in n-type Si-doped AlxGa0.51-xIn0.49P grown by molecular-beam epitaxy. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:7851-7862. [PMID: 9982235 DOI: 10.1103/physrevb.53.7851] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
49
|
Saarinen K, Seitsonen AP, Hautojärvi P, Corbel C. Introduction and recovery of point defects in electron-irradiated Te- and Si-doped GaAs studied by positron lifetime spectroscopy. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:10932-10946. [PMID: 9980192 DOI: 10.1103/physrevb.52.10932] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
50
|
Corbel C, Saarinen K, Kuisma S, Hautojärvi P, Fornari R. Evidence of two kinds of acceptors in undoped semi-insulating GaAs: Positron trapping at gallium vacancies and negative ions. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:8112-8120. [PMID: 9979809 DOI: 10.1103/physrevb.52.8112] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|