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1.	Abbafati, Cristiana, et al. (author) 2020 Journal article (peer-reviewed)
2.	Adcox, K, et al. (author) PHENIX detector overview 2003 In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 469-479 Journal article (peer-reviewed)abstract The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions. A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon. Designing for the needs of the heavy-ion and polarized-proton programs has produced a detector with unparalleled capabilities. PHENIX measures electron and muon pairs, photons, and hadrons with excellent energy and momentum resolution. The detector consists of a large number of subsystems that are discussed in other papers in this volume. The overall design parameters of the detector are presented. (C) 2002 Elsevier Science B.V. All rights reserved.
3.	Adler, SS, et al. (author) PHENIX on-line systems 2003 In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 560-592 Journal article (peer-reviewed)abstract The PHENIX On-Line system takes signals from the Front End Modules (FEM) on each detector subsystem for the purpose of generating events for physics analysis. Processing of event data begins when the Data Collection Modules (DCM) receive data via fiber-optic links from the FEMs. The DCMs format and zero suppress the data and generate data packets. These packets go to the Event Builders (EvB) that assemble the events in final form. The Level-1 trigger (LVL1) generates a decision for each beam crossing and eliminates uninteresting events. The FEMs carry out all detector processing of the data so that it is delivered to the DCMs using a standard format. The FEMs also provide buffering for LVL1 trigger processing and DCM data collection. This is carried out using an architecture that is pipelined and deadtimeless. All of this is controlled by the Master Timing System (MTS) that distributes the RHIC clocks. A Level-2 trigger (LVL2) gives additional discrimination. A description of the components and operation of the PHENIX On-Line system is given and the solution to a number of electronic infrastructure problems are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
4.	Carmody, C., et al. (author) Ion-implanted In0.53Ga0.47As for ultrafast optoelectronic applications 2003 In: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 82:22, s. 3913-3915 Journal article (peer-reviewed)abstract Undoped In0.53Ga0.47As epilayers were implanted with 2- MeV Fe+ ions at doses of 1x10(15) and 1x10(16) cm(-2) at room temperature and annealed at temperatures between 500 and 800 degreesC. Hall-effect measurements show that after annealing, layers with resistivities on the order of 10(5) Omega/square can be achieved. Carrier lifetimes as short as 300 fs are observed for samples annealed at 500 and 600 degreesC. For higher annealing temperatures, characteristic times of the optical response are on the order of a few picoseconds.
5.	Carmody, C., et al. (author) Structural, electrical, and optical analysis of ion implanted semi-insulating InP 2004 In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 95:2, s. 477-482 Journal article (peer-reviewed)abstract Semi-insulating InP was implanted with MeV P, As, Ga, and In ions, and the resulting evolution of structural properties with increased annealing temperature was analyzed using double crystal x-ray diffractometry and cross sectional transmission electron microscopy. The types of damage identified are correlated with scanning spreading resistance and scanning capacitance measurements, as well as with previously measured Hall effect and time resolved photoluminescence results. We have identified multiple layers of conductivity in the samples which occur due to the nonuniform damage profile of a single implant. Our structural studies have shown that the amount and type of damage caused by implantation does not scale with implant ion atomic mass.
6.	Carmody, C., et al. (author) Ultrafast carrier trapping and recombination in highly resistive ion implanted InP 2003 In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 94:2, s. 1074-1078 Journal article (peer-reviewed)abstract MeV P+ implanted and annealed p-InP, and Fe+ implanted and annealed semi-insulating InP have both been shown to produce the high resistivity, good mobility, and ultrafast optical response desired for ultrafast photodetectors. Hall effect measurements and time resolved photoluminescence were used to analyze the electrical and optical features of such implanted materials. Low temperature annealing was found to yield the fastest response times-130 fs for Fe+ implanted and 400 fs for P+ implanted InP, as well as resistivities of the order similar to10(6) Omega/square. It was found that the electrical activation of Fe-related centers, useful for achieving high resistivities in Fe+ implanted semi-insulating InP, was not fully realized at the annealing temperatures chosen to produce the fastest optical response. Implanting p-InP in the dose regime where type conversion occurs, and subsequent annealing at 500degreesC, produces high resistivities and ultrafast carrier trapping times that are only marginally dose dependent.
7.	Feigin, Valery L., et al. (author) Global, regional, and national burden of stroke and its risk factors, 1990-2019 : a systematic analysis for the Global Burden of Disease Study 2019 2021 In: Lancet Neurology. - : Elsevier. - 1474-4422 .- 1474-4465. ; 20:10, s. 795-820 Journal article (peer-reviewed)abstract Background Regularly updated data on stroke and its pathological types, including data on their incidence, prevalence, mortality, disability, risk factors, and epidemiological trends, are important for evidence-based stroke care planning and resource allocation. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) aims to provide a standardised and comprehensive measurement of these metrics at global, regional, and national levels. Methods We applied GBD 2019 analytical tools to calculate stroke incidence, prevalence, mortality, disability-adjusted life-years (DALYs), and the population attributable fraction (PAF) of DALYs (with corresponding 95% uncertainty intervals [UIs]) associated with 19 risk factors, for 204 countries and territories from 1990 to 2019. These estimates were provided for ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage, and all strokes combined, and stratified by sex, age group, and World Bank country income level. Findings In 2019, there were 12.2 million (95% UI 11.0-13.6) incident cases of stroke, 101 million (93.2-111) prevalent cases of stroke, 143 million (133-153) DALYs due to stroke, and 6.55 million (6.00-7.02) deaths from stroke. Globally, stroke remained the second-leading cause of death (11.6% [10.8-12.2] of total deaths) and the third-leading cause of death and disability combined (5.7% [5.1-6.2] of total DALYs) in 2019. From 1990 to 2019, the absolute number of incident strokes increased by 70.0% (67.0-73.0), prevalent strokes increased by 85.0% (83.0-88.0), deaths from stroke increased by 43.0% (31.0-55.0), and DALYs due to stroke increased by 32.0% (22.0-42.0). During the same period, age-standardised rates of stroke incidence decreased by 17.0% (15.0-18.0), mortality decreased by 36.0% (31.0-42.0), prevalence decreased by 6.0% (5.0-7.0), and DALYs decreased by 36.0% (31.0-42.0). However, among people younger than 70 years, prevalence rates increased by 22.0% (21.0-24.0) and incidence rates increased by 15.0% (12.0-18.0). In 2019, the age-standardised stroke-related mortality rate was 3.6 (3.5-3.8) times higher in the World Bank low-income group than in the World Bank high-income group, and the age-standardised stroke-related DALY rate was 3.7 (3.5-3.9) times higher in the low-income group than the high-income group. Ischaemic stroke constituted 62.4% of all incident strokes in 2019 (7.63 million [6.57-8.96]), while intracerebral haemorrhage constituted 27.9% (3.41 million [2.97-3.91]) and subarachnoid haemorrhage constituted 9.7% (1.18 million [1.01-1.39]). In 2019, the five leading risk factors for stroke were high systolic blood pressure (contributing to 79.6 million [67.7-90.8] DALYs or 55.5% [48.2-62.0] of total stroke DALYs), high body-mass index (34.9 million [22.3-48.6] DALYs or 24.3% [15.7-33.2]), high fasting plasma glucose (28.9 million [19.8-41.5] DALYs or 20.2% [13.8-29.1]), ambient particulate matter pollution (28.7 million [23.4-33.4] DALYs or 20.1% [16.6-23.0]), and smoking (25.3 million [22.6-28.2] DALYs or 17.6% [16.4-19.0]). Interpretation The annual number of strokes and deaths due to stroke increased substantially from 1990 to 2019, despite substantial reductions in age-standardised rates, particularly among people older than 70 years. The highest age-standardised stroke-related mortality and DALY rates were in the World Bank low-income group. The fastest-growing risk factor for stroke between 1990 and 2019 was high body-mass index. Without urgent implementation of effective primary prevention strategies, the stroke burden will probably continue to grow across the world, particularly in low-income countries.
8.	Li, Z-F, et al. (author) Determination of carrier-transfer length from side-wall quantum well to quantum wire by micro-photoluminescence scanning 2003 In: Journal of Electronic Materials. - : Springer Science Business Media. - 0361-5235 .- 1543-186X. ; 32:8, s. 913-916 Journal article (peer-reviewed)abstract Micro-photoluminescence (mu-PL) line scanning across a single V-groove, GaAs/AlGaAs quantum wire (QWR) has been performed at room temperature, revealing a clear spatial-dependence of the PL. After fitting each PL spectrum by multi-Gaussian line shapes, intensity profiles of each PL component from confined structures have been obtained as functions of the scanning position. The PL quenching of a side-wall quantum well (SQWL) has been recognized in a certain area in the vicinity of the QWR and is interpreted by carrier transfer into the QWR within effective transfer length. By simulating the carrier-transfer process from SQWL to QWR as a convolution of a step function for carrier distribution and a Gaussian function for exciting laser irradiance, the effective transfer length of about 1.8+/-0.3 mum has, therefore, been concluded.
9.	Micah, Angela E., et al. (author) Tracking development assistance for health and for COVID-19 : a review of development assistance, government, out-of-pocket, and other private spending on health for 204 countries and territories, 1990-2050 2021 In: The Lancet. - : Elsevier. - 0140-6736 .- 1474-547X. ; 398:10308, s. 1317-1343 Research review (peer-reviewed)abstract Background The rapid spread of COVID-19 renewed the focus on how health systems across the globe are financed, especially during public health emergencies. Development assistance is an important source of health financing in many low-income countries, yet little is known about how much of this funding was disbursed for COVID-19. We aimed to put development assistance for health for COVID-19 in the context of broader trends in global health financing, and to estimate total health spending from 1995 to 2050 and development assistance for COVID-19 in 2020. Methods We estimated domestic health spending and development assistance for health to generate total health-sector spending estimates for 204 countries and territories. We leveraged data from the WHO Global Health Expenditure Database to produce estimates of domestic health spending. To generate estimates for development assistance for health, we relied on project-level disbursement data from the major international development agencies' online databases and annual financial statements and reports for information on income sources. To adjust our estimates for 2020 to include disbursements related to COVID-19, we extracted project data on commitments and disbursements from a broader set of databases (because not all of the data sources used to estimate the historical series extend to 2020), including the UN Office of Humanitarian Assistance Financial Tracking Service and the International Aid Transparency Initiative. We reported all the historic and future spending estimates in inflation-adjusted 2020 US$, 2020 US$ per capita, purchasing-power parity-adjusted US$ per capita, and as a proportion of gross domestic product. We used various models to generate future health spending to 2050. Findings In 2019, health spending globally reached $8. 8 trillion (95% uncertainty interval [UI] 8.7-8.8) or $1132 (1119-1143) per person. Spending on health varied within and across income groups and geographical regions. Of this total, $40.4 billion (0.5%, 95% UI 0.5-0.5) was development assistance for health provided to low-income and middle-income countries, which made up 24.6% (UI 24.0-25.1) of total spending in low-income countries. We estimate that $54.8 billion in development assistance for health was disbursed in 2020. Of this, $13.7 billion was targeted toward the COVID-19 health response. $12.3 billion was newly committed and $1.4 billion was repurposed from existing health projects. $3.1 billion (22.4%) of the funds focused on country-level coordination and $2.4 billion (17.9%) was for supply chain and logistics. Only $714.4 million (7.7%) of COVID-19 development assistance for health went to Latin America, despite this region reporting 34.3% of total recorded COVID-19 deaths in low-income or middle-income countries in 2020. Spending on health is expected to rise to $1519 (1448-1591) per person in 2050, although spending across countries is expected to remain varied. Interpretation Global health spending is expected to continue to grow, but remain unequally distributed between countries. We estimate that development organisations substantially increased the amount of development assistance for health provided in 2020. Continued efforts are needed to raise sufficient resources to mitigate the pandemic for the most vulnerable, and to help curtail the pandemic for all. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.
10.	Sepanlou, Sadaf G., et al. (author) The global, regional, and national burden of cirrhosis by cause in 195 countries and territories, 1990-2017 : a systematic analysis for the Global Burden of Disease Study 2017 2020 In: The Lancet Gastroenterology & Hepatology. - 2468-1253. ; 5:3, s. 245-266 Journal article (peer-reviewed)abstract Background Cirrhosis and other chronic liver diseases (collectively referred to as cirrhosis in this paper) are a major cause of morbidity and mortality globally, although the burden and underlying causes differ across locations and demographic groups. We report on results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 on the burden of cirrhosis and its trends since 1990, by cause, sex, and age, for 195 countries and territories. Methods We used data from vital registrations, vital registration samples, and verbal autopsies to estimate mortality. We modelled prevalence of total, compensated, and decompensated cirrhosis on the basis of hospital and claims data. Disability-adjusted life-years (DALYs) were calculated as the sum of years of life lost due to premature death and years lived with disability. Estimates are presented as numbers and age-standardised or age-specific rates per 100 000 population, with 95% uncertainty intervals (UIs). All estimates are presented for five causes of cirrhosis: hepatitis B, hepatitis C, alcohol-related liver disease, non-alcoholic steatohepatitis (NASH), and other causes. We compared mortality, prevalence, and DALY estimates with those expected according to the Socio-demographic Index (SDI) as a proxy for the development status of regions and countries. Findings In 2017, cirrhosis caused more than 1.32 million (95% UI 1.27-1.45) deaths (440000 [416 000-518 000; 33.3%] in females and 883 000 [838 000-967 000; 66.7%] in males) globally, compared with less than 899 000 (829 000-948 000) deaths in 1990. Deaths due to cirrhosis constituted 2.4% (2.3-2.6) of total deaths globally in 2017 compared with 1.9% (1.8-2.0) in 1990. Despite an increase in the number of deaths, the age-standardised death rate decreased from 21.0 (19.2-22.3) per 100 000 population in 1990 to 16.5 (15.8-18-1) per 100 000 population in 2017. Sub-Saharan Africa had the highest age-standardised death rate among GBD super-regions for all years of the study period (32.2 [25.8-38.6] deaths per 100 000 population in 2017), and the high-income super-region had the lowest (10.1 [9.8-10-5] deaths per 100 000 population in 2017). The age-standardised death rate decreased or remained constant from 1990 to 2017 in all GBD regions except eastern Europe and central Asia, where the age-standardised death rate increased, primarily due to increases in alcohol-related liver disease prevalence. At the national level, the age-standardised death rate of cirrhosis was lowest in Singapore in 2017 (3.7 [3.3-4.0] per 100 000 in 2017) and highest in Egypt in all years since 1990 (103.3 [64.4-133.4] per 100 000 in 2017). There were 10.6 million (10.3-10.9) prevalent cases of decompensated cirrhosis and 112 million (107-119) prevalent cases of compensated cirrhosis globally in 2017. There was a significant increase in age-standardised prevalence rate of decompensated cirrhosis between 1990 and 2017. Cirrhosis caused by NASH had a steady age-standardised death rate throughout the study period, whereas the other four causes showed declines in age-standardised death rate. The age-standardised prevalence of compensated and decompensated cirrhosis due to NASH increased more than for any other cause of cirrhosis (by 33.2% for compensated cirrhosis and 54.8% for decompensated cirrhosis) over the study period. From 1990 to 2017, the number of prevalent cases snore than doubled for compensated cirrhosis due to NASH and more than tripled for decompensated cirrhosis due to NASH. In 2017, age-standardised death and DALY rates were lower among countries and territories with higher SDI. Interpretation Cirrhosis imposes a substantial health burden on many countries and this burden has increased at the global level since 1990, partly due to population growth and ageing. Although the age-standardised death and DALY rates of cirrhosis decreased from 1990 to 2017, numbers of deaths and DALYs and the proportion of all global deaths due to cirrhosis increased. Despite the availability of effective interventions for the prevention and treatment of hepatitis B and C, they were still the main causes of cirrhosis burden worldwide, particularly in low-income countries. The impact of hepatitis B and C is expected to be attenuated and overtaken by that of NASH in the near future. Cost-effective interventions are required to continue the prevention and treatment of viral hepatitis, and to achieve early diagnosis and prevention of cirrhosis due to alcohol-related liver disease and NASH.
11.	Adcox, K, et al. (author) Construction and performance of the PHENIX pad chambers 2003 In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 497:2-3, s. 263-293 Journal article (peer-reviewed)abstract We present the Pad Chamber detector system in the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. The three station system provides space points along each track in the spectrometer arms at mid-rapidity and covers a total area of 88 m(2). Its main functions are to provide the track coordinate along the beam and to ensure reliable pattern recognition at very high particle multiplicity. A new concept for two dimensional wire chamber readout via its finely segmented cathode was developed. The full readout system, comprising 172 800 electronic channels, is described together with the challenging design of the chambers. The electronics, mounted on the outer chamber face, together with the chamber itself amounts to 1.2% of a radiation length. Results from cosmic ray tests, showing an average efficiency better than 99.5% for all chambers are presented. The experiences from the full scale operation in the first run are reported. (C) 2002 Elsevier Science B.V. All rights reserved.
12.	Caretta, Martina Angela, et al. (author) Water 2022 In: Climate Change 2022: Impacts, Adaptation and Vulnerability : Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change - Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Book chapter (other academic/artistic)
13.	Gudmundsdottir, Valborg, et al. (author) Whole blood co-expression modules associate with metabolic traits and type 2 diabetes : an IMI-DIRECT study 2020 In: Genome Medicine. - : BioMed Central. - 1756-994X. ; 12:1 Journal article (peer-reviewed)abstract Background: The rising prevalence of type 2 diabetes (T2D) poses a major global challenge. It remains unresolved to what extent transcriptomic signatures of metabolic dysregulation and T2D can be observed in easily accessible tissues such as blood. Additionally, large-scale human studies are required to further our understanding of the putative inflammatory component of insulin resistance and T2D. Here we used transcriptomics data from individuals with (n = 789) and without (n = 2127) T2D from the IMI-DIRECT cohorts to describe the co-expression structure of whole blood that mainly reflects processes and cell types of the immune system, and how it relates to metabolically relevant clinical traits and T2D.Methods: Clusters of co-expressed genes were identified in the non-diabetic IMI-DIRECT cohort and evaluated with regard to stability, as well as preservation and rewiring in the cohort of individuals with T2D. We performed functional and immune cell signature enrichment analyses, and a genome-wide association study to describe the genetic regulation of the modules. Phenotypic and trans-omics associations of the transcriptomic modules were investigated across both IMI-DIRECT cohorts.Results: We identified 55 whole blood co-expression modules, some of which clustered in larger super-modules. We identified a large number of associations between these transcriptomic modules and measures of insulin action and glucose tolerance. Some of the metabolically linked modules reflect neutrophil-lymphocyte ratio in blood while others are independent of white blood cell estimates, including a module of genes encoding neutrophil granule proteins with antibacterial properties for which the strongest associations with clinical traits and T2D status were observed. Through the integration of genetic and multi-omics data, we provide a holistic view of the regulation and molecular context of whole blood transcriptomic modules. We furthermore identified an overlap between genetic signals for T2D and co-expression modules involved in type II interferon signaling.Conclusions: Our results offer a large-scale map of whole blood transcriptomic modules in the context of metabolic disease and point to novel biological candidates for future studies related to T2D.
14.	Hakkarainen, Teppo, et al. (author) Spatially resolved characterization of InGaAs/GaAs quantum dot structures by scanning spreading resistance microscopy 2010 In: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 97:4, s. 041106- Journal article (peer-reviewed)abstract Cross-sectional scanning spreading resistance microscopy (SSRM) is used to investigate stacked InGaAs/GaAs quantum dot (QD) structures with different doping schemes. Spatially resolved imaging of the QDs by SSRM is demonstrated. The SSRM contrast obtained for the QD layers is found to depend on doping in the structure. In the undoped structures both QD-layers and QDs within the layers could be resolved, while in the doped structures the QD layers appear more or less uniformly broadened. The origin of the SSRM contrast in the QD layer in the different samples is discussed and correlated with doping schemes. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3467138]
15.	Kuznetsov, A. Y., et al. (author) Dynamic annealing in ion implanted SiC : Flux versus temperature dependence 2003 In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 94:11, s. 7112-7115 Journal article (peer-reviewed)abstract A strong influence of ion implantation flux on the accumulation of radiation damage, the so-called dose rate effect, is observed and systematically studied in SiC. 100 keV Si+ ions were implanted into bulk 4H-SiC wafers using different ion fluxes (1.9x10(10)-4.9x10(13) ions/cm(2) s) and keeping the implantation dose constant at 5x10(14) Si+/cm(2). The implants were performed both at room and elevated temperatures, up to 220 degreesC. Rutherford backscattering spectrometry in the channelling mode using 2 MeV He+ ions was employed to measure ion implantation damage profiles in the samples. For the flux interval used the most, pronounced dynamic annealing effect was detected at 80-160degreesC, having an activation energy of 1.3 eV. For example, at 100degreesC the amount of disordered Si atoms at the projected ion range is reduced by a factor of 4 by decreasing the ion flux from 4.9x10(13) to 1.9x10(10) ions/cm(2) s. The results are discussed in terms of migration and annihilation of intrinsic type defects for both the Si- and C-sublattices. In addition, two regions for the damage accumulation - at the surface and at the damage peak for 100 keV Si+ ions - are observed.
16.	Lalita, J, et al. (author) Defect evolution in MeV ion-implanted silicon 1996 In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS. - : ELSEVIER SCIENCE BV. - 0168-583X. ; 120:1-4, s. 27-32 Journal article (other academic/artistic)abstract Lightly doped silicon samples of both n- and p-type, have been implanted with low doses of H, B and Si ions using energies between 1 and 6 MeV. The resulting electrically active point defects were characterized by deep level transient spectroscopy (DLTS)
17.	Leveque, P., et al. (author) Identification of hydrogen related defects in proton implanted float-zone silicon 2003 In: European Physical Journal. - : EDP Sciences. - 1286-0042 .- 1286-0050. ; 23:1, s. 5-9 Journal article (peer-reviewed)abstract Hydrogen related defects in high purity n-type float zone silicon samples have been studied by means of Deep Level Transient Spectroscopy. They were introduced, as well as the characteristic vacancy-oxygen (VO) and divacancy (V-2) centers, by MeV proton implantation. Two hydrogen related defect levels were resolved at 0.32 eV and 0.45 eV below the conduction band edge (E-c). Careful annealing studies indicate strongly that a third hydrogen related level, overlapping with the singly negative charge state level of V-2, is also present in the implanted samples. The annealing behavior of the hydrogen related defects has been compared with literature data leading to a rather firm identification. The E-c-0.32 eV level originates from a VO center partly saturated with hydrogen (a VOH complex) while the E-c-0.45 eV level may be ascribed to a complex involving a monovacancy and a hydrogen atom ( a VH complex). The third hydrogen related defect is tentatively ascribed to a complex involving a hydrogen atom and a divacancy ( a V2H complex).
18.	Leveque, Patrick, et al. (author) Vacancy and interstitial depth profiles in ion-implanted silicon. 2003 In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 93:2, s. 871-877 Journal article (peer-reviewed)abstract An experimental method of studying shifts between concentration-versus-depth profiles of vacancy- and interstitial-type defects in ion-implanted silicon is demonstrated. The concept is based on deep level transient spectroscopy measurements utilizing the filling pulse variation technique. The vacancy profile, represented by the vacancy-oxygen center, and the interstitial profile, represented by the interstitial carbon-substitutional carbon pair, are obtained at the same sample temperature by varying the duration of the filling pulse. The effect of the capture in the Debye tail has been extensively studied and taken into account. Thus, the two profiles can be recorded with a high relative depth resolution. Using low doses, point defects have been introduced in lightly doped float zone n-type silicon by implantation with 6.8 MeV boron ions and 680 keV and 1.3 MeV protons at room temperature. The effect of the angle of ion incidence has also been investigated. For all implantation conditions the peak of the interstitial profile is displaced towards larger depths compared to that of the vacancy profile. The amplitude of this displacement increases as the width of the initial point defect distribution increases. This behavior is explained by a simple model where the preferential forward momentum of recoiling silicon atoms and the highly efficient direct recombination of primary point defects are taken into account.
19.	LI, G, et al. (author) ZN DELTA-DOPED GAAS GROWN BY METALORGANIC VAPOR-PHASE EPITAXY 1995 In: Journal of Crystal Growth. - 0022-0248 .- 1873-5002. ; 154, s. 231-239 Journal article (peer-reviewed)abstract A number of delta-doping parameters have been changed to study their effects on the hole concentration of Zn delta-doped GaAs grown by metalorganic vapour phase epitaxy using dimethylzinc (DMZn) as a doping precursor. We observed that the hole concentration is dependent on the DMZn partial pressure but independent of the gas now velocity in the reactor. A weak effect of the delta-doping time on the hole concentration infers that the near-equilibrium between the Zn adsorption and desorption can be reached very rapidly. In the regime of the delta-doping temperatures from 600 to 700 degrees C, the Zn desorption predominantly determines the hole concentration, and the Zn desorption activation energy obtained from the Arrhenius-type plot is 2.04 eV. Below 600 degrees C, however, the hole concentration departures from the Arrhenius-type relationship with the reciprocal delta-doping temperature, indicating that some other factors start to influence the Zn delta-doping concentration.
20.	Linnarsson, Margareta K., et al. (author) Solubility limits of dopants in 4H-SiC 2003 In: Applied Surface Science. - 0169-4332 .- 1873-5584. ; 203, s. 427-432 Journal article (peer-reviewed)abstract Epitaxial 4H-SiC structures with heavily boron or aluminium doped layers have been prepared by vapour phase epitaxy. The samples have been annealed in Ar atmosphere in an RF-heated furnace between 1700 and 2000 degreesC for 45 min to 64 h. Secondary ion mass spectrometry has been employed to obtain depth distributions as well as lateral distributions (ion imaging) for boron and aluminium. Transmission electron microscopy has been used to study the crystallinity and determine phase composition. Solubility limits of similar to 1 x 10(20) Al/cm(3) (1700 degreesC) and < 1 x 10(20) B/cm(3) (1900 degreesC) have been deduced.
21.	Lourdudoss, Sebastian, 1953-, et al. (author) Preface 2018 In: Semiconductors and Semimetals. - : Academic Press Inc.. - 9780128150993 ; , s. ix-xi Book chapter (peer-reviewed)
22.	Mahajan, Shauna L., et al. (author) Introducing Elinor for monitoring the governance and management of area-based conservation 2024 In: Conservation Biology. - 0888-8892 .- 1523-1739. ; 38:2 Journal article (peer-reviewed)abstract Monitoring the governance and management effectiveness of area-based conservation has long been recognized as an important foundation for achieving national and global biodiversity goals and enabling adaptive management. However, there are still many barriers that prevent conservation actors, including those affected by governance and management systems from implementing conservation activities and programs and from gathering and using data on governance and management to inform decision-making across spatial scales and through time. We explored current and past efforts to assess governance and management effectiveness and barriers actors face in using the resulting data and insights to inform conservation decision-making. To help overcome these barriers, we developed Elinor, a free and open-source monitoring tool that builds on the work of Nobel Prize winner Elinor Ostrom to facilitate the gathering, storing, sharing, analyzing, and use of data on environmental governance and management across spatial scales and for areas under different governance and management types. We consider the process of codesigning and piloting Elinor with conservation scientists and practitioners and the main components of the assessment and online data system. We also consider how Elinor complements existing approaches by addressing governance and management in a single assessment at a high level for different types of area-based conservation, providing flexible options for data collection, and integrating a data system with an assessment that can support data use and sharing across different spatial scales, including global monitoring of the Global Biodiversity Framework. Although challenges will continue, the process of developing Elinor and the tool itself offer tangible solutions to barriers that prevent the systematic collection and use of governance and management data. With broader uptake, Elinor can play a valuable role in enabling more effective, inclusive, and durable area-based conservation.
23.	Marcinkevicius, Saulius, et al. (author) Influence of annealing on carrier dynamics in As ion-implanted epitaxially lifted-off GaAs layers 2000 In: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 76:10, s. 1306-1308 Journal article (peer-reviewed)abstract Electrical and dynamical optical characterization of As-ion implanted and annealed GaAs has been performed. Changes of physical properties induced by annealing have been studied in detail by using layers annealed in small steps in the temperature range 500-700 degrees C. The carrier trapping rate increases exponentially with increase of inverse annealing temperature indicating that in ion-implanted GaAs ultrafast carrier capture occurs to the same trapping centers as in low-temperature-grown GaAs. Relatively large resistivity and electron mobility in As-implanted GaAs have been observed after annealing, which shows that this material possesses properties required for a variety of ultrafast optoelectronic applications.
24.	Marcinkevicius, Saulius, et al. (author) Ultrafast carrier dynamics in highly resistive InP and InGaAs produced by ion implantation 2004 In: ULTRAFAST PHENOMENA IN SEMICONDUCTORS AND NANOSTRUCTURE MATERIALS VIII. - BELLINGHAM : SPIE-INT SOC OPTICAL ENGINEERING. - 0819452602 ; , s. 299-309 Conference paper (peer-reviewed)abstract Heavy ion implantation into InP and In0.53Ga0.47As and rapid thermal annealing has been applied to produce materials with high resistivity, good mobility and ultrashort carrier lifetime, as required for ultrafast optoelectronic applications. Two implantation methods have been analyzed: Fe+ implantation into semi-insulating InP and InGaAs, and P+ implantation into p-doped InP and InGaAs. Both approaches allow production of layers with high sheet resistance, up to 10(6) Omega/square for the P+-implanted compounds. Electron mobility in the high resistivity layers is of the order of 10(2) cm(2)V(-1)s(-1). Carrier lifetimes, measured by the time-resolved photoluminescence and reflectivity, can be tuned from similar to100 femtoseconds to tens of picoseconds by choosing implantation and annealing conditions. Measurements of carrier dynamics have shown that carrier traps act as efficient recombination centers, at least for the case of InP. The dependencies of electrical and ultrafast optical properties on the implantation dose and annealing temperature are determined by the interplay between shallow P and As antisite-related donors, deep Fe-related acceptors and defect complexes.
25.	Ohlsson, Claes, 1965, et al. (author) Genetic determinants of serum testosterone concentrations in men. 2011 In: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 7:10 Journal article (peer-reviewed)abstract Testosterone concentrations in men are associated with cardiovascular morbidity, osteoporosis, and mortality and are affected by age, smoking, and obesity. Because of serum testosterone's high heritability, we performed a meta-analysis of genome-wide association data in 8,938 men from seven cohorts and followed up the genome-wide significant findings in one in silico (n=871) and two de novo replication cohorts (n=4,620) to identify genetic loci significantly associated with serum testosterone concentration in men. All these loci were also associated with low serum testosterone concentration defined as <300 ng/dl. Two single-nucleotide polymorphisms at the sex hormone-binding globulin (SHBG) locus (17p13-p12) were identified as independently associated with serum testosterone concentration (rs12150660, p=1.2×10(-41) and rs6258, p=2.3×10(-22)). Subjects with ≥ 3 risk alleles of these variants had 6.5-fold higher risk of having low serum testosterone than subjects with no risk allele. The rs5934505 polymorphism near FAM9B on the X chromosome was also associated with testosterone concentrations (p=5.6×10(-16)). The rs6258 polymorphism in exon 4 of SHBG affected SHBG's affinity for binding testosterone and the measured free testosterone fraction (p<0.01). Genetic variants in the SHBG locus and on the X chromosome are associated with a substantial variation in testosterone concentrations and increased risk of low testosterone. rs6258 is the first reported SHBG polymorphism, which affects testosterone binding to SHBG and the free testosterone fraction and could therefore influence the calculation of free testosterone using law-of-mass-action equation.
26.	Pellegrino, P., et al. (author) Annealing kinetics of vacancy-related defects in low-dose MeV self-ion-implanted n-type silicon 2001 In: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 64:19 Journal article (peer-reviewed)abstract Silicon samples of n-type have been implanted at room temperature with 5.6-MeV Si-28 ions to a dose of 2 x 10(8) cm(-2) and then annealed at temperatures from 100 to 380 degreesC. Both isothermal and isochronal treatments were performed and the annealing kinetics of the prominent divacancy (V-2) and vacancy-oxygen (VO) centers were studied in detail using deep-level transient spectroscopy. The decrease Of V2 centers exhibits first-order kinetics in both Czochralski-grown (CZ) and float-zone (FZ) samples, and the data provide strong evidence for a process involving migration of V-2 and subsequent annihilation at trapping centers. The migration energy extracted for V-2 is similar to1.3 eV and from the shape of the concentration versus depth profiles, an effective diffusion length less than or equal to0.1 mum is obtained. The VO center displays a more complex annealing behavior where interaction with mobile hydrogen (H) plays a key role through the formation of VOH and VOH2 centers. Another contribution is migration of VO and trapping by interstitial oxygen atoms in the silicon lattice, giving rise to vacancy-dioxygen pairs. An activation energy of similar to 1.8 eV is deduced for the migration of VO, in close resemblance with results from previous studies using electron-irradiated samples. A model for the annealing of VO, involving only three reactions, is put forward and shown to yield a close quantitative agreement with the experimental data for both CZ and FZ samples over the whole temperature range studied.
27.	Pellegrino, P., et al. (author) Separation of vacancy and interstitial depth profiles in proton- and boron-implanted silicon 2002 In: Nuclear Instruments and Methods in Physics Research Section B. - 0168-583X .- 1872-9584. ; 186, s. 334-338 Journal article (peer-reviewed)abstract A new experimental method of studying shifts between concentration-versus-depth profiles of vacancy-type and interstitial-type defects in ion-implanted silicon is demonstrated. The concept is based on deep level transient spectroscopy (DLTS) measurements utilizing the filling pulse variation technique. The vacancy profile. represented by the vacancy-oxygen center and the interstitial profile, represented by the substitutional carbon-interstitial carbon pair, are obtained at the same sample temperature by varying the duration of the filling pulse, Thus the two profiles can be recorded with a high relative depth resolution, Point defects have been introduced in low doped float zone n-type silicon by implantation with 6 MeV boron ions and 1.3 MeV protons at room temperature, using low doses. For each implantation condition the peak of the interstitial profile is shown to be displaced by similar to 0.5 mum towards larger depths compared to that of the vacancy profile. This shift is primarily attributed to the preferential forward momentum of recoiling Si atoms, in accordance with theoretical predictions.
28.	Siegert, Jörg, et al. (author) Recombination properties of Si-doped InGaAs/GaAs quantum dots 2006 In: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 17:21, s. 5373-5377 Journal article (peer-reviewed)abstract The recombination properties of directly doped InGaAs/GaAs quantum dots (QDs) for application in quantum dot infrared photodetectors (QDIPs) have been investigated by time-resolved photoluminescence. Compared with undoped and barrier-doped samples, the overall effect of direct dot doping is found to be small, resulting in only slight deterioration of dot homogeneity. Low-temperature photoluminescence decay times decrease very little, indicating that direct doping does not cause a significant increase of nonradiative recombination. In addition, directly doped quantum dots show a significantly weaker quenching of the photoluminescence intensity with temperature. At the same time, barrier doping causes the formation of more and smaller dots, which results in high photoluminescence intensity at low temperatures but an early onset of thermal carrier emission from the dots. The results suggest that direct QD doping is more prospective for realizing room-temperature operation in QDIPs.
29.	Slotte, J., et al. (author) Fluence, flux, and implantation temperature dependence of ion-implantation-induced defect production in 4H-SiC 2005 In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 97:3 Journal article (peer-reviewed)abstract Vacancy-type defect production in Al- and Si-implanted 4H-SiC has been studied as a function of ion fluence, ion flux, and implantation temperature in the projected ion range region by positron annihilation spectroscopy and Rutherford backscattering techniques. Ion channeling measurements show that the concentration of displaced silicon atoms increases rapidly with increasing ion fluence. In the ion fluence interval of 10(13)-10(14) cm(-2) the positron annihilation parameters are roughly constant at a defect level tentatively associated with the divacancy VCVSi. Above the ion fluence of 10(14) cm(-2) larger vacancy clusters are formed. For implantations as a function of ion flux (cm(-2) s(-1)), ion channeling and positron annihilation measurements behave similarly, i.e., indicating increasing damage in the projected range region with increasing ion flux. However, for samples implanted at different temperatures the positron annihilation parameter S shows a clear minimum at approximately 100 degreesC, whereas the normalized backscattering yield decrease continuously with increasing implantation temperature. This is explained by the formation of larger vacancy clusters when the implantation temperature is increased.
30.	Svensson, BG, et al. (author) Doping of silicon carbide by ion implantation 2001 In: Materials Science Forum, Vols. 353-356. - : Trans Tech Publications Inc.. - 9780878498734 - 0878498737 ; , s. 549-554, s. 549-554 Conference paper (peer-reviewed)abstract A brief survey is given of some recent results on doping of 4H- and 6H-SiC by ion implantation. The doses and energies used are between 10(9) and 10(15) cm(-2) and 100 keV and 5 MeV, respectively, and B and Al ions (p-type dopants) are predominantly studied. After low dose implantation (less than or equal to 10(10) cm(-2)) a strong compensation is observed in n-type samples and this holds irrespective of implantation temperature up to 600 degreesC. However, at higher doses (10(14)-10(15) Al/cm(2)) the rate of defect recombination (annihilation) increases substantially during hot implants (greater than or equal to 200 degreesC) and in these samples one type of structural defect dominates after past-implant annealing at 1700-2000 degreesC. The defect is identified as a dislocation loop composed of clustered interstitial atoms inserted on the basal plane in the hexagonal crystal structure. Finally, transient enhanced diffusion (TED) of ion-implanted boron in 4H-samples is discussed.
31.	Svensson, B.G., et al. (author) Ion implantation processing and related effects in SiC 2006 In: Silicon Carbide and Related Materials 2005, Pts 1 and 2. - 9780878494255 ; , s. 781-786 Conference paper (peer-reviewed)abstract A brief survey is given of some recent progress regarding ion implantation processing and related effects in 4H- and 6H-SiC. Four topics are discussed; an empirical ion range distribution simulator, dynamic defect annealing during implantation, formation of highly p(+)-doped layers, and deactivation of N donors by ion-induced defects.
32.	Svensson, BG, et al. (author) Generation of vacancy-type point defects in single collision cascades during swift-ion bombardment of silicon 1997 In: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMER INST PHYSICS. - 0163-1829. ; 55:16, s. 10498-10507 Journal article (other academic/artistic)abstract Silicon samples of n-type have been implanted with low doses (10(7)-10(10) cm(-2)) of B-11, C-12, O-16, Si-28, Ge-74,Ge-76, and Sn-120 ions using energies between 0.4 and 8.0 MeV. Because of the low doses employed, single-collision cascades prevail, and a
33.	Svensson, BG, et al. (author) Point defects in MeV ion-implanted silicon studied by deep level transient spectroscopy 1995 In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS. ; 106:1-4 Other publication (other academic/artistic)
34.	Wong-Leung, J., et al. (author) Ion implantation in 4H-SiC 2008 In: Nuclear Instruments and Methods in Physics Research Section B. - : Elsevier BV. - 0168-583X .- 1872-9584. ; 266:8, s. 1367-1372 Journal article (peer-reviewed)abstract Silicon carbide offers unique applications as a wide bandgap semiconductor. This paper reviews various aspects of ion implantation in 4H-SiC studied with a view to optimise ion implantation in silicon carbide. Al, P and Si ions with keV energies were used. Channelling effects were studied in both a-axis and c-axis crystals as a function of tilts along major orthogonal planes and off the major orthogonal planes. Major axes such as [0 0 0 1] and the [ 1 1 (2) over bar 0] and minor axis like the [1 1 (2) over bar 3] showed long channelling tails and optimum tilts for minimising channelling are recommended. TEM analyses of the samples showed the formation of (0 0 0 1) prismatic loops and the (1 1 (2) over bar 0) loops as well,in both a and c-cut crystals. We also note the presence of voids only in P implanted samples implanted with amorphising doses. The competing process between damage accumulation and dynamic annealing was studied by determining the critical temperature for the transition between crystalline and amorphous SiC and an activation energy of 1.3 eV is extracted.

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