| 1. |
- Ademuyiwa, Adesoji O., et al.
(författare)
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Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
- 2016
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Ingår i: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
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| 2. |
- Borg, Erik, et al.
(författare)
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Behavioural awareness, interaction and counselling education in audiological rehabilitation : development of methods and application in a pilot study
- 2002
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Ingår i: International Journal of Audiology. - 1499-2027 .- 1708-8186. ; 41:5, s. 308-320
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Tidskriftsartikel (refereegranskat)abstract
- In conventional audiological rehabilitation, the hearing therapist interacts with the hearing-impaired person and with significant others. In order to strengthen the personality and self-confidence of the hearing-impaired individual, a different strategy was designed and implemented whereby the pedagogic interaction was directed only towards the hearing-impaired individual, who in turn worked as a tutor/aid/counsellor to the communication partner. On the basis of an interactive communication model, new methods for rehabilitation of subjects with moderate hearing impairment were developed and evaluated in a pilot study on 13 men with noise-induced hearing loss. A course programme was developed with three main active components: (1) increased insight and knowledge; (2) education as counsellors with the ability to focus on the problems of the communication partner; and (3) motivation to change through group discussion and reflexive conversation. Increased insight and knowledge were obtained through test and training experiences in a sound environmental chamber, tutorials and discussions. The pedagogic training focused on helping the hearing-impaired subjects to become able communication counsellors in relation to their interlocutors. An act-react, offensive-defensive paradigm was used in conjunction with transactional analysis. Results of the pilot study were evaluated using questionnaires, interviews and a method of dialogue analysis. The results were evaluated for the hearing-impaired and the partner and in recordings of conversations in the home environment. There were clearly positive cognitive and emotional effects seen in the inquiries and interviews. The observations from the dialogue analysis indicated only small effects, with the exception of the two individuals with the most pronounced functional impairment, for whom dialogue was improved after the course. It was concluded that these new methods could contribute new possibilities in rehabilitation programmes, emphasizing the shared responsibility for communication and the unique competence and abilities of the hearing-impaired person.
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| 3. |
- Borg, Erik, et al.
(författare)
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New perspectives on counselling in audiological habilitation/rehabilitation
- 2015
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Ingår i: International Journal of Audiology. - : Informa Healthcare. - 1499-2027 .- 1708-8186. ; 54:1, s. 11-19
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To develop and apply a pedagogical method focusing on Empowerment, Empathy, Competence, and Counselling: the EC programme, and to present an initial evaluation. Design: The EC programme was gradually developed within a study circle framework and in dialogue with study circle leaders and participants (clients) with hearing impairment (HI). An evaluation was carried out with the study circle leaders. Study sample : Seventeen upper secondary school students with HI took part in the development of the programme. Eighteen study circle leaders responded to a questionnaire. Results: The EC programme developed consisted of films, CD, and DVD productions to increase insight into one's own hearing ability, to demonstrate for others what HI means, strategies to evaluate situations, and help to act constructively in social situations. The study circle leaders found most of the course material appropriate and easy to use, as a whole or in parts. The leaders' evaluations indicated that the clients had increased their knowledge about how the HI affected themselves and others. The clients had improved their self-confidence and their empathic view of others. Conclusion: The EC programme can be used in its entirety or in part. Participation may lead to increased empowerment, empathy, competence and counselling ability.
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| 4. |
- Borg, Mattias, et al.
(författare)
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InAs/GaSb Heterostructure Nanowires for Tunnel Field-Effect Transistors.
- 2010
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Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 10:Online August 24, 2010, s. 4080-4085
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Tidskriftsartikel (refereegranskat)abstract
- InAs/GaSb nanowire heterostructures with thin GaInAs inserts were grown by MOVPE and characterized by electrical measurements and transmission electron microscopy. Down-scaling of the insert thickness was limited because of an observed sensitivity of GaSb nanowire growth to the presence of In. By employing growth interrupts in between the InAs and GaInAs growth steps it was possible to reach an insert thickness down to 25 nm. Two-terminal devices show a diode behavior, where temperature-dependent measurements indicate a heterostructure barrier height of 0.5 eV, which is identified as the valence band offset between the InAs and GaSb. Three-terminal transistor structures with a top-gate positioned at the heterointerface show clear indications of band-to-band tunnelling.
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| 5. |
- Bång, Joakim
(författare)
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Purification, Stereoisomeric Analysis and Quantification of Biologically Active Compounds in Extracts from Pine Sawflies, African Butterflies and Orchid Bees
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Stereochemistry plays an important role in nature because biologically important molecules such as amino acids, nucleotides and sugars, only exist in enantiomerically pure forms. Semiochemicals carry messages, between the same species (pheromones) and between different species (allelochemicals). Both pheromones and allelochemicals can be used as environmentally friendly pest management. Many semiochemicals, i.e. behaviour modifying chemicals, consist of pure or well-defined mixtures of stereoisomers, where some of the other stereoisomers can be repellent. It is therefore important to be able to separate them to produce a synthetic pheromone in a mixture that is attractive.Pine sawflies are a family of insects that in some cases can be severe defoliators of conifer trees. Diprion pini, Diprion similis and Neodiprion sertifer are severe pests for these trees and have got the most attention in pine sawfly pheromone studies. The pheromone precursors are stored in the female body as long-chain secondary alcohols, which, when released, are esterified to acetates or propionates. The alcohols are chiral, and normally one of the stereoisomer is the main pheromone component, sometimes possible together with other stereoisomers as essential minor components.Bicyclus is a genus of African butterflies, and especially Bicyclus anynana has become a popular model for the study of life history evolution, morphology, mating choice and genetics. The wing pattern of Bicyclus differs depending on the season, with large eyespots during the rain-season and small or absent spots during the dry season. Euglossa is one of the genera among the orchid bees in the Neotropics that does not produce its own pheromone. Instead, the males collect fragrances from orchids and other sources and store them in a pocket in their hind legs. Both Bicyclus and Euglossa use semiochemicals similar to pine sawflies, and thus can be analysed by the same methods.Pheromones and other semiochemicals in insects are often present in low amounts in a complex matrix, and purification of the sample before chemical analysis is often required. A common method is gradient elution on a solid phase silica column. Separation of stereoisomers can be achieved either by using a column with a chiral stationary phase (CSP) or with pre-column derivatisation using a column with an achiral stationary phase (ASP) or a combination of both, with mass detection as the dominant detection method. The purpose of this work has been to improve the purification method, find suitable methods to separate the stereoisomers of secondary alcohols, and to apply this on extracts of insects.By selecting the right fractions to collect during gradient elution the purification method was optimised. To reduce plasticizer contamination from ordinary columns, solid phase columns of Teflon or glass were used. For pre-column derivatisation of different chiral alcohols various acid chlorides were tested. For the pine sawfly pheromone precursors enantiopure (2S)-2-acetoxypropionyl chloride was the best choice. To separate some of the stereoisomers achiral 2-naphthoyl chloride was used. For derivatisation of 6,10,14-trimethylpentadecan-2-ol (R)-trans-chrysanthemoyl chloride was the best choice. The derivatised alcohols were separated on different columns, both chiral and non-chiral. Varian FactorFour VF-23ms was chosen as a general-purpose column, the Agilent HP-88 column was the best column with an ASP of those tested, and the Chiraldex B-PA column (CSP) was the only one that could separate all eight stereoisomers of derivatised 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, and 3,7-dimethyltridecan-2-ol.To determine the stereoisomeric purity of standard solutions used in field experiments and extracts of different species of insects the optimised methods were applied. For extracts from B. anynana, Euglossa and Neodiprion lecontei this work describe the first determination of the stereochemistry of some of their semiochemicals.For the determination of the stereochemistry of chiral semiochemicals the methods for purification and separation presented herein have shown to be of great value. The results will hopefully contribute to a better understanding of the communication among insects, and ultimately to a more environmentally friendly pest control.
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| 6. |
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| 7. |
- Carlsson, Per-Inge, et al.
(författare)
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The influence of genetic variation in oxidative stress genes on human noise susceptibility
- 2005
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Ingår i: Hearing Research. - 0378-5955 .- 1878-5891. ; 202:1-2, s. 87-96
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Tidskriftsartikel (refereegranskat)abstract
- Noise induced hearing loss (NIHL) is a complex disease caused by an interaction between genetic and environmental factors. Damage in the cochlea as a result of noise exposure appears to be mediated by reactive oxygen species (ROS). To investigate whether genetic variation in the human protective antioxidant system is associated with high or low susceptibility to NIHL, genetic polymorphisms derived from genes involved in the oxidative stress response were analysed in the 10% most susceptible and 10% most resistant extremes of 1200 Swedish noise-exposed workers. The genetic polymorphisms included 2 deletion polymorphisms for the GSTM1 and GSTT1 gene, and 14 SNPs derived from the CAT, SOD, GPX, GSR and GSTP1 genes. No significant differences were found between susceptible and resistant groups, providing no support for a major role of genetic variation of antioxidant enzymes in the susceptibility to NIHL.
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| 8. |
- Dey, Anil, et al.
(författare)
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15 nm diameter InAs nanowire MOSFETs
- 2011
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Ingår i: [Host publication title missing]. - 1548-3770. ; , s. 21-22
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Konferensbidrag (refereegranskat)abstract
- InAs is an attractive channel material for III–V nanowire MOSFETs and early prototype high performance nanowire transistors have been demonstrated1. As the gate length is reduced, the nanowire diameter must be scaled quite aggressively in order to suppress short-channel effects2. However, a reduction in transconductance (gm) and drive current (ION) could be expected due to increased surface scattering for thin wires. We present data for the device properties of thin InAs nanowires, with diameters in the 15 nm range, and investigate possible improvements of the performance focusing on transistor applications. In order to boost ION, the source and drain resistance need to be reduced. Several doping sources were therefore evaluated in the study, among them selenium (Se), tin (Sn) and sulphur (S) to form n-i-n structures. We report very high current densities, up to 33 MA/cm2, comparable to modern HEMTs3, and a normalized transconductance of 1.8 S/mm for a nanowire with an intrinsic segment of nominally 150 nm and a diameter of 15 nm.
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| 9. |
- Dey, Anil, et al.
(författare)
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GaSb nanowire pFETs for III-V CMOS
- 2013
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Ingår i: IEEE Device Research Conference. Proceedings. - 1548-3770. ; , s. 13-14
-
Konferensbidrag (refereegranskat)
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| 10. |
- Dey, Anil, et al.
(författare)
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High Current Density InAsSb/GaSb Tunnel Field Effect Transistors
- 2012
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Ingår i: Device research conference. - 1548-3770. ; , s. 205-206
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Konferensbidrag (refereegranskat)abstract
- Steep-slope devices, such as tunnel field-effect transistors (TFETs), have recently gained interest due to their potential for low power operation at room temperature. The devices are based on inter-band tunneling which could limit the on-current since the charge carriers must tunnel through a barrier to traverse the device. The InAs/GaSb heterostructure forms a broken type II band alignment which enables inter-band tunneling without a barrier, allowing high on-currents. We have recently demonstrated high current density (Ion,reverse = 17.5 mA/µm) nanowire Esaki diodes and in this work we investigate the potential of InAs/GaSb heterostructure nanowires to operate as TFETs. We present device characterization of InAs 0.85 Sb 0.15 /GaSb nanowire TFETs, which exhibit record-high on-current levels.
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| 11. |
- Dey, Anil, et al.
(författare)
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High-Current GaSb/InAs(Sb) Nanowire Tunnel Field-Effect Transistors
- 2013
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Ingår i: IEEE Electron Device Letters. - 0741-3106. ; 34:2, s. 211-213
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Tidskriftsartikel (refereegranskat)abstract
- We present electrical characterization of GaSb/InAs(Sb) nanowire tunnel field-effect transistors. The broken band alignment of the GaSb/InAs(Sb) heterostructure is exploited to allow for interband tunneling without a barrier, leading to high ON-current levels. We report a maximum drive current of 310 μA/μm at Vds = 0.5 V. Devices with scaled gate oxides display transconductances up to gm = 250 mS/mm at Vds = 300 mV, which are normalized to the nanowire circumference at the axial heterojunction.
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| 12. |
- Dey, Anil, et al.
(författare)
-
High-performance 15 nm diameter InAs nanowire Ω-gate MOSFETs
- 2012
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Konferensbidrag (refereegranskat)abstract
- In this paper we present 15 nm InAs nanowire lateral MOSFETs with an Ω-gate. The nanowires are grown from size-selected Au-aerosols by means of metal-organic vapor phase epixtaxy (MOVPE). In order to reduce the source and drain resistances, n-type dopants were introduced in the bottom and top parts of the nanowire forming a n-i-n structure. We report experimental data for 15 nm InAs nanowire MOSFETs, LG = 150 nm, with a normalized transconducatance gm = 0.7 S/mm (normalized to the circumference) and a current density Je = 24 MA/cm, comparable to modern high electron mobility transistors (HEMTs)
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| 13. |
- Dey, Anil, et al.
(författare)
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High-Performance InAs Nanowire MOSFETs
- 2012
-
Ingår i: IEEE Electron Device Letters. - 0741-3106. ; 33:6, s. 791-793
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Tidskriftsartikel (refereegranskat)abstract
- In this letter, we present a 15-nm-diameter InAs nanowire MOSFET with excellent on and off characteristics. An n-i-n doping profile was used to reduce the source and drain resistances, and an Al2O3/HfO2 bilayer was introduced in the high-k process. The nanowires exhibit high drive currents, up to 1.25 A/mm, normalized to the nanowire circumference, and current densities up to 34 MA/cm2 (VD = 0.5 V). For a nominal LG = 100 nm, we observe an extrinsic transconductance (gm) of 1.23 S/mm and a subthreshold swing of 93 mV/decade at VD = 10 mV.
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| 14. |
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| 15. |
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| 16. |
- Egard, Mikael, et al.
(författare)
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60 GHz Wavelet Generator for Impulse Radio Applications
- 2009
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Ingår i: European Microwave Conference, 2009. EuMC 2009. - 9781424447480 ; , s. 1908-1911, s. 234-237
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Konferensbidrag (refereegranskat)abstract
- A wavelet generator producing 100 ps short pulses at 60 GHz is presented. The wavelet generator consists of a gated tunnel diode (GTD) integrated in parallel with an inductor. This forms a negative differential conductance (NDC) oscillator with the ability to switch the NDC property on and off, which makes it possible to generate short pulses. In the experiments described, the wavelet generator drives a 50 Omega load and delivers 206 mV(pp) when generating 97 ps short pulses at 60 GHz. It Is demonstrated that it is possible to generate pulses of different length and phase. An explanation of the almost instantaneously startup and decay lapse of the oscillator, including generation of signals with opposite phase, is presented. This novel circuit may find use in ultra-wideband impulse radio communication.
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| 17. |
- Egard, Mikael, et al.
(författare)
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Frequency Modulation in mm-Wave InGaAs MOSFET/RTD Wavelet Generators
- 2013
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Ingår i: 2013 International Conference on Indium Phosphide and Related Materials (IPRM). - 1092-8669. ; , s. 1-2
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Konferensbidrag (refereegranskat)abstract
- Co-integration of an InGaAs MOSFET and an RTD is performed to realize a wavelet generator. The large transconductance of the MOSFET (1.9 mS/mu m) is used to switch the current in an oscillator circuit and coherent wavelets down to 41 ps are generated in the frequency domain of 50 to 100 GHz. The lowest power consumption measured is 1.9 pJ/pulse. It is found that the supply bias can be used to modulate the center frequency of the wavelets.
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| 18. |
- Egard, Mikael, et al.
(författare)
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High-Frequency Performance of Self-Aligned Gate-Last Surface Channel In0.53Ga0.47As MOSFET
- 2012
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Ingår i: IEEE Electron Device Letters. - 0741-3106. ; 33:3, s. 369-371
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Tidskriftsartikel (refereegranskat)abstract
- We have developed a self-aligned L-g = 55 nm In-0.53 Ga-0.47 As MOSFET incorporating metal-organic chemical vapor deposition regrown n(++) In0.6Ga0.4As source and drain regions, which enables a record low on-resistance of 199 Omega mu m. The regrowth process includes an InP support layer, which is later removed selectively to the n(++) contact layer. This process forms a high-frequency compatible device using a low-complexity fabrication scheme. We report on high-frequency measurements showing f(max) of 292 GHz and f(t) of 244 GHz. These results are accompanied by modeling of the device, which accounts for the frequency response of gate oxide border traps and impact ionization phenomenon found in narrow band gap FETs. The device also shows a high drive current of 2.0 mA/mu m and a high extrinsic transconductance of 1.9 mS/mu m. These excellent properties are attributed to the use of a gate-last process, which does not include high temperature or dry-etch processes.
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| 19. |
- Egard, Mikael, et al.
(författare)
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High Transconductance Self-Aligned Gate-Last Surface Channel In0.53Ga0.47As MOSFET
- 2011
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Ingår i: 2011 IEEE International Electron Devices Meeting (IEDM). - 9781457705052
-
Konferensbidrag (refereegranskat)abstract
- In this paper we present a 55 nm gate length In0.53Ga0.47As MOSFET with extrinsic transconductance of 1.9 mS/mu m and on-resistance of 199 Omega mu m. T he self-aligned MOSFET is formed using metalorganic chemical vapor deposition regrowth of highly doped source and drain access regions. The fabricated 140 nm gate length devices shows a low subthreshold swing of 79 mV/decade, which is attributed to the described low temperature gate-last process scheme.
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| 20. |
- Egard, Mikael, et al.
(författare)
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In0.53Ga0.47As RTD-MOSFET Millimeter-Wave Wavelet Generator
- 2012
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Ingår i: IEEE Electron Device Letters. - 0741-3106. ; 33:7, s. 970-972
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Tidskriftsartikel (refereegranskat)abstract
- We report on the fabrication of a self-aligned regrown In0.53Ga0.47As metal-oxide-semiconductor field-effect transistor (MOSFET) and a resonant tunneling diode (RTD). The performance of these devices is demonstrated by integrating them in parallel with an inductive coplanar waveguide stub to form a highly energy-efficient 70-GHz wavelet generator. The fast switching and low on-resistance of the MOSFET make it possible to kick-start and rapidly quench this RTD-driven oscillator circuit, which produces 41-ps-short wavelets at 15 Gpulses/s, a peak output power of 7 dBm, and an energy consumption of 1.9 pJ/pulse.
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| 21. |
- Egard, Mikael, et al.
(författare)
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Self-aligned gate-last surface channel In0.53Ga0.47As MOSFET with selectively regrown source and drain contact layers
- 2011
-
Ingår i: 69th Device Research Conference, DRC 2011 - Conference Digest. - 9781612842417
-
Konferensbidrag (refereegranskat)abstract
- III-V MOSFETs are currently being considered as a candidate for future high performance transistors [1]. In particular, In1-xGaxAs compounds are investigated for application in digital logic due to their advantageous electronic properties [2]. III-V technologies may be introduced beyond the 22 nm node, which will require a self aligned III/V device architecture as well as integration of high-¿ gate oxides.
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| 22. |
- Egard, Mikael, et al.
(författare)
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Vertical InAs nanowire wrap gate transistors with f(t) > 7 GHz and f(max) > 20 GHz.
- 2010
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 10:3, s. 809-812
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Tidskriftsartikel (refereegranskat)abstract
- In this letter we report on high-frequency measurements on vertically standing III-V nanowire wrap-gate MOSFETs (metal-oxide-semiconductor field-effect transistors). The nanowire transistors are fabricated from InAs nanowires that are epitaxially grown on a semi-insulating InP substrate. All three terminals of the MOSFETs are defined by wrap around contacts. This makes it possible to perform high-frequency measurements on the vertical InAs MOSFETs. We present S-parameter measurements performed on a matrix consisting of 70 InAs nanowire MOSFETs, which have a gate length of about 100 nm. The highest unity current gain cutoff frequency, f(t), extracted from these measurements is 7.4 GHz and the maximum frequency of oscillation, f(max), is higher than 20 GHz. This demonstrates that this is a viable technique for fabricating high-frequency integrated circuits consisting of vertical nanowires.
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| 23. |
- Ganjipour, Bahram, et al.
(författare)
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Carrier control and transport modulation in GaSb/InAsSb core/shell nanowires
- 2012
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 101:10
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Tidskriftsartikel (refereegranskat)abstract
- We report transport studies of GaSb/InAs core/shell nanowires. It is shown that with increasing InAs shell thickness, it is possible to tune the carrier concentrations and transport in the structures from p-type (core-dominated) to n-type (shell dominated). For nanowires with an intermediate shell thickness (5-7 nm), we show that the transport is ambipolar, such that an applied top-gate potential can provide further control of carrier type and transport path. In this range, the nature of the GaSb-InAs junction also changes from broken gap (semimetal) to staggered (narrow bandgap) with a small decrease in shell thickness. From a device point of view, we demonstrate that the presence of a thin (<3 nm) InAs shell improves p-type GaSb nanowire transistor characteristics. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4749283]
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| 24. |
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| 25. |
- Ganjipour, Bahram, et al.
(författare)
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High current density Esaki tunnel diodes based on GaSb-InAsSb heterostructure nanowires
- 2011
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 11:10, s. 4222-4226
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Tidskriftsartikel (refereegranskat)abstract
- We present electrical characterization of broken gap GaSb-InAsSb nanowire heterojunctions. Esaki diode characteristics with maximum reverse current of 1750 kA/cm2 at 0.50 V, maximum peak current of 67 kA/cm2 at 0.11 V, and peak-to-valley ratio (PVR) of 2.1 are obtained at room temperature. The reverse current density is comparable to that of state-of-the-art tunnel diodes based on heavily doped p-n junctions. However, the GaSb-InAsSb diodes investigated in this work do not rely on heavy doping, which permits studies of transport mechanisms in simple transistor structures processed with high-κ gate dielectrics and top-gates. Such processing results in devices with improved PVR (3.5) and stability of the electrical properties.
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| 26. |
- Gorji, Sepideh, et al.
(författare)
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Uniform and position-controlled InAs nanowires on 2('') Si substrates for transistor applications.
- 2012
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Ingår i: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 23:1
-
Tidskriftsartikel (refereegranskat)abstract
- This study presents a novel approach for indirect integration of InAs nanowires on 2('') Si substrates. We have investigated and developed epitaxial growth of InAs nanowires on 2('') Si substrates via the introduction of a thin yet high-quality InAs epitaxial layer grown by metalorganic vapor phase epitaxy. We demonstrate well-aligned nanowire growth including precise position and diameter control across the full wafer using very thin epitaxial layers (<300 nm). Statistical analysis results performed on the grown nanowires across the 2('') wafer size verifies our full control on the grown nanowire with 100% growth yield. From the crystallographic viewpoint, these InAs nanowires are predominantly of wurtzite structure. Furthermore, we show one possible device application of the aforementioned structure in vertical wrap-gated field-effect transistor geometry. The vertically aligned InAs nanowires are utilized as transistor channels and the InAs epitaxial layer is employed as the source contact. A high uniformity of the device characteristics for numerous transistors is further presented and RF characterization of these devices demonstrates an f(t) of 9.8 GHz.
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| 27. |
- Hoffmann, Erik, et al.
(författare)
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Androgen receptor-beta mRNA levels in different tissues in breeding and post-breeding male and female sticklebacks, Gasterosteus aculeatus
- 2012
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Ingår i: Reproductive Biology and Endocrinology. - : BioMed Central (BMC). - 1477-7827. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Androgens induce male characters by activating androgen receptors (AR). Previous quantitative studies on AR in fishes have been limited to few tissues and/or a single season/reproductive state. The aim of this investigation was to study the possible role of AR-beta expression levels in the control of male traits in the three-spined stickleback. To that end, AR-beta expression levels in major tissues in breeding and post-breeding male and female sticklebacks were examined.METHODS: AR-beta mRNA levels were quantified in ten tissues; eye, liver, axial muscle, heart, brain, intestine, ovary, testis, kidney and pectoral muscle in six breeding and post-breeding males and females using reverse transcription quantitative PCR.RESULTS: Breeding in contrast to post-breeding males built nests and showed secondary sexual characters (e.g. kidney hypertrophy) and elevated androgen levels. Post-breeding females had lower ovarian weights and testosterone levels than breeding females. AR-beta was expressed in all studied tissues in both sexes and reproductive states with the highest expression in the gonads and in the kidneys. The kidney is an androgen target organ in sticklebacks, from which breeding males produce the protein spiggin, which is used in nest-building. There was also high AR-beta expression in the intestine, an organ that appears to take over hyperosmo-regulation in fresh water when the kidney hypertrophies in mature males and largely loses this function. The only tissue that showed effects of sex or reproductive state on AR-beta mRNA levels was the kidneys, where post-breeding males displayed higher AR-beta mRNA levels than breeding males.CONCLUSION: The results indicate that changes in AR-beta mRNA levels play no or little role in changes in androgen dependent traits in the male stickleback.
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| 28. |
- Johansson, Sofia, et al.
(författare)
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High frequency vertical InAs nanowire MOSFETs integrated on Si substrates
- 2012
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Ingår i: Physica Status Solidi. C, Current Topics in Solid State Physics. - : Wiley. - 1610-1634. ; 9:2, s. 350-353
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Tidskriftsartikel (refereegranskat)abstract
- RF and DC characterization of vertical InAs nanowire MOSFET on Si substrates are presented. Nanowire arrays are epitaxially integrated on Si substrates by use of a thin InAs buffer layer. For device fabrication, high-k HfO2 gate dielectric and wrap-gates are used. Post-deposition annealing of the high-k is evaluated by comparing one annealed and one not-annealed sample. The annealed sample show better DC characteristics in terms of transconductance, g(m) = 155 mS/mm, and on-current, I-on = 550 mA/mm. Box plots of on-current, on-resistance and transconductance for all 190-nanowire-array transistors on the annealed sample suggest that the electrical properties of the nanowires are preserved when scaling the nanowire diameter. Finally, high frequency characterisation yields a unity current gain cut-off frequency of f(t) = 9.3 GHz for the annealed sample and f(t) = 2.0 GHz for the not-annealed sample. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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| 29. |
- Johansson, Sofia, et al.
(författare)
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RF Characterization of Vertical InAs Nanowire Wrap-Gate Transistors Integrated on Si Substrates
- 2011
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Ingår i: IEEE Transactions on Microwave Theory and Techniques. - 0018-9480. ; 59:10, s. 2733-2738
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Tidskriftsartikel (refereegranskat)abstract
- We present dc and RF characterization of InAs nanowire field-effect transistors (FETs) heterogeneously integrated on Si substrates in a geometry suitable for circuit applications. The FET consists of an array of 182 vertical InAs nanowires with about 6-nm HfO high-gate dielectric and a wrap-gate length of 250 nm. The transistor has a transconductance of 155 mS/mm and an on-current of 550 mA/mm at a gate voltage of 1.5 V and a drain voltage of 1 V. S-parameter measurements yield an extrinsic cutoff frequency of 9.3 GHz and a extrinsic maximum oscillation frequency of 14.3 GHz.
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| 30. |
- Johansson, Sofia, et al.
(författare)
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Temperature and annealing effects on InAs nanowire MOSFETs
- 2011
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Ingår i: Microelectronic Engineering. - : Elsevier BV. - 0167-9317 .- 1873-5568. ; 88:7, s. 1105-1108
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Konferensbidrag (refereegranskat)abstract
- We report on temperature dependence on the drive current as well as long-term effects of annealing in vertical InAs nanowire Field-Effect Transistors. Negatively charged traps in the HfO2 gate dielectric are suggested as one major factor in explaining the effects observed in the transistor characteristics. An energy barrier may be correlated with an un-gated InAs nanowire region covered with HfO2 and the effects of annealing may be explained by changed charging on defects in the oxide. Initial simulations confirm the general effects on the I-V characteristics by including fixed charge. (c) 2011 Elsevier B.V. All rights reserved.
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| 31. |
- Konings, Annelies, et al.
(författare)
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Association between variations in CAT and noise-induced hearing loss in two independent noise-exposed populations
- 2007
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 16:15, s. 1872-1883
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Tidskriftsartikel (refereegranskat)abstract
- Noise-induced hearing loss (NIHL) is an important occupational hazard that results from an interaction between genetic and environmental factors. Although the environmental risk factors have been studied quite extensively, little is known about the genetic factors. On the basis of multiple studies, it was proposed that oxidative stress plays an important role in the development of NIHL. Here, we investigated whether variations (single nucleotide polymorphisms; SNPs) in the catalase gene (CAT), one of the genes involved in oxidative stress, influence noise susceptibility. Audiometric data from 1261 Swedish and 4500 Polish noise-exposed labourers were analysed. DNA samples were collected from the 10% most susceptible and the 10% most resistant individuals. Twelve SNPs were selected and genotyped. Subsequently, the interaction between noise exposure and genotypes and their effect on NIHL were analysed using logistic regression. Significant interactions were observed between noise exposure levels and genotypes of two SNPs for the Swedish population and of five SNPs for the Polish population. Two of these SNPs were significant in both populations. The interaction between predictor haplotypes and tagSNP haplotypes and noise exposure levels and their effect on NIHL were also analysed, resulting in several significant associations. In conclusion, this study identified significant associations between catalase SNPs and haplotypes and susceptibility to development of NIHL. These results indicate that catalase is a NIHL susceptibility gene, but that the effect of CAT polymorphisms can only be detected when noise exposure levels are taken into account.
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| 32. |
- Konings, Annelies, et al.
(författare)
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Variations in HSP70 genes associated with noise-induced hearing loss in two independent populations
- 2009
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Ingår i: European Journal of Human Genetics. - : Springer Science and Business Media LLC. - 1018-4813 .- 1476-5438. ; 17:3, s. 329-35
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Tidskriftsartikel (refereegranskat)abstract
- Noise-induced hearing loss (NIHL) is one of the most important occupational health hazards. Millions of people worldwide are exposed daily to harmful levels of noise. NIHL is a complex disease resulting from an interaction between genetic and environmental factors. Although the environmental risk factors have been studied extensively, little is known about the genetic factors. Heat-shock proteins (HSPs) are induced after exposure to severe noise. When first induced by exposure to moderate sound levels, they can protect the ear from damage from excessive noise exposure. This protection is highly variable between individuals. An association of HSP70 genes with NIHL has been described by Yang et al (2006) in a Chinese sample set of noise-exposed workers. In this study, three polymorphisms (rs1043618, rs1061581 and rs2227956) in HSP70-1, HSP70-2 and HSP70-hom, respectively, were genotyped in 206 Swedish and 238 Polish DNA samples of noise-exposed subjects and analyzed. One SNP, rs2227956 in HSP70-hom, resulted in a significant association with NIHL in both sample sets. In addition, rs1043618 and rs1061581 were significant in the Swedish sample set. Analysis of the haplotypes composed of the three SNPs revealed significant associations between NIHL and haplotype GAC in both sample sets and with haplotype CGT in the Swedish sample set. In conclusion, this study replicated the association of HSP70 genes with NIHL in a second and third independent noise-exposed sample set, hereby adding to the evidence that HSP70 genes may be NIHL susceptibility genes.
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| 33. |
- Lind, Erik, et al.
(författare)
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High Frequency Performance of Vertical InAs Nanowire MOSFET
- 2010
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Ingår i: 2010 22Nd International Conference On Indium Phosphide And Related Materials (Iprm). - 1092-8669. - 9781424459193
-
Konferensbidrag (refereegranskat)abstract
- We report on RF characterization of vertical, 100-nm-gate length InAs nanowire MOSFETs, utilizing wrap-gate technology and Al2O3 high-kappa gate oxide. The transistors show f(t)=5.6 GHz and f(max)=22 GHz, mainly limited by parasitic capacitances. The RF device performance is described using a hybrid-pi model taking hole generation at the drain into account. Electrostatic modeling of the parasitic capacitances for arrays of vertical nanowires indicates that a strong reduction in extrinsic capacitances can be achieved for devices with a small inter-wire separation.
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| 34. |
- Persson, Karl-Magnus, et al.
(författare)
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Extrinsic and Intrinsic Performance of Vertical InAs Nanowire MOSFETs on Si Substrates
- 2013
-
Ingår i: IEEE Transactions on Electron Devices. - 0018-9383. ; 60:9, s. 2761-2767
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents DC and RF characterization as well as modeling of vertical InAs nanowire MOSFETs with LG = 200 nm and Al2O3/HfO2 high-κ dielectric. Measurements at VDS = 0.5 V show that high transconductance (gm = 1.37 mS/μm), high drive current (IDS = 1.34 mA/μm), and low on-resistance (RON = 287 Ωμm) can be realized using vertical InAs nanowires on Si substrates. By measuring the 1/f-noise, the gate area normalized gate voltage noise spectral density, SVG·LG·WG, is determined to be lowered one order of magnitude compared to similar devices with a high-κ film consisting of HfO2 only. Additionally, with a virtual source model we are able to determine the intrinsic transport properties. These devices (LG = 200 nm) show a high injection velocity (vinj = 1.7·107 cm/s) with a performance degradation for array FETs predominantly due to an increase in series resistance.
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| 35. |
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| 36. |
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| 37. |
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| 38. |
- Van Laer, Lut, et al.
(författare)
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The contribution of genes involved in potassium-recyclingin the inner ear to noise-induced hearing loss
- 2006
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Ingår i: Human Mutation. - : Hindawi Limited. - 1059-7794 .- 1098-1004. ; 27:8, s. 786-795
-
Tidskriftsartikel (refereegranskat)abstract
- Noise-induced hearing loss (NIHL) is one of the most important occupational diseases and, after presbyacusis, the most frequent cause of hearing loss. NIHL is a complex disease caused by an interaction between environmental and genetic factors. The various environmental factors involved in NIHL have been relatively extensively studied. On the other hand, little research has been performed on the genetic factors responsible for NIHL. To test whether the variation in genes involved in coupling of cells and potassium recycling in the inner ear might partly explain the variability in susceptibility to noise, we performed a case-control association study using 35 SNPs selected in 10 candidate genes on a total of 218 samples selected from a population of 1,261 Swedish male noise,exposed workers. We have obtained significant differences between susceptible and resistant individuals for the allele, genotype, and haplotype frequencies for three SNPs of the KCNEI gene, and for the allele frequencies for one SNP of KCNQ1 and one SNP of KCNQ4. Patch-clamp experiments in high K+-concentrations using a Chinese hamster ovary (CHO) cell model were performed to investigate the possibility that the KCNE1-p.85N variant (NT_011512.10:g.21483550G > A; NP_00210.2:p.Asp85Asn) was causative for high noise susceptibility. The normalized current density generated by KCNQ1/KCNE1-p.85N channels, thus containing the susceptibility variant, differed significantly from that from wild-type channels. Furthermore, the midpoint potential of KCNQ1/KCNE1-p.85N channels (i.e., the voltage at which 50% of the channels are open) differed from that of wild-type channels. Further genetic and physiological studies will be necessary to confirm these findings.
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| 39. |
- Zota, Cezar B., et al.
(författare)
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Junctionless tri-gate InGaAs MOSFETs
- 2017
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Ingår i: Japanese Journal of Applied Physics. - 0021-4922. ; 56:12
-
Tidskriftsartikel (refereegranskat)abstract
- We demonstrate and characterize junctionless tri-gate InGaAs MOSFETs, fabricated using a simplified process with gate lengths down to L g = 25 nm at a nanowire dimension of 7 - 16 nm2. These devices use a single 7-nm-thick In0.80Ga0.20As (N D = 1 - 1019 cm-3) layer as both channel and contacts. The devices show SSsat = 76 mV/dec, peak g m = 1.6 mSm and I ON = 160A/m (at I OFF = 100 nA/m and V DD = 0.5 V), the latter which is the highest reported value for a junctionless FET. We also show that device performance is mainly limited by high parasitic access resistance due to the narrow and thin contact layer.
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| 40. |
- Zota, Cezar B., et al.
(författare)
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Record performance for junctionless transistors in InGaAs MOSFETs
- 2017
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Ingår i: 2017 Symposium on VLSI Technology, VLSI Technology 2017. - 9784863486058 ; , s. 34-35
-
Konferensbidrag (refereegranskat)abstract
- We demonstrate junctionless tri-gate MOSFETs utilizing a single layer 7 nm thick In0.80Ga0.20As (ND ∼ 1×1019 cm-3) as both channel and contacts. Devices with source and drain metal separation of 32 nm and Lg of 25 nm exhibit SS = 76 mV/dec., both the highest reported gm = 1.6 mS/μα and Ion = 160 μA/μm (VDD = 0.5 V, IOFF = 100 nA/μm) for a junctionless transistor. We also examine the influence of the contact thickness, comparing double-layer junctionless devices with 37 nm thick contacts with single-layer 7 nm contact devices.
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| 41. |
- Alexandrov, Ludmil B, et al.
(författare)
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The repertoire of mutational signatures in human cancer
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 578:7793, s. 94-101
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Tidskriftsartikel (refereegranskat)abstract
- Somatic mutations in cancer genomes are caused by multiple mutational processes, each of which generates a characteristic mutational signature1. Here, as part of the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium2 of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA), we characterized mutational signatures using 84,729,690 somatic mutations from 4,645 whole-genome and 19,184 exome sequences that encompass most types of cancer. We identified 49 single-base-substitution, 11 doublet-base-substitution, 4 clustered-base-substitution and 17 small insertion-and-deletion signatures. The substantial size of our dataset, compared with previous analyses3-15, enabled the discovery of new signatures, the separation of overlapping signatures and the decomposition of signatures into components that may represent associated-but distinct-DNA damage, repair and/or replication mechanisms. By estimating the contribution of each signature to the mutational catalogues of individual cancer genomes, we revealed associations of signatures to exogenous or endogenous exposures, as well as to defective DNA-maintenance processes. However, many signatures are of unknown cause. This analysis provides a systematic perspective on the repertoire of mutational processes that contribute to the development of human cancer.
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| 42. |
- Alsne, Marianne, et al.
(författare)
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Förord: Sinnena, konsten och vetenskapen
- 2007
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Ingår i: Att se tänka och tolka. - Örebro : Örebro universitet. - 9176685179 ; , s. 7-8
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 43. |
- Astromskas, Gvidas, et al.
(författare)
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Temperature dependence of GaSb overgrowth of tungsten on GaSb (001) substrates using MOVPE
- 2008
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Ingår i: 20th International Conference on Indium Phosphide and Related Materials, 2008. IPRM 2008. - 1092-8669. ; , s. 354-356
-
Konferensbidrag (refereegranskat)abstract
- We demonstrate GaSb overgrowth over tungsten patterns and that selective area epitaxy is achievable in the W/GaSb system. By controlling the facet growth at low temperatures, it is possible to embed a metal grating in a thin layer.
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| 44. |
- Astromskas, Gvidas, et al.
(författare)
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Thin InAs membranes and GaSb buffer layers on GaAs(001) substrates
- 2012
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Ingår i: Journal of Vacuum Science and Technology B. - : American Vacuum Society. - 1520-8567. ; 30:5
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Tidskriftsartikel (refereegranskat)abstract
- Thin InAs layers and membranes are fabricated on GaAs substrates using GaSb buffer layers grown by MOVPE. The quality of the GaSb buffer layers is optimized and epitaxial InAs layers are grown on GaSb layers of various thickness. The best GaSb buffer layers are obtained for a nucleation temperature of 450 degrees C and a subsequent growth temperature of 570 degrees C with a V/III ratio of 3, as confirmed by both the structural (high-resolution XRD, AFM) and electrical (Hall) measurements. Furthermore, a clear relationship between the structural quality of the GaSb and InAs layers is established. Finally, free-standing InAs structures are fabricated where Hall measurements reveal a mobility that depends on the film thickness.
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| 45. |
- Athle, Robin, et al.
(författare)
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Improved Endurance of Ferroelectric HfxZr1–xO2 Integrated on InAs Using Millisecond Annealing
- 2022
-
Ingår i: Advanced Materials Interfaces. - : Wiley. - 2196-7350. ; 9:27
-
Tidskriftsartikel (refereegranskat)abstract
- Ferroelectric HfxZr1–xO2 (HZO) is typically achieved by crystallization of an amorphous thin film via rapid thermal processing (RTP) at time scales of seconds to minutes. For integration on III–V semiconductors, this approach can severely degrade the sensitive HZO/III–V interface. To evaluate whether a reduced thermal budget can improve the interface quality, millisecond duration thermal anneals are utilized using a flash lamp annealer (FLA) on HZO/InAs capacitors. Through thorough electrical characterization such as polarization hysteresis, endurance, and capacitance-voltage measurements, as well as synchrotron-based chemical interface characterization, the FLA and RTP treatments are compared and the FLA results are found in lower interface defect density and higher endurance, but also have generally lower remanent polarization (Pr) compared to RTP. Additionally, ways to achieve high Pr and low interface defect density using multiple lower energy flashes, as well as by pre-crystallization during the ALD growth step are investigated. Using FLA, Pr exceeding 20 µC cm−2 is achieved, with extended endurance properties compared to RTP treatment and a considerably decreased defect density, indicative of a higher quality HZO/InAs interface. This work presents valuable insight into the successful integration of ferroelectric HZO on low thermal budget III–V semiconductors.
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| 46. |
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| 47. |
- Baek, Jeanha, et al.
(författare)
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Engineered mesoporous silica reduces long-term blood glucose and HbA1c, and improves metabolic parameters in prediabetics
- 2022
-
Ingår i: Nanomedicine. - : Future Medicine Ltd. - 1743-5889 .- 1748-6963. ; 17:1, s. 9-22
-
Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate the effect of oral consumption of engineered mesoporous silica particles, SiPore15®, on long-term blood glucose levels and other metabolic parameters in individuals with prediabetes and newly diagnosed Type 2 diabetes. Method: An open-label, single-arm, multicenter trial was conducted in which SiPore15 was consumed three times daily for 12 weeks. Hemoglobin A1c (HbA1c, primary end point) and an array of metabolic parameters were measured at baseline and throughout the trial. Result: SiPore15 treatment significantly reduced HbA1c by a clinically meaningful degree and improved several disease-associated parameters with minimal side effects. Conclusion: The results from this study demonstrate the potential use of SiPore15 as a treatment for prediabetes that may also delay or prevent the onset of Type 2 diabetes.
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| 48. |
- Balciuniene, Jorune, et al.
(författare)
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Alpha-tectorin involvement in hearing disabilities : One gene-two phenotypes
- 1999
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Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 105:3, s. 211-216
-
Tidskriftsartikel (refereegranskat)abstract
- The human alpha-tectorin (TECTA) gene has recently been cloned and proposed to be involved in autosomal dominant non-syndromic hearing impairment (NSHI) in two families linked to the DFNA12 locus. We have studied a Swedish pedigree with autosomal dominant NSHI with possible digenic inheritance of the disease, involving locus DFNA12 in chromosome 11 and locus DFNA2 in chromosome 1. Mutation analysis of the TECTA gene in this family has identified eight nucleotide substitutions indicating that TECTA is highly polymorphic. One of the changes results in a cysteine to serine (C 1057 S) mutation, in the zonadhesin domain of TECTA; this segregates with the disease haplotype on chromosome 11 and is not present in a control population. The mutation results in the replacement of a cysteine in one of the repeats of the zonadhesin/Von Willebrand domain of the protein and might cause a change in the crosslinking of the polypeptide. These findings add support to the involvement of TECTA in hearing disabilities. However, the three families carrying different TECTA mutations also show phenotypic differences: the hearing loss ranges from prelingual to progressive with late onset. The explanation for the different phenotypes and some clues regarding the functions of TECTA may lie in the localization of the mutations in the different modules of the protein. Another possibility is that the phenotype in the Swedish family is the result of two defective genes.
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| 49. |
- Balciuniene, Jorune, et al.
(författare)
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Evidence for digenic inheritance of nonsyndromic hereditary hearing loss in a Swedish family
- 1998
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Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 63:3, s. 786-93
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Tidskriftsartikel (refereegranskat)abstract
- We investigated a Swedish family with nonsyndromic progressive bilateral sensorineural hearing loss. Thirteen candidate loci for autosomal dominant nonsyndromic hearing loss were tested for linkage in this family. We found significant LOD scores (>3) for markers at candidate locus DFNA12 (11q22-q24) and suggestive LOD scores (>2) for markers at locus DFNA2 (1p32). Our results for markers on chromosome 11 narrowed down the candidate region for the DFNA12 locus. A detailed analysis of the phenotypes and haplotypes shared by the affected individuals supported the notion that two genes segregated together with hearing impairment in the family. Severely affected family members had haplotypes linked to the disease allele on both chromosomes 1 and 11, whereas individuals with milder hearing loss had haplotypes linked to the disease allele on either chromosome 1 or chromosome 11. These observations suggest an additive effect of two genes, each gene resulting in a mild and sometimes undiagnosed phenotype, but both together resulting in a more severe phenotype.
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| 50. |
- Bergemalm, Per-Olof, 1951-
(författare)
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Audiologic and cognitive long-term sequelae from closed head injury
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Objectives – Head injury is an important health problem all over the world. Previous studies have shown that peripheral hearing impairment (HI) is a common sequel of closed head injury (CHI), but in most cases it will subside within the first posttraumatic months. However, in some cases, the HI persists and in other cases there can even be progress. The objective of the present study was to analyse long-term audiologic and cognitive consequences of CHI.There were four main issues:1. To study the presence and progress of sensorineural hearing loss (SNHL) after CHI and whether prediction of progress is possible. Autoimmunity as a possible cause of progress is also investigated, and the question of sympathetic cochleolabyrinthitis is discussed.2. To study the presence of central auditory processing disorders (CAPD) after CHI; the question of a King-Kopetzky syndrome should be discussed.3. To study the presence of cognitive impairments.4. To evaluate self-assessed hearing, cognition and quality of life from a long-term perspective.Material and methods – During a period of 14 years, around 2000 patients with head injuries were admitted to the emergency ward at Lindesberg County Hospital and Örebro Medical Centre Hospital. Six hundred subjects suffered from skull fracture and/or brain contusion and diagnosis was established using a computed tomography scan (CT). The degree of initial brain injury was estimated using the Swedish Reaction Level Scale (RLS). Sixty-six subjects were investigated with pure tone audiometry in close proximity to the trauma, and this gave an opportunity to study the issue of progress. The investigation took place two to 14 years after trauma, and the results were compared to matched control groups. A battery of different audiological methods was used to investigate peripheral and central auditory function, and a specially designed acoustic environmental room was also utilized. Cognition was investigated using a computer-based test-battery, text information process system (TIPS). Self-assessed hearing, cognition and quality of life were explored using different questionnaires.Results – A high percentage of peripheral and central auditory impairments and also cognitive shortcomings were demonstrated. Progress of SNHL was a common finding, and fracture, high age at trauma and large initial hearing loss predicted progress. Antibody-mediated autoimmunity as a mechanism behind posttraumatic progress of SNHL or clear evidence for sympathetic cochleolabyrinthitis could not be demonstrated. Binaural auditory deficits could be demonstrated when tested in a realistic acoustic environment. Tinnitus, vertigo and memory shortcomings proved to be common sequelae, even in a long-term perspectiveCognitive shortcomings were found in several of these well-rehabilitated subjects.On a group level, there was a good correlation between self-assessments and audiometric results, even if some individuals had a tendency to over- or underestimate their abilities.Conclusion – Auditory and cognitive long-term sequelae of CHI are a common finding even in well-rehabilitated and socially well-functioning subjects, as are vertigo and tinnitus. Vertigo and tinnitus are also common sequelae after CHI, therefore a basic audiovestibular investigation after CHI is recommended, at least in selected cases.Early awareness of the risk for hearing and cognitive sequelae after CHI could lead to measurements taken to prevent tension-related symptoms.Early detection of HI offers an opportunity to try immunosuppressive treatment in cases with a large initial SNHL.
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