| 1. |
- Moberg, Christina, et al.
(författare)
-
De unga gör helt rätt när de stämmer staten
- 2022
-
Ingår i: Aftonbladet. - 1103-9000.
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
|
|
| 2. |
- Ahmad, Irma, et al.
(författare)
-
High prevalence of persistent symptoms and reduced health-related quality of life 6 months after COVID-19
- 2023
-
Ingår i: Frontiers In Public Health. - : Frontiers Media S.A.. - 2296-2565. ; 11
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The long-term sequelae after COVID-19 constitute a challenge to public health and increased knowledge is needed. We investigated the prevalence of self-reported persistent symptoms and reduced health-related quality of life (HRQoL) in relation to functional exercise capacity, 6 months after infection, and explored risk factors for COVID-19 sequalae.METHODS: This was a prospective, multicenter, cohort study including 434 patients. At 6 months, physical exercise capacity was assessed by a 1-minute sit-to-stand test (1MSTST) and persistent symptoms were reported and HRQoL was evaluated through the EuroQol 5-level 5-dimension (EQ-5D-5L) questionnaire. Patients with both persistent symptoms and reduced HRQoL were classified into a new definition of post-acute COVID syndrome, PACS+. Risk factors for developing persistent symptoms, reduced HRQoL and PACS+ were identified by multivariable Poisson regression.RESULTS: Persistent symptoms were experienced by 79% of hospitalized, and 59% of non-hospitalized patients at 6 months. Hospitalized patients had a higher prevalence of self-assessed reduced overall health (28 vs. 12%) and PACS+ (31 vs. 11%). PACS+ was associated with reduced exercise capacity but not with abnormal pulse/desaturation during 1MSTST. Hospitalization was the most important independent risk factor for developing persistent symptoms, reduced overall health and PACS+.CONCLUSION: Persistent symptoms and reduced HRQoL are common among COVID-19 survivors, but abnormal pulse and peripheral saturation during exercise could not distinguish patients with PACS+. Patients with severe infection requiring hospitalization were more likely to develop PACS+, hence these patients should be prioritized for clinical follow-up after COVID-19.
|
|
| 3. |
- Björnsson, Lars-Henrik, et al.
(författare)
-
Laddinfrastruktur och frekvensreglering : en fallstudie
- 2023
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- För att elnätet ska fungera måste frekvensen hållas inom snäva gränser och därför handlar Svenska Kraftnät upp olika typer av stödtjänster för frekvensreglering. De senaste åren har kostnaderna för dessa tjänster ökat kraftigt, bland annat till följd av en allt högre andel intermittent elproduktion. Behoven är prognostiserade att öka ytterligare under de kommande åren. Detta har skapat ett ökat intresse för batterier och deras möjligheter att stödja elnätet. Men batterier och tillhörande kraftelektronik är kostsamt. Samtidigt finns en stor och alltjämt växande batterikapacitet i landets elbilar och med hjälp av dubbelriktad laddning, så kallad vehicle-to-grid öppnas nya möjligheter att komma åt denna potential för att på ett mer resurseffektivt sätt balansera elnätet. Projektets övergripande mål har varit att utreda hur standardisering kan användas för att påskynda och öka användandet av elbilar som resurs för flexibilitetstjänster till elnätet. Bland annat har en fallstudie genomförts av Axess Logistics anläggning i Malmö hamn och möjligheterna för att deras långtidsparkerade elbilar ska kunna leverera frekvensreglering till elnätet har studerats. Resultaten visar på att studerade standarder i stort inte utgör ett direkt hinder för användandet av elbilar för frekvensreglering men att förändringar av exempelvis ISO15118 skulle kunna öka möjligheterna att använda elbilar för att leverera frekvensreglering. Till exempel genom införande av krav på mätnoggrannhet på aktiv effekt, förkortning av tillåtna svarstider, krav på lokal frekvensmätning med god noggrannhet. För långtidsparkerade bilar vore det framförallt värdefullt att arbeta fram, och i standard beskriva, en funktion där elbilens BMS kan uppmanas av EVSE att hålla batteriet i ett tillstånd där det kan användas för att snabbt svara på en begäran om i-/urladdning. Detta så att elbilen kan vara förberedd för frekvensreglering även om den för stunden inte aktivt laddar eller matar effekt till elnätet. Detta en åtgärd som skulle kunna ha stor positiv påverkan på möjligheterna för långtidsparkerade elbilar att leverera frekvensreglering. Exemplifierande användarcykler för långtidsparkerade bilar har studerats för FCR-N och FCR-D. Resultaten visar att den förväntade cyklingen skiljer stort mellan dessa olika frekvensregleringstjänster och antyder att valet av frekvensregleringstjänst behöver studeras utifrån både förväntad ekonomi och eventuellt batterislitage. Överslagsräkningar på eventuella intäkter från deltagande i frekvensreglering har genomförts och de preliminära resultaten visar att investering av dyrare laddinfrastruktur som klarar Vehicle-to-Grid skulle kunna återbetalas inom ett år med 2022 års nivåer av ersättning för frekvensreglering. I en framtid där nya elbilar antas ha stöd för Vehicle-to-Grid har potentialen för att använda långtidsparkerade elbilar på logistikanläggningar till frekvensreglering preliminärt bedömts ligga mellan 110 och 165 MW för svenska förhållanden. Detta motsvarar ca 5-8% av den nordiska FCR-marknaden. På sikt kan också långtidsparkerade bilar hos återförsäljare, flygplatser med mera att utgöra en betydande potential.
|
|
| 4. |
- Cabrera, Carin C., et al.
(författare)
-
Increased iron absorption in patients with chronic heart failure and iron deficiency
- 2020
-
Ingår i: Journal of Cardiac Failure. - : Elsevier BV. - 1071-9164 .- 1532-8414. ; 26:5, s. 440-443
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Iron deficiency (ID) is common in patients with chronic heart failure (CHF), but the underlying causes are not fully understood. We investigated whether ID is associated with decreased iron absorption in patients with CHF.Methods and Results: We performed an oral iron-absorption test in 30 patients and 12 controls. The patients had CHF with reduced (n = 15) or preserved (n = 15) ejection fraction and ID, defined as s- ferritin < 100 mu g/L, or s-ferritin 100-299 mu g/L and transferrin saturation < 20%. The controls had no HF or ID and were of similar age and gender. Blood samples were taken before and 2 hours after ingestion of 100 mg ferroglycin sulphate. The primary endpoint was the delta plasma iron at 2 hours. The delta plasma iron was higher in the group with HF than in the control group (median increase 83.8 [61.5;128.5] mu g/dL in HF vs 47.5 [ 30.7;61.5] mu g/dL in controls, P = 0.001), indicating increased iron absorption. There was no significant difference between the groups with preserved or reduced ejection fraction (P = 0.46).Conclusion: We found increased iron absorption in patients with CHF and ID compared to controls without ID and HF, indicating that reduced iron absorption is not a primary cause of the high prevalence of ID in patients with CHF.
|
|
| 5. |
- Ding Yuan, Chen, 1991, et al.
(författare)
-
Impact of in situ NH3 pre-treatment of LPCVD SiN passivation on GaN HEMT performance
- 2022
-
Ingår i: Semiconductor Science and Technology. - : IOP Publishing. - 1361-6641 .- 0268-1242. ; 37:3
-
Tidskriftsartikel (refereegranskat)abstract
- The impact on the performance of GaN high electron mobility transistors (HEMTs) of in situ ammonia (NH3) pre-treatment prior to the deposition of silicon nitride (SiN) passivation with low-pressure chemical vapor deposition (LPCVD ) is investigated. Three different NH3 pre-treatment durations (0, 3, and 10 min) were compared in terms of interface properties and device performance. A reduction of oxygen (O) at the interface between SiN and epi-structure is detected by scanning transmission electron microscopy (STEM )-electron energy loss spectroscopy (EELS) measurements in the sample subjected to 10 min of pre-treatment. The samples subjected to NH3 pre-treatment show a reduced surface-related current dispersion of 9% (compared to 16% for the untreated sample), which is attributed to the reduction of O at the SiN/epi interface. Furthermore, NH3 pre-treatment for 10 min significantly improves the current dispersion uniformity from 14.5% to 1.9%. The reduced trapping effects result in a high output power of 3.4 W mm(-1) at 3 GHz (compared to 2.6 W mm(-1) for the untreated sample). These results demonstrate that the in situ NH3 pre-treatment before LPCVD of SiN passivation is critical and can effectively improves the large-signal microwave performance of GaN HEMTs.
|
|
| 6. |
- Frisk, Christoffer, et al.
(författare)
-
Cardiac biopsies reveal differences in transcriptomics between left and right ventricle in patients with or without diagnostic signs of heart failure
- 2024
-
Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 14:1
-
Tidskriftsartikel (refereegranskat)abstract
- New or mild heart failure (HF) is mainly caused by left ventricular dysfunction. We hypothesised that gene expression differ between the left (LV) and right ventricle (RV) and secondly by type of LV dysfunction. We compared gene expression through myocardial biopsies from LV and RV of patients undergoing elective coronary bypass surgery (CABG). Patients were categorised based on LV ejection fraction (EF), diastolic function and NT-proBNP into pEF (preserved; LVEF ≥ 45%), rEF (reduced; LVEF < 45%) or normal LV function. Principal component analysis of gene expression displayed two clusters corresponding to LV and RV. Up-regulated genes in LV included natriuretic peptides NPPA and NPPB, transcription factors/coactivators STAT4 and VGLL2, ion channel related HCN2 and LRRC38 associated with cardiac muscle contraction, cytoskeleton, and cellular component movement. Patients with pEF phenotype versus normal differed in gene expression predominantly in LV, supporting that diastolic dysfunction and structural changes reflect early LV disease in pEF. DKK2 was overexpressed in LV of HFpEF phenotype, potentially leading to lower expression levels of β-catenin, α-SMA (smooth muscle actin), and enhanced apoptosis, and could be a possible factor in the development of HFpEF. CXCL14 was down-regulated in both pEF and rEF, and may play a role to promote development of HF.
|
|
| 7. |
- Hage, Camilla, et al.
(författare)
-
Metabolomic Profile in HFpEF vs HFrEF Patients
- 2020
-
Ingår i: Journal of Cardiac Failure. - : Elsevier BV. - 1071-9164 .- 1532-8414. ; 26:12, s. 1050-1059
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Heart failure with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) are associated with metabolic derangements, which may have different pathophysiological implications.Methods and Results: In new-onset HFpEF (EF of >= 50%, n = 46) and HFrEF (EF of <40%, n = 75) patients, 109 endogenous plasma metabolites including amino acids, phospholipids and acylcarnitines were assessed using targeted metabolomics. Differentially altered metabolites and associations with clinical characteristics were explored. Patients with HFpEF were older, more often female with hypertension, atrial fibrillation, and diabetes compared with patients with HFrEF. Patients with HFpEF displayed higher levels of hydroxyproline and symmetric dimethyl arginine, alanine, cystine, and kynurenine reflecting fibrosis, inflammation and oxidative stress. Serine, cGMP, cAMP, L-carnitine, lysophophatidylcholine (18:2), lactate, and arginine were lower compared with patients with HFrEF. In patients with HFpEF with diabetes, kynurenine was higher (P = .014) and arginine lower (P = .014) vs patients with no diabetes, but did not differ with diabetes status in HFrEF. Decreasing kynurenine was associated with higher eGFR only in HFpEF (P-interaction = .020).Conclusions: Patients with new-onset HFpEF compared with patients with new-onset HFrEF display a different metabolic profile associated with comorbidities, such as diabetes and kidney dysfunction. HFpEF is associated with indices of increased inflammation and oxidative stress, impaired lipid metabolism, increased collagen synthesis, and downregulated nitric oxide signaling. Together, these findings suggest a more predominant systemic microvascular endothelial dysfunction and inflammation linked to increased fibrosis in HFpEF compared with HFrEF.
|
|
| 8. |
- Linde, Cecilia, et al.
(författare)
-
Baseline characteristics of 547 new onset heart failure patients in the PREFERS heart failure study
- 2022
-
Ingår i: ESC Heart Failure. - : John Wiley & Sons. - 2055-5822. ; 9:4, s. 2125-2138
-
Tidskriftsartikel (refereegranskat)abstract
- Aim We present the baseline characteristics of the PREFERS Stockholm epidemiological study on the natural history and course of new onset heart failure (HF) aiming to improve phenotyping focusing on HF with preserved left ventricular ejection fraction (HFpEF) pathophysiology.Methods and results New onset HF patients diagnosed in hospital or at outpatient HF clinics were included at five Stockholm hospitals 2015-2018 and characterized by N-terminal pro brain natriuretic peptide (NT-proBNP), biomarkers, echocardiography, and cardiac magnetic resonance imaging (subset). HFpEF [left ventricular ejection fraction (LVEF) >= 50%) was compared with HF with mildly reduced LVEF (HFmrEF; LVEF 41-49%) and with HF with reduced LVEF (HFrEF; LVEF <= 40%). We included 547 patients whereof HFpEF (n = 137; 25%), HFmrEF (n = 61; 11%), and HFrEF (n = 349; 64%). HFpEF patients were older (76; 70-81 years; median; interquartile range) than HFrEF (67; 58-74; P < 0.001), more often women (49% vs. 30%; P < 0.001), and had significantly higher comorbidity burden. They more often had atrial fibrillation, hypertension, and renal dysfunction. NT-proBNP was lower in HFpEF (896; 462-1645 ng/L) than in HFrEF (1160; 563-2370; P = 0.005). In HFpEF, left ventricular (LV) diameters and volumes were smaller (P < 0.001) and septa! and posterior wall thickness and relative wall thickness higher (P < 0.001). E/e >= 14 was present in 26% of HFpEF vs. 32% of HFrEF (P = 0.017) and left atrial volume index > 34 mL/m(2) in 57% vs. 61% (P = 0.040). HFmrEF patients were intermediary between HFpEF and HFrEF for LV mass, LV volumes, and RV volumes but had the highest proportion of left ventricular hypertrophy and the lowest proportion of elevated E/e.Conclusions Phenotype data in new onset HF patients recruited in a broad clinical setting showed that 25% had HFpEF, were older, more often women, and had greater comorbidity burden. PREFERS is well suited to further explore biomarker and imaging components of HFpEF pathophysiology and may contribute to the emerging knowledge of HF epidemiology.
|
|
| 9. |
- Matan, Dmitri, et al.
(författare)
-
Extracellular vesicles in heart failure : A study in patients with heart failure with preserved ejection fraction or heart failure with reduced ejection fraction characteristics undergoing elective coronary artery bypass grafting
- 2022
-
Ingår i: Frontiers in Cardiovascular Medicine. - : Frontiers Media S.A.. - 2297-055X. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- AimsExtracellular vesicles (EVs) were investigated as potential biomarkers associated with heart failure (HF) pathophysiology in patients undergoing elective coronary artery bypass surgery characterized by HF phenotype. Materials and methodsPatients with preoperative proxy-diagnoses of HF types i.e., preserved (HFpEF; n = 19) or reduced ejection fraction (HFrEF; n = 20) were studied and compared to patients with normal left ventricular function (n = 42). EVs in plasma samples collected from the coronary sinus, an arterial line, and from the right atrium were analyzed by flow cytometry. We studied EVs of presumed cardiomyocyte origin [EVs exposing Connexin-43 + Caveolin-3 (Con43 + Cav3) and Connexin-43 + Troponin T (Con43 + TnT)], of endothelial origin [EVs exposing VE-Cadherin (VE-Cad)] and EVs exposing inflammatory markers [myeloperoxidase (MPO) or pentraxin3 (PTX3)]. ResultsMedian concentrations of EVs exposing Con43 + TnT and Con43 + Cav3 were approximately five to six times higher in coronary sinus compared to radial artery indicative of cardiac release. Patients with HFrEF had high trans-coronary gradients of both Con43 + TnT and Con43 + Cav3 EVs, whereas HFpEF had elevated gradients of Con43 + Cav3 EVs but lower gradients of Con43 + TnT. Coronary sinus concentrations of both Con43 + TnT and Con43 + Cav3 correlated significantly with echocardiographic and laboratory measures of HF. MPO-EV concentrations were around two times higher in the right atrium compared to the coronary sinus, and slightly higher in HFpEF than in HFrEF. EV concentrations of endothelial origin (VE-Cad) were similar in all three patient groups. ConclusionCon43 + TnT and Con43 + Cav3 EVs are released over the heart indicating cardiomyocyte origin. In HFrEF the EV release profile is indicative of myocardial injury and myocardial stress with elevated trans-coronary gradients of both Con43 + TnT and Con43 + Cav3 EVs, whereas in HFpEF the profile indicates myocardial stress with less myocardial injury.
|
|
| 10. |
- Papamichail, A., et al.
(författare)
-
Compositionally graded channel HEMTs towards improved linearity for low-noise RF amplifiers
- 2022
-
Ingår i: 2022 Compound Semiconductor Week, CSW 2022.
-
Konferensbidrag (refereegranskat)abstract
- Although AlGaN/GaN HEMTs with high power and current gain have been demonstrated in RF device applications, at high signal operation they show an inherent non-linear behavior which leads to gain compression and signal distortion. Polarization-doped AlGaN/GaN HEMTs, with a compositionally graded channel enables a linear response improvement through formation of a 3-D electron gas. In this work, we develop the growth process for graded channel HEMTs in a hot-wall MOCVD reactor. Control of the grading profile is established through growth parameter tuning. Afterwards, analysis by EDS allows for precise determination of Al composition across the channel. Conventional and graded channel HEMT structures were fabricated and characterized. Furthermore, the sheet resistance, carrier density and mobility in HEMT structures with different grading profiles are compared and discussed. The conventional (non-graded) structure revealed the highest electron mobility of ~2350 cm2/V.s, which is among the highest values reported.
|
|
| 11. |
- Persson, Anton E.O., et al.
(författare)
-
Reduced annealing temperature for ferroelectric HZO on InAs with enhanced polarization
- 2020
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 116:6
-
Tidskriftsartikel (refereegranskat)abstract
- Deposition, annealing, and integration of ferroelectric Hf x Zr 1 - x O 2 (HZO) thin films on the high-mobility semiconductor InAs using atomic layer deposition are investigated. Electrical characterization reveals that the HZO films on InAs exhibit an enhanced remanent polarization compared to films formed on a reference TiN substrate, exceeding 20 μ C / cm 2 even down to an annealing temperature of 370 °C. For device applications, the thermal processes required to form the ferroelectric HZO phase must not degrade the high-κ/InAs interface. We find by evaluation of the capacitance-voltage characteristics that the electrical properties of the high-κ/InAs are not significantly degraded by the annealing process, and high-resolution transmission electron microscopy verifies a maintained sharp high-κ/InAs interface.
|
|
| 12. |
- Persson, P. O.Å., et al.
(författare)
-
Tuning composition in graded AlGaN channel HEMTs toward improved linearity for low-noise radio-frequency amplifiers
- 2023
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 122:15
-
Tidskriftsartikel (refereegranskat)abstract
- Compositionally graded channel AlGaN/GaN high electron mobility transistors (HEMTs) offer a promising route to improve device linearity, which is necessary for low-noise radio-frequency amplifiers. In this work, we demonstrate different grading profiles of a 10-nm-thick AlxGa1-xN channel from x = 0 to x = 0.1 using hot-wall metal-organic chemical vapor deposition (MOCVD). The growth process is developed by optimizing the channel grading and the channel-to-barrier transition. For this purpose, the Al-profiles and the interface sharpness, as determined from scanning transmission electron microscopy combined with energy-dispersive x-ray spectroscopy, are correlated with specific MOCVD process parameters. The results are linked to the channel properties (electron density, electron mobility, and sheet resistance) obtained by contactless Hall and terahertz optical Hall effect measurements coupled with simulations from solving self-consistently Poisson and Schrödinger equations. The impact of incorporating a thin AlN interlayer between the graded channel and the barrier layer on the HEMT properties is investigated and discussed. The optimized graded channel HEMT structure is found to have similarly high electron density (∼9 × 10 12 cm-2) as the non-graded conventional structure, though the mobility drops from ∼ 2360 cm2/V s in the conventional to ∼ 960 cm2/V s in the graded structure. The transconductance gm of the linearly graded channel HEMTs is shown to be flatter with smaller g m ′ and g m ″ as compared to the conventional non-graded channel HEMT implying improved device linearity.
|
|
| 13. |
- Aboulfadl, Hisham, 1986, et al.
(författare)
-
Alkali Dispersion in (Ag,Cu)(In,Ga)Se2 Thin Film Solar Cells - Insight from Theory and Experiment
- 2021
-
Ingår i: ACS Applied Materials & Interfaces. - : American Chemical Society (ACS). - 1944-8252 .- 1944-8244. ; 13:6, s. 7188-7199
-
Tidskriftsartikel (refereegranskat)abstract
- Silver alloying of Cu(In,Ga)Se2 absorbers for thin film photovoltaics offers improvements in open-circuit voltage, especially when combined with optimal alkali-treatments and certain Ga concentrations. The relationship between alkali distribution in the absorber and Ag alloying is investigated here, combining experimental and theoretical studies. Atom probe tomography analysis is implemented to quantify the local composition in grain interiors and at grain boundaries. The Na concentration in the bulk increases up to ∼60 ppm for [Ag]/([Ag] + [Cu]) = 0.2 compared to ∼20 ppm for films without Ag and up to ∼200 ppm for [Ag]/([Ag] + [Cu]) = 1.0. First-principles calculations were employed to evaluate the formation energies of alkali-on-group-I defects (where group-I refers to Ag and Cu) in (Ag,Cu)(In,Ga)Se2 as a function of the Ag and Ga contents. The computational results demonstrate strong agreement with the nanoscale analysis results, revealing a clear trend of increased alkali bulk solubility with the Ag concentration. The present study, therefore, provides a more nuanced understanding of the role of Ag in the enhanced performance of the respective photovoltaic devices.
|
|
| 14. |
- Athle, Robin, et al.
(författare)
-
Effects of TiN Top Electrode Texturing on Ferroelectricity in Hf1-xZrxO2
- 2021
-
Ingår i: ACS applied materials & interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 13:9, s. 11089-11095
-
Tidskriftsartikel (refereegranskat)abstract
- Ferroelectric memories based on hafnium oxide are an attractive alternative to conventional memory technologies due to their scalability and energy efficiency. However, there are still many open questions regarding the optimal material stack and processing conditions for reliable device performance. Here, we report on the impact of the sputtering process conditions of the commonly used TiN top electrode on the ferroelectric properties of Hf1-xZrxO2. By manipulating the deposition pressure and chemistry, we control the preferential orientation of the TiN grains between (111) and (002). We observe that (111) textured TiN is superior to (002) texturing for achieving high remanent polarization (Pr). Furthermore, we find that additional nitrogen supply during TiN deposition leads to >5× greater endurance, possibly by limiting the scavenging of oxygen from the Hf1-xZrxO2 film. These results help explain the large Pr variation reported in the literature for Hf1-xZrxO2/TiN and highlights the necessity of tuning the top electrode of the ferroelectric stack for successful device implementation.
|
|
| 15. |
- Athle, Robin, et al.
(författare)
-
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.
|
|
| 16. |
- Athle, Robin, et al.
(författare)
-
Top Electrode Engineering for Freedom in Design and Implementation of Ferroelectric Tunnel Junctions Based on Hf1- xZrxO2
- 2022
-
Ingår i: ACS Applied Electronic Materials. - : American Chemical Society (ACS). - 2637-6113. ; 4:3, s. 1002-1009
-
Tidskriftsartikel (refereegranskat)abstract
- Ferroelectric tunnel junctions (FTJs) based on ultrathin HfO2 have great potential as a fast and energy-efficient memory technology compatible with complementary metal oxide semiconductors. FTJs consist of a ferroelectric film sandwiched between two distinct electrodes, the properties of which are intricately linked to the electrical properties of the FTJs. Here we utilize a W crystallization electrode (CE) to achieve a high and reproducible remanent polarization, combined with a metal replacement process in which the W is carefully removed and replaced by another top electrode (TE). In this way we separate the ferroelectric film properties from the device design and can thereby evaluate the effect of the TE work function (WF) and conduction band electron density (ne) on the tunneling electroresistance (TER) and device reliability. We compare FTJs designed with a TiN bottom electrode and W, Cr, or Ni TE and find that the use of high electron density metals such as Ni or Cr as TE allows for an improved TER, albeit at the cost of reliability due to a large built-in electric field. To bypass this effect, a bilayer Cr/Ni TE is implemented, which allows for a high TER and minimal built-in field, leading to excellent retention and endurance beyond 108 cycles. The results presented here thus highlight a process flow for reliable design and implementation of FTJs.
|
|
| 17. |
- Bäckberg, Matilda, et al.
(författare)
-
Using in vitro receptor activity studies of synthetic cannabinoids to support the risk assessment of new psychoactive substances – A Swedish strategy to protect public health from harm
- 2023
-
Ingår i: Forensic Science International. - : Elsevier Ireland Ltd. - 0379-0738 .- 1872-6283. ; 348
-
Tidskriftsartikel (refereegranskat)abstract
- In the past 15 years, close to 1000 of new psychoactive substances (NPS) have been reported in Europe and globally. At the time of identification, data on safety, toxicity and carcinogenic potential of many NPS are not available or very limited. To work more efficiently, a strategy and collaboration between the Public Health Agency of Sweden (PHAS) and the National Board of Forensic Medicine was established involving in vitro receptor activity assays to demonstrate neurological activity of NPS. This report summarizes the first results on the synthetic cannabinoid receptor agonists (SCRAs), and subsequent actions taken by PHAS. A total of 18 potential SCRAs were selected by PHAS for in vitro pharmacological characterization. 17 compounds could be acquired and investigated for their activity on the human cannabinoid-1 (CB1) receptors expressed together with the AequoScreen system in CHO-K1 cells. Dose-response curves were established using eight different concentrations in triplicates at three occasions with JWH-018 as reference. For the MDMB-4en-PINACA, MMB-022, ACHMINACA, ADB-BUTINACA, 5F-CUMYL-PeGACLONE, 5C-AKB48, NM-2201, 5F-CUMYL-PINACA, JWH-022, 5Cl-AB-PINACA, MPhP-2201, 5F-AKB57 the half maximal effective concentration values ranged from 2.2 nM (5F-CUMYL-PINACA) to 171 nM (MMB-022). EG-018 and 3,5-AB-CHMFUPPYCA were none-active. The results contributed to 14 of these compounds being scheduled as narcotics in Sweden. In conclusion, many of the emerging SCRAs are potent activators of the CB1 receptor in vitro, although some lack activity or are partial agonists. The new strategy proved useful when data on psychoactive effects of the SCRAs under investigation were not available or limited. © 2023 The Authors
|
|
| 18. |
- Chamorro, Harold, et al.
(författare)
-
Nadir Frequency Estimation in Low-Inertia Power Systems
- 2020
-
Ingår i: IEEE International Symposium on Industrial Electronics. - : Institute of Electrical and Electronics Engineers Inc.. - 9781728156354 ; , s. 918-922
-
Konferensbidrag (refereegranskat)abstract
- Increasing amounts of non-synchronous generation in power grids are bringing reductions in system inertia. In a grid with extremely low inertia, the estimation of frequency indicators such as the frequency nadir can be used to feed into predictive system controls that would avoid nuisances such as triggering system protection systems, avoiding needless blackouts. In this paper, the timing of a frequency nadir is predicted using a Nonlinear Auto-Regressive (NAR) model based on an Artificial Neural Network (ANN). The estimation method is tested under a gradual inertia reduction in order to observe the adaptability of the method, under various prediction horizons.
|
|
| 19. |
- Chamorro, H. R., et al.
(författare)
-
Data-driven trajectory prediction of grid power frequency based on neural models
- 2021
-
Ingår i: Electronics. - : MDPI AG. - 2079-9292. ; 10:2
-
Tidskriftsartikel (refereegranskat)abstract
- Frequency in power systems is a real-time information that shows the balance between generation and demand. Good system frequency observation is vital for system security and pro-tection. This paper analyses the system frequency response following disturbances and proposes a data-driven approach for predicting it by using machine learning techniques like Nonlinear Autoregressive (NAR) Neural Networks (NN) and Long Short Term Memory (LSTM) networks from simulated and measured Phasor Measurement Unit (PMU) data. The proposed method uses a horizon-window that reconstructs the frequency input time-series data in order to predict the frequency features such as Nadir. Simulated scenarios are based on the gradual inertia reduction by including non-synchronous generation into the Nordic 32 test system, whereas the PMU collected data is taken from different locations in the Nordic Power System (NPS). Several horizon-windows are experimented in order to observe an adequate margin of prediction. Scenarios considering noisy signals are also evaluated in order to provide a robustness index of predictability. Results show the proper performance of the method and the adequate level of prediction based on the Root Mean Squared Error (RMSE) index. © 2021 by the authors.
|
|
| 20. |
- Deventer, Marie H., et al.
(författare)
-
In vitro cannabinoid activity profiling of generic ban-evading brominated synthetic cannabinoid receptor agonists and their analogs
- 2024
-
Ingår i: Drug Testing and Analysis. - : WILEY. - 1942-7603 .- 1942-7611. ; 16:6, s. 616-628
-
Tidskriftsartikel (refereegranskat)abstract
- Following the enactment of a generic ban in China in 2021, the synthetic cannabinoid market has been evolving, now encompassing even wider structural diversity. Compounds carrying a brominated core such as ADB-5 Br-BUTINACA (ADMB-B-5Br-INACA) and tail-less analogs, such as ADB-5 Br-INACA (ADMB-5Br-INACA), MDMB-5 Br-INACA, and ADB-INACA (ADMB-INACA), have been detected since late 2021. This study investigated the cannabinoid receptor (CB) activation potential of synthesized (S)-enantiomers of these substances, as well as of two predicted analogs MDMB-5 Br-BUTINACA (MDMB-B-5Br-INACA) and ADB-5 F-BUTINACA (ADMB-B-5F-INACA), using CB1 and CB2 beta-arrestin 2 recruitment assays and a CB1 intracellular calcium release assay. Surprisingly, the tail-less (S)-ADB-5 Br-INACA and (S)-MDMB-5 Br-INACA retained CB activity, albeit with a decreased potency compared to their tailed counterparts (S)-ADB-5 Br-BUTINACA and (S)-MDMB-5 Br-BUTINACA, respectively, which were potent and efficacious CB1 agonists. Also, at CB2, tail-less analogs showed a lower potency but increased efficacy. Removing the bromine substitution ((S)-ADB-INACA) resulted in a reduced activity at CB1; however, this effect was less prominent at CB2. Looking at tailed analogs, replacing the bromine with a fluorine substitution ((S)-ADB-5 F-BUTINACA) resulted in an increased potency and efficacy at both receptors. Furthermore, as ADB-5 Br-INACA and MDMB-5 Br-INACA have been frequently detected together in Scottish prisons, this study also evaluated the CB1 receptor activation potential of different mixtures of their respective reference standards, showing no unexpected cannabimimetic effect of combining both substances. Lastly, two powders seized by Belgian Customs and confirmed to contain ADB-5 Br-INACA and MDMB-5 Br-INACA, respectively, were assessed for CB activity. Based on the comparison with their reference standards, varying degrees of purity were suspected. The enactment of the Chinese generic ban (2021) has majorly impacted the SCRA market, exemplified by the recent emergence of tail-less compounds and substances with a brominated core. CB1 and CB2 cannabinoid activity of six analogs was assessed using beta arr2 recruitment and Ca2+ release assays. Absence of a tail moiety still yielded cannabinoid activity albeit with lower potency, whereas tailed analogs were highly efficacious.image
|
|
| 21. |
- Deventer, Marie H., et al.
(författare)
-
Off-target activity of NBOMes and NBOMe analogs at the mu opioid receptor
- 2023
-
Ingår i: Archives of Toxicology. - : SPRINGER HEIDELBERG. - 0340-5761 .- 1432-0738. ; 97:5, s. 1367-1384
-
Tidskriftsartikel (refereegranskat)abstract
- New psychoactive substances (NPS) are introduced on the illicit drug market at a rapid pace. Their molecular targets are often inadequately elucidated, which contributes to the delayed characterization of their pharmacological effects. Inspired by earlier findings, this study set out to investigate the mu opioid receptor (MOR) activation potential of a large set of psychedelics, substances which typically activate the serotonin (5-HT2A) receptor as their target receptor. We observed that some substances carrying the N-benzyl phenethylamine (NBOMe) structure activated MOR, as confirmed by both the NanoBiT (R) beta arr2 recruitment assay and the G protein-based AequoScreen (R) Ca2+ release assay. The use of two orthogonal systems proved beneficial as some aspecific, receptor independent effects were found for various analogs when using the Ca2+ release assay. The specific off-target effects at MOR could be blocked by the opioid antagonist naloxone, suggesting that these NBOMes occupy the same common opioid binding pocket as conventional opioids. This was corroborated by molecular docking, which revealed the plausibility of multiple interactions of 25I-NBOMe with MOR, similar to those observed for opioids. Additionally, structure-activity relationship findings seen in vitro were rationalized in silico for two 25I-NBOMe isomers. Overall, as MOR activity of these psychedelics was only noticed at high concentrations, we consider it unlikely that for the tested compounds there will be a relevant opioid toxicity in vivo at physiologically relevant concentrations. However, small modifications to the original NBOMe structure may result in a panel of more efficacious and potent MOR agonists, potentially exhibiting a dual MOR/5-HT2A activation potential.
|
|
| 22. |
- Eriksson, Mattias, et al.
(författare)
-
Quantities and quantification methodologies of food waste in Swedish hospitals
- 2020
-
Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- To move towards a sustainable food system, we cannot continue to waste substantial amounts of the food produced. This is especially true for later stages in the food supply chain, where most sub-processes consume resources in vain when food is wasted. Hospitals are located at the end of the food supply chain and the sector has high levels of food waste. This study investigated food waste quantification practices in Swedish hospitals, examined whether a questionnaire is an appropriate methodology for such mapping, and compiled data for the sector in order to determine the amount of food waste and its composition. A questionnaire was sent to all 21 regional authorities, formerly known as county councils, responsible for hospitals in Sweden. The questionnaire responses were supplemented with food waste records from three regions that organize the catering in a total of 20 hospitals. The results showed that it is common practice in most hospitals to quantify food waste, with quantification focusing on lunch and dinner in relation to the number of guests served. It was also clear that waste quantification practices have been established for years, and in the majority of the hospitals studied. The data revealed that, in comparison with other sectors, food waste was still high, 111 g guest(-1) meal(-1), consisting of 42% plate waste, 36% serving waste, and 22% kitchen waste. However, there was great variation between hospitals, which, in combination with well-established, standardized waste quantification routines, meaning that this sector has strong potential to spread best practices and improve overall performance in reducing food waste generation.
|
|
| 23. |
- Ewerlöf, Sofia, et al.
(författare)
-
DN Debatt. ”Låt gräsklipparen stå – för naturens skull”
- 2023
-
Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- In an era of species extinction and climate change, we should abandon the well-trimmed lawn and let gardens grow wilder, writes Anna Persson and other researchers and landscape architects on DN Debatt.
|
|
| 24. |
- Fredriksson, Sofie, 1983, et al.
(författare)
-
The Impact of Occupational Noise Exposure on Hyperacusis: a Longitudinal Population Study of Female Workers in Sweden.
- 2021
-
Ingår i: Ear and Hearing. - 1538-4667. ; 43:4, s. 1366-1377
-
Tidskriftsartikel (refereegranskat)abstract
- The aim was to assess the risk of hyperacusis in relation to occupational noise exposure among female workers in general, and among women working in preschool specifically.A retrospective longitudinal study was performed. Survey data were collected in 2013 and 2014 from two cohorts: randomly selected women from the population in region Västra Götaland, Sweden, and women selected based on having received a preschool teacher degree from universities in the same region. The final study sample included n = 8328 women born between 1948 and 1989. Occupational noise exposure was objectively assigned to all time periods from the first to the last reported occupation throughout working life, using the Swedish Job-Exposure Matrix (JEM) with three exposure intervals: <75 dB(A), 75 to 85 dB(A), and >85 dB(A). The JEM assigns preschool teachers to the 75 to 85 dB(A) exposure interval. The outcome hyperacusis was assessed by self-report using one question addressing discomfort or pain from everyday sounds. In the main analysis, a hyperacusis event was defined by the reported year of onset, if reported to occur at least a few times each week. Additional sensitivity analyses were performed using more strict definitions: (a) at least several times each week and (b) every day. The risk (hazard ratio, HR) of hyperacusis was analyzed in relation to years of occupational noise exposure, using survival analysis with frailty regression modeling accounting for individual variation in survival times which reflect, for example, noise exposure during years prior to onset. Occupational noise exposure was defined by the occupation held at year of hyperacusis onset, or the occupation held at the survey year if no event occurred. Models were adjusted for confounders including age, education, income, family history of hearing loss, and change of jobs due to noise.In total, n = 1966 hyperacusis events between 1960 and 2014 were analyzed in the main analysis. A significantly increased risk of hyperacusis was found among women working in any occupation assigned to the 75 to 85 dB(A) noise exposure group [HR: 2.6, 95% confidence interval (CI): 2.4-2.9], compared with the reference group <75 dB(A). The risk was tripled among preschool teachers specifically (HR: 3.4, 95% CI: 3.0-3.7), with the crude Kaplan-Meier curve showing a higher rate of onset early in the working life in preschool teachers compared with all the other exposure groups. The risk was increased, but not statistically significant in the main analysis, for the highest exposure group >85 dB(A), where only six hyperacusis events were identified (HR: 1.4, 95% CI: 0.6-3.1). In the sensitivity analysis, where hyperacusis was defined as occurring every day, the HR was significant also in the highest exposure group (HR: 3.8, 95% CI: 1.4-10.3), and generally slightly higher in the other exposure groups compared to the main analysis.This study indicates increased risk of hyperacusis already below the permissible occupational noise exposure limit in Sweden (85 dB LAeq,8h) among female workers in general, and in particular among preschool teachers. Prospective studies and less wide exposure intervals could confirm causal effects and assess dose-response relationships, respectively, although this study at present suggest a need for risk assessment, improved hearing prevention measures, and noise abatement measures in occupations with noise levels from 75 dB(A). The results could also have implications for management of occupational disability claims.
|
|
| 25. |
|
|
