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- Gerkin, Richard C., et al.
(author)
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Recent Smell Loss Is the Best Predictor of COVID-19 Among Individuals With Recent Respiratory Symptoms
- 2021
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In: Chemical Senses. - : Oxford University Press (OUP). - 0379-864X .- 1464-3553. ; 46
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Journal article (peer-reviewed)abstract
- In a preregistered, cross-sectional study, we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0–100 visual analog scales (VAS) for participants reporting a positive (C19+; n = 4148) or negative (C19−; n = 546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19− groups exhibited smell loss, but it was significantly larger in C19+ participants (mean ± SD, C19+: −82.5 ± 27.2 points; C19−: −59.8 ± 37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC = 0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0–10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4 < OR < 10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable.
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2. |
- Parma, Valentina, et al.
(author)
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More Than Smell—COVID-19 Is Associated With Severe Impairment of Smell, Taste, and Chemesthesis
- 2020
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In: Chemical Senses. - : Oxford University Press (OUP). - 0379-864X .- 1464-3553. ; 45:7, s. 609-622
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Journal article (peer-reviewed)abstract
- Recent anecdotal and scientific reports have provided evidence of a link between COVID-19 and chemosensory impairments, such as anosmia. However, these reports have downplayed or failed to distinguish potential effects on taste, ignored chemesthesis, and generally lacked quantitative measurements. Here, we report the development, implementation, and initial results of a multilingual, international questionnaire to assess self-reported quantity and quality of perception in 3 distinct chemosensory modalities (smell, taste, and chemesthesis) before and during COVID-19. In the first 11 days after questionnaire launch, 4039 participants (2913 women, 1118 men, and 8 others, aged 19–79) reported a COVID-19 diagnosis either via laboratory tests or clinical assessment. Importantly, smell, taste, and chemesthetic function were each significantly reduced compared to their status before the disease. Difference scores (maximum possible change ±100) revealed a mean reduction of smell (−79.7 ± 28.7, mean ± standard deviation), taste (−69.0 ± 32.6), and chemesthetic (−37.3 ± 36.2) function during COVID-19. Qualitative changes in olfactory ability (parosmia and phantosmia) were relatively rare and correlated with smell loss. Importantly, perceived nasal obstruction did not account for smell loss. Furthermore, chemosensory impairments were similar between participants in the laboratory test and clinical assessment groups. These results show that COVID-19-associated chemosensory impairment is not limited to smell but also affects taste and chemesthesis. The multimodal impact of COVID-19 and the lack of perceived nasal obstruction suggest that severe acute respiratory syndrome coronavirus strain 2 (SARS-CoV-2) infection may disrupt sensory-neural mechanisms.
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3. |
- Gerkin, RC, et al.
(author)
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The best COVID-19 predictor is recent smell loss: a cross-sectional study
- 2020
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In: medRxiv : the preprint server for health sciences. - : Cold Spring Harbor Laboratory.
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Journal article (other academic/artistic)abstract
- BackgroundCOVID-19 has heterogeneous manifestations, though one of the most common symptoms is a sudden loss of smell (anosmia or hyposmia). We investigated whether olfactory loss is a reliable predictor of COVID-19.MethodsThis preregistered, cross-sectional study used a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified singular and cumulative predictors of COVID-19 status and post-COVID-19 olfactory recovery.ResultsBoth C19+ and C19-groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both single and cumulative feature models (ROC AUC=0.72), with additional features providing negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms, such as fever or cough. Olfactory recovery within 40 days was reported for ∼50% of participants and was best predicted by time since illness onset.ConclusionsAs smell loss is the best predictor of COVID-19, we developed the ODoR-19 tool, a 0-10 scale to screen for recent olfactory loss. Numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4<OR<10), which can be deployed when viral lab tests are impractical or unavailable.
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5. |
- Rashidi, L., et al.
(author)
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Dispersive clean-up process based on a magnetic graphene oxide nanocomposite for determination of 2-glycerol monopalmitate in olive oil prior to GC-FID and GC-MS analysis
- 2022
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In: Journal of the Science of Food and Agriculture. - : Wiley. - 0022-5142 .- 1097-0010. ; 102:3, s. 995-1001
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Journal article (peer-reviewed)abstract
- BACKGROUND: Recently, methods have been developed for the better quality control, fraud detection and analytical investigation of olive oil. Magnetic graphene oxide (GO) material is known for its reusability, high adsorption capability and stability in food sample preparation. Monopalmitine or 2-glycerol monopalmitate (2-GMP) is one of the main parameters in the quality assay and classification of olive oil, which can be classified as extra virgin ≤ 0.9% and olive pomace ≤ 1.2. Hence, newly synthesized magnetic GO (MGO) and commercial silica-gel were used as a dispersive solid-phase clean-up (d-SPE) sorbent to determine 2-GMP value in olive oil samples prior to gas chromatography (GC) analysis. The d-SPE method is validated with olive oil certified reference material (CRM) with respect to silica-gel and a MGO nanocomposite. RESULTS: The developed d-SPE method was applied for various virgin, refined and pomace olive oil samples to determine the value of 2-GMP%. The presence of 2-GMP in the samples was confirmed by GC-mass spectrometry analysis based on silylation derivatives of the analyte. Finally, the d-SPE-MGO method was determined 2-GMP% as 1.9% for pomace olive oil, 0.6% for refined olive oil, 0.4% for virgin olive oil and 3.1% for CRM. The MGO provided satisfactory clean-up recovery (124%) in the acceptable data range for CRM2018, and silica-gel also provided satisfactory recovery (83%) for CRM2018. The proposed method performed with higher sensitivity and efficiency for screening 2-GMP% in olive oil. CONCLUSION: The MGO based d-SPE method was applied for clean-up purposes to determine 2-GMP%. It proved superior via its advantageous features of super quickness, easy isolation with an external magnet and the highly efficient exclusion of all the coexisting interfering peaks conventionally generated with a standard silica-gel material. These methods based on MGO and silica-gel are reflected in the dispersive mode of extraction and can be used as alternatives to conventional methods. Considering the benefits of the consumption of significantly fewer sorbents and less time required regarding the dispersive methods, the methods can be utilized as alternatives in contrast to conventional techniques.
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6. |
- Shi, W., et al.
(author)
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Self-consistent modeling of a transistor vertical-cavity surface-emitting laser
- 2010
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In: 10th International Conference on Numerical Simulation of Optoelectronic Devices, NUSOD 2010. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781424470167 ; , s. 45-46
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Conference paper (peer-reviewed)abstract
- A multiple quantum well (MQW) transistor vertical-cavity surface-emitting laser (T-VCSEL) is designed and numerically modeled. The quantum capture/escape process is simulated using a quantum-trap model. Both the steady state and frequency response of the T-VCSEL are calculated by a numerical and analytical approach.
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7. |
- Zettergren, Henning, et al.
(author)
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Roadmap on dynamics of molecules and clusters in the gas phase
- 2021
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In: European Physical Journal D. - : Springer Science and Business Media LLC. - 1434-6060 .- 1434-6079. ; 75:5
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Journal article (peer-reviewed)abstract
- This roadmap article highlights recent advances, challenges and future prospects in studies of the dynamics of molecules and clusters in the gas phase. It comprises nineteen contributions by scientists with leading expertise in complementary experimental and theoretical techniques to probe the dynamics on timescales spanning twenty order of magnitudes, from attoseconds to minutes and beyond, and for systems ranging in complexity from the smallest (diatomic) molecules to clusters and nanoparticles. Combining some of these techniques opens up new avenues to unravel hitherto unexplored reaction pathways and mechanisms, and to establish their significance in, e.g. radiotherapy and radiation damage on the nanoscale, astrophysics, astrochemistry and atmospheric science.
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