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BACKGROUND: Early identification of deficits in our ability to perceive odors is important as many normal (i.e., aging) and pathological (i.e., sinusitis, viral, neurodegeneration) processes can result in diminished olfactory function. To realistically enable population-level measurements of olfaction, validated olfaction tests must be capable of being administered outside the research laboratory and clinical setting. AIM: The purpose of this study was to determine the feasibility of remotely testing olfactory performance using a test that was developed with funding from the National Institutes of Health as part of a ready-to-use, non-proprietary set of measurements useful for epidemiologic studies (NIH Toolbox Odor ID Test). MATERIALS AND METHODS: Eligible participants older than 39 years and active (within 6 months) in the Brain Health Registry (BHR), an online cognitive assessment platform which connects participants with researchers, were recruited for this study. Interested participants were mailed the NIH Toolbox Odor ID Test along with instructions on accessing a website to record their responses. Data obtained from subjects who performed the test at home was compared to the normative data collected when the NIH Toolbox Odor ID Test was administered by a tester in a research setting and validated against the Smell Identification Test. The age-range and composition of the population ensured we had the ability to observe both age-related decline and gender-related deficits in olfactory ability, as shown in the experimental setting. RESULTS: We observed that age-associated olfactory decline and gender-associated performance was comparable to performance on the administered test. Self-administration of this test showed the age-related loss in olfactory acuity, F(4, 1156)=14.564, p

This study examines the association between club membership and marathon performance using a dataset of 206,653 London Marathon runners. Our results show a statistically significant association between club membership and marathon performance for both males and females which sees club membership potentially mitigating pace decline with age and resulting in substantial improvements in finishing times of up to 40 minutes. We implement a production function framework and align with three principles of economic organisation. The findings have relevance for marathon participants, coaches, and athletic associations as well as implications beyond athletics to other sports or cooperative activities. [ABSTRACT FROM AUTHOR]

Background: More than a year after recovering from COVID-19, a large proportion of individuals, many of whom work in the healthcare sector, still report olfactory dysfunctions. However, olfactory dysfunction was common already before the COVID-19 pandemic, making it necessary to also consider the existing baseline prevalence of olfactory dysfunction. To establish the adjusted prevalence of COVID-19 related olfactory dysfunction, we assessed smell function in healthcare workers who had contracted COVID‐19 during the first wave of the pandemic using psychophysical testing. Methods: Participants were continuously tested for SARS‐CoV‐2 IgG antibodies since the beginning of the pandemic. To assess the baseline rate of olfactory dysfunction in the population and to control for the possibility of skewed recruitment of individuals with prior olfactory dysfunction, consistent SARS-CoV‐2 IgG naïve individuals were tested as a control group. Results: Fifteen months after contracting COVID‐19, 37% of healthcare workers demonstrated a quantitative reduction in their sense of smell, compared to only 20% of the individuals in the control group. Fifty-one percent of COVID‐19‐recovered individuals reported qualitative symptoms, compared to only 5% in the control group. In a follow-up study 2.6 years after COVID-19 diagnosis, 24% of all tested recovered individuals still experienced parosmia. Conclusions: In summary, 65% of healthcare workers experienced parosmia/hyposmia 15 months after contracting COVID-19. When compared to a control group, the prevalence of olfactory dysfunction in the population increased by 41 percentage points. Parosmia symptoms were still lingering two-and-a half years later in 24% of SARS-CoV-2 infected individuals. Given the amount of time between infection and testing, it is possible that the olfactory problems may not be fully reversible in a plurality of individuals. [ABSTRACT FROM AUTHOR]

Background: Most patients with COVID-19 report experiencing one or more symptoms after acute infection subsides, known as post-acute sequelae of SARS-CoV-2 infection (PASC). Though research has examined PASC after acute COVID-19, few studies have examined PASC over a longer follow-up duration or accounted for rates of symptoms and diagnoses before COVID-19 infection, and included those not actively seeking treatment for PASC. To determine what symptoms and diagnoses are occurring at higher rates after acute COVID-19 infection from a more inclusive sample, we extracted electronic hospital records (EHR) data from 13,033 adults with previously known diagnoses and symptoms. Methods: The sample was comprised of patients who had a positive PCR test for SARS-CoV-2 between March 1, 2020, and December 31, 2020, and follow-up was conducted through November 29, 2021. All patients in the sample had medical appointments ≥4 weeks before and ≥4 weeks after their positive PCR test. At these appointments, all ICD-10 codes recorded in the EHR were classified into 21 categories based on the literature and expert review. Conditional logistic regression models were used to quantify the odds of these symptoms and diagnostic categories following COVID-19 infection relative to visits occurring before infection. The sample was comprised of 28.0% adults over 65 and was 57.0% female. After the positive PCR test, the most recorded diagnoses and symptoms were dyspnea and respiratory failure, myositis, musculoskeletal pain/stiffness, anxiety, and depression. Results: Results from regression analyses showed increased odds of diagnosis for 15 of the 21 categories following positive PCR. Relative to pre-COVID, the diagnoses and symptoms with the greatest odds after a positive PCR test were loss of smell or taste [OR (95% CI) = 6.20 (3.18–12.09)], pulmonary fibrosis [3.50 (1.59–7.68)], and dyspnea/respiratory failure [2.14 (1.92–2.40)]. Stratification of these analyses by age, gender, race, and ethnicity showed similar results. Conclusion: The increased symptoms and diagnoses detected in the current study match prior analyses of PASC diagnosis and treatment-seeking patients. The current research expands upon the literature by showing that these symptoms are more frequently detected following acute COVID-19 than before COVID-19. Further, our analyses provide a broad snapshot of the population as we were able to describe PASC among all patients who tested positive for COVID-19. [ABSTRACT FROM AUTHOR]

Background: Long COVID is a devastating, long-term, debilitating illness which disproportionately affects healthcare workers, due to the nature of their work. There is currently limited evidence specific to healthcare workers about the experience of living with Long COVID, or its prevalence, pattern of recovery or impact on healthcare. Objective: Our objective was to assess the effects of Long COVID among healthcare workers and its impact on health status, working lives, personal circumstances, and use of health service resources. Methods: We conducted a systematic rapid review according to current methodological standards and reported it in adherence to the PRISMA 2020 and ENTREQ statements. Results: We searched relevant electronic databases and identified 3770 articles of which two studies providing qualitative evidence and 28 survey studies providing quantitative evidence were eligible. Thematic analysis of the two qualitative studies identified five themes: uncertainty about symptoms, difficulty accessing services, importance of being listened to and supported, patient versus professional identity and suggestions to improve communication and services for people with Long COVID. Common long-term symptoms in the survey studies included fatigue, headache, loss of taste and/or smell, breathlessness, dyspnoea, difficulty concentrating, depression and anxiety. Conclusion: Healthcare workers struggled with their dual identity (patient/doctor) and felt dismissed or not taken seriously by their doctors. Our findings are in line with those in the literature showing that there are barriers to healthcare professionals accessing healthcare and highlighting the challenges of receiving care due to their professional role. A more representative approach in Long COVID research is needed to reflect the diverse nature of healthcare staff and their occupations. This rapid review was conducted using robust methods with the codicil that the pace of research into Long COVID may mean relevant evidence was not identified. [ABSTRACT FROM AUTHOR]

While measures to detect psychophysical olfactory ability are a crucial part of clinicians' assessment of potential olfactory loss, it gives no indication of how olfaction is experienced by the patient and these different aspects often deviate substantially. To ensure quality and reproducibility of subjectively reported olfactory experience and significance, the Importance of Olfaction Questionnaire (IO-Q) was introduced around a decade ago, and while initial validations have produced promising results, important aspects remain nearly unexamined. For example, the test-retest reliability has rarely been examined and the difference of online versus pen-and-paper administration remains unexplored. Here, we translated IO-Q to Danish and examined its validity, test-retest reliability and mode of administration. A cohort of 179 younger, Danish participants with a high level of English proficiency took the test twice with varying time in-between. The first test was taken digitally and in English, while the second was taken using pen-and-paper and in Danish. The distribution of scores and the relationship between the IO-Q and subscale scores were nearly identical between tests, indicating little to no influence of language/test modality in the sampled population. The internal consistency was comparable to previously published results. Likewise, an acceptable test-retest reliability was observed for the full IO-Q and slightly lower for subscales. No significant effect of time was found across several weeks. In conclusion, the IO-Q performed satisfactorily in all examinations and could therefore serve as a valuable clinical measure of subjective olfactory experience, and its Danish translation shows highly similar characteristics to the original, English version. [ABSTRACT FROM AUTHOR]

Objective olfactory function can be assessed using validated olfactory tests like the Sniffin' Sticks Test (SST). However, their extensive nature makes them less suitable for clinical practice. To address this, shorter olfactory tests like the screenings Sniffin' Sticks Test (SST-12) can be used for screening purposes and reduce testing time. The SST-12 serves as a diagnostic tool for screening olfaction in cases unrelated to COVID-19. However, these screening tests are uncertain regarding their accuracy in detecting olfactory dysfunction in patients with COVID-19 as the plausible cause. We aim to determine the diagnostic accuracy of the SST-12 in adults with post-COVID-19 olfactory dysfunction. We performed a diagnostic accuracy study with data from 113 consecutive COVID-19 diagnosed patients who experienced objectified smell loss ever since. At approximately 6 months after their diagnosis, all participants underwent the SST (reference standard), part of the SST was the SST-12 (index test). Diagnostic accuracy of the SST-12 is measured as negative predictive value (NPV), positive predictive value (PPV), sensitivity, and specificity. The SST-12 detected smell loss in 85 patients among 91 patients with smell loss and ruled out smell loss in 15 patients among the 22 patients without smell loss based on the reference standard. Making sensitivity 93.4% (CI 0.87–0.97), and specificity 68.2% (CI 0.48–0.85). Out of the 92 patients with a positive test result on SST-12, 85 patients had indeed smell loss (PPV 92.4% CI 0.86–0.97), and out of the 21 patients with a negative test result, 15 patients had no smell loss regarding the reference standard (NPV 71.4% CI 0.50–0.88). The findings suggest that the SST-12 holds promise as a useful tool for identifying individuals with smell loss, also in individuals with COVID-19 as cause, but it is important to have a good understanding of the interpretation of the results of the SST-12 when considering its implementation in clinical practice. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the relationship between Temporomandibular disorder (TMD) and associated comorbidities in groups matched according to age and sex. Methods: Using data from the cross-sectional fifth Korea National Health and Nutrition Examination Survey (KNHANES). Of the 25,534 eligible KNHANES, 17,762 adults aged ≥19 years who responded to survey questionnaire on TMD and comorbidities. Subjects were classified into eight groups according to age and sex. Logistic regression analyses were performed to evaluate the association between TMD and comorbidities according to age and sex. Results: Of the enrolled participants, 2,107 (11.86%) complained of ≥1 TMD symptoms. In all groups, odds ratios (ORs) for prevalence of TMD were >1 in those with tinnitus. Rhinitis was closely associated with TMD in 6 groups. ORs for TMD with comorbidities according to age and sex were as follows: hypertension, men aged 50–64 years (OR 0.62; CI 0.41–0.94); ischemic heart disease, men aged 35–49 years (4.38; 1.54–12.47); osteoarthritis, women aged 50–64 years (1.38; 1.03–1.86); diabetes mellitus, men aged 35–49 years (0.21; 0.05–0.88); depression, men aged 50–64 years (1.68; 1.00–2.83), women aged 35–49 years (1.39; 1.05–1.85) and women aged 65–80 years (2.01; 1.46–2.77); migraine, men aged 50–64 years (1.60; 1.14–2.25), women aged d35-49 years (1.44; 1.14–1.81) and women aged 35–49 years (1.43; 1.07–1.90); cold hypersensitivity in the hands and feet, men aged 19–34 years (1.64; 1.05–2.58), men aged 35–49 years (1.68; 1.04–2.70), men aged 65–80 years (1.74; 1.09–2.75) and women aged 35–49 years (1.45; 1.15–1.84); olfaction disorder, men aged 50–64 years (2.49; 1.39–4.43); voice disorder, men aged 50–64 years (2.25; 1.28–3.96) and women aged 65–80 years (1.69; 1.09–2.63) Conclusions: This study confirmed that the types and effects of comorbidities related to prevalence of TMD may differ according to the patient's age and sex and this result will increase the predictability of the onset of TMD. [ABSTRACT FROM AUTHOR]

Defining perceptual similarity metrics for odorant comparisons is crucial to understanding the mechanism of olfactory perception. Current methods in olfaction rely on molecular physicochemical features or discrete verbal descriptors (floral, burnt, etc.) to approximate perceptual (dis)similarity between odorants. However, structural or verbal descriptors alone are limited in modeling complex nuances of odor perception. While structural features inadequately characterize odor perception, language-based discrete descriptors lack the granularity needed to model a continuous perception space. We introduce data-driven approaches to perceptual metrics learning (PMeL) based on two key insights: a) by combining physicochemical features with the user's perceptual feedback, we can leverage both structural and perceptual attributes of odors to define dissimilarity, and b) instead of discrete labels, user's perceptual feedback can be gathered as relative similarity comparisons, such as "Does molecule-A smell more like molecule-B, or molecule-C?" These triplet comparisons are easier even for non-experts users and offer a more effective representation of the continuous perception space. Experimental results on several defined tasks show the effectiveness of our approach in evaluating perceptual dissimilarity between odorants. Finally, we investigate how closely our model, trained on non-expert feedback, aligns with the expert's similarity judgments. Our effort aims to reduce reliance on expert annotations. [ABSTRACT FROM AUTHOR]

This study addresses the paucity of research concerning the subjective experiences of those affected by anosmia. In the study, we interviewed individuals(n = 11) recruited via the charity (Fifth Sense) and used Interpretative Phenomenological Analysis (IPA) to analyse the data. Findings revealed three main themes and seven sub themes. The main themes are Living with Anosmia; Remembrance of things old and new and Resilience. The study reveals the process of becoming aware of being anosmic and the relationships with others in this process including potentially unhelpful minimisations of the impact by professionals. In addition to a sense of isolation and insecurity, living with anosmia for some participants brought with it an identification of being 'anosmic' and feeling part of a community. This was in contrast to a general lack of public knowledge and understanding of anosmia. The findings of the study demonstrated the importance of smell to time, place and relationship and the recalling of smells as bringing a sense of connectivity to loved ones, of times past and also a sense of loss of ability. Participants also described the ways in which they coped and adapted to a life with anosmia and focused on positive aspects of life. These findings provide a rich qualitative account of the experience of anosmia. The findings point towards future research which could inform us about the lives of those who are anosmic and currently unaware and of those recently diagnosed, which will create a richer understanding of the experiences of anosmia. [ABSTRACT FROM AUTHOR]

Recent research has attempted to predict our perception of odorants using Machine Learning models. The featurization of the olfactory stimuli usually represents the odorants using molecular structure parameters, molecular fingerprints, mass spectra, or e-nose signals. However, the impact of the choice of featurization on predictive performance remains poorly reported in direct comparative studies. This paper experiments with different sensory features for several olfactory perception tasks. We investigate the multilabel classification of aroma molecules in odor descriptors. We investigate single-label classification not only in fine-grained odor descriptors ('orange', 'waxy', etc.), but also in odor descriptor groups. We created a database of odor vectors for 114 aroma molecules to conduct our experiments using a QCM (Quartz Crystal Microbalance) type smell sensor module (Aroma Coder®V2 Set). We compare these smell features with different baseline features to evaluate the cluster composition, considering the frequencies of the top odor descriptors carried by the aroma molecules. Experimental results suggest a statistically significant better performance of the QCM type smell sensor module compared with other baseline features with F1 evaluation metric. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid Smell Agent Symbiosis Organism Search Algorithm (SASOS) for optimal control of autonomous microgrids. In microgrid operation, a single optimization algorithm often lacks the required balance between accuracy and speed to control power system parameters such as frequency and voltage effectively. The hybrid algorithm reduces the imbalance between exploitation and exploration and increases the effectiveness of control optimization in microgrids. To achieve this, various energy resource models were coordinated into a single model for optimal energy generation and distribution to loads. The optimization problem was formulated based on the network power flow and the discrete-time sampling of the constrained control parameters. The development of SASOS comprises components of Symbiotic Organism Search (SOS) and Smell Agent Optimization (SAO) codified in an optimization loop. Twenty-four standard test function benchmarks were used to evaluate the performance of the algorithm developed. The experimental analysis revealed that SASOS obtained 58.82% of the Desired Convergence Goal (DCG) in 17 of the benchmark functions. SASOS was implemented in the Microgrid Central Controller (MCC) and benchmarked alongside standard SOS and SAO optimization control strategies. The MATLAB/Simulink simulation results of the microgrid load disturbance rejection showed the viability of SASOS with an improved reduction in Total Harmonic Distortion (THD) of 19.76%, compared to the SOS, SAO, and MCC methods that have a THD reduction of 15.60%, 12.74%, and 6.04%, respectively, over the THD benchmark. Based on the results obtained, it can be concluded that SASOS demonstrates superior performance compared to other methods. This finding suggests that SASOS is a promising solution for enhancing the control system of autonomous microgrids. It was also shown to apply to other sectors of engineering optimization. [ABSTRACT FROM AUTHOR]

Conservation of endangered fishes commonly includes captive breeding, applied research, and management. Since 1996, a captive breeding program has existed for the federally threatened and California endangered Delta Smelt Hypomesus transpacificus, an osmerid fish endemic to the upper San Francisco Estuary. Although this program serves as a captive refuge population, with experimental releases being initiated to supplement the wild population, it was uncertain how individuals would survive, feed, and maintain condition outside hatchery conditions. We evaluated this and the effects of three enclosure designs (41% open, 63% open, and 63% open with partial outer mesh wrap) on growth, survival, and feeding efficacy of cultured Delta Smelt at two locations (Sacramento River near Rio Vista, CA and in Sacramento River Deepwater Ship Channel) in the wild. Enclosures exposed fish to semi-natural conditions (ambient environmental fluctuations and wild food resources) but prevented escape and predation. After four weeks, survival was high for all enclosure types (94–100%) at both locations. The change in condition and weight was variable between sites, increasing at the first location but decreasing at the second location. Gut content analysis showed that fish consumed wild zooplankton that came into the enclosures. Cumulatively, results show that captive-reared Delta Smelt can survive and forage successfully when housed in enclosures under semi-natural conditions in the wild. When comparing enclosure types, we observed no significant difference in fish weight changes (p = 0.58–0.81 across sites). The success of housing captive-reared Delta Smelt in enclosures in the wild provides preliminary evidence that these fish may be suitable to supplement the wild population in the San Francisco Estuary. Furthermore, these enclosures are a new tool to test the efficacy of habitat management actions or to acclimate fish to wild conditions as a soft release strategy for recently initiated supplementation efforts. [ABSTRACT FROM AUTHOR]

MHC genes play a fundamental role in immune recognition of pathogens and parasites. Therefore, females may increase offspring heterozygosity and genetic diversity by selecting males with genetically compatible or heterozygous MHC. In birds, several studies suggest that MHC genes play a role in mate choice, and recent evidence suggests that olfaction may play a role in the MHC-II discrimination. However, whether olfaction is involved in MHC-I discrimination in birds remains unknown. Previous studies indicate that house sparrow females with low allelic diversity prefer males with higher diversity in MHC-I alleles. Here, we directly explored whether female and male house sparrows (Passer domesticus) could estimate by scent MHC-I diversity and/or dissimilarity of potential partners. Our results show that neither females nor males exhibit a preference related to MHC-I diversity or dissimilarity of potential partners, suggesting that MHC-I is not detected through olfaction. Further studies are needed to understand the mechanisms responsible for mate discrimination based on MHC-I in birds. [ABSTRACT FROM AUTHOR]

A quantitative monitoring system for fractional exhaled nitric oxide (FENO) in homes is very important for the control of respiratory diseases such as asthma. To this end, this paper proposes a small bionic sensing system for NO detection in an electronic nose based on analysis of the structure of the canine olfactory system and the airflow pattern in the nasal cavity. The proposed system detected NO at different FENO concentration levels with different bionic sensing systems in the electronic nose, and analyzed the data comparatively. Combined with a backpropagation neural network algorithm, the bionic canine sensing system improved the recognition rate for FENO detection by up to 98.1%. Moreover, electronic noses with a canine bionic sensing system can improve the performance of trace gas detection. [ABSTRACT FROM AUTHOR]

Objective: Smell and taste alteration are closely linked to infection with SARS-CoV-2 and may be associated with a more indolent disease course. Serologic response rates among individuals with mild disease remains limited. We sought to identify whether chemosensory changes associated with COVID-19 were predictive of a serologic response. Study design: Cross-sectional study. Methods: The sample consisted of 306 adults (≥18 years old) volunteering for convalescent plasma donation following perceived COVID-19 illness from April-June 2020. Documentation of COVID-19 PCR status, clinical symptoms at time of illness, and treatment course occurred at the time of serologic analysis, where we assessed chemosensory function using patient-perceived deficits. We implemented previously validated ELISA screening to determine serologic status regarding anti-Spike immunoglobulins. Statistical analysis using stepwise logistic models were employed to identify predictive factors of serologic response. Results: Of 306 patients undergoing serologic and chemosensory evaluation, 196 (64.1%) and 195 (63.7%) reported subjective olfactory and taste dysfunction, respectively, during the first two weeks of COVID-19 infection. In unadjusted models, the odds of developing suprathreshold IgG antibody titers were 1.98 times higher among those who reported altered smell (95% CI 1.14–3.42, p = 0.014) and 2.02 times higher among those with altered taste (95% CI 1.17–3.48, p = 0.011) compared to those with normal smell and taste. Multivariable logistic models adjusting for sex, age, race/ethnicity, symptom duration, smoking status and comorbidities index demonstrated that altered smell and taste remained significant predictors of positive anti-spike IgG response (smell OR = 1.90, 95% CI 1.05–3.44, p = 0.033; taste OR = 2.01, 95% CI = 1.12–3.61, p = 0.019). Conclusion: Subjective chemosensory dysfunction, as self-reported smell or taste deficiency, is highly predictive of serologic response following SARS-CoV-2 infection. This information may be useful for patient counseling. Additional longitudinal research should be performed to better understand the onset and duration of the serologic response in these patients. [ABSTRACT FROM AUTHOR]

Background: Little is known about olfactory changes in pediatric COVID-19. It is possible that children under-report chemosensory changes on questionnaires, similar to reports in adults. Here, we aim to describe COVID-19-related olfactory dysfunction in outpatient children. We hypothesized that children with COVID-19 will demonstrate abnormal olfaction on smell-identification testing at a higher rate than children with negative COVID-19 testing. Methods: A prospective cross-sectional study was undertaken from June 2020—June 2021 at a tertiary care pediatric hospital. A consecutive sample of 205 outpatients aged 5–21 years undergoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) PCR testing were approached for this study. Patients with prior olfactory dysfunction were excluded. Participants were given a standard COVID-19 symptom questionnaire, a Smell Identification Test (SIT) and home-odorant-based testing within 2 weeks of COVID-19 testing. Prior to study enrollment, power calculation estimated 42 patients to determine difference in rates of SIT results between groups. Data were summarized with descriptive statistics. Results: Fifty-one patients underwent smell identification testing (23 positive (45%) and 28 negative (55%) for COVID-19; mean age 12.7 years; 60% female). 92% of all patients denied subjective change in their sense of smell or taste but only 58.8% were normosmic on testing. There was no difference in screening questionnaires or SIT scores between COVID-19 positive and negative groups. Conclusions: Unlike adults, there was no statistical difference in olfactory function between outpatient COVID-19 positive and negative children. Our findings suggest a discrepancy between objective and patient-reported olfactory function in pediatric patients, and poor performance of current screening protocols at detecting pediatric COVID-19. [ABSTRACT FROM AUTHOR]

The quality of the dietary habits of older adults is important for increasing healthy life expectancy. As with other physical senses, the senses of taste and olfaction change with age. In contrast to physical sensations that can be visibly compared with those of other people, taste and olfaction are personal sensations, making it challenging to infer associated changes. This study investigated the characteristics of taste and olfaction in healthy older adults and compared them with those of young adults. In the taste assessment, threshold values were measured using the whole-mouth method with a diagnostic assay kit (Tastedisc). The olfactory assessment measured the overall identification ability using a card-type olfactory identification test kit (Open Essence). Additionally, participants' subjective health awareness was measured using a visual analog scale. The taste and olfactory assessments results showed that the older group had lower overall sensory sensitivity than the young group, and that there was no correlation between taste and olfactory sensitivity in the older group, while a trend was observed in the young group. Moreover, there was no significant difference between the two groups regarding subjective health awareness, indicating that participants in our research considered themselves healthy regardless of age. This suggests that the subjective health awareness of older people in the health promotion class is somehow independent from their sensory ability. [ABSTRACT FROM AUTHOR]

Background: COVID-19 can cause some individuals to experience chronic symptoms. Rates and predictors of chronic COVID-19 symptoms are not fully elucidated. Objective: To examine occurrence and patterns of post-acute sequelae of SARS-CoV2 infection (PASC) symptomatology and their relationship with demographics, acute COVID-19 symptoms and anti-SARS-CoV-2 IgG antibody responses. Methods: A multi-stage observational study was performed of adults (≥18 years) from 5 US states. Participants completed two rounds of electronic surveys (May-July 2020; April-May 2021) and underwent testing to anti-SARS-CoV-2 nucleocapsid protein IgG antibody testing. Latent Class Analysis was used to identify clusters of chronic COVID-19 symptoms. Results: Overall, 390 adults (median [25%ile, 75%ile] age: 42 [31, 54] years) with positive SARS-CoV-2 antibodies completed the follow-up survey; 92 (24.7%) had ≥1 chronic COVID-19 symptom, with 11-month median duration of persistent symptoms (range: 1–12 months). The most common chronic COVID-19 symptoms were fatigue (11.3%), change in smell (9.5%) or taste (5.6%), muscle or joint aches (5.4%) and weakness (4.6%). There were significantly higher proportions of ≥1 persistent COVID-19 symptom (31.5% vs. 18.6%; Chi-square, P = 0.004), and particularly fatigue (15.8% vs. 7.3%, P = 0.008) and headaches (5.4% vs. 1.0%, P = 0.011) in females compared to males. Chronic COVID-19 symptoms were also increased in individuals with ≥6 acute COVID-19 symptoms, Latent class analysis revealed 4 classes of symptoms. Latent class-1 (change of smell and taste) was associated with lower anti-SARS-CoV-2 antibody levels; class-2 and 3 (multiple chronic symptoms) were associated with higher anti-SARS-CoV-2 antibody levels and more severe acute COVID-19 infection. Limitations: Ambulatory cohort with less severe acute disease. Conclusion: Individuals with SARS-CoV-2 infection commonly experience chronic symptoms, most commonly fatigue, changes in smell or taste and muscle/joint aches. Female sex, severity of acute COVID-19 infection, and higher anti-SARS-CoV-2 IgG levels were associated with the highest risk of having chronic COVID-19 symptoms. [ABSTRACT FROM AUTHOR]

Surf smelt (Hypomesus pretiosus) are ecologically critical forage fish in the North Pacific ecosystem. As obligate beach spawners, surf smelt embryos are exposed to wide-ranging marine and terrestrial environmental conditions. Despite this fact, very few studies have assessed surf smelt tolerance to climate stressors. The purpose of this study was to examine the interactive effects of climate co-stressors ocean warming and acidification on the energy demands of embryonic and larval surf smelt. Surf smelt embryos and larvae were collected from spawning beaches and placed into treatment basins under three temperature treatments (13°C, 15°C, and 18°C) and two pCO2 treatments (i.e. ocean acidification) of approximately 900 and 1900 μatm. Increased temperature significantly decreased yolk size in surf smelt embryos and larvae. Embryo yolk sacs in high temperature treatments were on average 7.3% smaller than embryo yolk sacs from ambient temperature water. Larval yolk and oil globules mirrored this trend. Larval yolk sacs in the high temperature treatment were 45.8% smaller and oil globules 31.9% smaller compared to larvae in ambient temperature. There was also a significant positive effect of acidification on embryo yolk size, indicating embryos used less maternally-provisioned energy under acidification scenarios. There was no significant effect of either temperature or acidification on embryo heartrates. These results indicate that near-future climate change scenarios may impact the energy demands of developing surf smelt, leading to potential effects on surf smelt fitness and contributing to variability in adult recruitment. [ABSTRACT FROM AUTHOR]

Background: Throughout the COVID-19 pandemic, testing individuals remains a key action. One approach to rapid testing is to consider the olfactory capacities of trained detection dogs. Methods: Prospective cohort study in two community COVID-19 screening centers. Two nasopharyngeal swabs (NPS), one saliva and one sweat samples were simultaneously collected. The dog handlers (and the dogs...) were blinded with regards to the Covid status. The diagnostic accuracy of non-invasive detection of SARS-CoV-2 infection by canine olfaction was assessed as compared to nasopharyngeal RT-PCR as the reference standard, saliva RT-PCR and nasopharyngeal antigen testing. Results: 335 ambulatory adults (143 symptomatic and 192 asymptomatic) were included. Overall, 109/335 participants tested positive on nasopharyngeal RT-PCR either in symptomatic (78/143) or in asymptomatic participants (31/192). The overall sensitivity of canine detection was 97% (95% CI, 92 to 99) and even reached 100% (95% CI, 89 to 100) in asymptomatic individuals compared to NPS RT-PCR. The specificity was 91% (95% CI, 72 to 91), reaching 94% (95% CI, 90 to 97) for asymptomatic individuals. The sensitivity of canine detection was higher than that of nasopharyngeal antigen testing (97% CI: 91 to 99 versus 84% CI: 74 to 90, p = 0.006), but the specificity was lower (90% CI: 84 to 95 versus 97% CI: 93 to 99, p = 0.016). Conclusions: Non-invasive detection of SARS-CoV-2 infection by canine olfaction could be one alternative to NPS RT-PCR when it is necessary to obtain a result very quickly according to the same indications as antigenic tests in the context of mass screening. [ABSTRACT FROM AUTHOR]

L-Lactate (LL) is an essential cellular metabolite which can be used to generate energy. In addition, accumulating evidence suggests that LL is used for inter-cellular signalling. Some LL-sensitive receptors have been identified but we recently proposed that there may be yet another unknown G-protein coupled receptor (GPCR) sensitive to LL in the brain. Olfactory receptors (ORs) represent the largest family of GPCRs and some of them are expressed outside the olfactory system, including brain, making them interesting candidates for non-olfactory LL signalling. One of the "ectopically" expressed ORs, Olfr78 in mice (Olr59 in rats and OR51E2 in humans), reportedly can be activated by LL. This implies that both rodents and humans should be able to detect the LL odour. Surprisingly, this has never been demonstrated. Here we show that mice can detect the odour of LL in odour detection and habituation-dishabituation tasks, and discriminate it from peppermint and vanilla odours. Behaviour of the Olfr78 null mice and wildtype mice in odour detection task was not different, indicating that rodents are equipped with more than one LL-sensitive OR. Rats were also able to use the smell of LL as a cue in an odour-reward associative learning task. When presented to humans, more than 90% of participants detected a smell of LL in solution. Interestingly, LL was perceived differently than acetate or propionate-LL was preferentially reported as a pleasant sweet scent while acetate and propionate were perceived as repulsive sour/acid smells. Subjective perception of LL smell was different in men and women. Taken together, our data demonstrate that both rodents and humans are able to detect the odour of LL. Moreover, in mice, LL perception is not purely mediated by Olfr78. Discovery of further LL-sensitive OR might shed the light on their contribution to LL signalling in the body.

Background: The importance and prevalence of olfactory dysfunction is recently gaining attention in patients with multiple sclerosis (MS) as a result of their chronic inflammatory disease, yet different prevalence rates are reported for it. Therefore, we have designed this systematic review to estimate the pooled prevalence of olfactory dysfunction in patients with MS. To our knowledge, this is the first systematic review and meta-analysis on the prevalence of olfactory dysfunction in MS patients. Methods: We searched PubMed, Scopus, EMBASE, Web of Science, ProQuest, and gray literature including references from the identified studies, review studies, and conference abstracts which were published up to January 2021. Articles that were relevant to our topic and could provide information regarding the prevalence of olfactory dysfunction, or the scores of smell threshold, discrimination, or identification (TDI) among MS patients and healthy individuals were included. The pooled prevalence was calculated using a random-effects model and a funnel plot and Egger's regression test were used to see publication bias. Results: The literature search found 1630 articles. After eliminating duplicates, 897 articles remained. Two conference abstracts were included for final analysis. A total of 1099 MS cases and 299 MS patients with olfactory dysfunction were included in the analysis. The pooled prevalence of olfactory dysfunction in the included studies was 27.2%. Also, the overall TDI score in MS patients was lower than that in the control group, and the level of Threshold, Discrimination, and Identification per se were lower in MS compared with control respectively. Conclusion: The results of this systematic review show that the prevalence of olfactory dysfunction in MS patients is high and more attention needs to be drawn to this aspect of MS. [ABSTRACT FROM AUTHOR]

Background Altered sense of smell is a commonly reported COVID-19 symptom. The performance of smell testing to identify SARS-CoV-2 infection status is unknown. We measured the ability of formal smell testing to identify SARS-CoV-2 infection and compared its performance with symptom screening. Methods A convenience sample of emergency department patients with COVID-19 symptom screening participated in smell testing using an eight odor Pocket Smell Test (PST). Participants received a SARS-CoV-2 viral PCR test after smell testing and completed a health conditions survey. Descriptive analysis and receiver operating characteristic (ROC) curve models compared the accuracy of smell testing versus symptom screening in identifying SARS-CoV-2 infection. Results Two hundred and ninety-five patients completed smell testing and 87 (29.5%) had a positive SARS-CoV-2 PCR test. Twenty-eight of the SARS-CoV-2 positive patients (32.2%) and 49 of the SARS-CoV-2 negative patients (23.6%) reported at least one of seven screening symptoms (OR = 1.54, P = 0.13). SARS-CoV-2 positive patients were more likely to have hyposmia (?5 correctly identified odors) than SARS-CoV-2 negative patients (56.1% vs. 19.3%, OR = 5.36, P<0.001). Hyposmia was 52.9% (95% CI 41.9%-63.7%) sensitive and 82.7% (95% CI 76.9%-87.6%) specific for SARS-CoV-2 infection. Presence of ?1 screening symptom was 32.2% (95% CI 22.6%-43.1%) sensitive and 76.4% (70.1%-82.0%) specific for SARS-CoV-2 infection. The ROC curve for smell testing had an area under the curve (AUC) of 0.74 (95% CI 0.67-0.80). The ROC curve for symptom screening had lower discriminatory accuracy for SARS-CoV-2 infection (AUC = 0.55, 95% CI 0.49-0.61, P<0.001) than the smell testing ROC curve. Conclusion Smell testing was superior to symptom screening for identifying SARS-CoV-2 infection in our study. [ABSTRACT FROM AUTHOR]

Virtual reality (VR) headsets provide immersive audio-visual experiences for users, but usually neglect to provide olfactory cues that can provide additional information about our environment in the real world. This paper examines whether the introduction of smells into the VR environment enhances users' experience, including their sense of presence through collection of both psychological and physiological measures. Using precise odour administration with an olfactometer, study participants were exposed to smells while they were immersed in the popular PlayStation VR game "Resident Evil 7". A within-subject study design was undertaken where participants (n = 22) walked-through the same VR environment twice, with or without the introduction of associated congruent odour stimuli. Directly after each gameplay, participants completed a questionnaire to determine their sense of presence from the overall gameplay and their sense of immersion in each of the virtual scenes. Additionally, physiological measurements (heart rate, body temperature and skin electrodermal activity) were collected from participants (n = 11) for each gameplay. The results showed the addition of odours significantly increased participants' sense of spatial presence in the VR environment compared to VR with no odour. Participants also rated the realism of VR experience with odour higher compared to no odour, however odour addition did not result in change in emotional state of participants (arousal, pleasure, dominance). Further, the participants' physiological responses were impacted by the addition of odour. Odour mediated physiological changes were dependent on whether the VR environment was novel, as the effect of odour on physiological response was lost when participants experienced the aroma on the second gameplay. Overall, the results indicate the addition of odours to a VR environment had a significant effect on both the psychological and physiological experience showing the addition of smell enhanced the VR environment. The incorporation of odours to VR environments presents an opportunity to create a more immersive experience to increase a person's presence within a VR environment. In addition to gaming, the results have broader applications for virtual training environments and virtual reality exposure therapy. [ABSTRACT FROM AUTHOR]

Olfactory and gustatory disorders are prominent symptoms of acute COVID-19. Although both senses recover in many patients within weeks to months, persistency has been described in up to 60%. However up to now most reports on the course of chemosensitive disorders after COVID-19 are not based on psychophysical testing but only on subjective patients' ratings. In this study we assessed both olfaction and gustation using psychophysical tests eight months after COVID-19. Validated psychophysical testing revealed hyposmia in 18% and hypogeusia in even 32% of 303 included patients. This shows that olfactory and especially gustatory disorders have to be seen as important chronic symptoms post-COVID-19. The high prevalence of gustatory dysfunction indicates that gustatory function does not recover or might even deteriorate in the months following the acute infection. [ABSTRACT FROM AUTHOR]

Understanding reproductive biology and performance of fish is essential to formulate effective conservation and management programs. Here, we studied reproductive strategies of female Delta Smelt Hypomesus transpacificus, an endangered fish species in the State of California, the United States, focusing on (1) better understanding their distribution pattern during the winter and spring spawning season at very fine scale to predict their possible spawning grounds and (2) assessing impacts of a recent, severe drought on their reproductive performance. We formulated our hypotheses as follows; (1) female Delta Smelt migrate to particular locations for spawning so that mature females can be frequently found in those locations throughout the spawning season and (2) reproductive performance of individual female fish declined during the drought. To test the first hypotheses, we analyzed relationships between water quality parameters and maturity/distribution pattern of Delta Smelt. Salinity better explained the distribution pattern of Delta Smelt at subadult and adult stages compared with water temperature or turbidity. Although there are some freshwater locations where mature Delta Smelt can frequently be found during the spawning season, Delta Smelt at the final maturation stage (Stage 5: hydration) and post spawners appeared to be widespread in the area where salinity was below 1.0 during the spawning season. Therefore, Delta Smelt could theoretically spawn in any freshwater locations, with more specific spawning requirements in the wild (e.g., substrate type and depth) still unknown. Delta Smelt, which experienced dry and critically dry conditions (the 2013 and 2014 year-classes), showed smaller oocytes, and lower clutch size and gonadosomatic index compared with the fish caught in a wet year (2011 year-class) at the late vitellogenic stage (Stage 4 Late), suggesting reproductive performance was negatively affected by environmental conditions during the drought. [ABSTRACT FROM AUTHOR]

How animals navigate the constantly moving and visually uniform pelagic realm, often along straight paths between distant sites, is an enduring mystery. The mechanisms enabling pelagic navigation in cartilaginous fishes are particularly understudied. We used shoreward navigation by leopard sharks (Triakis semifasciata) as a model system to test whether olfaction contributes to pelagic navigation. Leopard sharks were captured alongshore, transported 9 km offshore, released, and acoustically tracked for approximately 4 h each until the transmitter released. Eleven sharks were rendered anosmic (nares occluded with cotton wool soaked in petroleum jelly); fifteen were sham controls. Mean swimming depth was 28.7 m. On average, tracks of control sharks ended 62.6% closer to shore, following relatively straight paths that were significantly directed over spatial scales exceeding 1600 m. In contrast, tracks of anosmic sharks ended 37.2% closer to shore, following significantly more tortuous paths that approximated correlated random walks. These results held after swimming paths were adjusted for current drift. This is the first study to demonstrate experimentally that olfaction contributes to pelagic navigation in sharks, likely mediated by chemical gradients as has been hypothesized for birds. Given the similarities between the fluid three-dimensional chemical atmosphere and ocean, further research comparing swimming and flying animals may lead to a unifying paradigm explaining their extraordinary navigational abilities.

Extracts of the exuviae (cast skins) of nymphal bed bugs (Cimex lectularius) were analyzed for volatile compounds that might contribute to arrestment of adult bed bugs. Four volatile aldehydes, (E)-2-hexenal, 4-oxo-(E)-2-hexenal, (E)-2-octenal, and 4-oxo-(E)-2-octenal were consistently detected in the headspace of freshly shed exuviae regardless of the developmental stages from which the exuviae were obtained. Quantification of the aldehydes in the solvent extracts of homogenized fresh, 45- or 99-d aged 5th instar exuviae indicated that the aldehydes are present in the exuviae and dissipate over time, through evaporation or degradation. Microscopic observation of the fifth instar exuviae indicated that the dorsal abdominal glands on the exuviae maintained their pocket-like structures with gland reservoirs, within which the aldehydes might be retained. Two-choice olfactometer studies with the volatiles from exuviae or a synthetic blend mimicking the volatiles indicated that adult bed bugs tend to settle close to sources of the aldehydes. Our results imply that the presence and accumulation of bed bug exuviae and the aldehydes volatilizing from the exuviae might mediate bed bugs' interaction with their microhabitats.

Background: In older adults, kidney function declines with age. People with advanced kidney diseases may have poor olfaction. However, it is unclear whether poor olfaction is a marker for declining renal function or future risk of chronic kidney disease (CKD). We therefore investigated olfaction in relation to kidney function and risk of CKD. Methods: These secondary data analyses were limited to participants of the year 3 clinical visit of the Health Aging and Body Composition Study. The analytic sample size varied between 1427 to 2531, depending on participant eligibility and data availability for each analysis. Olfaction was tested using the Brief Smell Identification Test (B-SIT), defined as anosmia (score≤6), hyposmia (7–8), moderate (9–10), and good function (10–11) at baseline. We estimated glomerular filter rate (eGFR) at baseline and seven years later using the CKD-EPI creatinine-cystatin C equation, and defined incident CKD as eGFR<60 ml/min/1.73m2 and eGFR decline ≥1 ml/min/1.73m2/year. Further, we identified CKD hospitalization events from hospitalization and death records. We used inverse probability weighting and weighted multivariable regressions to account for censoring in the prospective analyses and used absolute risk regression to account for competing risk of death. Results: At baseline, compared to participants with good olfaction, the multivariable-adjusted mean eGFR was 3.00 ml/min/1.73m2 lower (95% confidence interval (CI): -5.25, -0.75) for those with anosmia and 1.87 lower (95% CI: -3.94, 0.21) for those with hyposmia with a P for linear trend < 0.001. Those with anosmia at baseline was had a significantly lower eGFR seven years later (-5.31, 95% CI: -8.58, -2.04, P for trend = 0.002), but the association was attenuated after further accounting for baseline eGFR (-2.37, 95%CI: -4.91, 0.16, P for linear trend = 0.147). Olfactory function was not associated with incident CKD or CKD hospitalization. Conclusion: In older adults > age 70 years, poor olfaction is associated with lower kidney function, but not future CKD risk. These associations should be further investigated in relatively younger population. [ABSTRACT FROM AUTHOR]

Introduction: Most COVID-19 symptoms are non-specific and also common in other respiratory infections. We aimed to assess which symptoms are most predictive of a positive test for SARS-CoV-2 in symptomatic people of the general population who were tested. Methods: We used anonymised data of all SARS-CoV-2 test results from the Public Health Service of Amsterdam from June 1,2020 through August 31, 2021. Symptoms were self-reported at time of requesting a test. Multivariable logistic regression models with generalized estimating equations were used to identify predictors of a positive test. Included symptoms were: cough, fever, loss of smell or taste, muscle ache, runny nose, shortness of breath, and throat ache; adjustments were made for age and gender, and stratification by month. Results: Overall, 12.0% of 773,680 tests in 432,213 unique individuals were positive. All symptoms were significantly associated with a positive test result, the strongest positive associations were: cough (aOR = 1.78, 95%CI = 1.75–1.80), fever (aOR = 2.11, 95%CI = 2.07–2.14), loss of smell or taste (aOR = 2.55, 95%CI = 2.50–2.61), and muscle ache (aOR = 2.38, 95%CI = 2.34–2.43). The adjusted odds ratios for loss of smell or taste slightly declined over time, while that for cough increased. Conclusion: Cough, fever, loss of smell or taste, and muscle ache appear to be most strongly associated with a positive SARS-CoV-2 test in symptomatic people of the general population who were tested. [ABSTRACT FROM AUTHOR]

The degree of attention individuals pay to olfactory cues (called odor awareness) influences the role of odors in everyday life. Particularly, odors produced by the human body (i.e., social odors) are able to carry a wide variety of information and to elicit a broad spectrum of emotional reactions, making them essential in interpersonal relationships. Hence, despite the assessment of awareness toward social odors is crucial, a proper tool is still lacking. Here, we designed and initially validated the Social Odor Scale (SOS), a 12-item scale designed to measure the individual differences in awareness towards different social odors. In Study 1, an exploratory factor analysis (EFA; KMO test: MSA = 0.78; Bartlett's test: χ2(78) = 631.34, p < 0.001; Chi-squared test: χ2(42) = 71.84, p = 0.003) suggests that the three factors structure was the model that best fit with the Italian version of the scale. The confirmatory factor analysis (CFA) supports a second-order model with one higher-order factor representing social odor awareness in general and three lower-order factors representing familiar, romantic partner, and stranger social odors. The final version of the scale presented a good fit (RMSEA = 0.012, SRMR = 0.069, CFI = 0.998, TLI = 0.997). In Study 2, CFA was performed in the German version of the scale confirming the validity of scale structure. Study 3 and 4 revealed that SOS total score and its subscales were positively correlated with other validated olfactory scales, but not with olfactory abilities. Moreover, SOS was found to be related to the gender of the participants: women reported to be more aware to social odors and, specifically, to familiar social odors than men. Overall, the results indicated that SOS is a valid and reliable instrument to assess awareness toward social odors in everyday life. [ABSTRACT FROM AUTHOR]

Objective: This cross-sectional observational study summarized the baseline characteristics of subjects who underwent COVID-19 molecular testing in a private medical centre located in the state of Selangor in Malaysia between 1 Oct 2020 and 31 Jan 2021. We compared the baseline characteristics between subjects who were tested positive and negative of SARS-CoV-2 infection, and identified risk factors which may be predictive of SARS-CoV-2 positivity. Methods and findings: A total of 36603 subjects who were tested for COVID-19 infection via molecular assays at Sunway Medical Centre between Oct 1, 2020 and Jan 31, 2021, and consented to participate in this observation study were included for analysis. Descriptive statistics was used to summarize the study cohort, whereas logistic regression analysis was used to identify risk factors associated with SARS-CoV-2 positivity. Among the reasons listed for COVID-19 screening were those who needed clearance for travelling, clearance to return to work, or clearance prior to hospital admission. They accounted for 67.7% of tested subjects, followed by the self-referred group (27.3%). Most of the confirmed cases were asymptomatic (62.6%), had no travel history (99.6%), and had neither exposure to SARS-CoV-2 confirmed cases (61.9%) nor exposure to patients under investigation (82.7%) and disease clusters (89.2%). Those who presented with loss of smell or taste (OR: 26.91; 95% CI: 14.81–48.92, p<0.001), fever (OR:3.97; 95% CI: 2.54–6.20, p<0.001), running nose (OR: 1.75; 95% CI:1.10–2.79, p = 0.019) or other symptoms (OR: 5.63; 95% CI:1.68–18.91, p = 0.005) were significantly associated with SARS-CoV-2 positivity in the multivariate logistic regression analysis. Conclusion: Our study showed that majority of patients seeking COVID-19 testing in a private healthcare setting were mainly asymptomatic with low epidemiological risk. Consequently, the average positivity rate was 1.2% compared to the national cumulative positivity rate of 4.65%. Consistent with other studies, we found that loss of smell or taste, fever and running nose were associated with SARS-CoV-2 positivity. We believe that strengthening the capacity of private health institutions is important in the national battle against the COVID-19 pandemic, emphasizing the importance of public-private partnership to improve the quality of clinical care. [ABSTRACT FROM AUTHOR]

Background: Qualitative olfactory (smell) dysfunctions are a common side effect of post-viral illness and known to impact quality of life and health status. Evidence is emerging that taste and smell loss are common symptoms of Covid-19 that may emerge and persist long after initial infection. The aim of the present study was to document the impact of post Covid-19 alterations to taste and smell. Methods: We conducted exploratory thematic analysis of user-generated text from 9000 users of the AbScent Covid-19 Smell and Taste Loss moderated Facebook support group from March 24 to 30th September 2020. Results: Participants reported difficulty explaining and managing an altered sense of taste and smell; a lack of interpersonal and professional explanation or support; altered eating; appetite loss, weight change; loss of pleasure in food, eating and social engagement; altered intimacy and an altered relationship to self and others. Conclusions: Our findings suggest altered taste and smell with Covid-19 may lead to severe disruption to daily living that impacts on psychological well-being, physical health, relationships and sense of self. More specifically, participants reported impacts that related to reduced desire and ability to eat and prepare food; weight gain, weight loss and nutritional insufficiency; emotional wellbeing; professional practice; intimacy and social bonding; and the disruption of people's sense of reality and themselves. Our findings should inform further research and suggest areas for the training, assessment and treatment practices of health care professionals working with long Covid. [ABSTRACT FROM AUTHOR]

Background: Research on COVID-19 during pregnancy has mainly focused on women hospitalized for COVID-19 or other reasons during their pregnancy. Little is known about COVID-19 in the general population of pregnant women. Objective: To describe the prevalence of COVID-19, symptoms, consequent healthcare use, and possible sources of COVID-19 exposure among a population-based sample of pregnant women residing in Northern California. Methods: We analyzed data from 19,458 members of Kaiser Permanente Northern California who were pregnant between January 2020 and April 2021 and responded to an online survey about COVID-19 testing, diagnosis, symptoms, and their experiences during the COVID-19 pandemic. Medical diagnosis of COVID-19 during pregnancy was defined separately by self-report and by documentation in electronic health records (EHR). We examined relationships of COVID-19 with sociodemographic factors, underlying comorbidities, and survey measures of COVID-19-like symptoms, consequent healthcare utilization, and possible COVID-19 exposures. Results: Among 19,458 respondents, the crude prevalence of COVID-19 was 2.5% (n = 494) according to self-report and 1.4% (n = 276) according to EHR. After adjustment, the prevalence of self-reported COVID-19 was higher among women aged <25 years compared with women aged ≥35 years (prevalence ratio [PR], 1.75, 95% CI: 1.23, 2.49) and among Hispanic women compared with White women (PR, 1.91, 95% CI: 1.53, 2.37). Prevalence of self-reported COVID-19 was higher among women affected by personal or partner job loss during the pandemic (PR, 1.23, 95% CI: 1.02, 1.47) and among women living in areas of high vs. low neighborhood deprivation (PR, 1.74, 95% CI: 1.33, 2.27). We did not observe differences in self-reported COVID-19 between women with and without underlying comorbidities. Results were similar for EHR-documented COVID-19. Loss of smell or taste was a unique and common symptom reported among women with COVID-19 (42.3% in self-reported; 54.0% in EHR-documented). Among women with symptomatic COVID-19, approximately 2% were hospitalized, 71% had a telehealth visit, and 75% quarantined at home. Over a third of women with COVID-19 reported no known exposure to someone with COVID-19. Conclusions: Observed COVID-19 prevalence differences by sociodemographic and socioeconomic factors underscore social and health inequities among reproductive-aged women. Women with COVID-19 reported unique symptoms and low frequency of hospitalization. Many were not aware of an exposure to someone with COVID-19. [ABSTRACT FROM AUTHOR]

Multiple neurological disorders are characterized by the abnormal accumulation of protein aggregates and the progressive impairment of complex behaviors. Our Drosophila studies demonstrate that middle-aged wild-type flies (WT, ~4-weeks) exhibit a marked accumulation of neural aggregates that is commensurate with the decline of the autophagy pathway. However, enhancing autophagy via neuronal over-expression of Atg8a (Atg8a-OE) reduces the age-dependent accumulation of aggregates. Here we assess basal locomotor activity profiles for single- and group-housed male and female WT flies and observed that only modest behavioral changes occurred by 4-weeks of age, with the noted exception of group-housed male flies. Male flies in same-sex social groups exhibit a progressive increase in nighttime activity. Infrared videos show aged group-housed males (4-weeks) are engaged in extensive bouts of courtship during periods of darkness, which is partly repressed during lighted conditions. Together, these nighttime courtship behaviors were nearly absent in young WT flies and aged Atg8a-OE flies. Previous studies have indicated a regulatory role for olfaction in male courtship partner choice. Coincidently, the mRNA expression profiles of several olfactory genes decline with age in WT flies; however, they are maintained in age-matched Atg8a-OE flies. Together, these results suggest that middle-aged male flies develop impairments in olfaction, which could contribute to the dysregulation of courtship behaviors during dark time periods. Combined, our results demonstrate that as Drosophila age, they develop early behavior defects that are coordinate with protein aggregate accumulation in the nervous system. In addition, the nighttime activity behavior is preserved when neuronal autophagy is maintained (Atg8a-OE flies). Thus, environmental or genetic factors that modify autophagic capacity could have a positive impact on neuronal aging and complex behaviors.

Olfactory impairment is associated with dementia and is a potential early biomarker of cognitive decline. We developed a novel olfactory threshold test called Sniff Bubble using rose odor-containing beads made with 2-phenylethyl alcohol. We aimed to define cut-off scores for this tool to help identify cognitive decline among elderly people. In total, 162 elderly people (mean age ± SD: 73.04 ± 8.73 years) were administered olfactory threshold and neurocognitive tests. For analyses, we divided the participants into two groups based on cognitive functioning, namely cognitive decline (n = 44) and normal cognition (n = 118) groups. The Sniff Bubble and YSK olfactory function test for olfactory threshold and the Structured Clinical Interview for DSM-5 Disorders-Clinician Version and Korean version of the Consortium to Establish a Registry for Alzheimer's Disease assessment packet for neurocognitive functioning were used. We used K-means cluster analyses and receiver operating characteristic (ROC) analyses to identify the most appropriate cut-off value. We established a positive correlation between the Sniff Bubble and neurocognitive function test scores (r = 0.431, p < 0.001). We defined the cut-off score, using the ROC curve analyses for Sniff Bubble scores, at 3 and higher with an area under the curve of 0.759 (p < 0.001). The Sniff Bubble test can adequately detect cognitive decline in elderly people and may be used clinically as the first step in the screening process. [ABSTRACT FROM AUTHOR]

The extent to which a nasal whiff of scent can exogenously orient visual spatial attention remains poorly understood in humans. In a series of seven studies, we investigated the existence of an exogenous capture of visual spatial attention by purely trigeminal (i.e., CO2) and both olfactory and trigeminal stimuli (i.e., eucalyptol). We chose these stimuli because they activate the trigeminal system which can be considered as an alert system and are thus supposedly relevant for the individual, and thus prone to capture attention. We used them as lateralized cues in a variant of a visual spatial cueing paradigm. In valid trials, trigeminal cues and visual targets were presented on the same side whereas in invalid trials they were presented on opposite sides. To characterize the dynamics of the cross-modal attentional capture, we manipulated the interval between the onset of the trigeminal cues and the visual targets (from 580 to 1870 ms). Reaction times in trigeminal valid trials were shorter than all other trials, but only when this interval was around 680 or 1170 ms for CO2 and around 610 ms for eucalyptol. This result reflects that both pure trigeminal and olfactory-trigeminal stimuli can exogenously capture humans' spatial visual attention. We discuss the importance of considering the dynamics of this cross-modal attentional capture. [ABSTRACT FROM AUTHOR]

Rapid diagnosis is key to curtailing the Covid-19 pandemic. One path to such rapid diagnosis may rely on identifying volatile organic compounds (VOCs) emitted by the infected body, or in other words, identifying the smell of the infection. Consistent with this rationale, dogs can use their nose to identify Covid-19 patients. Given the scale of the pandemic, however, animal deployment is a challenging solution. In contrast, electronic noses (eNoses) are machines aimed at mimicking animal olfaction, and these can be deployed at scale. To test the hypothesis that SARS CoV-2 infection is associated with a body-odor detectable by an eNose, we placed a generic eNose in-line at a drive-through testing station. We applied a deep learning classifier to the eNose measurements, and achieved real-time detection of SARS CoV-2 infection at a level significantly better than chance, for both symptomatic and non-symptomatic participants. This proof of concept with a generic eNose implies that an optimized eNose may allow effective real-time diagnosis, which would provide for extensive relief in the Covid-19 pandemic. [ABSTRACT FROM AUTHOR]

BackgroundRecent evidence suggests that a lower extent of the retronasal aroma release correspond to a higher amount of ad libitum food intake. This has been regarded as one of the bases of behavioral choices towards food consumption in obese people. In this pilot study we investigated the hypothesis that saliva from obese individuals could be responsible for an alteration of the retro-nasal aroma release. We tested this hypothesis in vitro, by comparing the release of volatiles from a liquid food matrix (wine) after its interaction with saliva from 28 obese (O) and 28 normal-weight (N) individuals.Methods and findingsAmplicon sequencing of the 16S rRNA V4 region indicated that Firmicutes and Actinobacteria were more abundant in O, while Proteobacteria and Fusobacteria dominated in N. Streptococcaceae were significantly more abundant in the O subjects and constituted 34% and 19% on average of the saliva microbiota of O and N subjects, respectively. The Total Antioxidant Capacity was higher in O vs N saliva samples. A model mouth system was used to test whether the in-mouth wine aroma release differs after the interaction with O or N saliva. In O samples, a 18% to 60% significant decrease in the mean concentration of wine volatiles was detected as a result of interaction with saliva, compared with N. This suppression was linked to biochemical differences in O and N saliva composition, which include protein content.ConclusionMicrobiological and biochemical differences were found in O vs N saliva samples. An impaired retronasal aroma release from white wine was detected in vitro and linked to compositional differences between saliva from obese and normal-weight subjects. Additional in vivo investigations on diverse food matrices could contribute to understanding whether a lower olfactory stimulation due to saliva composition can be a co-factor in the development/maintenance of obesity.

We measured frequency response functions between odorants and action potentials in two types of neurons in Drosophila antennal basiconic sensilla. CO2 was used to stimulate ab1C neurons, and the fruit odor ethyl butyrate was used to stimulate ab3A neurons. We also measured frequency response functions for light-induced action potential responses from transgenic flies expressing H134R-channelrhodopsin-2 (ChR2) in the ab1C and ab3A neurons. Frequency response functions for all stimulation methods were well-fitted by a band-pass filter function with two time constants that determined the lower and upper frequency limits of the response. Low frequency time constants were the same in each type of neuron, independent of stimulus method, but varied between neuron types. High frequency time constants were significantly slower with ethyl butyrate stimulation than light or CO2 stimulation. In spite of these quantitative differences, there were strong similarities in the form and frequency ranges of all responses. Since light-activated ChR2 depolarizes neurons directly, rather than through a chemoreceptor mechanism, these data suggest that low frequency dynamic properties of Drosophila olfactory sensilla are dominated by neuron-specific ionic processes during action potential production. In contrast, high frequency dynamics are limited by processes associated with earlier steps in odor transduction, and CO2 is detected more rapidly than fruit odor.

This study aims to highlight the relationships between the structure of smell compounds and their odors. For this purpose, heterogeneous data sources were screened, and 6038 odorant compounds and their known associated odors (162 odor notes) were compiled, each individual molecule being represented with a set of 1024 structural fingerprint. Several dimensional reduction techniques (PCA, MDS, t-SNE and UMAP) with two clustering methods (k-means and agglomerative hierarchical clustering AHC) were assessed based on the calculated fingerprints. The combination of UMAP with k-means and AHC methods allowed to obtain a good representativeness of odors by clusters, as well as the best visualization of the proximity of odorants on the basis of their molecular structures. The presence or absence of molecular substructures has been calculated on odorant in order to link chemical groups to odors. The results of this analysis bring out some associations for both the odor notes and the chemical structures of the molecules such as "woody" and "spicy" notes with allylic and bicyclic structures, "balsamic" notes with unsaturated rings, both "sulfurous" and "citrus" with aldehydes, alcohols, carboxylic acids, amines and sulfur compounds, and "oily", "fatty" and "fruity" characterized by esters and with long carbon chains. Overall, the use of UMAP associated to clustering is a promising method to suggest hypotheses on the odorant structure-odor relationships. [ABSTRACT FROM AUTHOR]

Introduction: Healthcare workers (HCW) treating COVID-19 patients are at high risk for infection and may also spread infection through their contact with vulnerable patients. Smell loss has been associated with SARS-CoV-2 infection, but it is unknown whether monitoring for smell loss can be used to identify asymptomatic infection among high risk individuals. In this study we sought to determine if tracking smell sensitivity and loss using an at-home assessment could identify SARS-CoV-2 infection in HCW. Methods and findings: We performed a prospective cohort study tracking 473 HCW across three months to determine if smell loss could predict SARS-CoV-2 infection in this high-risk group. HCW subjects completed a longitudinal, behavioral at-home assessment of olfaction with household items, as well as detailed symptom surveys that included a parosmia screening questionnaire, and real-time quantitative polymerase chain reaction testing to identify SARS-CoV-2 infection. Our main measures were the prevalence of smell loss in SARS-CoV-2-positive HCW versus SARS-CoV-2-negative HCW, and timing of smell loss relative to SARS-CoV-2 test positivity. SARS-CoV-2 was identified in 17 (3.6%) of 473 HCW. HCW with SARS-CoV-2 infection were more likely to report smell loss than SARS-CoV-2-negative HCW on both the at-home assessment and the screening questionnaire (9/17, 53% vs 105/456, 23%, P <.01). 6/9 (67%) of SARS-CoV-2-positive HCW reporting smell loss reported smell loss prior to having a positive SARS-CoV-2 test, and smell loss was reported a median of two days before testing positive. Neurological symptoms were reported more frequently among SARS-CoV-2-positive HCW who reported smell loss compared to those without smell loss (9/9, 100% vs 3/8, 38%, P <.01). Conclusions: In this prospective study of HCW, self-reported changes in smell using two different measures were predictive of SARS-CoV-2 infection. Smell loss frequently preceded a positive test and was associated with neurological symptoms. [ABSTRACT FROM AUTHOR]

Prostate cancer is the second leading cause of cancer death in men in the developed world. A more sensitive and specific detection strategy for lethal prostate cancer beyond serum prostate specific antigen (PSA) population screening is urgently needed. Diagnosis by canine olfaction, using dogs trained to detect cancer by smell, has been shown to be both specific and sensitive. While dogs themselves are impractical as scalable diagnostic sensors, machine olfaction for cancer detection is testable. However, studies bridging the divide between clinical diagnostic techniques, artificial intelligence, and molecular analysis remains difficult due to the significant divide between these disciplines. We tested the clinical feasibility of a cross-disciplinary, integrative approach to early prostate cancer biosensing in urine using trained canine olfaction, volatile organic compound (VOC) analysis by gas chromatography-mass spectroscopy (GC-MS) artificial neural network (ANN)-assisted examination, and microbial profiling in a double-blinded pilot study. Two dogs were trained to detect Gleason 9 prostate cancer in urine collected from biopsy-confirmed patients. Biopsy-negative controls were used to assess canine specificity as prostate cancer biodetectors. Urine samples were simultaneously analyzed for their VOC content in headspace via GC-MS and urinary microbiota content via 16S rDNA Illumina sequencing. In addition, the dogs' diagnoses were used to train an ANN to detect significant peaks in the GC-MS data. The canine olfaction system was 71% sensitive and between 70–76% specific at detecting Gleason 9 prostate cancer. We have also confirmed VOC differences by GC-MS and microbiota differences by 16S rDNA sequencing between cancer positive and biopsy-negative controls. Furthermore, the trained ANN identified regions of interest in the GC-MS data, informed by the canine diagnoses. Methodology and feasibility are established to inform larger-scale studies using canine olfaction, urinary VOCs, and urinary microbiota profiling to develop machine olfaction diagnostic tools. Scalable multi-disciplinary tools may then be compared to PSA screening for earlier, non-invasive, more specific and sensitive detection of clinically aggressive prostate cancers in urine samples. [ABSTRACT FROM AUTHOR]

Background: Early recognition of COVID-19 cases is essential for effective public health measures aimed at isolation of individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS–COV-2). The objective of this study was to describe characteristics, self-reported symptoms, and predictors of testing positive for SARS-CoV-2 infection in a community-based sample. Methods and findings: This was a cross-sectional nationwide survey of adults in the US conducted between April 24 through May 13, 2020. The survey targeted a representative sample of approximately 5,000 respondents. The rate of COVID-19 cases and testing, most frequently reported symptoms, symptom severity, treatment received, impact of COVID-19 on mental and physical health, and factors predictive of testing positive were assessed. Most of the 5,203 participants (85.6%) reported no COVID-19-like symptoms. Of the 747 (14.5%) participants reporting COVID-19-like symptoms, 367 (49.1%) obtained a diagnostic test. Eighty-nine participants (24.3%) reported a positive COVID-19 test result, representing 1.7% of the total sample. For those testing positive, the most common symptoms were dry cough, fever, and shortness of breath/difficulty breathing. Those who tested positive were more likely to report greater symptom severity versus those who tested negative. Severe dry cough, new loss of taste or smell, trouble waking up, living with someone experiencing symptoms, recent international travel, respiratory issues, and reporting ethnicity of Black or African American were predictive of testing positive. Conclusions: This study assessed the impact of COVID-19 using community-level self-reported data across the US during the peak of most stay at home' orders. Self-reported symptoms and risk factors identified in this study are consistent with the clinical profile emerging for COVID-19. In the absence of widespread testing, this study demonstrates the utility of a representative US community-based sample to provide direct-reported symptoms and outcomes to quickly identify high-risk individuals who are likely to test positive and should consider taking greater precautions. [ABSTRACT FROM AUTHOR]

Insect Olfactory Receptors (ORs) are diverse family of membrane protein receptors responsible for most of the insect olfactory perception and communication, and hence they are of utmost importance for developing repellents or pesticides. Accurate gene prediction of insect ORs from newly sequenced genomes is an important but challenging task. We have developed a dedicated webserver, 'insectOR', to predict and validate insect OR genes using multiple gene prediction algorithms, accompanied by relevant validations. It is possible to employ this server nearly automatically and perform rapid prediction of the OR gene loci from thousands of OR-protein-to-genome alignments, resolve gene boundaries for tandem OR genes and refine them further to provide more complete OR gene models. InsectOR outperformed the popular genome annotation pipelines (MAKER and NCBI eukaryotic genome annotation) in terms of overall sensitivity at base, exon and locus level, when tested on two distantly related insect genomes. It displayed more than 95% nucleotide level precision in both tests. Finally, given the same input data and parameters, InsectOR missed less than 2% gene loci, in contrast to 55% loci missed by MAKER for Drosophila melanogaster. The webserver is freely available on the web at http://caps.ncbs.res.in/insectOR/ and the basic package can be downloaded from https://github.com/sdk15/insectOR for local use. This tool will allow biologists to perform quick preliminary identification of insect olfactory receptor genes from newly sequenced genomes and also assist in their further detailed annotation. Its usage can also be extended to other divergent gene families. [ABSTRACT FROM AUTHOR]

High-frequency oscillations of the frontal cortex are involved in functions of the brain that fuse processed data from different sensory modules or bind them with elements stored in the memory. These oscillations also provide inhibitory connections to neural circuits that perform lower-level processes. Deficit in the performance of these oscillations has been examined as a marker for Alzheimer's disease (AD). Additionally, the neurodegenerative processes associated with AD, such as the deposition of amyloid-beta plaques, do not occur in a spatially homogeneous fashion and progress more prominently in the medial temporal lobe in the early stages of the disease. This region of the brain contains neural circuitry involved in olfactory perception. Several studies have suggested that olfactory deficit can be used as a marker for early diagnosis of AD. A quantitative assessment of the performance of the olfactory system can hence serve as a potential biomarker for Alzheimer's disease, offering a relatively convenient and inexpensive diagnosis method. This study examines the decline in the perception of olfactory stimuli and the deficit in the performance of high-frequency frontal oscillations in response to olfactory stimulation as markers for AD. Two measurement modalities are employed for assessing the olfactory performance: 1) An interactive smell identification test is used to sample the response to a sizable variety of odorants, and 2) Electroencephalography data are collected in an olfactory perception task with a pair of selected odorants in order to assess the connectivity of frontal cortex regions. Statistical analysis methods are used to assess the significance of selected features extracted from the recorded modalities as Alzheimer's biomarkers. Olfactory decline regressed to age in both healthy and mild AD groups are evaluated, and single- and multi-modal classifiers are also developed. The novel aspects of this study include: 1) Combining EEG response to olfactory stimulation with behavioral assessment of olfactory perception as a marker of AD, 2) Identification of odorants most significantly affected in mild AD patients, 3) Identification of odorants which are still adequately perceived by mild AD patients, 4) Analysis of the decline in the spatial coherence of different oscillatory bands in response to olfactory stimulation, and 5) Being the first study to quantitatively assess the performance of olfactory decline due to aging and AD in the Iranian population. [ABSTRACT FROM AUTHOR]

The rodent whisker system is a major model for understanding neural mechanisms for tactile sensation of surface texture (roughness). Rats discriminate surface texture using the whiskers, and several theories exist for how texture information is physically sensed by the long, moveable macrovibrissae and encoded in spiking of neurons in somatosensory cortex. However, evaluating these theories requires a psychometric curve for texture discrimination, which is lacking. Here we trained rats to discriminate rough vs. fine sandpapers and grooved vs. smooth surfaces. Rats intermixed trials at macrovibrissa contact distance (nose >2 mm from surface) with trials at shorter distance (nose

Objectives: In this study, we aimed to study the clinical presentations, and viral clearance of SARS-COV-2 positive quarantined individuals. Design: Cross-sectional study. Setting: Governmental- designated facility in the eastern province, Saudi Arabia. Participants: 128 laboratory-confirmed COVID-19 quarantined individuals who had a history of travel abroad in the last 14 days before the quarantine or were in direct contact with laboratory-confirmed cases. The study was from March 18th-till April 16th. Primary and secondary measures: The clinical presentation, prevalence of asymptomatic carriers among SARS-COV-2 positive quarantined subjects, and the difference between virus clearance among symptomatic and asymptomatic individuals. Results: Sixty-nine of the 128 residents (54%) were completely asymptomatic until the end of the study. The remaining 59 residents (46%) had only mild symptoms. The most common symptom was a sudden loss of smell and taste, accounting for 47.5%. The median time to virus clearance was significantly different between the two groups. Symptomatic residents cleared the virus at a median of 17 days (95% CI, 12.4–21.6) from the first positive PCR vs. 11days (95% CI, 8.7–13.3) in the asymptomatic group (P = 0.011). False-negative test results occurred in 18.8% of the total residents and false-positive results in 3%. Conclusion: The prevalence of asymptomatic carriers among quarantined travelers and those identified by contact tracing is high in our study. Therefore, testing, tracing, and isolating travelers and contacts of laboratory-confirmed cases, regardless of symptoms, were very effective measures for early disease identification and containment. Loss of taste and smell were the most common presentations in our mild symptomatic residents and should be used as a screening tool for COVID-19. The persistent positive PCR beyond 14 days observed in the mild symptomatic residents despite being symptoms free, warrant further studies to determine its implications on disease spread and control. [ABSTRACT FROM AUTHOR]