Nevin Manimala

Neural Comput. 2021 Jul 19:1-24. doi: 10.1162/neco_a_01421. Online ahead of print.

ABSTRACT

In trichromats, color vision entails the projection of an infinite-dimensional space (the one containing all possible electromagnetic power spectra) onto the three-dimensional space that modulates the activity of the three types of cones. This drastic reduction in dimensionality gives rise to metamerism, that is, the perceptual chromatic equivalence between two different light spectra. The classes of equivalence of metamerism are revealed by color-matching experiments in which observers adjust the intensity of three monochromatic light beams of three preset wavelengths (the primaries) to produce a mixture that is perceptually equal to a given monochromatic target stimulus. Here we use the linear relation between the color matching functions and the absorption probabilities of each type of cone to find particularly useful triplets of primaries. As a second goal, we also derive an analytical description of the trial-to-trial variability and the correlations of color matching functions stemming from Poissonian noise in photon capture. We analyze how the statistical properties of the responses to color-matching experiments vary with the retinal composition and the wavelengths of peak absorption probability, and compare them with experimental data on subject-to-subject variability obtained previously.

PMID:34280301 | DOI:10.1162/neco_a_01421

PLoS One. 2021 Jul 19;16(7):e0254807. doi: 10.1371/journal.pone.0254807. eCollection 2021.

ABSTRACT

Biologics are recommended in Japan to treat moderate to severe Crohn’s Disease (CD). Although CD is associated with high direct costs in Japan, updated information after ustekinumab’s approval is unavailable. We aimed to evaluate the healthcare resource utilization (HRU) and associated direct costs from the payer’s perspective in Japan. Claims data (2010-2018) were retrospectively analyzed to identify patients with CD. HRU and associated costs were evaluated for 12 months before and after biologic initiation and followed-up till 36 months post-initiation. Outcomes were reported using descriptive statistics. Among the included patients (n = 3,496), 1,783 were on biologics and 1,713 were on non-biologics. Mean (SD) age was 36.4 (13.2) years and patients were predominantly male (76.1%). Patients aged 18-39 years were affected with CD the most (55.3%). Biologic initiation was associated with a reduction in inpatient stay, length of stay, outpatient visits, and associated costs; and an increase in pharmacy costs and total costs after 12 months. Extended follow-up showed a decreasing trend in HRU and costs till 24 months but an increase after 36 months. These findings demonstrated reduction in clinical burden and slight increase in economic burden with biologics. However, indirect costs also need to be evaluated.

PMID:34280242 | DOI:10.1371/journal.pone.0254807

PLoS One. 2021 Jul 19;16(7):e0254872. doi: 10.1371/journal.pone.0254872. eCollection 2021.

ABSTRACT

BACKGROUND: COVID-19 is only partly understood, and the level of evidence available in terms of pathophysiology, epidemiology, therapy, and long-term outcome remains limited. During the early phase of the pandemic, it was necessary to effectively investigate all aspects of this new disease. Autopsy can be a valuable procedure to investigate the internal organs with special techniques to obtain information on the disease, especially the distribution and type of organ involvement.

METHODS: During the first wave of COVID-19 in Germany, autopsies of 19 deceased patients were performed. Besides gross examination, the organs were analyzed with standard histology and polymerase-chain-reaction for SARS-CoV-2. Polymerase chain reaction positive localizations were further analyzed with immunohistochemistry and RNA-in situ hybridization for SARS-CoV-2.

RESULTS: Eighteen of 19 patients were found to have died due to COVID-19. Clinically relevant histological changes were only observed in the lungs. Diffuse alveolar damage in considerably different degrees was noted in 18 cases. Other organs, including the central nervous system, did not show specific micromorphological alterations. In terms of SARS-CoV-2 detection, the focus remains on the upper airways and lungs. This is true for both the number of positive samples and the viral load. A highly significant inverse correlation between the stage of diffuse alveolar damage and viral load was found on a case and a sample basis. Mediastinal lymph nodes and fat were also affected by the virus at high frequencies. By contrast, other organs rarely exhibited a viral infection. Moderate to strong correlations between the methods for detecting SARS-CoV-2 were observed for the lungs and for other organs.

CONCLUSIONS: The lung is the most affected organ in gross examination, histology and polymerase chain reaction. SARS-CoV-2 detection in other organs did not reveal relevant or specific histological changes. Moreover, we did not find CNS involvement.

PMID:34280238 | DOI:10.1371/journal.pone.0254872

PLoS One. 2021 Jul 19;16(7):e0254824. doi: 10.1371/journal.pone.0254824. eCollection 2021.

ABSTRACT

BACKGROUND: Breastfeeding is the feeding of an infant or young child with breast milk directly from female human breasts. It confers short-term and long-term benefits for both child and mother, including helping to protect children against a variety of acute and chronic disorders. In mothers, breastfeeding (BF) reduces postpartum bleeding, enhances accelerated involution of the uterus, and plays a crucial role in child spacing. Fathers have an important but often neglected role in the promotion of healthy breastfeeding practices. Evidence shows that mothers who have a supportive and encouraging partner are more likely to plan to breastfeed for a longer duration. So, this study was aimed to assess knowledge and associated factors towards breastfeeding practice among fathers.

METHODS: A community-based cross-sectional study was conducted in Gurage Zone among 597 fathers. One stage cluster sampling technique was used to select study participants. An interviewer-administered questionnaire was used to collect the data and it was checked for consistency and completeness and entered into epi data and exported to SPSS for analysis. Bivariate and multivariate logistic regression analysis was done to identify independent predictors. P-value < 0.05 was considered to declare a result as statistically significant.

RESULT: In this study, a total of 585 participants were involved making a response rate of 98%. The overall knowledge status of participants was 341 (58.3%). The mean age of participants was 29.5 (SD±4.5). Urban residence, educational status, exposure to media, having more than one baby at home, and accompany his wife during health-seeking were independent predictors of knowledge status.

CONCLUSION: This study has shown the level of knowledge of fathers towards breastfeeding in the study area was low (58.3%). Residence, two or more babies at home, accompany during ANC, and indexed infant illness was independent predictors of knowledge status of fathers towards breastfeeding. Policymakers and possible stack holders should better focus on the improvement of knowledge because the knowledge determines the overall condition of the family including the psychological development of the children that affect their life especially in a country like Ethiopia in which most of the decisions are made by them. Other researchers focus on the interaction of parents and the child and feeding disorders.

PMID:34280223 | DOI:10.1371/journal.pone.0254824

PLoS One. 2021 Jul 19;16(7):e0254661. doi: 10.1371/journal.pone.0254661. eCollection 2021.

ABSTRACT

BACKGROUND: The association between psoriasis and the risk of cancer has been investigated in numerous studies utilising electronic health records (EHRs), with conflicting results in the extent of the association.

OBJECTIVES: To assess concordance and timing of cancer recording between primary care, hospital and death registration data for people with and without psoriasis.

METHODS: Cohort studies delineated using primary care EHRs from the Clinical Practice Research Datalink (CPRD) GOLD and Aurum databases, with linkage to hospital episode statistics (HES), Office for National Statistics (ONS) mortality data and indices of multiple deprivation (IMD). People with psoriasis were matched to those without psoriasis by age, sex and general practice. Cancer recording between databases was investigated by proportion concordant, that being the presence of cancer record in both source and comparator datasets. Delay in recording cancer diagnoses between CPRD and HES records and predictors of discordance were also assessed.

RESULTS: 58,904 people with psoriasis and 350,592 comparison patients were included using CPRD GOLD; whereas 213,400 people with psoriasis and 1,268,998 comparison patients were included in CPRD Aurum. For all cancer records (excluding keratinocyte), concordance between CPRD and HES was greater than 80%. Concordance for same-site cancer records was markedly lower (<68% GOLD-linked data; <72% Aurum-linked data). Concordance of non-Hodgkin lymphoma and liver cancer recording between CPRD and HES was lower for people with psoriasis compared to those without.

CONCLUSIONS: Concordance between CPRD and HES is poor when restricted to cancers of the same site, with greater discordance in people with psoriasis for some cancers of specific sites. The use of linked patient-level data is an important step in reducing misclassification of cancer outcomes in epidemiological studies using routinely collected electronic health records.

PMID:34280213 | DOI:10.1371/journal.pone.0254661

PLoS One. 2021 Jul 19;16(7):e0253464. doi: 10.1371/journal.pone.0253464. eCollection 2021.

ABSTRACT

This study examines the relationship between economic growth, renewable energy consumption, and carbon emissions in Iran between 1975-2017, and the bounds testing approach to cointegration and the asymmetric method was used in this study. The results reveal that in the long run increase in renewable energy consumption and CO2 emissions causes an increase in real GDP per capita. Meanwhile, the decrease in renewable energy has the same effect, but GDP per capita reacts more strongly to the rise in renewable energy than the decline. Besides, in the long run, a reduction of CO2 emissions has an insignificant impact on GDP per capita. Furthermore, the results from asymmetric tests suggest that reducing CO2 emissions and renewable energy consumption do not have an essential role in decreasing growth in the short run. In contrast, an increase in renewable energy consumption and CO2 emissions do contribute to boosting the growth. These results may be attributable to the less renewable energy in the energy portfolio of Iran. Additionally, the coefficients on capital and labor are statistically significant, and we discuss the economic implications of the results and propose specific policy recommendations.

PMID:34280209 | DOI:10.1371/journal.pone.0253464

PLoS One. 2021 Jul 19;16(7):e0254403. doi: 10.1371/journal.pone.0254403. eCollection 2021.

ABSTRACT

BACKGROUND: COVID-19 poses a severe threat worldwide. This study analyzes its propagation and evaluates statistically the effect of mobility restriction policies on the spread of the disease.

METHODS: We apply a variation of the stochastic Susceptible-Infectious-Recovered model to describe the temporal-spatial evolution of the disease across 33 provincial regions in China, where the disease was first identified. We employ Bayesian Markov Chain Monte-Carlo methods to estimate the model and to characterize a dynamic transmission network, which enables us to evaluate the effectiveness of various local and national policies.

RESULTS: The spread of the disease in China was predominantly driven by community transmission within regions, which dropped substantially after local governments imposed various lockdown policies. Further, Hubei was only the epicenter of the early epidemic stage. Secondary epicenters, such as Beijing and Guangdong, had already become established by late January 2020. The transmission from these epicenters substantially declined following the introduction of mobility restrictions across regions.

CONCLUSIONS: The spatial transmission network is able to differentiate the effect of the local lockdown policies and the cross-region mobility restrictions. We conclude that both are important policy tools for curbing the disease transmission. The coordination between central and local governments is important in suppressing the spread of infectious diseases.

PMID:34280197 | DOI:10.1371/journal.pone.0254403

PLoS Med. 2021 Jul 19;18(7):e1003707. doi: 10.1371/journal.pmed.1003707. eCollection 2021 Jul.

ABSTRACT

BACKGROUND: Angiotensin receptor blockers (ARBs) may have protective effects against dementia occurrence in patients with hypertension (HTN). However, whether telmisartan, an ARB with peroxisome proliferator-activated receptor γ (PPAR-γ)-modulating effects, has additional benefits compared to other ARBs remains unclear.

METHODS AND FINDINGS: Between 1997 and 2013, 2,166,944 type 2 diabetes mellitus (T2DM) patients were identified from the National Health Insurance Research Database of Taiwan. Patients with HTN using ARBs were included in the study. Patients with a history of stroke, traumatic brain injury, or dementia were excluded. Finally, 65,511 eligible patients were divided into 2 groups: the telmisartan group and the non-telmisartan ARB group. Propensity score matching (1:4) was used to balance the distribution of baseline characteristics and medications. The primary outcome was the diagnosis of dementia. The secondary outcomes included the diagnosis of Alzheimer disease and occurrence of symptomatic ischemic stroke (IS), any IS, and all-cause mortality. The risks between groups were compared using a Cox proportional hazard model. Statistical significance was set at p < 0.05. There were 2,280 and 9,120 patients in the telmisartan and non-telmisartan ARB groups, respectively. Patients in the telmisartan group had a lower risk of dementia diagnosis (telmisartan versus non-telmisartan ARBs: 2.19% versus 3.20%; HR, 0.72; 95% CI, 0.53 to 0.97; p = 0.030). They also had lower risk of dementia diagnosis with IS as a competing risk (subdistribution HR, 0.70; 95% CI, 0.51 to 0.95; p = 0.022) and with all-cause mortality as a competing risk (subdistribution HR, 0.71; 95% CI, 0.53 to 0.97; p = 0.029). In addition, the telmisartan users had a lower risk of any IS (6.84% versus 8.57%; HR, 0.79; 95% CI, 0.67 to 0.94; p = 0.008) during long-term follow-up. Study limitations included potential residual confounding by indication, interpretation of causal effects in an observational study, and bias caused by using diagnostic and medication codes to represent real clinical data.

CONCLUSIONS: The current study suggests that telmisartan use in hypertensive T2DM patients may be associated with a lower risk of dementia and any IS events in an East-Asian population.

PMID:34280191 | DOI:10.1371/journal.pmed.1003707

PLoS Genet. 2021 Jul 19;17(7):e1009665. doi: 10.1371/journal.pgen.1009665. Online ahead of print.

ABSTRACT

Wright’s inbreeding coefficient, FST, is a fundamental measure in population genetics. Assuming a predefined population subdivision, this statistic is classically used to evaluate population structure at a given genomic locus. With large numbers of loci, unsupervised approaches such as principal component analysis (PCA) have, however, become prominent in recent analyses of population structure. In this study, we describe the relationships between Wright’s inbreeding coefficients and PCA for a model of K discrete populations. Our theory provides an equivalent definition of FST based on the decomposition of the genotype matrix into between and within-population matrices. The average value of Wright’s FST over all loci included in the genotype matrix can be obtained from the PCA of the between-population matrix. Assuming that a separation condition is fulfilled and for reasonably large data sets, this value of FST approximates the proportion of genetic variation explained by the first (K – 1) principal components accurately. The new definition of FST is useful for computing inbreeding coefficients from surrogate genotypes, for example, obtained after correction of experimental artifacts or after removing adaptive genetic variation associated with environmental variables. The relationships between inbreeding coefficients and the spectrum of the genotype matrix not only allow interpretations of PCA results in terms of population genetic concepts but extend those concepts to population genetic analyses accounting for temporal, geographical and environmental contexts.

PMID:34280184 | DOI:10.1371/journal.pgen.1009665

Am J Trop Med Hyg. 2021 Jul 19:tpmd210266. doi: 10.4269/ajtmh.21-0266. Online ahead of print.

ABSTRACT

Annually, about 2.7 million snakebite envenomings occur worldwide, primarily affecting those living in rural regions. Effective treatment exists but is scarce, and traditional treatments are commonly used. To inform context-specific policies in Kenya, this study aimed to determine the health-seeking behavior and the health, social, and economic burden of snakebites in rural communities. Nonprobability sampling was used to survey 382 respondents from four snakebite-endemic counties, from February to August 2020, using a structured questionnaire. Descriptive statistics, Fisher’s exact tests, binary logistic regressions, and Mantel-Haenszel tests were used for analysis. Life-time experience with snakebites included 13.1% of respondents who reported being personally bitten and 37.4% who reported knowing of a community member being bitten. Respondents reported death after a snakebite in 9.1% of bitten community members and in 14.6% of bitten family members. Risk of snakebite was not significantly associated with sex, educational level, or occupation. Snakebite victims were most often walking (38%) or farming (24%) when bitten. Of those bitten, 58% went to a health facility, 30% sought traditional treatment, and 12% first went to a traditional healer before visiting a facility. Significant differences existed in perceptions on the financial consequences of snakebites among those who had been personally bitten and those who had observed a snakebite. Most commonly mentioned preventive measures were wearing shoes and carrying a light in the dark. Community engagement, including engagement with traditional healers, is needed to reduce snakebites. This should be done through education and sensitization to improve used preventive measures and effective health-seeking behavior.

PMID:34280130 | DOI:10.4269/ajtmh.21-0266