Dose-response relationship between risk factors and incidence of COVID-19 in 325 hospitalized patients:A multicenter retrospective cohort study

BACKGROUND The epidemiological and clinical characteristics of coronavirus disease 2019(COVID-19)patients have been widely reported,but the assessment of doseresponse relationships and risk factors for mortality and severe cases and clinical outcomes remain unclear.AIM To determine the dose-response relationship between risk factors and incidence of COVID-19.METHODS In this retrospective,multicenter cohort study,we included patients with confirmed COVID-19 infection who had been discharged or had died by February 6,2020.We used multivariable logistic regression and Cox proportional hazard models to determine the dose-response relationship between risk factors and incidence of COVID-19.RESULTS It clarified that increasing risk of in-hospital death were associated with older age(HR:1.04,95%CI:1.01-1.09),higher lactate dehydrogenase[HR:1.04,95%confidence interval(CI):1.01-1.10],C-reactive protein(HR:1.10,95%CI:1.01-1.23),and procalcitonin(natural log-transformed HR:1.88,95%CI:1.22-2.88),and D-dimer greater than 1μg/m L at admission(natural log transformed HR:1.63,95%CI:1.03-2.58)by multivariable regression.D-dimer and procalcitonin were logarithmically correlated with COVID-19 mortality risk,while there was a linear dose-response correlation between age,lactate dehydrogenase,D-dimer and procalcitonin,independent of established risk factors.CONCLUSION Higher lactate dehydrogenase,D-dimer,and procalcitonin levels were independently associated with a dose-response increased risk of COVID-19 mortality.

A Study on the Dose-Response Relationship between Asbestos Exposure Level and Asbestosis among Workers in a Chinese Chrysotile Product Factory

The dose-response relationship for asbestos exposure in a chrysotile product factory was studied. The past gravimetric dust concentration values, obtained from different worksites, were converted into fiber concentration values according to conversion factors that were worked out by simultaneous sampling in this study. The conversions were made so that exposure could be expressed in fiber-years (f-yr). Asbestosis was diagnosed on the basis of chest radiographs and occupational histories. Cumulative dust exposure (f-yr) was calculated up to the date of diagnosis for asbestosis patients, and up to September 1982 for the remaining workers. A dose-response relationship expressed as fiber-years exposed vs cumulative prevalence of asbestosis was established by the life table method on the basis of these data. Predicted 3 and 1% prevalence of asbestosis corresponded to 43 and 22 f-yr exposure, respectively. Considering that a worker can work for 35 years, these doses are commensurate with dust concentrations of 1.22 and 0.63 f/ml, respectively. It is recommended that 1 f/ml be taken as the maximum allowable concentration of airborne asbestos dust for the workplace with an anticipated prevalence of about 2% asbestosis after 35 years of exposure. 1990 Academic Press, Inc.

Dose-response relationship of lung cancer to amount smoked, duration and age starting

AIM: To quantify smoking/lung cancer relationships accurately using parametric modelling. METHODS: Using the International Epidemiological Studies on Smoking and Lung Cancer database of all epidemiological studies of 100+ lung cancer cases published before 2000, we analyzed 97 blocks of data for amount smoked, 35 for duration of smoking, and 27 for age started. Pseudo-numbers of cases and controls(or at risk) estimated from RRs by dose level formed the data modelled. We fitted various models relating loge RR to dose(d), including βd, βdY and βloge(1 + Wd),and investigated goodness-of-fit and heterogeneity between studies. RESULTS: The best-fitting models for loge RR were0.833 loge [1 +(8.1c/10)] for cigarettes/d(c), 0.792(y/10)0.74 for years smoked(y) and 0.176 [(70- a)/10]1.44 for age of start(a). Each model fitted well overall, though some blocks misfitted. RRs rose from 3.86 to 22.31 between c = 10 and 50, from 2.21 to 13.54 between y = 10 and 50, and from 3.66 to 8.94 between a = 30 and 12.5. Heterogeneity(P < 0.001) existed by continent for amount, RRs for 50 cigarettes/d being 7.23(Asia), 26.36(North America) and 22.16(Europe). Little heterogeneity was seen for duration of smoking or age started. CONCLUSION: The models describe the dose-relationships well, though may be biased by factors including misclassification of smoking status and dose.

Comparison of Two Dose-response Relationship of Noise Exposure Evaluation Results with High Frequency Hearing Loss

Background:Complex noise and its relation to hearing loss are difficult to measure and evaluate.In complex noise measurement,individual exposure results may not accurately represent lifetime noise exposure.Thus,the mean LAeq,8 h values of individuals in the same workgroup were also used to represent LAeq,8h in our study.Our study aimed to explore whether the mean exposure levels of workers in the same workgroup represented real noise exposure better than individual exposure levels did.Methods:A cross-sectional study was conducted to establish a model for cumulative noise exposure (CNE) and hearing loss in 205 occupational noise-exposed workers who were recruited from two large automobile manufacturers in China.We used a personal noise dosimeter and a questionnaire to determine the workers' occupational noise exposure levels and exposure times,respectively.A qualified audiologist used standardized audiometric procedures to assess hearing acuity after at least 16 h of noise avoidance.Results:We observed that 88.3％ of workers were exposed to more than 85 dB(A) of occupational noise (mean:89.3 ± 4.2 dB(A)).The personal CNE (CNEp) and workgroup CNE (CNEg) were 100.5 ± 4.7 dB(A) and 100.5 ± 2.9 dB(A),respectively.In the binary logistic regression analysis,we established a regression model with high-frequency hearing loss as the dependent variable and CNE as the independent variable.The Wald value was 5.014 with CNEp as the independent variable and 8.653 with CNEg as the independent variable.Furthermore,we found that the figure for CNEg was more similar to the stationary noise reference than CNEp was.The CNEg model was better than the CNEp model.In this circumstance,we can measure some subjects instead of the whole workgroup and save manpower.Conclusions:In a complex noise environment,the measurements of average noise exposure level of the workgroup can improve the accuracy and save manpower.

What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships

Volume is an important attribute used in many forest management decisions.Data from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume equation.When density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height measure.When density was not included(Volume=f(Diameter,Height)),the opposite was true.For models with density included,moment-based estimators of stand diameter and height performed better than all other measures.For models without density,largest tree estimators of stand diameter and height performed better than other measures.The overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses.

Three anti-inflammatory polysaccharides from Lonicera japonica Thunb.:insights into the structure-function relationships

This study demonstrates the feasibility of producing three polysaccharides(neutral LJP-1,acidic LJP-2 and acidic LJP-3)with significant in vitro and in vivo anti-inflammatory activities from the flowers of Lonicera japonica.The three polysaccharides differed in chemical composition,molecular weight(Mw)distribution,glycosidic linkage pattern,functional groups and morphology.They exhibited excellent protective effects(in a dose-dependent manner)in lipopolysaccharide-injured RAW264.7 macrophages and Cu SO4-damaged zebrafish via reducing NO production and inhibiting the overexpressions of inflammation-related transcription factors,inflammatory proteins and cytokines in the NF-κB/MAPK signaling pathways.Their antiinflammatory effects varied owing to their different molecular characteristics and chemical compositions.Overall,LJP-2 at 400μg/m L was the most effective.LJP-2 consisted mainly of→5)-α-L-Araf(1→,→4)-α-LGalp A(1→and→2)-α-L-Rhap(1→residues with terminal T-β-D-Glcp.Thus,honeysuckle flowers are good sources of anti-inflammatory polysaccharides,and precise fractionation enables the production of potent antiinflammatory agents for the development of functional foods and healthcare products.

Relationship between Kawasaki disease and abdominal pain

This editorial presents an analysis of an article recently published in the World Journal of Clinical Cases.Kawasaki disease(KD)is a well-known pediatric vasculitis characterized by fever,rash,conjunctivitis,oral mucosal changes,and swelling of the extremities.This editorial aims to delve into the intricate relationship between KD and abdominal pain,drawing insights from recent research findings to provide a comprehensive understanding and potential avenues for future investigation.

Elucidating the structure-activity relationship of Cu-Ag bimetallic catalysts for electrochemical CO_(2) reduction

Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst design.Herein,we prepared two Cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of Cu nanowires.When tested in a flow cell,the Cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the top.The catalysts were further studied in the H-cell and zero-gap MEA cell.It was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic catalysts.Our work elucidates the structure-activity relationship of bimetallic catalysts for CO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity.

Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low resilience.The determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological restoration.We proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic composition.We described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and soils.All three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia subalata.The distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt concentration.We provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local conditions.Failure to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem services.This study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

The Relationship between Father-Love Absence and Loneliness:Based on the Perspective of the Social Functionalist Theory and the Social Needs Theory

Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-love absence on individual loneliness are not clear.Based on the social functionalist theory and the social needs theory,this study examines the influence of individual fatherlove absence on loneliness and its underlying mechanisms.A questionnaire survey was administered to 319 junior high school students and 1,476 high school students.The results showed that adolescents with father-love absence had higher levels of loneliness,and that father-love absence affected loneliness levels through mediating pathways of individual gratitude,peer relationships,and gratitude to peer relationships.This study not only confirms the negative effects of father-love absence on adolescents’loneliness,but also explains the mediate roles of individual gratitude and peer relationships.It enriches the theoretical system related to family education and has important theoretical and practical implications for further interventions on adolescents’mental health from the perspective of fatherless parenting.

Different mechanisms underlie similar species-area relationships in two tropical archipelagoes

Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China Sea.We found positive plant species-area relationships for both coral and continental archipelagoes.However,our results showed that different mechanisms contributed to similar plant species-area relationships between the two archipelagoes.For coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species diversity.By contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental islands.Intriguingly,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two archipelagoes.In summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental islands.More generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands.

A Large-Scale Group Decision Making Model Based on Trust Relationship and Social Network Updating

With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that considers the trust relationship among decisionmakers(DMs).In the process of consensusmeasurement:the social network is constructed according to the social relationship among DMs,and the Louvain method is introduced to classify social networks to form subgroups.In this study,the weights of each decision maker and each subgroup are computed by comprehensive network weights and trust weights.In the process of consensus improvement:A feedback mechanism with four identification and two direction rules is designed to guide the consensus of the improvement process.Based on the trust relationship among DMs,the preferences are modified,and the corresponding social network is updated to accelerate the consensus.Compared with the previous research,the proposedmodel not only allows the subgroups to be reconstructed and updated during the adjustment process,but also improves the accuracy of the adjustment by the feedbackmechanism.Finally,an example analysis is conducted to verify the effectiveness and flexibility of the proposed method.Moreover,compared with previous studies,the superiority of the proposed method in solving the LGDM problem is highlighted.

Research on the Evaluation System of Community Daycare Center Planning and Implementation from the Perspective of Subject-Object Relationships

Through literature review,we found that evaluations of urban planning implementation often focus narrowly on either the subject(stakeholders)or the object(projects),while micro-level aspects such as site selection and construction are primarily considered within the context of planning implementation.There is insufficient research on the evaluation of implementation.Community daycare centers play a crucial role in the community home care model,yet there is relatively little research on their usage efficiency,satisfaction levels,and spatial evaluation of planning implementation.Based on the theoretical understanding of the human environment,including the subject,object,and their interactions,an evaluation system for the planning and implementation of community day care centers was constructed,incorporating subjective evaluation,objective evaluation,and comparative analysis.

Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Average Path Length of China Aviation Network Based on Complex Network

In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the node average path length of China aviation network in 1988,1994,2001,2008 and 2015 was calculated.Through regression analysis,it was found that the node degree had a logarithmic relationship with the average length of node path,and the two parameters of the logarithmic relationship had linear evolutionary trace.Key word:China aviation network,complex network,node degree,average length of node path,logarithmic relationship,evolutionary trace.

Standardization of exercise intensity and consideration of a dose-response is essential.Commentary on "Exercise-linked FNDC5/irisin rescues synaptic plasticity and memory defects in Alzheimer’s models”,by Lourenco et al.,published 2019 in Nature Medicine

Over the past decade,several biochemical pathways have been investigated to understand the underlying mechanisms involved in the beneficial effects of physical exercise on cognition.1,2 Lourenco et al.,3 in an elegant study published in Nature Medicine,examined the relationship between exercise training and hippocampal memory function.Mechanistically,the authors showed that FNDC5/irisin is an important mediator of beneficial effects of physical exercise in a mouse model of Alzheimer's disease.

Serum Ferritin and the Risk of Metabolic Syndrome:A Systematic Review and Dose-Response Meta-Analysis of Cross-sectional Studies

Objective This study aims to assess the dose-response relationship between serum ferritin(SF)and metabolic syndrome(MetS)in the two sexes.Methods We searched for articles on PubMed,the Cochrane Library,EMBASE,and the Web of Science databases that were published from 1950 to 2020.The summary odds ratio(OR)and 95%confidence interval(CI)of the association between SF and MetS were estimated using a random-effects model through a meta-analysis.Based on the methods described by Greenland and Longnecker,we explored the dose-response relationship between the two sexes.Results This study included 14 studies and 74,710 samples.The results of the classical meta-analysis showed that SF was positively associated with MetS(OR=1.77,95%CI:1.59–1.98).Regarding the components of MetS(8 studies included),the results showed that SF was positively associated with abdominal obesity(OR=1.42,95%CI:1.24–1.62),elevated fasting plasma glucose(OR=1.84,95%CI:1.50–2.25),elevated blood pressure(OR=1.17,95%CI:1.08–1.26),elevated triglycerides(OR=2.09,95%CI:1.72–2.54),and reduced high-density lipoprotein cholesterol(OR=1.33,95%CI:1.19–1.49).In the linear dose-response meta-analysis,the ORs of males,females,and postmenopausal females were 1.14(95%CI:1.13–1.16),1.32(95%CI:1.26–1.39),and 1.34(95%CI:1.22–1.47),respectively.Conclusions Our study shows that SF is significantly and positively associated with MetS,and the risk in the male population is higher than that in the female population.This finding also supports the recommendation of using SF as an early warning marker of MetS.

Interpreting Dose-Response Relation for Exposure to Multiple Sound Impulses in the Framework of Immunity

Hearing loss is a common military health problem and it is closely related to exposures to impulse noises from blast explosions and weapon firings. In a study based on test data of chinchillas and scaled to humans (Military Medicine, 181: 59-69), an empirical injury model was constructed for exposure to multiple sound impulses of equal intensity. Building upon the empirical injury model, we conduct a mathematical study of the hearing loss injury caused by multiple impulses of non-uniform intensities. We adopt the theoretical framework of viewing individual sound exposures as separate injury causing events, and in that framework, we examine synergy for causing injury (fatigue) or negative synergy (immunity) or independence among a sequence of doses. Starting with the empirical logistic dose-response relation and the empirical dose combination rule, we show that for causing injury, a sequence of sound exposure events are not independent of each other. The phenomenological effect of a preceding event on the subsequent event is always immunity. We extend the empirical dose combination rule, which is applicable only in the case of homogeneous impulses of equal intensity, to accommodate the general case of multiple heterogeneous sound exposures with non-uniform intensities. In addition to studying and extending the empirical dose combination rule, we also explore the dose combination rule for the hypothetical case of independent events, and compare it with the empirical one. We measure the effect of immunity quantitatively using the immunity factor defined as the percentage of decrease in injury probability attributed to the sound exposure in the preceding event. Our main findings on the immunity factor are: 1) the immunity factor is primarily a function of the difference in SELA (A- weighted sound exposure level) between the two sound exposure events;it is virtually independent of the magnitude of the two SELA values as long as the difference is fixed;2) the immunity factor increases monotonically from 0 to 100% as the first dose is varied from being significantly below the second dose, to being moderately above the second dose. The extended dose-response formulation developed in this study provides a theoretical framework for assessing the injury risk in realistic situations.

Atrial fibrillation burden and the risk of stroke:A systematic review and dose-response meta-analysis

BACKGROUND The increased stroke risk associated with atrial fibrillation(AF)burden exceeding 5 min is a matter of debate.In addition,the potential linear or nonlinear relationship between AF burden and stroke risk has been largely unexplored.AIM To determine the association between AF burden>5 min and the increased risk of stroke and explore the potential dose-response relationship between these two factors.METHODS Sixteen studies from six databases with 53141 subjects(mean age 65 years)were included.Fifteen studies were observational studies,and one was a randomized controlled trial study.The potential nonlinear dose-response association was characterized using a restricted cubic splines regression model.AF burden for each 1 h and 2 h was associated with an increased risk of stroke.Trial sequential analysis with a random-effect model was used to evaluate the robustness of the evidence from the included 16 studies.RESULTS AF burden>5 min was associated with an increased risk of clinical AF[adjusted risk ratio(RR)=4.18,95%confidence interval(CI):2.26-7.74].However,no association was found with an increased risk of all-cause mortality(adjusted RR=1.55,95%CI:0.87-2.75).Patients with AF burden>5 min had an increased risk of stroke(adjusted RR=2.49,95%CI:1.79-3.47).Moreover,a dose-response analysis showed that the increased stroke risk was paralleled by an increase in AF burden at a rate of 2.0%per hour(Pnonlinear=0.656,RR=1.02,95%CI:1.01-1.03).Trial sequential analysis provided robust evidence of the association between AF burden>5 min and an increased risk of stroke.CONCLUSION AF burden was a significant risk factor for clinical AF and future stroke.A significant linear association was documented between increased AF burden and risk of future stroke.

Finite Mixture Normal Models, with Application to Dose-Response Studies

In this paper, we consider the risk assessment problem under multi-levels and multiple mixture subpopulations. Our result is the generalization of the results of [1-5].1 Finite Mixture Normal ModelsIn dose-response studies, a class of phenomena that frequently occur are that experimental subjects (e.g., mice) may have different responses like ’none, mild, severe’ after a toxicant experiment, or ’getting worse, no change, getting better’ after a medical treatment, etc. These phenomena have attracted the attention of many researchers in recent years. Finite

Generalized Estimating Equations for Repeated Measures Logistic Regression in Mosquito Dose-Response

Dose-response studies in arthropod research usually involve observing and collecting successive information at different times on the same group of insects exposed to different concentrations of stimulus. When the same measure is collected repeatedly over time, the data become correlated and Probit Analysis technique which is the standard method in analyzing bioassay experiments data cannot be used. Lethal time is estimated when the speed of kill is of interest since mortality varies over time. We evaluate a complementary approach, repeated measures logistic regression using Generalized Estimating Equations (GEE), for lethal time determination in mosquito dose response. Mortality data from anopheles larva exposed to 3 botanical extracts (B,C,E) at 4 concentration levels: 500 mg/ml, 250 mg/ml, 50 mg/ml and 12.5 mg/ml were used. The result shows the estimated LT50 values with concentration 500 mg/ml being the most virulent chemical for extract B (LT50 = 10.3 hrs), C (LT50 = 7.2 hrs) and E (LT50 = 10.3 hrs). The least virulent chemical was concentration 12.5 mg/ml for extract B (LT50 = 52.1 hrs), C (LT50 = 70.7 hrs) and E (LT50 = 55.0 hrs). We conclude that repeated measures of logistic regression via GEE can be used as a tool to estimate LT50 more effectively in repeated measures of arthropod data.