Instruct: Identify the main category of the given Medrxiv paper based on its title.
Query: Studying the course of Covid-19 by a recursive delay approach
SARS-CoV-2 variants of concern, Gamma (P.1) and Delta (B.1.617), sensitive detection and quantification in wastewater employing direct RT-qPCR
Are psychiatric disorders risk factors for COVID-19 susceptibility and severity? a two-sample, bidirectional, univariable and multivariable Mendelian Randomization study
Association between sexual and reproductive health knowledge and protective sexual behaviors among young women in Nigeria
Unravelling the link between sleep and mental health during the COVID-19 pandemic
Possible Role of P-selectin Adhesion in Long-COVID: A Comparative Analysis of a Long-COVID Case Versus an Asymptomatic Post-COVID Case
Simulated Diagnostic Performance of Ultra-Low-Field MRI: Harnessing Open-Access Datasets to Evaluate Novel Devices
The impact of malaria-protective red blood cell polymorphisms on parasite biomass in children with severe Plasmodium falciparum malaria
Humoral and T-cell immune response after three doses of mRNA SARS-CoV-2 vaccines in fragile patients: the Italian VAX4FRAIL study
Distorted TCR repertoires define multisystem inflammatory syndrome in children
Perceived racial discrimination and eating habits: Systematic review and conceptual models
Public engagement and crowdfunding for health research: A global qualitative evidence synthesis and TDR pilot
Immune responses after twofold SARS-CoV-2 immunisation in elderly residents and Health Care Workers in nursing homes and homes with assisted living support - Proposal for a correlate of protection
The impact of the coronavirus disease 2019 (COVID-19) pandemic on university students' dietary intake, physical activity, and sedentary behaviour
Understanding the comorbidity between posttraumatic stress severity and coronary artery disease using genome-wide information and electronic health records
Entitled to Property: Inheritance Laws, Female Bargaining Power, and Child Health in India
Demographic and Hygienic Factors as Predictors of Face Mask Wearing During Covid-19 Pandemic in Malaysia
Effects of COVID-19 on the human central olfactory system: a natural pre-post experiment
Deaths from cardiovascular disease involving anticoagulants: a systematic synthesis of coroners' case reports to prevent future deaths
Changes in the quality of cancer care as assessed through performance indicators during the first wave of the COVID-19 pandemic in 2020: a Scoping Review
A Progeroid Syndrome Caused by RAF1 deficiency Underscores the importance of RTK signaling for Human Development
Ageing and Dementia: Age-Period-Cohort Effects of Policy Intervention in England, 2006-2016
Hematopoietic and Lung Platelet Biogenesis as a Prognostic Indicator in Idiopathic Pulmonary Fibrosis (IPF)
Fallow time determination in dentistry using aerosol measurement.
Long COVID: Assessment of Neuropsychiatric Symptoms in Children and Adolescents - A Clinical Data Analysis
Telehealth in Rheumatology: The 2021 Arab League of Rheumatology Best Practice Guidelines