Instruct: Identify the main category of the given Medrxiv paper based on its title.
Query: Reliable estimation of SARS-CoV-2 anti-spike protein IgG titers from single dilution optical density values in serologic surveys
SARS-CoV-2-specific Humoral Immune Responses after A Single Dose of Inactivated Whole-virus SARS-CoV-2 Vaccine in Kidney Transplant Recipients: An Initial Report
Clonality and timing of relapsing colorectal cancer metastasis revealed through whole-genome single-cell sequencing
Integrated Bile Acid Profile Analysis for The Non-invasive Staging Diagnosis of Ulcerative Colitis
Occupation as a risk factor for progression of chronic kidney disease: retrospective cohort study
Outbreak of P.3 (Theta) SARS-CoV-2 emerging variant of concern among food service workers in Louisiana
Vaccinating children against COVID-19: commentary and mathematical modelling
Vaccine effectiveness when combining the ChAdOx1 vaccine as the first dose with an mRNA COVID-19 vaccine as the second dose
Association of HIV with COVID-19 Outcomes Among Hospitalized Adults
Frequent Cocaine Use is Associated with Larger HIV Latent Reservoir Size
COVID-19 Bimodal Clinical and Pathological Phenotypes
A very simple model to account for the rapid rise of the British variant of SARS-CoV-2 in several countries and the world
Patient-Level Clinical Expertise Enhances Prostate Cancer Recurrence Predictions with Machine Learning
The U.S. COVID-19 Trends and Impact Survey, 2020-2021: Continuous real-time measurement of COVID-19 symptoms, risks, protective behaviors, testing and vaccination
First-generation clinical dual-source photon-counting CT: ultra-low dose quantitative spectral imaging
Prospective comparison of Bayesian and frequentist adaptive clinical trials : The SHADOW - SHINE project
Soluble angiotensin-converting enzyme 2 is transiently elevated in COVID-19 and correlates with specific inflammatory and endothelial markers
Exposure to per- and polyfluoroalkyl substances associates with altered lipid profile of breast milk
Analysis of COVID-19 case numbers: adjustment for diagnostic misclassification on the example of German case reporting data
Double burden of malnutrition and its social disparities among rural Sri Lankan adolescents
Evidence for lower threshold for diagnosis of hypertension: inferences from an urban-slum cohort in India
Vegetable intake and cardiovascular risk: genetic evidence from Mendelian randomization
Multi-state network meta-analysis of cause-specific survival data
The global distribution of COVID-19 vaccine: The role of macro-socioeconomics measures
Expression of Exosome Biogenesis Genes is Pervasively Altered by Aging in the Mouse and in the Human Brain During Alzheimer's Disease
Existence of SARS-CoV-2 RNA on ambient particulate matter samples: A nationwide study in Turkey