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A power calculation for a study with a quantitative outcome requires information on the outcome distribution under the alternative hypothesis. Researchers face challenges when they concisely specify alternative distributions in genetic studies because power depends on genotype frequencies and the average effect of each genotype. In GWAS, investigators evaluate hundreds of thousands of associations; therefore it is unrealistic to specify gene frequencies and gene effects for each test and some simplification is needed. Software packages are available to calculate power, but many of them have limited flexibility and / or may have a steep learning curve. In this review, we describe to researchers and graduate students the essentials of a power calculation for testing for an association between a quantitative trait and genotypes. In addition, we provide them with the codes of the different available software packages-free and commercial-to calculate this power. The calculations can be carried out using virtually any computer language that computes the cumulative distribution function of a non-central F-distribution.
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http://dx.doi.org/10.20897/ejeph/3925 | DOI Listing |
J Phys Chem Lett
September 2025
Materials Genome Institute, School of Materials and Energy, Yunnan University, Kunming 650091, P. R. China.
Magnetic two-dimensional van der Waals (vdWs) materials hold potential applications in low-power and high-speed spintronic devices due to their degrees of freedom such as valley and spin. In this Letter, we propose a mechanism that uses stacking engineering to control valley polarization (VP), ferroelectricity, layer polarization (LP), and magnetism in vdWs bilayers. Through first-principles calculations, we predict that the T-VSI monolayer is a magnetic semiconductor with a sizable VP.
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September 2025
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China.
Quasi-1D van der Waals materials have emerged as promising candidates for flexible electronic and thermoelectric applications due to their intrinsic anisotropy, narrow band gaps, and mechanical flexibility. Herein, MXSe (M = Nb, Ta, X = Pd, Pt) nanowires are studied to understand the bonding-directed growth mechanism. Bond valence sums and binding energy analyses reveal that weak X2-Se2 interactions perpendicular to the c-axis facilitate anisotropic growth.
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September 2025
School of Mechanical Engineering, Yonsei University, 50, Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
Core-shell electrodes provide a potential and innovative approach for significantly enhancing the performance and capacity of supercapacitors (SCs) by combining two distinct materials. The capabilities of these advanced electrodes surpass those of conventional single electrodes. Specifically, these exhibit better energy storage, higher power density, and improved overall performance.
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September 2025
Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing, 100875, China.
This study presents a novel carbazole derivative functionalized with hydroxy diphosphonic acid groups (HDPACz) as an efficient annealing-free hole transport layer (HTL) through strong bidentate anchoring to indium tin oxide (ITO). Compared to conventional mono-phosphonic acid counterparts, HDPACz demonstrates superior ITO surface coverage and interfacial dipole, effectively modulating the work function of ITO. Theoretical calculations reveal enhanced adsorption energy (-3.
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August 2025
Department of Paediatrics, All India Institute of Medical Sciences, Raebareli, Raebareli, IND.
Introduction: Early recognition of pediatric sepsis is crucial for timely intervention, prevention of mortality, and improving long-term outcomes in children. However, the lack of advanced diagnostics in resource-limited settings poses a significant challenge to early diagnosis and intervention. Complete blood count (CBC) parameters are routinely performed, cost-effective, and readily available, yet their diagnostic utility in pediatric sepsis remains underutilized.
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