1. The theory of methods of hypothesis testing in relation to the detection of bimodality in density distributions is discussed. 2. Practical problems arising from these methods are outlined. 3. The power of three methods of hypothesis testing was compared using simulated data from bimodal distributions with varying separation between components. None of the methods could determine bimodality until the separation between components was 2 standard deviation units and could only do so reliably (greater than 90%) when the separation was as great as 4-6 standard deviation units. 4. The robustness of a parametric and a non-parametric method of hypothesis testing was compared using simulated unimodal distributions known to deviate markedly from normality. Both methods had a high frequency of falsely indicating bimodality with distributions where the components had markedly differing variances. 5. A further test of robustness using power transformation of data from a normal distribution showed that the algorithms could accurately determine unimodality only when the skew of the distribution was in the range 0-1.45.
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http://dx.doi.org/10.1111/j.1365-2125.1989.tb03558.x | DOI Listing |
J Ultrasound
January 2025
Argentinian Critical Care Ultrasonography Association (ASARUC), Buenos Aires, Argentina.
Hepatic gas gangrene (HGG) is a rare but life-threatening condition typically caused by anaerobic bacteria such as Clostridium perfringens, though Gram-negative bacteria like Escherichia coli and Klebsiella species have also been implicated. Traditionally diagnosed via computed tomography (CT), point-of-care ultrasound (POCUS) has emerged as a valuable tool in critical care settings for its non-invasive, bedside utility. We report the case of a 51-year-old female with choledochal syndrome secondary to cholangiocarcinoma who developed HGG following left extended hepatectomy and biliary reconstruction.
View Article and Find Full Text PDFJ Assist Reprod Genet
January 2025
UMass Memorial Medical Center, Memorial Campus, 119 Belmont St, Worcester, MA, 01605, USA.
Purpose: Induction of meiotic competence is a major goal of the controlled ovarian stimulation used in ART. Do factors intrinsic to the oocyte contribute to oocyte maturation? Deletions in mtDNA accumulate in long-lived post mitotic tissues and are found in human oocytes. If oogenesis cleanses the germline of deleterious deletions in mtDNA, meiotically competent oocytes should contain lower levels of mtDNA deletions vs.
View Article and Find Full Text PDFLupus Sci Med
January 2025
Dermatology, The University of Texas Southwestern Medical Center, Dallas, Texas, USA
Objective: Metabolic reprogramming plays a critical role in modulating the innate and adaptive immune response, but its role in cutaneous autoimmune diseases, such as cutaneous lupus erythematosus (CLE), is less well studied. An improved understanding of the metabolic pathways dysregulated in CLE may lead to novel treatment options, biomarkers and insights into disease pathogenesis. The objective was to compare metabolomic profiles in the skin and sera of CLE and control patients using liquid chromatography-mass spectrometry (LC-MS).
View Article and Find Full Text PDFMatrix Biol
January 2025
Department of Pharmacology & Immunology, Proteomics Center, Medical University of South Carolina, Charleston, SC. Electronic address:
Collagen stroma interactions within the extracellular microenvironment of breast tissue play a significant role in breast cancer, including risk, progression, and outcomes. Hydroxylation of proline (HYP) is a common post-translational modification directly linked to breast cancer survival and progression. Changes in HYP status lead to alterations in epithelial cell signaling, extracellular matrix remodeling, and immune cell recruitment.
View Article and Find Full Text PDFJ Arthroplasty
January 2025
The University of Tennessee Health Science Center-Campbell Clinic Department of Orthopaedic Surgery and Biomedical Engineering, 1400 S. Germantown Rd, Germantown, TN, 38138. Electronic address:
Background: This study investigated the influence of surgical alignment techniques on knee joint biomechanics during stair negotiation tasks. Our hypothesis was that a more personalized joint alignment would result in reduced medial knee loading biomechanics to negotiate the stairs.
Methods: There were 28 adults (14 mechanical alignments [MA], 14 kinematic alignment [KA]) who underwent total knee arthroplasty (TKA) at least one year post-operatively and performed five stair ascent and descent trials at their preferred velocities.
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