The correlation factor model is developed in which the spherically averaged exchange-correlation hole of Kohn-Sham theory is factorized into an exchange hole model and a correlation factor. The exchange hole model reproduces the exact exchange energy per particle. The correlation factor is constructed in such a manner that the exchange-correlation energy correctly reduces to exact exchange in the high density and rapidly varying limits. Four different correlation factor models are presented which satisfy varying sets of physical constraints. Three models are free from empirical adjustments to experimental data, while one correlation factor model draws on one empirical parameter. The correlation factor models are derived in detail and the resulting exchange-correlation holes are analyzed. Furthermore, the exchange-correlation energies obtained from the correlation factor models are employed to calculate total energies, atomization energies, and barrier heights. It is shown that accurate, non-empirical functionals can be constructed building on exact exchange. Avenues for further improvements are outlined as well.
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http://dx.doi.org/10.1063/1.4932074 | DOI Listing |
BMC Med
December 2024
Department of Primary and Community Care, Radboud University Medical Centre, Radboud Institute for Health Sciences, Geert Grooteplein 10, Nijmegen, 6500HB, the Netherlands.
Background: Palliative sedation involves the intentional proportional lowering of the level of consciousness in patients with life-limiting disease who are experiencing refractory suffering. The efficacy of palliative sedation needs to be monitored to ensure patient comfort. The aim of this study was to evaluate the efficacy using discomfort levels combined with sedation/agitation levels.
View Article and Find Full Text PDFJ Transl Med
December 2024
Tongji Medical College, Maternal and Child Health Hospital of Hubei Province, Huazhong University of Science and Technology, Wuhan, Hubei Province, 430070, China.
Background: As a prevalent and deadly malignant tumor, the treatment outcomes for late-stage patients with cervical squamous cell carcinoma (CSCC) are often suboptimal. Previous studies have shown that tumor progression is closely related with tumor metabolism and microenvironment reshaping, with disruptions in energy metabolism playing a critical role in this process. To delve deeper into the understanding of CSCC development, our research focused on analyzing the tumor microenvironment and metabolic characteristics across different regions of tumor tissue.
View Article and Find Full Text PDFBMC Endocr Disord
December 2024
Basic and Clinical Immunology, Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal.
Background: Hashimoto's thyroiditis (HT) is associated with high cardiovascular risk. Thyroid volume has a notable dispersion of values in these patients. This study aims to clarify the association between thyroid antibodies, thyroid morphology, insulin resistance, and lipid profile in patients with HT.
View Article and Find Full Text PDFBMC Oral Health
December 2024
Department of Surgery, Program Director Orthodontics Residency Program, Section of Dentistry, The Aga Khan University Hospital, Stadium Road, P.O Box 3500, Karachi, 74800, Pakistan.
Background: Orthodontic treatment involves manipulation of tooth position that can temporarily lead to occlusal interferences capable of inducing bruxism. The objectives of this study were to determine the self-reported incidence of bruxism and its association with factors such as facial type, divergence, skeletal and dental malocclusions in orthodontic patients.
Materials And Methods: 80 patients who underwent a minimum of six months of orthodontic treatment were surveyed using a validated self-reported bruxism questionnaire for the presence or absence of bruxism.
Objective: The objective of this study was to identify serum complement factor-based biomarkers indicative of clinical efficacy in patients with first-episode schizophrenia (SCZ) following treatment with aripiprazole.
Methods: The retrospective study cohort comprised 40 patients diagnosed with first-episode SCZ (SCZ group) and 40 healthy individuals (control group). Quantitative analyses were conducted on five complement factors, namely complement component 1 (C1), C2, C3, C4, and the 50% hemolytic complement (CH50).
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