2,909 research outputs found
Blocked Cross-Validation: A Precise and Efficient Method for Hyperparameter Tuning
Hyperparameter tuning plays a crucial role in optimizing the performance of
predictive learners. Cross--validation (CV) is a widely adopted technique for
estimating the error of different hyperparameter settings. Repeated
cross-validation (RCV) has been commonly employed to reduce the variability of
CV errors. In this paper, we introduce a novel approach called blocked
cross-validation (BCV), where the repetitions are blocked with respect to both
CV partition and the random behavior of the learner. Theoretical analysis and
empirical experiments demonstrate that BCV provides more precise error
estimates compared to RCV, even with a significantly reduced number of runs. We
present extensive examples using real--world data sets to showcase the
effectiveness and efficiency of BCV in hyperparameter tuning. Our results
indicate that BCV outperforms RCV in hyperparameter tuning, achieving greater
precision with fewer computations.Comment: 28 pages, 7 figure
Disability, Physical Inactivity, and Impaired Health-Related Quality of Life Are Not Different in Metabolically Healthy vs. Unhealthy Obese Subjects
BACKGROUND:
Obesity represents a major health hazard, affecting morbidity, psychological status, physical functionality, quality of life, and mortality. The aim of the present study was to explore the differences between metabolically healthy (MHO) and metabolically unhealthy (MUO) obese subjects with regard to physical activity, disability, and health-related quality of life (HR-QoL).
METHODS:
All subjects underwent a multidimensional evaluation, encompassing the assessment of body composition, metabolic biomarkers and inflammation, physical activity level (IPAQ questionnaire), disability (TSD-OC test), and HR-QoL (SF-36 questionnaire). MHO and MUO were defined based on the absence or the presence of the metabolic syndrome, respectively.
RESULTS:
253 subjects were included (54 men and 199 women; age: 51.7 ± 12.8 vs. 50.3 ± 11.7 years, p = 0.46; BMI: 38.1 ± 5.7 vs. 38.9 ± 6.7 kg/m², p = 0.37). No significant difference was observed in body composition. There was no difference between MHO and MUO considering inflammation (hs-CRP: 6517.1 ± 11,409.9 vs. 5294.1 ± 5612.2 g/L; p = 0.37), physical inactivity (IPAQ score below 3000 METs-min/week in 77.6% of MHO vs. 80% of MUO subjects; p = 0.36), obesity-related disability (TSD-OC score > 33%, indicating a high level of obesity-related disability, in 20.2% of MHO vs. 26.5% of MUO subjects; p = 0.28), and the HR-QoL (SF-36 total score: 60 ± 20.8 vs. 62.8 ± 18.2, p = 0.27).
DISCUSSION AND CONCLUSION:The metabolic comorbidity and the impairment of functional ability and psycho-social functioning may have a different timing in the natural history of obesity. Alterations in the physical activity level and mobility disabilities may precede the onset of metabolic abnormalities. (Trial registration 2369 prot 166/12-registered 23 February 2012; Amendment 223/14-registered 13 February 2014)
Oncoplastic central quadrantectomies
Tumors localized in the central quadrant (centrally located breast tumors) have always represented a challenge for the surgeon because of the critical aesthetical matters related to the nipple-areola complex (NAC). Many years of experience with breast cancer patients treated by using various oncoplastic techniques, has allowed us to develop the modified hemibatwing for the treatment of central breast tumors, where the NAC is involved. Modified hemibatwing-along with the removal of the NAC-is a useful oncoplastic technique and it represents an ideal option for the treatment of central tumors because it assures oncological safety, a reduced surgical timetable and greater aesthetical results
Contrast-Enhanced Ultrasound: a Simple and Effective Tool in Defining a Rapid Diagnostic Work-up for Small Nodules Detected in Cirrhotic Patients during Surveillance
Disappearance of portal blood flow and arterial vascularization is the hallmark of hepatocarcinogenesis. The capability of a dynamic imaging modality detecting arterial hypervascularization of small nodules is crucial to promote a rapid diagnostic and therapeutic work-up improving survival. We aimed to evaluate the capability of CEUS to detect arterial vascularization of ≤ 2 cm HCC nodules arising during surveillance so as to shorten the diagnostic and therapeutic work-up
Reduced sleep duration affects body composition, dietary intake and quality of life in obese subjects.
Purpose Sleep duration has emerged as a crucial factor
affecting body weight and feeding behaviour. The aim of
our study was to explore the relationship among sleep
duration, body composition, dietary intake, and quality of
life (QoL) in obese subjects.
Methods Body composition was assessed by DXA.
‘‘Sensewear Armband’’ was used to evaluate sleep duration.
SF-36 questionnaire was used to evaluate quality of
life (QoL). A 3-day dietary record was administered.
Subjects were divided into 2 groups: sleep
duration[and B300 min/day.
Results 137 subjects (105 women and 32 men), age:
49.8 ± 12.4 years, BMI: 38.6 ± 6.7 kg/m2, were enrolled.
Sleep duration was B300 min in 30.6 % of subjects.
Absolute and relative fat mass (FM) (40.5 ± 9 vs.
36.5 ± 9.1 kg; 40.2 ± 4.7 vs. 36.9 ± 5.6 %), and truncal
fat mass (19.2 ± 6.1 vs. 16.6 ± 5 kg; 38.6 ± 5.3 vs.
35.2 ± 5.5 %) were higher in subjects sleeping B300 min
when compared to their counterparts (all p.05),
whereas just a tendency towards a higher BMI was
observed (p = 0.077). Even though energy intake was not
different between groups, subjects sleeping B300 min
reported a higher carbohydrate consumption per day
(51.8 ± 5.1 vs. 48.4 ± 9.2 %, p = 0.038). SF-36 total
score was lower in subjects sleeping B300 min
(34.2 ± 17.8 vs. 41.4 ± 12.9, p = 0.025). Sleep duration
was negatively associated with FM (r = -0.25, p = 0.01)
and SF-36 total score (r = -0.31, p.001). The inverse
association between sleep duration and SF-36 total score
was confirmed by the regression analysis after adjustment
for BMI and fat mass (R = 0.43, R2 = 0.19, p = 0.012).
Conclusion Reduced sleep duration negatively influences
body composition, macronutrient intake, and QoL in obese
subjects
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