Survival estimation through the cumulative hazard with monotone natural cubic splines using convex optimization-the HCNS approach

2020 ◽  
Vol 190 ◽  
pp. 105357
Author(s):  
Leonidas E. Bantis ◽  
John V. Tsimikas ◽  
Stelios D. Georgiou
Animals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 197 ◽  
Author(s):  
Bethany Wilson ◽  
James Serpell ◽  
Harold Herzog ◽  
Paul McGreevy

Drawing on American Kennel Club (AKC) puppy registration numbers for approximately 82 varieties of pedigree dogs between 1926 and 2005, the current article analyses behavioural reports on 32,005 dogs of these varieties reported through the Canine Behavioural Assessment and Research Questionnaire (C-BARQ). Cluster analysis of C-BARQ scores indicates that the 82 breeds fell into six clusters. Average scores for each of the 14 behavioural subscales and 22 miscellaneous traits in C-BARQ were calculated for each cluster, and the breeds in each cluster with average scores most similar to the cluster averages were selected as titular breeds. Titular breeds for each cluster were the Maltese terrier, the Great Dane, the Akita, the Australian shepherd, the American Staffordshire terrier, and the Weimaraner. Using the AKC data, we tracked longitudinal trends in annual registration numbers of breeds of each cluster over the period from 1926 to 2005. This period was subdivided into periods with differing overall trends by fitting natural cubic splines to the overall raw trend and considering both the spline and its derivative curves. Differences in the absolute numbers of dogs and trends in registrations over nearly 80 years were identified: an Early period (1926–1944, during which total registration numbers were very low); a Mid-Century Period (1945–1971, during which total registration numbers were tending to rise from year to year); a First Decline (1972–1979, a brief period during which registration numbers experienced a trend of more gradual decline); a Recovery (1980–1992, where registration numbers began to gradually rise again); and a Second Decline (1993–2005, a second sustained period of falling registration numbers, more dramatic than the first decline). The current article describes the ways in which the clustered behaviour of dogs associate with these trends. That said, there is no compelling evidence that shifts in the popularity within or between the clusters reflect consumer canine behavioural preferences. Understanding historic trends in the demand for certain canine behavioural traits could help veterinary and urban animal management stakeholders to anticipate future needs for education and infrastructure.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Bots ◽  
N.C Onland-Moret ◽  
I.I Tulevski ◽  
G.A Somsen ◽  
H.M Den Ruijter

Abstract Background Heart failure (HF) guidelines recommend equal target doses for women and men. Recently, these recommendations have been challenged as research suggested that women with HF with reduced Ejection Fraction (HFrEF) may reach optimal treatment effect at half of the guideline-recommended dose while men may require the full dose. However, it is unclear how often women and men reach guideline-recommended target doses in daily practice. Purpose To evaluate whether women and men with HF reach guideline-recommended target doses for Angiotensin-converting enzyme inhibitors (ACEI)/angiotensin II receptor blocker (ARB), β-blockers (BB) and mineralocorticoid receptor antagonists (MRA) in daily practice. Methods We extracted data from 13 outpatient cardiology clinics for all individuals diagnosed with HF within 14 days leading up to their visit who were prescribed at least one guideline-recommended HF medication. HF was defined based on a combination of the cardiologist's diagnosis and left ventricular systolic or diastolic dysfunction determined during echocardiography. Guideline-recommended medication groups and target doses were taken from the 2016 ESC HF guidelines or from literature for medications not mentioned in the guidelines. To enable comparison between medications and medication groups, daily dose was converted to percentage of target dose. Mean change in percentage of target dose over consecutive medication prescriptions was modelled for men and women using natural cubic splines. Results We included 1254 patients with HF (48% women). Women were on average older at diagnosis (71 vs 67 years) and more often had hypertension (54.9 vs 44.3%), but less often had diabetes mellitus (13.5 vs 19.4%), a history of coronary heart disease (7.8 vs 19.6%,) or past cardiovascular interventions (8.7 vs 23.0%) than men. In total, 1069 patients were prescribed an ACEI/ARB (46% women), 920 a BB (48% women) and 243 an MRA (43% women). Women were more often prescribed only one medication than men (39.6 vs 33.2%, p=0.014). Approximately 14% of first prescriptions for all medications were at 100% of target dose or higher for both women and men, with the majority of prescriptions being either at 1–49% of target dose (47.2 vs 45.5%, respectively) or 50–99% of target dose (39.1 vs 40.8%, respectively). The natural cubic splines showed that this distribution did not change over consecutive drug prescriptions in either women or men. Only MRA prescriptions for men showed an upward trend and reached 100% of target dose. Conclusion In daily practice, both women and men were unlikely to reach guideline-recommended target doses for both ACEI/ARBs and BBs. For MRAs, women were less likely to reach target dose than men. Optimal dosing in HF is difficult for both sexes, but in light of recent evidence, the challenge in daily practice seems to lie more in undertreatment of men than overtreatment of women. Figure 1 (women in red, men in blue) Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): ZonMw


Epidemiology ◽  
2003 ◽  
Vol 14 (Supplement) ◽  
pp. S41
Author(s):  
R Kregzdyte ◽  
L Strumylaite ◽  
R Naginiene ◽  
O Abdrakhmanovas

Sensors ◽  
2009 ◽  
Vol 9 (12) ◽  
pp. 9629-9665 ◽  
Author(s):  
Won Hee Lee ◽  
Kiyun Yu

2008 ◽  
Vol 78 (2) ◽  
pp. 281-287 ◽  
Author(s):  
Seba AlHarbi ◽  
Eman A. Alkofide ◽  
Abdulaziz AlMadi

Abstract Objective: To present a comprehensive mathematical analysis of dental arch curvature in subjects with normal occlusion. Materials and Methods: The materials studied were 40 sets of upper and lower plaster dental casts of subjects presenting with normal occlusion. The sample was equally divided into casts from male and female subjects with an age range from 18 to 25 years. Curve-fitting analyses was carried out and four main categories of functions were considered: the beta function, natural cubic splines, polynomial equations, and Hermite cubic splines. Results: The polynomial function (fourth order) was found to be a reasonable analysis when the objective is to describe the general smooth curvature of the dental arch, while a Hermite cubic spline is more appropriate when it is desired to track arch irregularities, such as evaluating treatment changes. Conclusions: Due to its advantage in providing a more naturally smooth curve, the fourth-order polynomial function may be used as a guide to fabricate customized arch wires, or even an entire fixed orthodontic appliance system.


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