We investigate weighted straight skeletons from a geometric, graph-theoretical, and combinatorial point of view. We start with a thorough definition and shed light on some ambiguity issues in the procedural definition. We investigate the geometry, combinatorics, and topology of faces and the roof model, and we discuss in which cases a weighted straight skeleton is connected. Finally, we show that the weighted straight skeleton of even a simple polygon may be non-planar and may contain cycles, and we discuss under which restrictions on the weights and/or the input polygon the weighted straight skeleton still behaves similar to its unweighted counterpart. In particular, we obtain a non-procedural description and a linear-time construction algorithm for the straight skeleton of strictly convex polygons with arbitrary weights.
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http://dx.doi.org/10.1016/j.comgeo.2014.08.006 | DOI Listing |
Sci Rep
January 2025
Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China.
Germplasm resources within the Medicago genus are highly regarded for their value as forage crops and their critical roles in nitrogen cycling, ecosystem restoration, and soil structure improvement. Therefore, understanding the diversity of seed morphology in this genus is essential for advancing its development and utilization. This study analyzed seed samples from 587 germplasm accessions representing 77 species within Medicago genus, as well as 32 accessions from 21 species within the closely related genus Trigonella.
View Article and Find Full Text PDFOper Orthop Traumatol
January 2025
Klinik für Orthopädie und Unfallchirurgie, Martin-Luther-Krankenhaus Berlin, Caspar-Theyss-Str. 27-33, 14193, Berlin, Deutschland.
Objective: Lengthening of the patellar tendon to normalize patellar height and improve knee flexion deficits.
Indications: Flexion deficits in combination with patella baja (Caton index < 0.6).
Spine Deform
January 2025
Department of Orthopedic Surgery, Mayo Clinic, 200 First Street S.W, Rochester, MN, 55906, USA.
Purpose: Non-fusion surgical options for pediatric scoliosis management such as vertebral body tethering (VBT) offer an alternative to spinal fusion. With this study, we aim to evaluate the postoperative outcomes in boys versus girls who have undergone VBT. Our hypothesis is that girls and boys will have similar outcomes by 2-year follow-up.
View Article and Find Full Text PDFAppl Radiat Isot
March 2025
Tokyo City University, 1-28-1, Tamazutsumi, Setagaya-ku, Tokyo, 158-8557, Japan.
In clearance measurements involving a single material type, a conversion factor was applied to convert measurement results to activity based on an assumed uniform density. However, this factor has been found to underestimate activity in material mixtures. In this study, we proposed a method to identify the location with the lowest detection sensitivity (minimum location) in a mixture and evaluated its applicability to the conversion factor.
View Article and Find Full Text PDFJ Addict Med
November 2024
From the Center for the Study of Drugs, Alcohol, Smoking, and Health, University of Michigan, Ann Arbor, MI (EP, RJE-P, TSS, CWE, VVM, SEM); Institute for Social Research, University of Michigan, Ann Arbor, MI (RJE-P, CWE, SEM); Department of Psychology, Texas State University, San Marcos, TX (TSS); Department of Psychiatry, University of Michigan, Ann Arbor, MI (VVM); and Lighthouse Institute at Chestnut Health Systems, Eugene, OR (TKD).
Objectives: Most US treatment and recovery services are abstinence-based. However, many people in recovery from an alcohol or other drug (AOD) use problem do not abstain completely. This study estimated the prevalence of and characteristics associated with nonabstinence among US adults in recovery.
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