Introduction Cone-beam computed tomography (CBCT) imaging has broadened opportunities for examining morphologic aspects of the craniofacial complex, including alveolar bone, but limitations of the ...technology have yet to be defined. Through the use of comparisons with direct measurements, the purpose of this study was to investigate the accuracy and reliability of buccal alveolar bone height and thickness measurements derived from CBCT images. Methods Twelve embalmed cadaver heads (5 female, 7 male; mean age: 77 years) were scanned with an i-CAT 17-19 unit (Imaging Sciences International, Hatfield, Pa) at 0.3 mm voxel size. Buccal alveolar bone height and thickness measurements of 65 teeth were made in standardized radiographic slices and compared with direct measurements made by dissection. All measurements were repeated 3 times by 2 independent raters and examined for intrarater and interrater reliability. Measurement means were compared with 2-tailed t tests. Agreement between direct and CBCT measurements was assessed by concordance correlation coefficients, Pearson correlation coefficients, and Bland-Altman plots. Results Intrarater reliability was high as were interrater correlations for all measurements (≥0.97) except CBCT buccal bone thickness (0.90). CBCT measurements did not differ significantly from direct measurements, and there was no pattern of underestimation or overestimation. The mean absolute differences were 0.30 mm in buccal bone height and 0.13 mm in buccal bone thickness with 95% limits of agreement of −0.77 to 0.81 mm, and −0.32 to 0.38 mm, respectively. Agreement between the 2 methods was higher for the measurements of buccal bone height than buccal bone thickness, as demonstrated by concordance correlation coefficients of 0.98 and 0.86, respectively. Conclusions For the protocol used in this study, CBCT can be used to quantitatively assess buccal bone height and buccal bone thickness with high precision and accuracy. Comparing the 2 sets of CBCT measurements, buccal bone height had greater reliability and agreement with direct measurements than did the buccal bone thickness measurements.
We obtain explicit formulas for the number of monic irreducible polynomials with prescribed constant term and degree $q_1q_2$ over a finite field, where $q_1$ and $q_2$ are distinct odd~primes. These ...formulas are derived from work done by Yucas. We show that the number of polynomials of a given constant term depends only on whether the constant term is a $q_1$-residue and/or a $q_2$-residue in the underlying field. We further show that as $k$ becomes large, the proportion of irreducible polynomials having each constant term is asymptotically equal. This paper continues work done in 1.
Mining of the EST database identified a human EST that was predicted to encode a novel member of the glycoprotein hormone receptor subfamily. Based on the sequence information, the full-length coding ...region of this gene was isolated and sequenced. This gene, designated HG38, is predicted to encode a polypeptide of 907 amino acid residues with a putative signal peptide sequence at its very N-terminus. HG38 is most closely related to members of the glycoprotein hormone receptor subfamily with ∼35% overall identity at the protein sequence level. As with the glycoprotein hormone receptors, HG38 contains a long extracellular domain with a total of 16 leucine-rich repeats. Northern blot analysis showed that HG38 was expressed in skeletal muscle, placenta, spinal cord, and various regions of the brain. Radiation hybrid mapping placed HG38 into human chromosome 12q22-23. HG38 is most likely to be a receptor for a novel class of glycoprotein ligands.
Splines with boundary conditions McDonald, Terry
Computers & mathematics with applications (1987),
11/2007, Letnik:
54, Številka:
9
Journal Article
Recenzirano
Odprti dostop
This paper explores spaces of splines satisfying boundary conditions using the long exact sequence for relative homology. We relate them to the boundary complex of
Δ
, where
Δ
is a planar simplicial ...complex which triangulates a pseudomanifold. In this case, there is a natural relationship between the Hilbert polynomials (which measure the dimension of
C
k
r
(
Δ
̂
)
for
k
≫
0
) of the spline modules.
For a
d-dimensional polyhedral complex
P, the dimension of the space of piecewise polynomial functions (splines) on
P of smoothness
r and degree
k is given, for
k sufficiently large, by a polynomial
...f
(
P
,
r
,
k
)
of degree
d. When
d
=
2
and
P is simplicial, Alfeld and Schumaker give a formula for all three coefficients of
f. However, in the polyhedral case, no formula is known. Using localization techniques and specialized dual graphs associated to codimension-2 linear spaces, we obtain the first three coefficients of
f
(
P
,
r
,
k
)
, giving a complete answer when
d
=
2
.
This investigation is a validity study on an instrument designed to assess the cognitive status of CHI patients in the acute phase. The Wolinsky Amnesia Information Test (WAIT) is a questionnaire, ...orally administered and then scored in a standardized format. Interrater reliability has been previously demonstrated. In this study, the WAIT was compared to the Galveston Orientation and Amnesia Test (GOAT), CT scans, and the Glasgow Coma Scale (GCS). Seventy-five subjects participated in the study, all hospital trauma patients at an urban regional trauma centre, who had been referred to the neuropsychology consult service for cognitive testing. Patients were screened to rule out preexisting developmental, drug, alcohol, or documented prior LOC history. Patients' ages ranged from 18-59, with a mean of 33.45 years. A large majority of the patients (81.3%) were diagnosed with a mild level of CHI. Concurrent, discriminative, and construct validity of the WAIT were investigated, and found satisfactory. The data were submitted to factor analysis in order to uncover underlying constructs. In addition to the 'orientation' and 'amnesia' factors identified through factor analysis, a third factor was found and labelled: 'personal temporal/continuum memory'. Limitations of the study and possible directions for future research are discussed.
PDF
