Approximate Global Alignment of Sequences

2006 ◽  
Author(s):  
T. Kahveci ◽  
V. Ramaswamy ◽  
Han Tao ◽  
Tao Li
Keyword(s):  
Global Alignment

Observing the relaxation of molecular orientation in sheared liquid crystalline polymer solutions

1990 ◽  
Vol 48 (4) ◽  
pp. 1092-1093
Author(s):  
Wendy Putnam ◽  
Christopher Viney
Keyword(s):  
Molecular Orientation ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Polymer Processing ◽  
Molecular Alignment ◽  
Global Alignment ◽  
Shear Direction ◽  
Axial Strength ◽  
Strength And Stiffness

Liquid crystalline polymers (solutions or melts) can be spun into fibers and films that have a higher axial strength and stiffness than conventionally processed polymers. These superior properties are due to the spontaneous molecular extension and alignment that is characteristic of liquid crystalline phases. Much of the effort in processing conventional polymers goes into extending and aligning the chains, while, in liquid crystalline polymer processing, the primary microstructural rearrangement involves converting local molecular alignment into global molecular alignment. Unfortunately, the global alignment introduced by processing relaxes quickly upon cessation of shear, and the molecular orientation develops a periodic misalignment relative to the shear direction. The axial strength and stiffness are reduced by this relaxation.Clearly there is a need to solidify the liquid crystalline state (i.e. remove heat or solvent) before significant relaxation occurs. Several researchers have observed this relaxation, mainly in solutions of hydroxypropyl cellulose (HPC) because they are lyotropic under ambient conditions.

scholarly journals Allograft Subsidence Decreases Postoperative Segmental Lordosis With Minimal Effect on Global Alignment Following ACDF

2021 ◽  
pp. 219256822098827
Author(s):  
Zachariah W. Pinter ◽  
Anthony Mikula ◽  
Matthew Shirley ◽  
Ashley Xiong ◽  
Scott Wagner ◽  
...  
Keyword(s):  
Global Alignment ◽  
Minimal Effect ◽  
Cervical Alignment ◽  
Entire Cohort ◽  
Patient Reported ◽  
Cage Subsidence ◽  
Student’S T ◽  
Segmental Lordosis ◽  
The Impact

Study Design: Retrospective cohort study. Objective: Studies investigating the impact of interbody subsidence in ACDF suggest a correlation between subsidence and worse radiographic and patient-reported outcomes. The purpose of this study was to assess whether allograft subsidence assessed on CT is associated with worse cervical alignment. Methods: We performed a retrospective review of a prospective cohort of patients undergoing 1 to 3 level ACDF. Cervical alignment was assessed on standing radiographs performed preoperatively, less than 2 months postoperatively, and greater than 6 months postoperatively. Allograft subsidence was assessed on CT scan performed at least 6 months postoperatively. Patients with at least 1 level demonstrating greater than 4mm of cage subsidence were classified as severe subsidence. Student’s t-test was used to compare all means between groups. Results: We identified 66 patients for inclusion, including 56 patients with non-severe subsidence and 10 patients with severe subsidence. For the entire cohort, there was a significant increase in C2-7 Lordosis (p = 0.005) and Segmental Lordosis (p < 0.00 001) from preoperative to early postoperative. On comparison of severely and non-severely subsided levels, severely subsided levels demonstrated a significantly greater loss of segmental lordosis from early to mid-term follow-up than non-severely subsided levels (-4.89 versus -2.59 degrees, p < 0.0001), manifesting as a significantly lower segmental lordosis at >6 months postoperative (0.54 versus 3.82 degrees, p < 0.00 001). There were no significant differences in global cervical alignment parameters between patients with severe and non-severe subsidence. Conclusions: Severe subsidence is associated with a significant increase in loss of segmental lordosis, but has minimal effect on global cervical alignment parameters.

P84. Which components of the global alignment proportionality score have the greatest impact on outcomes in adult spinal deformity corrective surgery?

2021 ◽  
Vol 21 (9) ◽  
pp. S180-S181
Author(s):  
Oscar Krol ◽  
Peter G. Passias ◽  
Virginie Lafage ◽  
Renaud Lafage ◽  
Justin S. Smith ◽  
...  
Keyword(s):  
Spinal Deformity ◽  
Adult Spinal Deformity ◽  
Global Alignment ◽  
Corrective Surgery

Should L3 be selected as the lowest instrumented vertebra in patients with Lenke type 5C adolescent idiopathic scoliosis whose lowest end vertebra is L4?

2021 ◽  
pp. 1-10
Author(s):  
Tomohiro Banno ◽  
Yu Yamato ◽  
Hiroki Oba ◽  
Tetsuro Ohba ◽  
Tomohiko Hasegawa ◽  
...  
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Curve Progression ◽  
Global Alignment ◽  
Fusion Surgery ◽  
Radiographic Outcomes ◽  
Lowest Instrumented Vertebra ◽  
Upper Instrumented Vertebra ◽  
Coronal Decompensation

OBJECTIVE L3 is most often selected as the lowest instrumented vertebra (LIV) to conserve mobile segments in fusion surgery; however, in cases with the lowest end vertebra (LEV) at L4, LIV selection as L3 could have a potential risk of correction loss and coronal decompensation. This study aimed to compare the clinical and radiographic outcomes depending on the LEV in adolescent idiopathic scoliosis (AIS) patients with Lenke type 5C curves. METHODS Data from 49 AIS patients with Lenke type 5C curves who underwent selective thoracolumbar/lumbar (TL/L) fusion to L3 as the LIV were retrospectively analyzed. The patients were classified according to their LEVs into L3 and L4 groups. In the L4 group, subanalysis was performed according to the upper instrumented vertebra (UIV) level toward the upper end vertebra (UEV and 1 level above the UEV [UEV+1] subgroups). Radiographic parameters and clinical outcomes were compared between these groups. RESULTS Among 49 patients, 32 and 17 were in the L3 and L4 groups, respectively. The L4 group showed a lower TL/L curve correction rate and a higher subjacent disc angle postoperatively than the L3 group. Although no intergroup difference was observed in coronal balance (CB), the L4 group showed a significantly higher main thoracic (MT) and TL/L curve progression during the postoperative follow-up period than the L3 group. In the L4 group, the UEV+1 subgroup showed a higher absolute value of CB at 2 years than the UEV subgroup. CONCLUSIONS In Lenke type 5C AIS patients with posterior selective TL/L fusion to L3 as the LIV, patients with their LEVs at L4 showed postoperative MT and TL/L curve progression; however, no significant differences were observed in global alignment and clinical outcome.

Global alignment taking into account the cervical spine with odontoid hip axis angle (OD-HA)

2021 ◽  
Author(s):  
Emmanuelle Ferrero ◽  
Pierre Guigui ◽  
Marc Khalifé ◽  
Robert Carlier ◽  
Antoine Feydy ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Global Alignment

scholarly journals Role of growth rate on the orientational alignment of Escherichia coli in a slit

2017 ◽  
Vol 4 (6) ◽  
pp. 170463 ◽  
Author(s):  
Julian Sheats ◽  
Bianca Sclavi ◽  
Marco Cosentino Lagomarsino ◽  
Pietro Cicuta ◽  
Kevin D. Dorfman
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Aspect Ratio ◽  
Density Fluctuations ◽  
Global Alignment ◽  
Similar Amount ◽  
Cell Area ◽  
Nematic Ordering ◽  
Side Walls

We present experimental data on the nematic alignment of Escherichia coli bacteria confined in a slit, with an emphasis on the effect of growth rate and corresponding changes in cell aspect ratio. Global alignment with the channel walls arises from the combination of local nematic ordering of nearby cells, induced by cell division and the elongated shape of the cells, and the preferential orientation of cells proximate to the side walls of the slit. Decreasing the growth rate leads to a decrease in alignment with the walls, which is attributed primarily to effects of changing cell aspect ratio rather than changes in the variance in cell area. Decreasing confinement also reduces the degree of alignment by a similar amount as a decrease in the growth rate, but the distribution of the degree of alignment differs. The onset of alignment with the channel walls is coincident with the slits reaching their steady-state occupancy and connected to the re-orientation of locally aligned regions with respect to the walls during density fluctuations.

scholarly journals miR-Explore: Predicting MicroRNA Precursors by Class Grouping and Secondary Structure Positional Alignment

2013 ◽  
Vol 7 ◽  
pp. BBI.S10758 ◽  
Author(s):  
Bram Sebastian ◽  
Samuel E. Aggrey
Keyword(s):  
Secondary Structure ◽  
Comparative Method ◽  
High Specificity ◽  
Computational Prediction ◽  
Training Data ◽  
Structure Alignment ◽  
Global Alignment ◽  
Gene Expressions ◽  
Small Noncoding Rnas ◽  
Prediction Approach

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expressions by targeting the mRNAs especially in the 3′UTR regions. The identification of miRNAs has been done by biological experiment and computational prediction. The computational prediction approach has been done using two major methods: comparative and noncomparative. The comparative method is dependent on the conservation of the miRNA sequences and secondary structure. The noncomparative method, on the other hand, does not rely on conservation. We hypothesized that each miRNA class has its own unique set of features; therefore, grouping miRNA by classes before using them as training data will improve sensitivity and specificity. The average sensitivity was 88.62% for miR-Explore, which relies on within miRNA class alignment, and 70.82% for miR-abela, which relies on global alignment. Compared with global alignment, grouping miRNA by classes yields a better sensitivity with very high specificity for pre-miRNA prediction even when a simple positional based secondary and primary structure alignment are used.

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