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Proper Position (proper + position)
Selected AbstractsA novel membrane specialization in the sperm tail of bug insects (heteroptera),JOURNAL OF MORPHOLOGY, Issue 7 2009David Mercati Abstract The sperm tail of bug insects has 9 + 9 + 2 flagellar axonemes and two mitochondrial derivatives showing two to three crystalline inclusions in their matrix. During spermiogenesis, the axoneme is surrounded by a membrane cistern which, at sperm maturity, reduces to two short cisterns on the opposite sides of the axoneme adhering to the mitochondrial derivatives. Filamentous bridges connect the intertubular material of the axoneme to these cisterns. Such bridges, which represent a peculiar feature of bug insects, are resistant to detergent treatment, whereas part of the intertubular material and the inner content of microtubular doublets are affected by the treatment. After freeze-fracture replicas, at the insertion of the bridges to the cisternal membrane, the P-face of this membrane shows a characteristic ribbon consisting of four rows of 11 ± 1 nm staggered intramembrane particles, 13 ± 2 nm apart along each row. The bridges could be able to maintain the axoneme in the proper position during flagellar beating avoiding distortion affecting sperm motility. J. Morphol. 2009. © 2009 Wiley-Liss, Inc. [source] A system for the diagnosis, placement, and prosthetic restoration of root form implants (U.S. Patent #5,769,636)JOURNAL OF PROSTHODONTICS, Issue 1 2003Francesco Di Sario DDS It is difficult to achieve a high degree of reproducibility when using a diagnostic wax-up as the template for fabrication of a definitive implant restoration. Here a method for implant prosthesis treatment planning is described that allows fabrication of the provisional restoration before surgical placement of the implant. The method involves 6 steps: (1) determining the mesiodistal inclination of the implant, (2) determining the buccolingual dimension of the alveolar ridge, (3) determining the proper position of the implant, (4) fabricating the surgical guide, (5) fabricating the provisional restoration, and (6) performing surgical placement of the implant followed by immediate placement of the provisional restoration. [source] Indigenous and austere technique of self-retaining abdominal retraction for facilitating surgical exposureJOURNAL OF SURGICAL ONCOLOGY, Issue 5 2006Sajid S. Qureshi MS Abstract Adequate exposure is of paramount importance in major abdominal surgeries. This is achieved by appropriately placed incision, proper position of the patients, and judicious use of retractors. A third assistant is usually required for retaining the retractors. Self-retaining retractors have also been utilized for assisting in adequate exposure of the operative field. However, these retractors are complex and unwieldy, causing hindrance in the movement of the surgeon. We describe a technique of self-retaining abdominal retraction that is simple and also obviates the need for an additional assistant. J. Surg. Oncol. 2006;93:420,421. © 2006 Wiley-Liss, Inc. [source] Descending aortic blood flow and cardiac output: A clinical and experimental study of continuous oesophageal echo-Doppler flowmetryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2001H. Odenstedt Background: Several studies have demonstrated that perioperative optimisation of oxygen delivery and haemodynamics can reduce mortality and morbidity for high-risk surgical patients. To optimise cardiac output, reliable, continuous and "less invasive" methods for measuring cardiac output are urgently needed. Methods: Eight landrace pigs were studied during experimental repeated cardiac tamponade and 14 patients during liver transplantation. Aortic blood flow was measured by using transoesophageal echo-Doppler technique. A total of 91 paired measurements of aortic blood flow and cardiac output with different techniques were performed in the pigs and 124 paired measurements in the patients. Results: Transoesophageal echo-Doppler did provide continuous real-time monitoring of the rapid and dramatic haemodynamic changes occurring during cardiac tamponade and during liver transplantation, while only intermittent information was obtained from the bolus thermodilution technique. Changes in haemodynamics were more difficult to detect with the "continual" cardiac output thermodilution technique. Changes in aortic blood flow closely followed changes in cardiac output determined by the bolus thermodilution technique both in pigs (r=0.89) and in patients (r=0.80). In patients, aortic blood flow constituted about 70% of cardiac output determined by the bolus thermodilution technique. Conclusions: A combined echo-Doppler technique can be valuable for continuous monitoring of haemodynamic changes in the perioperative setting, and changes in aortic blood flow agree well with corresponding changes in cardiac output intermittently obtained by thermodilution cardiac output measurements. With the combined echo-Doppler technique a proper position of the Doppler beam is greatly facilitated by the M-mode echo visualisation of the aortic wall and aortic cross-sectional area is continuously measured. [source] Human motion reconstruction from monocular images using genetic algorithmsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2004Jianhui Zhao Abstract This paper proposed an optimization approach for human motion recovery from the un-calibrated monocular images containing unlimited human movements. A 3D skeleton human model based on anatomy knowledge is employed with encoded biomechanical constraints for the joints. Energy Function is defined to represent the deviations between projection features and extracted image features. Reconstruction procedure is developed to adjust joints and segments of the human body into their proper positions. Genetic Algorithms are adopted to find the optimal solution effectively in the high dimensional parameter space by simultaneously considering all the parameters of the human model. The experimental results are analysed by Deviation Penalty. Copyright © 2004 John Wiley & Sons, Ltd. [source] Structure of a human telomeric DNA sequence stabilized by 8-bromoguanosine substitutions, as determined by NMR in a K+ solutionFEBS JOURNAL, Issue 14 2007Akimasa Matsugami The structure of human telomeric DNA is controversial; it depends upon the sequence contexts and the methodologies used to determine it. The solution structure in the presence of K+ is particularly interesting, but the structure is yet to be elucidated, due to possible conformational heterogeneity. Here, a unique strategy is applied to stabilize one such structure in a K+ solution by substituting guanosines with 8-bromoguanosines at proper positions. The resulting spectra are cleaner and led to determination of the structure at a high atomic resolution. This demonstrates that the application of 8-bromoguanosine is a powerful tool to overcome the difficulty of nucleic acid structure determination arising from conformational heterogeneity. The obtained structure is a mixed-parallel/antiparallel quadruplex. The structure of telomeric DNA was recently reported in another study, in which stabilization was brought about by mutation and resultant additional interactions [Luu KN, Phan AT, Kuryavyi V, Lacroix L & Patel DJ (2006) Structure of the human telomere in K+ solution: an intramolecular (3+1) G-quadruplex scaffold. J Am Chem Soc 128, 9963,9970]. The structure of the guanine tracts was similar between the two. However, a difference was seen for loops connecting guanine tracts, which may play a role in the higher order arrangement of telomeres. Our structure can be utilized to design a small molecule which stabilizes the quadruplex. This type of molecule is supposed to inhibit a telomerase and thus is expected to be a candidate anticancer drug. [source] | ||||||||||