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Cavity Dimensions (cavity + dimension)
Selected AbstractsChanges in Nasal Cavity Dimensions in Children and Adults by Gender and Age,THE LARYNGOSCOPE, Issue 8 2007Boles, aw K. Samoli, ski MD Abstract Objective: The aim of the study was to establish the dynamics of changes in the intranasal spaces of children and adults by gender and age. Materials and methods: Each side of the nasal cavity was evaluated separately in 366 healthy subjects 9 to 74 years old. The following acoustic rhinometry parameters were analyzed: 1) I-C, distance between the isthmus nasi (I) and the head of the inferior turbinate (C); 2) CA-I, cross-sectional area at the isthmus nasi; 3) CA-C, at the head of the inferior turbinate; and 4) CA-F, the highest point on the rhinometric curve between points I and C. Results: Before age 11 years, the intranasal spaces were slightly larger in girls than in boys. After age 11 years the nasal parameters were larger in boys than in girls. The growth rates before age 17 years were as follows: I-C: 0.073 cm/yr, 0.135 cm/yr, CA-F: 0.055 cm2/yr, 0.133 cm2/yr (P < .00001), and CA-C: 0.010 cm2/yr, 0.034 cm2/yr (P < .02) in girls and boys, respectively. In subjects older than 16 years, the mean values of I-C were 1.707 cm, 1.934 cm (P < .0001), and of CA-C, 0.493 cm2, 0.611 cm2 (P < .0001) in women and men, respectively, and changed slightly over the year. Conclusions: The parameters of intranasal spaces depend on age and gender. The dynamics of the changes is greater in boys than in girls and usually the growth is completed by the age of 16. After this age, nasal cavities are bigger in men than in women. [source] Impact of Body Mass Index on Markers of Left Ventricular Thickness and Mass Calculation: Results of a Pilot AnalysisECHOCARDIOGRAPHY, Issue 3 2005Ranjini Krishnan M.D. Specific correlations between body mass index (BMI) and left ventricular (LV) thickness have been conflicting. Accordingly, we investigated if a particular correlation exists between BMI and echocardiographic markers of ventricular function. Methods: A total of 122 patients, referred for routine transthoracic echocardiography, were included in this prospective pilot study using a 3:1 randomization approach. Patient demographics were obtained using a questionnaire. Results: Group I consisted of 80 obese (BMI was >30 kg/m2), Group II of 16 overweight (BMI between 26 and 29 kg/m2), and Group III of 26 normal BMI (BMI < 25 kg/m2) individuals. No difference was found in left ventricular wall thickness, LV end-systolic cavity dimension, fractional shortening (FS), or pulmonary artery systolic pressure (PASP) among the groups. However, mean LV end-diastolic cavity dimension was greater in Group I (5.0 ± 0.9 cm) than Group II (4.6 ± 0.8 cm) or Group III (4.4 ± 0.9 cm; P < 0.006). LV mass indexed to height2.7 was also significantly larger in Group I (61 ± 21) when compared to Group III (48 ± 19; P < 0.001). Finally, left atrial diameter (4.3 ± 0.7 cm) was also larger (3.8 ± 0.6 and 3.6 ± 0.7, respectively; P < 0.00001).Discussion: We found no correlation between BMI and LV wall thickness, FS, or PASP despite the high prevalence of diabetes and hypertension in obese individuals. However, obese individuals had an increased LV end-diastolic cavity dimension, LV mass/height2.7, and left atrial diameter. These findings could represent early markers in the sequence of cardiac events occurring with obesity. A larger prospective study is needed to further define the sequence of cardiac abnormalities occurring with increasing BMI. [source] Macrocyclic vs. dendrimeric effect.JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 10 2004A DFT study Abstract Macrocycles up to 15 members with different heteroatoms (N, O, and S) and dendrimeric functionalized branches were assembled, resulting in unique "collective" supramolecular hosts with several active sites for transition metal ions complexation. The nature of the interactions between these kinds of systems and metal ions of the first transition series (Fe, Ni, Cu, Zn) was evaluated by calculations of the binding energies at the B3LYP/LACVP* level of theory, resulting in a preference of metal ions for macrocyclic cavity in terms of complexation; however, there is a favorable contribution in energy due to the cooperative effect of dendrimeric branches (DBs) in the inclusion process by means of long-range interactions between metal ions and the heteroatoms present in DBs. According to calculated binding energies, even when the complexation in the middle of DBs appears as a less favored situation, still competes with the complexation occurred in several known macrocycles traditionally used in the formation of inclusion complexes. The capability of macrocycles as host entities is related to some criteria like: (1) the compatibility in orbital symmetry between host and guest molecules; (2) the cavity dimensions and the negative charge inside; and (3) the hardness,softness affinity between host and guest molecules. When DBs are included in host systems, their flexibility seems to be very important, in addition to localized negative charge, which permits the occurrence of long-range interactions. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1215,1226, 2004 [source] Layer-by-Layer Assembled Nanotubes as Biomimetic Nanoreactors for Calcium Carbonate DepositionMACROMOLECULAR RAPID COMMUNICATIONS, Issue 18 2009Qiang He Abstract Enzyme-loaded magnetic polyelectrolyte multilayer nanotubes prepared by layer-by-layer assembly combined with the porous template could be used as biomimetic nanoreactors. It is demonstrated that calcium carbonate can be biomimetically synthesized inside the cavities of the polyelectrolyte nanotubes by the catalysis of urease, and the size of the calcium carbonate precipitates was controlled by the cavity dimensions. The metastable structure of the calcium carbonate precipitates inside the nanotubes was protected by the outer shell of the polyelectrolyte multilayers. These features may allow polyelectrolyte nanotubes to be applied in the fields of nanomaterials synthesis, controlled release, and drug delivery. [source] Positron Annihilation Lifetimes in Cucurbiturils: Evidence of Internal Inclusion of Gold in CB[7]CHEMPHYSCHEM, Issue 5 2009Pedro Montes-Navajas Abstract Positron lifetime spectroscopy serves to determine the void volumes of cucurbituril (CB) capsules, which are not amenable to standard gas adsorption methods. In the case of the host,guest complex Au§CB[7], it also provides evidence of the inclusion of gold nanoparticles in the CB cavity (see space-filling model; Au golden, C gray, H cyan, N blue, O red). Positron annihilation lifetime (PAL) measurements are carried out to determine the cavity dimensions of hydrated and dehydrated cucurbiturils (CB[n]; n=5,6,7,8). In the case of hydrated samples, the dimensions of the cavity are unrelated to the number of glycoluril units of the CB, whereas for dehydrated samples the cavity dimensions measured by PAL follow the expected order, although the experimental values obtained by PAL are significantly smaller than the dimensions of each CB determined by crystallography. For a host,guest complex in which colloidal gold nanoparticles are assumed to be included inside CB[7], a significant reduction of the cavity size is measured. This represents an experimental evidence of the inclusion of gold inside CB[7], which complements previous high-resolution transmission electron microscopy (TEM) images. [source] Synthesis, Crystal Structures and Photoluminescence Properties of Two 2D Coordination Polymer Compounds with Drug Ligand EnoxacinCHINESE JOURNAL OF CHEMISTRY, Issue 7 2006Liang-Cai Yu Abstract Two new 2D coordination polymers of [M(Enox)2]·C2H5OH (MZn, 1 and Co, 2; HEnox=1,4-dihydro- 1-ethyl-6-fluoro-4-oxo-7-piperazine-1,8-naphtyridine-3-carboxylic acid) were synthesized under hydrothermal conditions. The single crystal X-ray diffraction analyses showed that 1 and 2 are isostructural. The Zn(II) in 1 and Co(II) ions in 2 are six-coordinated in an octahedral environment with an equatorial plane composed of four oxygen atoms:two of them from the 4-oxo and the other two from 3-carboxylate of two coordinated Enox ligands, forming a stable six-membered chelating ring with the apical positions occupied by two N atoms of the piperazinyl rings. Thus, the molecules were self-assembled into a 2D neutral square grid with cavity dimensions of 1.3399 nm×1.3399 nm for 1 and 1.3389 nm×1.3389 nm for 2, respectively. Compound 1 emits strong blue fluorescence on irradiation by UV light in the solid state at room temperature. [source] Circulating IGF-I levels are associated with increased biventricular contractility in top-level rowersCLINICAL ENDOCRINOLOGY, Issue 2 2008Giovanni Vitale Summary Background, The intensive physical activity is often associated with cardiac changes. Objectives, (i) To evaluate the IGF-I system and myocardial structure and function by standard Doppler echocardiography and Tissue Doppler in athletes and sedentary controls; and (ii) to determine any relationship between IGF-I system and echocardiographic parameters. Methods, Nineteen male top-level rowers and 19 age-matched healthy sedentary male controls underwent blood determination of fasting serum IGF-I, IGFBP-3 and acid-labile subunit levels and standard Doppler echocardiography combined with pulsed Tissue Doppler of posterior septal wall, left ventricular (LV) lateral mitral annulus and right ventricular (RV) tricuspid annulus. Myocardial presystolic (PSm), systolic (Sm), the ratio of early diastolic (Em) to atrial (Am) velocities as well as myocardial time intervals were calculated. Results, Rowers had higher serum IGF-I levels (P = 0·04), higher biventricular cavity dimensions and wall thicknesses compared to controls. They also had better LV and RV myocardial function than controls. In the rowers, IGF-I was associated with LV ejection fraction (r = 0·50, P = 0·03), RV PSm velocity (r = 0·55, P = 0·01) and with RV myocardial precontraction time (r = ,0·57, P = 0·01). These associations remained significant after adjusting for age and heart rate. Conclusions, Top-level athletes showed higher IGF-I levels and a better myocardial performance than controls, particularly for the RV systolic activity. The independent correlations between IGF-I and systolic parameters of the left (ejection fraction) and right (PSm velocity and precontraction time) ventricles may possibly indicate a role of IGF-I system in the modulation of myocardial inotropism in athletes. Further studies are needed to confirm this hypothesis. [source] | |||||||||||||