Abstract Internal rotation in symmetric top molecules offers an excellent opportunity to investigate large amplitude motion in a relatively simple intramolecular environment. Due to specific symmetry characteristics of a symmetric top molecular frame, the internal rotation degree of freedom is in the zeroth order approximation separable from the small amplitude vibrations and the overall rotation, thus enabling to characterize the vibrational-torsional-rotational energy structure with a relatively simple Hamiltonian. Lessons from symmetric internal rotor studies may be applied to more complex systems, such as asymmetric internal rotors and macromolecules. This thesis deals with internal rotation in CH3SiH3, CH3SiD3, CH3CF3 which have become a prototype of symmetric internal rotors. The thesis presents high resolution vibration-torsion-rotation spectra and detailed analysis of these molecules. Particular attention is focused on torsion-mediated interactions, such as Coriolis-type interactions and Fermi-type interactions, coupling the internal rotation and the small amplitude vibrational motion. The studies show that the expansion of the data to the small amplitude vibrations and inclusion of the torsion-mediated interactions play a crucial role in order to obtain an appropriate characterization of the vibrational-torsional-rotational energy level structure and physically meaningful molecular parameters.

Examinations of the effects of (a.) alkyl carbon chain length and (b.) perfluorination of acyl chlorides; propionyl chloride, butyryl chloride, valeroyl chloride, and perfluorinated acyl chlorides; perfluoropropionyl chloride and perfluorobutyryl chloride, are reported and compared using CP-FTMW spectroscopy. All of these molecules are already published in various journals except for valeroyl chloride. The chapters are organized by molecule alkyl chain length and include some background theory. Conformational stability, internal rotation, helicity, and ionic character of the C-Cl bond via the nuclear electric quadrupole coupling constant (χzz) are analyzed. Results show syn, syn-anti/syn-gauche, and syn-anti-anti/syn-gauche-anti stable conformations. Internal rotation was only seen in propionyl chloride. Helicity was not observed. (χzz) was observed to be inert to alkyl chain length, ~ 60 MHz and ~ 65 MHz for the nonfluorinated and fluorinated acyl chlorides. Partial fluorination and varying functional groups are recommended.

The infrared, Raman and ultraviolet spectra of pyridine-d0 and pyridine-d5 were recorded and assigned with a focus on the low-frequency vibrational modes in the S1(n,pi*) electronic excited state. An energy map for the low-frequency modes was constructed and the data for the v18 mode allowed a highly anharmonic one-dimensional potential energy function to be determined for the S1 excited state. In this S1(n,pi*) state, pyridine is quasi-planar and very floppy with a barrier to planarity of 3 cm^-1. The infrared, Raman and ultraviolet spectra of 2-fluoropyridine (2FPy) and 3-fluoropyridine (3FPy) have been collected and assigned. For 2FPy about 150 bands were observed for the transitions to the vibronic levels of the S(pi, pi*) state at 38,030.4 cm^-1. For 3FPy more than a hundred absorption bands associated with the S(n,pi*) state at 35,051.7 cm^-1 and about forty broad bands associated with the S(pi, pi*) state at 37,339 cm^-1 were observed. The experimental work was complemented by ab initio calculations and these also provided calculated structures for 2FPy, 3FPy, and pyridine. They showed that the fluorine atom on the ring participates in the pi bonding. The gas-phase Raman spectra of 1,3-butadiene and its 2,3-d2, 1,1,4,4-d4, and d6 isotopomers have been recorded with high sensitivity in the region below 350 cm-1, in order to investigate the internal rotation (torsional) vibration. The data for all the isotopomers were then fit using a one-dimensional potential energy function of the form V = (1/2)Sigma(Vn(1-cos (phi))). The energy difference between trans and gauche forms was determined to be about 1030 cm^-1 (2.94 kcal/mol), and the barrier between the two equivalent gauche forms to be about 180 cm^-1 (0.51 kcal/mol), which agrees well with high-level ab initio calculations. The results from an alternative set of assignments also fits the data quite well are also presented. Combination and hot band series involving the v13 torsional vibration of the trans rotamer were observed for each of the butadiene isotopomers. In addition, the high signal to noise of the Raman spectra made it possible to detect several dozen bands of the gauche rotor which makes up only about 2% of the molecules at ambient temperature.

Progressive overload through the range of motion (ROM) is important for proper rehabilitation of muscle strength, yet varies across types of resistance for a given exercise. The purpose of this study was to compare strength curves (SC) for shoulder internal (IR) and external rotation (ER) with resistance curves (RC) for two application angles (A and B) of Thera-Band® resistance to determine which application angle best overloads IR and ER through the ROM. Thirty volunteer subjects participated in this study. SCs were obtained experimentally by measuring maximal isometric torque for IR and ER from 30° to 135°. RCs were calculated using regression equations from the literature. Significant differences (p < 0.05) were found between the SCs and RCs for both application angles during IR and ER. The findings of this study indicate that application angles A and B do not provide optimal loading when performing shoulder IR and ER exercises.

No description available.

Objective: To determine the ability of the Tibial Plateau Leveling Osteotomy (TPLO) to restore normal joint kinematics in a cranial cruciate ligament (CrCL)-deficient stifle through a loaded range of motion. Methods: Paired pelvic limbs from 12 dogs were compared in an in vitro biomechanical study. Each limb was placed in a custom designed jig at 120° of stifle extension under an axial load of 20% body weight. Electromagnetic motion tracking sensors were placed on the distal femur and proximal tibia. A force was applied at approximately 10 N/sec to mimic the action of the quadriceps muscle. Force application allowed the limb to move from 120° to maximal extension. Positional data was acquired at 60 points/second. Each limb was tested under normal, CrCL-deficient, and TPLO-treated conditions. Results: The TPLO failed to normalize CTT within the CrCL-deficient stifle; however, values trended towards intact values throughout the range of motion. No significant differences were noted in internal rotation in any of the three conditions from 120° – 137°. Hyperextension values did not differ significantly between conditions. Conclusion: Data from this biomechanical model suggests that the TPLO fails to neutralize CTT throughout a loaded range of motion. Internal rotation and hyperextension values were not found to differ significantly between intact, CrCL-deficient and TPLO repaired stifles. The effectiveness of the TPLO in restoring normal biomechanics is more significant at greater angles of flexion. / Master of Science

Objective: To evaluate the relative position of the femur and tibia in cranial cruciate ligament (CCL) intact stifles, CCL deficient stifles, and stifles following a novel extracapsular procedure (lateral extracapsular suture system or LESSa) under load at specific joint angles. Study Design: In vitro biomechanical study. Methods: Twenty pelvic limbs from 11 dogs were used to evaluate the relative position of the femur and tibia between 3 stifle conditions (CCL intact, CCL deficient, and LESSa treated) at a load of 30 % and stifle angles of 125", 135", and 145" using electromagnetic tracking sensors. Results: Cranial cruciate ligament deficient stifles had significantly greater (p <0.0001) cranial displacement and internal rotation of the tibia relative to the femur than CCL intact stifles or LESSa treated stifles at all stifle angles. Cranial displacement of the tibia relative to the femur for CCL intact and LESSa treated were not significantly different from one another at stifle angles of 125", but were significantly different at stifle angles of 135" (p = 0.0182) and 145" (p = 0.0012). There was no significant difference in internal rotation of the tibia relative to the femur between CCL intact and LESSa treated stifles at any of the stifle angles. Conclusion: LESSa effectively decreases cranial tibial displacement and eliminates internal rotation of the tibia relative / Master of Science

Investigations presented here are (a) the study of reorientational dynamics and internal rotation in transition metal complexes by NMR relaxation experiments, and (b) the study of ligand exchange dynamics in transition metal complexes by exchange NMR experiments. The phenyl ring rotation in Ru3(CO)9(μ3-CO)(μ3-NPh) and Re(Co)2(CO)10(μ3- CPh) was monitored by 13C NMR relaxation experiments to probe intramolecular electronic and/or steric interactions. It was found that the rotation is relatively free in the first complex, but is restrained in the second one. The steric interactions in the complexes were ascertained by the measurement of the closest approach intramolecular distances. The rotational energy barriers in the two complexes were also calculated by using both the Extended Hiickel and Fenske-Hall methods. The study suggests that the barrier is due mainly to the steric interactions. The exchange NMR study revealed two carbonyl exchange processes in both Ru3(CO)9(μ3-CO)(μ3-NPh) and Ru3(CO)8(PPh3)(μ3-CO)(μ3-NPh). The lower energy process is a tripodal rotation of the terminal carbonyls. The higher energy process, resulting in the exchange between the equatorial and bridging carbonyls, but not between the axial and bridging carbonyls, involves the concerted formation of edge-bridging μ2-CO moieties. The effect of the PPh3 ligand on the carbonyl exchange rates has been discussed. A combination of relaxation and exchange NMR found that PPh3 ligand rotation about the Ru-P bond is slow on the exchange NMR time scale and the phenyl rotation about the P-Cipso bond is fast on the exchange NMR time scale but is slow on the NMR relaxation time scale.

Introdução: O déficit de rotação interna glenoumeral, freqüentemente observado em praticantes de esportes que envolvem movimentos repetidos do membro superior sobre a cabeça, tem sido associado ao surgimento de lesões secundárias no ombro. Objetivos: Medir e comparar a amplitude de rotação interna glenoumeral em praticantes assintomáticos de tênis e natação, esportes com características diferentes, mas que envolvem esse tipo de movimento. Métodos: 54 voluntários assintomáticos do sexo masculino (108 ombros) divididos em 3 grupos (tenistas, nadadores, grupo-controle) foram submetidos à medida da amplitude de rotação interna glenoumeral através do método de exame clínico com estabilização da escápula (delineamento de pesquisa: estudo transversal). Foram comparadas as medidas dos ombros dominante e não dominante dentro de cada grupo e entre os grupos. Resultados: Em todos os grupos, o ombro dominante apresentou déficit de rotação interna se comparado com o não dominante. No grupo de tenistas o déficit médio foi de 23,9° ± 8,4° (P< 0,001), no de nadadores foi de 12° ± 6,8° (P< 0,001), e no grupocontrole de 4,9° ± 7,4° (P= 0,035). Comparados os membros dominantes entre os grupos, houve diferença entre todos, sendo o déficit apresentado pelos tenistas em relação ao grupo-controle (27,6°;P< 0,001) maior do que o dos nadadores (17,9°; P<0,001); entre tenistas e nadadores, foi de 9,7°;P=0,002). Conclusões: O membro dominante apresentou menor amplitude de rotação interna glenoumeral do que o não dominante em todos os grupos, sendo o déficit dos tenistas cerca de duas vezes maior do que o dos nadadores. A diferença média entre os membros no grupo controle foi menor do que 5°, o que está dentro do parâmetro de normalidade de acordo com a maioria dos estudos. Todos os grupos apresentaram diferenças se comparados os membros dominantes entre si. Os tenistas apresentaram a menor amplitude de rotação interna seguidos pelos nadadores. / Background: Glenohumeral internal rotation deficit, often diagnosed in players of overhead sports, has been associated with the development of secondary shoulder pathologies. Aim: To measure and compare the range of glenohumeral internal rotation motion in asymptomatic tennis players and in swimmers, different sports that share this overhead movements. Methods: Fifty-four asymptomatic male volunteers (108 shoulders) divided in 3 groups (tennis players, swimmers, control group) underwent measurements of glenohumeral internal rotation using clinical examination with scapular stabilization (study design: cross-sectional study). Measurements of dominant and nondominant shoulders were compared within and between groups. Results: In tennis players, mean déficit was 23.9° ± 8.4° (P< 0.001); in swimmers, 12° ± 6.8° (P< 0.001); and in the control group, 4.9° ± 7.4° (P= 0.035). Dominant shoulders showed significant difference between all groups, and the déficit of the group of tennis players in comparison with the control group (27.6°;P< 0.001) was greater than the deficit found in the group of swimmers (17.9°; P<0.001); between tennis players and swimmers, the deficit was 9.7°;P=0.002). Conclusions: Dominant limbs showed less glenohumeral internal rotation than the nondominant limbs in all groups, being the deficit in the group of tennis players about twice the deficit found for swimmers. Mean difference between limbs in the control group was less than 5°, which is within normal parameters according to most studies. There were statistically significant differences between all groups when dominant shoulders were compared to each other. Tennis players had the least range of motion, followed by swimmers.

Introdução: O déficit de rotação interna glenoumeral, freqüentemente observado em praticantes de esportes que envolvem movimentos repetidos do membro superior sobre a cabeça, tem sido associado ao surgimento de lesões secundárias no ombro. Objetivos: Medir e comparar a amplitude de rotação interna glenoumeral em praticantes assintomáticos de tênis e natação, esportes com características diferentes, mas que envolvem esse tipo de movimento. Métodos: 54 voluntários assintomáticos do sexo masculino (108 ombros) divididos em 3 grupos (tenistas, nadadores, grupo-controle) foram submetidos à medida da amplitude de rotação interna glenoumeral através do método de exame clínico com estabilização da escápula (delineamento de pesquisa: estudo transversal). Foram comparadas as medidas dos ombros dominante e não dominante dentro de cada grupo e entre os grupos. Resultados: Em todos os grupos, o ombro dominante apresentou déficit de rotação interna se comparado com o não dominante. No grupo de tenistas o déficit médio foi de 23,9° ± 8,4° (P< 0,001), no de nadadores foi de 12° ± 6,8° (P< 0,001), e no grupocontrole de 4,9° ± 7,4° (P= 0,035). Comparados os membros dominantes entre os grupos, houve diferença entre todos, sendo o déficit apresentado pelos tenistas em relação ao grupo-controle (27,6°;P< 0,001) maior do que o dos nadadores (17,9°; P<0,001); entre tenistas e nadadores, foi de 9,7°;P=0,002). Conclusões: O membro dominante apresentou menor amplitude de rotação interna glenoumeral do que o não dominante em todos os grupos, sendo o déficit dos tenistas cerca de duas vezes maior do que o dos nadadores. A diferença média entre os membros no grupo controle foi menor do que 5°, o que está dentro do parâmetro de normalidade de acordo com a maioria dos estudos. Todos os grupos apresentaram diferenças se comparados os membros dominantes entre si. Os tenistas apresentaram a menor amplitude de rotação interna seguidos pelos nadadores. / Background: Glenohumeral internal rotation deficit, often diagnosed in players of overhead sports, has been associated with the development of secondary shoulder pathologies. Aim: To measure and compare the range of glenohumeral internal rotation motion in asymptomatic tennis players and in swimmers, different sports that share this overhead movements. Methods: Fifty-four asymptomatic male volunteers (108 shoulders) divided in 3 groups (tennis players, swimmers, control group) underwent measurements of glenohumeral internal rotation using clinical examination with scapular stabilization (study design: cross-sectional study). Measurements of dominant and nondominant shoulders were compared within and between groups. Results: In tennis players, mean déficit was 23.9° ± 8.4° (P< 0.001); in swimmers, 12° ± 6.8° (P< 0.001); and in the control group, 4.9° ± 7.4° (P= 0.035). Dominant shoulders showed significant difference between all groups, and the déficit of the group of tennis players in comparison with the control group (27.6°;P< 0.001) was greater than the deficit found in the group of swimmers (17.9°; P<0.001); between tennis players and swimmers, the deficit was 9.7°;P=0.002). Conclusions: Dominant limbs showed less glenohumeral internal rotation than the nondominant limbs in all groups, being the deficit in the group of tennis players about twice the deficit found for swimmers. Mean difference between limbs in the control group was less than 5°, which is within normal parameters according to most studies. There were statistically significant differences between all groups when dominant shoulders were compared to each other. Tennis players had the least range of motion, followed by swimmers.