The effect of implant design on insertion torque and immediate micromotion

Objectives: To evaluate the effect of insertion torque on micromotion to a lateral force in three different implant designs. Material and methods: Thirty-six implants with identical thread design, but different cutting groove design were divided in three groups: (1) non-fluted (no cutting groove, solid screw-form); (2) fluted (901 cut at the apex, tap design); and (3) Blossomt (Patent pending) (non-fluted with engineered trimmed thread design). The implants were screwed into polyurethane foam blocks and the insertion torque was recorded after each turn of 901 by a digital torque gauge. Controlled lateral loads of 10N followed by increments of 5 up to 100N were sequentially applied by a digital force gauge on a titanium abutment. Statistical comparison was performed with two-way mixed model ANOVA that evaluated implant design group, linear effects of turns and displacement loads, and their interaction. Results: While insertion torque increased as a function of number of turns for each design, the slope and final values increased (Po0.001) progressively from the Blossomt to the fluted to the non-fluted design (M +/- standard deviation [SD] = 64.1 +/- 26.8, 139.4 +/- 17.2, and 205.23 +/- 24.3 Ncm, respectively). While a linear relationship between horizontal displacement and lateral force was observed for each design, the slope and maximal displacement increased (Po0.001) progressively from the Blossomt to the fluted to the non-fluted design (M +/- SD 530 +/- 57.7, 585.9 +/- 82.4, and 782.33 +/- 269.4 mm, respectively). There was negligible to moderate levels of association between insertion torque and lateral displacement in the Blossomt, fluted and non-fluted design groups, respectively. Conclusion: Insertion torque was reduced in implant macrodesigns that incorporated cutting edges, and lesser insertion torque was generally associated with decreased micromovement. However, insertion torque and micromotion were unrelated within implant designs, particularly for those designs showing the least insertion torque.

Electromagnetic torque ripple and copper losses reduction in permanent magnet synchronous machines

This paper presents a method for electromagnetic torque ripple and copper losses reduction in (non-sinusoidal or trapezoidal) surface-mount permanent magnet synchronous machines (SM-PMSM). The method is based on an extension of classical dq transformation that makes it possible to write a vectorial model for this kind of machine (with a non-sinusoidal back-EMF waveform). This model is obtained by the application of that transformation in the classical machine per-phase model. That transformation can be applied to machines that have any type of back-EMF waveform, and not only trapezoidal or square-wave back-EMF waveforms. Implementation results are shown for an electrical converter, using the proposed vectorial model, feeding a non-sinusoidal synchronous machine (brushless DC motor). They show that the use of this vectorial mode is a way to achieve improvements in the performance of this kind of machine, considering the electromagnetic torque ripple and copper losses, if compared to a drive system that employs a classical six-step mode as a converter. Copyright (C) 2011 John Wiley & Sons, Ltd.

Complex mixed state of the Pauli-limited superconductor CeCoIn5

Magnetization measurements were performed on CeCoIn5 at temperatures down to 20 mK and magnetic fields up to 17 T applied along different crystallographic orientations. For field configurations nearly parallel to the ab plane (theta less than or similar to 40 degrees and T <= 50 mK), we have found an intriguing vortex dynamics regime revealed by a hysteretic and metastable anomalous peak effect (APE), which gives evidence of surface barrier effects enhanced by antiferromagnetic fluctuations in the mixed state of CeCoIn5. Furthermore, we have observed crossover features in the torque and magnetization traces at fields below H-c2, which are consistent with vortices lattice phase transitions and with the anomalies speculated to be the Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) superconducting state in CeCoIn5. All of the above features were found to be dramatically perturbed in Ce0.98Gd0.02CoIn5.

Preliminary study of Porcine circovirus type 2 and Torque teno sus virus coinfection frequencies in Brazilian pig herds

Torque teno sus virus (TTSuV) is emergent in swine herds. Recent studies have shown an increased frequency of TTSuV2 in Porcine circovirus type 2 (PCV2)-associated diseases (PCVAD), which are endemic in many swine-producing countries, including Brazil. Coinfection with several other viral and bacterial agents results in an increased incidence of more severe PCVAD. Given the limited information on TTSuV and PCV2 coinfection, especially in Brazilian swine herds, this study made a preliminary estimation of the occurrence of coinfection in swine herds by testing samples from different categories. Between 2008 and 2009, 111 samples of feces and 23 serum samples from 5 swine herds were tested for PCV2 and TTSuVs and the results analyzed for associations between these agents. No significant differences in coinfection frequency were observed for PCV2 1 + TTSuV1 or for PCV2 1 TTSuV2 between nursery piglets (P = 0.730), growing pigs (P = 0.331), or sows (P = 0.472). However, a significant difference was observed for PCV2 1 TTSuV1 1 TTSuV2 between nursery piglets and growing pigs (P = 0.004; Fisher's exact test). Phylogenetic studies agreed with the grouping of TTSuV1 and TTSuV2 into 2 different clades, with no distinct pattern of clustering of these isolates with the animal categories.

Evaluation of peak cough flow in Brazilian healthy adults

Abstract Introduction In this study we aimed to evaluate the peak cough flow (PCF) in healthy Brazilian subjects. Methods We evaluated 484 healthy subjects between 18 and 40 years old. Subjects were seated and oriented were asked to perform a maximal inspiration followed by a quick, short and explosive expiration on the peak flow meter. Three measures were carried out and recorded the average of the three results for each individual. Results The PCF values ranged between 240 and 500 L/min. The PCF values were lower in females than in males. The PCF was inversely proportional to age. Conclusion The values for Brazilian adult healthy subjects regarding PCF were between 240 and 500 L/min.

Avaliação do torque de resistência passiva em atletas femininas com entorse de tornozelo

INTRODUÇÃO: A entorse de tornozelo é uma das lesões mais comuns em atletas. Uma forma de avaliar a frouxidão ligamentar pode ser através da medida da amplitude passiva dos movimentos de inversão e eversão do pé para estimar a resistência passiva das estruturas capsuloligamentares do tornozelo, o qual pode ser chamado de torque de resistência passiva. Existem poucos estudos que utilizam a avaliação do torque passivo do tornozelo para avaliar a resistência da cápsula e dos ligamentos. OBJETIVO: O objetivo deste estudo foi comparar o torque passivo dos movimentos de inversão e eversão do pé em atletas com e sem história de entorse de tornozelo. MÉTODO: Participaram do estudo 32 atletas de basquetebol e voleibol feminino (16,06 ± 0,8 anos, 67,63 ± 8,17kg, 177,8 ± 6,47cm). Seus tornozelos foram divididos em dois grupos: grupo controle (29), composto por tornozelos sem sintomas, e grupo entorse de tornozelo, composto por tornozelos que sofreram lesão (29). O torque dos movimentos passivos do tornozelo foi registrado por um dinamômetro isocinético, e a atividade dos músculos fibular longo e tibial anterior foi medida por um eletromiógrafo. As atletas realizaram duas repetições do movimento de inversão e eversão, nas velocidades de 5, 10 e 20°/s e, em seguida, o mesmo protocolo foi repetido apenas para o movimento de inversão máxima do pé. RESULTADOS: O torque de resistência passiva durante os movimentos de inversão e eversão do pé foi menor no grupo com entorse do tornozelo. Este grupo também mostrou menor torque durante o movimento de inversão máxima do pé. Não foram observadas diferenças entre o movimento de inversão e eversão. CONCLUSÕES: A entorse de tornozelo leva a um menor torque de resistência passiva, indicando redução da resistência dos ligamentos colaterais do tornozelo e uma frouxidão articular mecânica.

Association between muscle strength and the cardiopulmonary status of individuals living with HIV/AIDS

OBJECTIVE: The purpose of this study was to compare aerobic function [anaerobic threshold (%_VVO2-AT), respiratory compensation point (%_VVO2-RCP) and peak oxygen uptake (_VVO2peak)] between physically active patients with HIV/AIDS and matched controls and to examine associations between disease status, poor muscle strength, depression (as estimated by the profile of mood states questionnaire) and the aerobic performance of patients. METHODS: Progressive treadmill test data for %_VVO2-AT (V-slope method), RCP and (_VVO2peak) were compared between 39 male patients with HIV/AIDS (age 40.6¡1.4 years) and 28 male controls (age 44.4¡2.1 years) drawn from the same community and matched for habitual physical activity. Within-patient data were also examined in relation to CD4+ counts (nadir and current data) and peak isokinetic knee torque. RESULTS: AT, RCP and (_VVO2peak) values were generally similar for patients and controls.Within the patient sample, binary classification suggested that AT, RCP and (_VVO2peak) values were not associated with either the nadir or current CD4+ count, but treadmill test variables were positively associated with peak isokinetic knee torque. CONCLUSION: The aerobic performance of physically active patients with HIV/AIDS is generally well conserved. Nevertheless, poor muscle strength is observed in some HIV/AIDS patients, which is associated with lower anaerobic power and (_VVO2peak), suggesting the possibility of enhancing the aerobic performance of patients with weak muscles through appropriate muscle-strengthening activities.