This report describes a simple and very sensitive modal interferometer (modalmetric) opto-acousti... more This report describes a simple and very sensitive modal interferometer (modalmetric) opto-acoustic detector primarily thought for digital acoustic communications. The mod-almetric device was made from a single-mode fiber spliced with a sensitive multimode fiber (s-MMF) strand. A nonlinear increase of the phase-shift and a higher effective sensitivity of the device were observed when the interaction length of the s-MMF in contact with the surface receiving acoustic signals was increased from 5 to 25 cm and also when the s-MMF was bent-scaling and bend effects. A sensitivity increase of 14.2 dB was measured for very weak acoustic signals caused by at least three interfering modes. All tests in the proof-of-principle basis were performed at 42.9 kHz carrier frequency and 1550 nm wavelength. K E Y W O R D S acoustic communications, acoustic monitoring, modal interferometer, modalmetric, opto-acoustic receiver, ultrasound
... 2. E. Udd, D. Nelson, C. Lawrence, JR Spingarn, B. Ferguson, in: Proceedings of The Three Axi... more ... 2. E. Udd, D. Nelson, C. Lawrence, JR Spingarn, B. Ferguson, in: Proceedings of The Three Axis Strain and Temperature Sensor of the OFS-11, Paper We3-18, 1996. 3. P. Raiti, Fiber optic sensors for smart skins applications. SPIE 1370 (1990), pp. 619. Full Text via CrossRef. ...
Page 1. 38 IEEE SENSORS JOURNAL, VOL. 5, NO. 1, FEBRUARY 2005 Wavelength Demodulation of Ultrabri... more Page 1. 38 IEEE SENSORS JOURNAL, VOL. 5, NO. 1, FEBRUARY 2005 Wavelength Demodulation of Ultrabright Green Light-Emitting Diodes for Electrical Current Sensing Ricardo M. Ribeiro, Luciana Martins, and Marcelo M. Werneck ...
... pp. 749-752 GU, c., HONG. J , MCMICHAEL, I , SAXENA, R , and MOK. F H.: 'Cross talk limi... more ... pp. 749-752 GU, c., HONG. J , MCMICHAEL, I , SAXENA, R , and MOK. F H.: 'Cross talk limited storage capacity of volume holographic memory'. ... HEANUE, JF, BASHAW, Mc, and HEssELiNK, L : 'Channel codes for digital holographic data storage', J. Opt. Soc. Ain., 1995, 12, pp. ...
This study compared splinted and non-splinted implant-supported prosthesis with and without a dis... more This study compared splinted and non-splinted implant-supported prosthesis with and without a distal proximal contact using a digital image correlation method. An epoxy resin model was made with acrylic resin replicas of a mandibular first premolar and second molar and with threaded implants replacing the second premolar and first molar. Splinted and non-splinted metal-ceramic screw-retained crowns were fabricated and loaded with and without the presence of the second molar. A single-camera measuring system was used to record the in-plane deformation on the model surface at a frequency of 1.0Hz under a load from 0 to 250N. The images were then analyzed with specialist software to determine the direct (horizontal) and shear strains along the model. Not splinting the crowns resulted in higher stress transfer to the supporting implants when the second molar replica was absent. The presence of a second molar and an effective interproximal contact contributed to lower stress transfer to the supporting structures even for non-splinted restorations. Shear strains were higher in the region between the molars when the second molar was absent, regardless of splinting. The opposite was found for the region between the implants, which had higher shear strain values when the second molar was present. When an effective distal contact is absent, non-splinted implant-supported restorations introduce higher direct strains to the supporting structures under loading. Shear strains appear to be dependent also on the region within the model, with different regions showing different trends in strain changes in the absence of an effective distal contact.
One of the most important properties of artificial teeth is the abrasion wear resistance, which i... more One of the most important properties of artificial teeth is the abrasion wear resistance, which is determinant in the maintenance of the rehabilitation's occlusal pattern. This in vitro study aims to evaluate the abrasion wear resistance of 7 brands of artificial teeth opposed to two types of antagonists. Seven groups were prepared with 12 specimens each (BIOLUX & BL, TRILUX & TR, BLUE DENT & BD, BIOCLER & BC, POSTARIS…
Intensive fish farming results in stress adversely effecting the performance of farmed fish. Plas... more Intensive fish farming results in stress adversely effecting the performance of farmed fish. Plasma cortisol is a validated measure of stress in fish. We evaluated the effect of a homeopathic complex on the cortisol level of Nile tilapias (Oreochromis niloticus). 60 animals with approximate average weight of 100 g each at the start of experiment were randomly distributed in six glass fiber water tanks, capacity 1000 liters, with a daily water renewal rate of 20%. They received one of two treatments: 30 animals in control treatment and 30 animals receiving the homeopathic complex Homeopatila 100. On days 1, 30 and 60, all fish were anesthetized and blood was collected by puncture on the caudal vein, to determine the levels of circulating cortisol. At the end of the experiment the fish receiving a homeopathic complex, had significantly lower circulating cortisol level (17.96 ng/mL ± 0.95) than the control group (38.68 ng/mL ± 1.21) (p < 0.05). Cortisol levels were significantly lower in the treated group than control, and the fish were larger in the treated group.
This report describes a simple and very sensitive modal interferometer (modalmetric) opto-acousti... more This report describes a simple and very sensitive modal interferometer (modalmetric) opto-acoustic detector primarily thought for digital acoustic communications. The mod-almetric device was made from a single-mode fiber spliced with a sensitive multimode fiber (s-MMF) strand. A nonlinear increase of the phase-shift and a higher effective sensitivity of the device were observed when the interaction length of the s-MMF in contact with the surface receiving acoustic signals was increased from 5 to 25 cm and also when the s-MMF was bent-scaling and bend effects. A sensitivity increase of 14.2 dB was measured for very weak acoustic signals caused by at least three interfering modes. All tests in the proof-of-principle basis were performed at 42.9 kHz carrier frequency and 1550 nm wavelength. K E Y W O R D S acoustic communications, acoustic monitoring, modal interferometer, modalmetric, opto-acoustic receiver, ultrasound
... 2. E. Udd, D. Nelson, C. Lawrence, JR Spingarn, B. Ferguson, in: Proceedings of The Three Axi... more ... 2. E. Udd, D. Nelson, C. Lawrence, JR Spingarn, B. Ferguson, in: Proceedings of The Three Axis Strain and Temperature Sensor of the OFS-11, Paper We3-18, 1996. 3. P. Raiti, Fiber optic sensors for smart skins applications. SPIE 1370 (1990), pp. 619. Full Text via CrossRef. ...
Page 1. 38 IEEE SENSORS JOURNAL, VOL. 5, NO. 1, FEBRUARY 2005 Wavelength Demodulation of Ultrabri... more Page 1. 38 IEEE SENSORS JOURNAL, VOL. 5, NO. 1, FEBRUARY 2005 Wavelength Demodulation of Ultrabright Green Light-Emitting Diodes for Electrical Current Sensing Ricardo M. Ribeiro, Luciana Martins, and Marcelo M. Werneck ...
... pp. 749-752 GU, c., HONG. J , MCMICHAEL, I , SAXENA, R , and MOK. F H.: 'Cross talk limi... more ... pp. 749-752 GU, c., HONG. J , MCMICHAEL, I , SAXENA, R , and MOK. F H.: 'Cross talk limited storage capacity of volume holographic memory'. ... HEANUE, JF, BASHAW, Mc, and HEssELiNK, L : 'Channel codes for digital holographic data storage', J. Opt. Soc. Ain., 1995, 12, pp. ...
This study compared splinted and non-splinted implant-supported prosthesis with and without a dis... more This study compared splinted and non-splinted implant-supported prosthesis with and without a distal proximal contact using a digital image correlation method. An epoxy resin model was made with acrylic resin replicas of a mandibular first premolar and second molar and with threaded implants replacing the second premolar and first molar. Splinted and non-splinted metal-ceramic screw-retained crowns were fabricated and loaded with and without the presence of the second molar. A single-camera measuring system was used to record the in-plane deformation on the model surface at a frequency of 1.0Hz under a load from 0 to 250N. The images were then analyzed with specialist software to determine the direct (horizontal) and shear strains along the model. Not splinting the crowns resulted in higher stress transfer to the supporting implants when the second molar replica was absent. The presence of a second molar and an effective interproximal contact contributed to lower stress transfer to the supporting structures even for non-splinted restorations. Shear strains were higher in the region between the molars when the second molar was absent, regardless of splinting. The opposite was found for the region between the implants, which had higher shear strain values when the second molar was present. When an effective distal contact is absent, non-splinted implant-supported restorations introduce higher direct strains to the supporting structures under loading. Shear strains appear to be dependent also on the region within the model, with different regions showing different trends in strain changes in the absence of an effective distal contact.
One of the most important properties of artificial teeth is the abrasion wear resistance, which i... more One of the most important properties of artificial teeth is the abrasion wear resistance, which is determinant in the maintenance of the rehabilitation's occlusal pattern. This in vitro study aims to evaluate the abrasion wear resistance of 7 brands of artificial teeth opposed to two types of antagonists. Seven groups were prepared with 12 specimens each (BIOLUX & BL, TRILUX & TR, BLUE DENT & BD, BIOCLER & BC, POSTARIS…
Intensive fish farming results in stress adversely effecting the performance of farmed fish. Plas... more Intensive fish farming results in stress adversely effecting the performance of farmed fish. Plasma cortisol is a validated measure of stress in fish. We evaluated the effect of a homeopathic complex on the cortisol level of Nile tilapias (Oreochromis niloticus). 60 animals with approximate average weight of 100 g each at the start of experiment were randomly distributed in six glass fiber water tanks, capacity 1000 liters, with a daily water renewal rate of 20%. They received one of two treatments: 30 animals in control treatment and 30 animals receiving the homeopathic complex Homeopatila 100. On days 1, 30 and 60, all fish were anesthetized and blood was collected by puncture on the caudal vein, to determine the levels of circulating cortisol. At the end of the experiment the fish receiving a homeopathic complex, had significantly lower circulating cortisol level (17.96 ng/mL ± 0.95) than the control group (38.68 ng/mL ± 1.21) (p < 0.05). Cortisol levels were significantly lower in the treated group than control, and the fish were larger in the treated group.
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