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1
Schiffman, Philip L. "A “Saw-Tooth” Pattern in Parkinson's Disease." Chest 87, no. 1 (1985): 124–26. http://dx.doi.org/10.1378/chest.87.1.124.
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Vincken, W., and M. G. Costo. "“Saw-tooth” Pattern in the Flow-volume Loop." Chest 88, no. 3 (1985): 480. http://dx.doi.org/10.1378/chest.88.3.480-a.
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Schiffman, Philip L. "“Saw-tooth” Pattern in the Flow-volume Loop." Chest 88, no. 3 (1985): 480–81. http://dx.doi.org/10.1378/chest.88.3.480-b.
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Babu, Akhila. "Patient-ventilator interaction: Unusual ventilator graphics and management using Positive End Expiratory Pressure – A case report." Indian Journal of Respiratory Care 03, no. 02 (2022): 509–11. http://dx.doi.org/10.5005/ijrc-3-1-509.
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Approximately 25% of patients receiving mechanical ventilation have significant patient ventilator asynchrony which is associated with prolonged duration of mechanical ventilation. Here we report an unusual presentation of ventilator graphics “saw tooth” appearance in both pressure-time and flow-time graphs. An increase in the applied PEEP level resolved the saw tooth pattern in the graphics. The possible explanation for the graphics displayed is heart-lung interaction which is cardiogenic oscillation. If this is true, then this pattern can be used as a clinical tool to apply lung inflation manoeuvres.
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Rendleman, Neal, and Stephen F. Quinn. "The answer is blowing in the wind: a pedunculated tumour with saw tooth flow-volume loop." Journal of Laryngology & Otology 112, no. 10 (1998): 973–75. http://dx.doi.org/10.1017/s0022215100142239.
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AbstractObstructing tumours of the upper airways have been demonstrated to alter the flow volume loop of pulmonary function testing. These alterations could be clues to the nature and location of the obstruction. This report describes a case of a pedunculated squamous cell carcinoma arising in the pharynx whose flow volume loop showed a saw tooth pattern which reflected the location and structure of the tumour.
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Elangovan, B., Tucha Kedir, Rabira GeletaIbsa, and Yonas Biruku Addis. "A Novel Steganographic Approach for Embedding Secret Text in Multiple Images with Saw Tooth Pattern." International Journal of Advanced Engineering Research and Science 6, no. 6 (2019): 508–11. http://dx.doi.org/10.22161/ijaers.6.6.53.
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Zhang, Hanjie, and Peter Kotanko. "Artificial Intelligence-Driven System to Automatically Identify Arterial Oxygen Saturation Saw-Tooth Pattern in Hemodialysis." Journal of the American Society of Nephrology 32, no. 10S (2021): 309. http://dx.doi.org/10.1681/asn.20213210s1309b.
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Nagai, A., H. Matsumiya, M. Hayashi, T. Kanemura, S. Yasui, and K. Konno. "Lesions of the arytenoid region in a patient with exertional dyspnoea." European Respiratory Journal 6, no. 7 (1993): 1065–66. http://dx.doi.org/10.1183/09031936.93.06071065.
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A 63 year old woman presented with a 3 year history of exertional dyspnoea. Spirometry suggested extrathoracic airway obstruction (decreased inspiratory flow and saw-tooth pattern of flow-volume curves), and bronchoscopy revealed structural lesions and a trembling motion in the arytenoid region, causing upper airway obstruction on forced respiratory efforts. As there were no abnormal findings other than the lesions, the exertional dyspnoea was probably caused by impaired movement of the arytenoid region.
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Neukirch, Françoise, Emmanuel Weitzenblum, Renata Liard, et al. "Frequency and Correlates of the Saw-Tooth Pattern of Flow-Volume Curves in an Epidemiological Survey." Chest 101, no. 2 (1992): 425–31. http://dx.doi.org/10.1378/chest.101.2.425.
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Lee, Jae-Yeap, Hu-Jong Lee, Myung-Hwa Jung, Sung-Ik Lee, Eun-Mi Choi, and W. N. Kang. "Saw-tooth pattern from flux jumps observed by high resolution M-H curves in MgB2 thin films." Journal of Applied Physics 108, no. 3 (2010): 033909. http://dx.doi.org/10.1063/1.3457674.
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Pisciotta, Alessandra, Michele De Maria, Tommaso Verdina, Elisa Fornasari, Anto de Pol, and Gian Maria Cavallini. "Anterior Capsule of the Lens: Comparison of Morphological Properties and Apoptosis Induction following FLACS and Standard Phacoemulsification Surgery." BioMed Research International 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/7242837.
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Purpose. Comparative evaluation of morphological features of anterior capsules and apoptosis induction in epithelial cells after femtosecond laser-assisted cataract surgery (FLACS) and standard phacoemulsification surgery. Methods. Group 1: 30 FLACS anterior capsulotomies and Group 2: 30 manual anterior continuous curvilinear capsulorhexes. All patients were operated on by the same experienced surgeon. Morphological features of the anterior capsules and apoptosis induction in epithelial cells were evaluated. Results. All patients revealed a significant mean best-corrected visual acuity (BCVA) improvement 3 months after surgery, and no major intraoperative nor postoperative complications occurred. The capsular epithelium appeared to be preserved in both groups. Scanning electron microscopy analysis revealed irregular saw-tooth shaped edges in capsules from Group 1 whereas capsules from Group 2 showed regular and smooth edges. A statistically significant higher expression of the downstream apoptotic effector cleaved caspase 3 was observed in Group 1. Conclusions. The saw-tooth appearance was likely due to the progressive sequence of laser pulses on the capsule. The low energy/high frequency properties of the laser pulse, combined with an overlapped pulse pattern, resulted in highly continuous morphology of capsule edges. The higher apoptosis induction in FLACS group might be due to photodisruption-dependent plasma generation and formation of cavitation bubbles.
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Meynadier, Laure, Jean-Pierre Valet, Franck C. Bassinot, Nicholas J. Shackleton, and Yohan Guyodo. "Asymmetrical saw-tooth pattern of the geomagnetic field intensity from equatorial sediments in the Pacific and Indian Oceans." Earth and Planetary Science Letters 126, no. 1-3 (1994): 109–27. http://dx.doi.org/10.1016/0012-821x(94)90245-3.
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Thornton, Ian M., and Todd S. Horowitz. "Searching Through Alternating Sequences: Working Memory and Inhibitory Tagging Mechanisms Revealed Using the MILO Task." i-Perception 11, no. 5 (2020): 204166952095801. http://dx.doi.org/10.1177/2041669520958018.
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We used the Multi-Item Localisation (MILO) task to examine search through two sequences. In Sequential blocks of trials, six letters and six digits were touched in order. In Mixed blocks, participants alternated between letters and digits. These conditions mimic the A and B variants of the Trail Making Test (TMT). In both block types, targets either vanished or remained visible after being touched. There were two key findings. First, in Mixed blocks, reaction times exhibited a saw-tooth pattern, suggesting search for successive pairs of targets. Second, reaction time patterns for vanish and remain conditions were identical in Sequential blocks—indicating that participants could ignore past targets—but diverged in Mixed blocks. This suggests a breakdown of inhibitory tagging. These findings may help explain the elevated completion times observed in TMT-B, relative to TMT-A.
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Hachinski, Vladimir C., Mortimer Mamelak, and John W. Norris. "Clinical Recovery and Sleep Architecture Degradation." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 17, no. 3 (1990): 332–35. http://dx.doi.org/10.1017/s0317167100030699.
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ABSTRACT:We achieved a unique and timely recording of cerebral activity in a 70 year old woman immediately pre- and post-stroke, while studying the effect of acute cerebral infarction on sleep-electroencephalogram (EEG) patterns. Normal patterns, except for increased wakefulness, were recorded during two pre-infarct polysomnograms. Immediately following cerebral infarction increased delta activity was recorded from the infarcted hemisphere only. Initially, REM sleep could not be recorded from either side; however, on the third post infarct day REM sleep returned. Background EEG levels from both hemispheres became progressively slower, flatter and simpler. In addition, sleep spindles and the distinctive saw-tooth wave forms of sleep almost disappeared. At one year post-stroke sleep-EEG rhythm recordings from both hemispheres became more similar except for persisting delta activity from the left hemisphere. Unexpected deterioration of sleep-EEG pattern recordings from the undamaged hemisphere taken during the patient's clinical recovery remains unexplained. Serial sleep recording may facilitate the study of brain recovery, activity and reorganization following stroke.
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KALLIADASIS, SERAFIM. "Nonlinear instability of a contact line driven by gravity." Journal of Fluid Mechanics 413 (June 25, 2000): 355–78. http://dx.doi.org/10.1017/s0022112000008508.
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A thin liquid mass of fixed volume spreading under the action of gravity on an inclined plane develops a fingering instability at the front. In this study we consider the motion of a viscous sheet down a pre-wetted plane with a large inclination angle. We demonstrate that the instability is a phase instability associated with the translational invariance of the system in the direction of flow and we analyse the weakly nonlinear regime of the instability by utilizing methods from dynamical systems theory. It is shown that the evolution of the fingers is governed by a Kuramoto–Sivashinsky-type partial differential equation with solution a saw-tooth pattern when the inclined plane is pre-wetted with a thin film, while the presence of a thick film suppresses fingering.
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Bauer, Peter, and Helmut Woschitz. "Laboratory Investigations of the Leica RTC360 Laser Scanner—Distance Measuring Performance." Sensors 24, no. 12 (2024): 3742. http://dx.doi.org/10.3390/s24123742.
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A Leica RTC360 laser scanner was investigated using a linear horizontal comparator system with four targets of different reflectance. Several thousand panorama scans were conducted along the 30 m long comparator, basically in 40 mm steps. For a selected target, more detailed investigations were carried out with a 2 mm step width for a 2 m wide section. The absolute offset between the scanner and the relative interferometer measurements was determined with a calibrated total station. The investigations revealed several systematic effects like an offset in the distance measurement of about 1.3 mm. Furthermore, sections with stochastic behavior as well as sections with pseudo-cyclic parts were observed, depending on the reflectance of the target. The deterministic sections showed curved and striped patterns with some discontinuities of about 2 mm at 20 m, resulting in a saw-tooth like pattern along the distances. Within all the experiments, the distance deviations were below the manufacturer specifications of the 3D point accuracy. However, it was demonstrated that the distance measurements had clear systematic components. In using these new findings, the specification of the measurement “noise” in the data sheet has to be seen as critical.
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Pothineni, Bhanu K., Sabrina Kollmann, Xinyang Li, Guido Grundmeier, Denise J. Erb, and Adrian Keller. "Adsorption of Ferritin at Nanofaceted Al2O3 Surfaces." International Journal of Molecular Sciences 24, no. 16 (2023): 12808. http://dx.doi.org/10.3390/ijms241612808.
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The influence of nanoscale surface topography on protein adsorption is highly important for numerous applications in medicine and technology. Herein, ferritin adsorption at flat and nanofaceted, single-crystalline Al2O3 surfaces is investigated using atomic force microscopy and X-ray photoelectron spectroscopy. The nanofaceted surfaces are generated by the thermal annealing of Al2O3 wafers at temperatures above 1000 °C, which leads to the formation of faceted saw-tooth-like surface topographies with periodicities of about 160 nm and amplitudes of about 15 nm. Ferritin adsorption at these nanofaceted surfaces is notably suppressed compared to the flat surface at a concentration of 10 mg/mL, which is attributed to lower adsorption affinities of the newly formed facets. Consequently, adsorption is restricted mostly to the pattern grooves, where the proteins can maximize their contact area with the surface. However, this effect depends on the protein concentration, with an inverse trend being observed at 30 mg/mL. Furthermore, different ferritin adsorption behavior is observed at topographically similar nanofacet patterns fabricated at different annealing temperatures and attributed to different step and kink densities. These results demonstrate that while protein adsorption at solid surfaces can be notably affected by nanofacet patterns, fine-tuning protein adsorption in this way requires the precise control of facet properties.
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Raisa A Sukhodolskaya, Anatoly A Saveliev, Nadezhda L Ukhova, et al. "Modeling sexual differences of body size variation in ground beetles in geographical gradient (The case study in Pterostichus oblongpunctatus Fabricius, 1787)." GSC Biological and Pharmaceutical Sciences 13, no. 3 (2020): 149–61. http://dx.doi.org/10.30574/gscbps.2020.13.3.0388.
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Fleshing out the mechanisms of Bergmann rule, we found saw-tooth pattern in body size variation in ground beetle Pterostichus oblongopunctatus. We sampled beetles in 2010 – 2018 at the forest undisturbed plots on the broad territory in Russia and Belarus. Investigating regions covered territory, extending to 3 degrees latitude and 31 degrees longitude. We measured six traits in every of 3294 caught individuals. ANOVA showed that geographical location and sex affected significantly body size of the species studied. Mean values of each trait changed significantly from one studied region to another in females and males as well. Sexual size dimorphism in species was female-biased. We performed models in R to estimate the steepness of body size variation in both sexes. In overwhelming majority of cases that parameter was equal in both sexes. So the hypothesis, that male′s variation is steeper in latitude gradient was not confirmed.
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Kim, Hyung Sik, Sang Pyo Hong, Mi Hyun Choi, et al. "A Study on the Characteristics of a Vibrator Using Flat PCB-Coil." Applied Mechanics and Materials 392 (September 2013): 738–42. http://dx.doi.org/10.4028/www.scientific.net/amm.392.738.
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In this study, we developed and evaluateda vibrator using a flat PCB-coil. The flat PCB-coil vibrator was fabricated on a printed circuit board using and etching process. The spiral pattern was etched on a fiberglass cloth with an epoxy resin. To evaluatethe flat PCB-coil vibrator, we generated a sine wave, saw-tooth, and square wave through a custom made wave generator and amplified the waveforms using a power amplifier. A three-axis accelerometer was used to evaluate the performance of the developed vibrator. Even though the developed vibrator is simple, it has a wide range of vibration frequency (50~500 Hz) and vibration amplitude (0~5 V). The vibration amplitude does not change due to frequency change. It is expected that the developed vibrator can be used in a wide variety of applications such as in a tactile stimulator, in elastography, energy harvesting, and in a cooling system.
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Longrich, Nicholas R., Xabier Pereda-Suberbiola, Nour-Eddine Jalil, and Nathalie Bardet. "A New Species of the Durophagous Mosasaurid Carinodens from the Late Maastrichtian Phosphates of Morocco and Implications for Maastrichtian Mosasaurid Diversity." Diversity 17, no. 1 (2024): 25. https://doi.org/10.3390/d17010025.
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Late Cretaceous marine ecosystems saw a major adaptive radiation of mosasaurids, which evolved highly disparate jaw and tooth morphologies to feed on different prey. A striking pattern seen in mosasaurids was a high diversity of durophagous forms. Durophagy likely evolved several times independently in the mosasaurine genera Globidens, Prognathodon, and Carinodens. Carinodens is unusual in having low, rectangular, laterally compressed teeth. The genus is known from around the world, with the species Carinodens minalmamar and C. belgicus previously reported from the Maastrichtian Phosphates of Morocco. Here, we report a new species of Carinodens, C. acrodon, from the same Maastrichtian Phosphates. It is characterized by teeth with tall crowns, triangular apices, and broad bases. Many of the diagnostic features of this species appear to be plesiomorphies, suggesting the persistence of a primitive species of Carinodens into the latest Maastrichtian alongside the more derived C. minalmamar and C. belgicus. The new species contributes to an emerging pattern of mosasaurid hyperdiversity in the late Maastrichtian of Morocco. A revised faunal list, including stratigraphic range extensions of Khinjaria and Stelladens into the latest Maastrichtian of upper Couche III of the Phosphates of Morocco, suggests at least 16 species of mosasauroid coexisted here.
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Sato, Atsuko, Nami Senda, Emi Fukui, and Kouichi Ohta. "Retinal Angiomatous Proliferation in an Eye with Cuticular Drusen." Case Reports in Ophthalmology 6, no. 1 (2015): 127–31. http://dx.doi.org/10.1159/000381616.
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Purpose: To report the presence of retinal angiomatous proliferation (RAP) in an eye with cuticular drusen detected by fluorescein and indocyanine green angiography by confocal scanning laser ophthalmoscopy and by spectral-domain optical coherence tomography (SD-OCT). Methods: Case report of a 65-year-old Japanese woman with cuticular drusen. Results: At her first ophthalmic examination, her visual acuity was 20/20 in both eyes. An ophthalmoscopy showed many small subretinal pigment epithelial deposits in both eyes. These deposits had a ‘saw-tooth pattern' in the SD-OCT images. During the follow-up examination, retinal hemorrhages were observed, and fluorescein angiography showed a ‘stars-in-the-sky' appearance and intraretinal neovascularization. The patient was diagnosed with cuticular drusen associated with RAP. Conclusion: We suggest that the cuticular drusen were associated with RAP, so periodic follow-up examinations are needed for patients with cuticular drusen for the early detection and treatment of RAP.
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Raisa, A. Sukhodolskaya, A. Saveliev Anatoly, L. Ukhova Nadezhda, et al. "Modeling sexual differences of body size variation in ground beetles in geographical gradient (The case study in Pterostichus oblongpunctatus Fabricius, 1787)." GSC Biological and Pharmaceutical Sciences 13, no. 3 (2020): 149–61. https://doi.org/10.5281/zenodo.4415171.
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Fleshing out the mechanisms of Bergmann rule, we found saw-tooth pattern in body size variation in ground beetle <em>Pterostichus oblongopunctatus</em>. We sampled beetles in 2010 – 2018 at the forest undisturbed plots on the broad territory in Russia and Belarus. Investigating regions covered territory, extending to 3 degrees latitude and 31 degrees longitude. We measured six traits in every of 3294 caught individuals. ANOVA showed that geographical location and sex affected significantly body size of the species studied. Mean values of each trait changed significantly from one studied region to another in females and males as well. Sexual size dimorphism in species was female-biased. We performed models in R to estimate the steepness of body size variation in both sexes. In overwhelming majority of cases that parameter was equal in both sexes. So the hypothesis, that male′s variation is steeper in latitude gradient was not confirmed.
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Abdur Rahman, K. M., Priyaranjan Sethy, Saswat Khatai, et al. "Chip morphology assessment in turning of hardened AISI 52100 steel under ZnO nanofluid environment." Journal of Physics: Conference Series 2818, no. 1 (2024): 012045. http://dx.doi.org/10.1088/1742-6596/2818/1/012045.
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Abstract The chip morphology in hard turning significantly impacts tool performance influenced by factors like strain softening, machining parameters, workpiece hardness, and tool geometry. In this current study, AISI 52100 steel of hardness (∼ 55 HRC) has been taken into consideration for the hard turning experiment and a detailed chip morphology study was conducted under ZnO nanofluid MQL (Minimum quantity lubrication) condition assisted by dual nozzle set up. The influence of machining parameters such as cutting speed, feed, depth of cut, and MQL flow rate on different chip morphology criteria like chip reduction coefficient, chip curl angle, chip pitch length, chip pattern, and colour has been studied thoroughly in this investigation. From the experimental study, it was observed that CRC is influenced by the depth of cut while chip curl angle and chip pitch length are majorly influenced by feed followed by cutting speed. Helical, wavy, and spiral shape chips followed by saw-tooth formation chips were observed in the entire investigation. However, spiral chips and blue colour chips were noticed at higher feed and higher cutting speed conditions respectively.
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Snowball, Ian, and Matthias Moros. "Saw-tooth pattern of North Atlantic current speed during Dansgaard-Oeschger cycles revealed by the magnetic grain size of Reykjanes Ridge sediments at 59°N." Paleoceanography 18, no. 2 (2003): n/a. http://dx.doi.org/10.1029/2001pa000732.
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Jerry Qi, H., Christine Ortiz, and Mary C. Boyce. "Mechanics of Biomacromolecular Networks Containing Folded Domains." Journal of Engineering Materials and Technology 128, no. 4 (2006): 509–18. http://dx.doi.org/10.1115/1.2345442.
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The force-extension behavior of single modular biomacromolecules is known to exhibit a characteristic repeating pattern of a nonlinear rise in force with imposed displacement to a peak, followed by a significant force drop upon reaching the peak. This “saw-tooth” pattern is a result of stretch-induced unfolding of modules along the molecular chain and is speculated to play a governing role in the function of biological materials and structures. In this paper, constitutive models for the large strain deformation of networks of modular macromolecules are developed building directly from statistical mechanics based models of the single molecule force-extension behavior. The proposed two-dimensional network model has applicability to biological membrane skeletons and the three-dimensional network model emulates cytoskeletal networks, natural fibers, and soft biological tissues. Simulations of the uniaxial and multiaxial stress-strain behavior of these networks illustrate the macroscopic membrane and solid stretching conditions which activate unfolding in these microstructures. The models simultaneously track the evolution in underlying microstructural features with different macroscopic stretching conditions, including the evolution in molecular orientation and the forces acting on the constituent molecular chains and junctions. The effect of network pretension on the stress-strain behavior and the macroscopic stress and strain conditions which trigger unfolding are presented. The implications of the predicted stress-strain behaviors on a variety of biological materials are discussed.
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Ding, Wenqi, Chao Duan, and Qingzhao Zhang. "Experimental and Numerical Study on a Grouting Diffusion Model of a Single Rough Fracture in Rock Mass." Applied Sciences 10, no. 20 (2020): 7041. http://dx.doi.org/10.3390/app10207041.
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Grouting reinforcement is an important method used to solve problems encountered during tunnel construction, such as collapse and water gushing. The grouting diffusion process is greatly influenced by the structural characteristics of the fractures in a rock mass. First, an analytical grouting diffusion model of a single rough fracture under constant-pressure control is established based on the constitutive equation of a Bingham fluid. Second, the “quasi-elliptical” grouting diffusion pattern under the influence of roughness is revealed through a grouting diffusion experiment, which is conducted with an independently developed visualized testing apparatus. Furthermore, the analytical formula of roughness-corrected grouting diffusion characterized by the saw tooth density is established. Finally, an elaborate numerical simulation of the diffusion process of cement slurry (Bingham flow type) in a single rough fracture is carried out by introducing the Bingham–Papanastasiou rheological model. The temporal and spatial distribution characteristics of the velocity field and pressure field during the grouting diffusion process are analyzed as well. Moreover, the method and range of the roughness correction factor in the analytical grouting diffusion model are proposed based on the fracture roughness unit.
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Pan, Zhiyong, Liang Wang, Jiamei Jin, Jianmin Qiu, Haoren Feng, and Ying Yang. "Design, simulation, and experimental investigation on a novel multi-drive pattern three-degree-of-freedom rotary piezoelectric motor." Smart Materials and Structures 32, no. 12 (2023): 125022. http://dx.doi.org/10.1088/1361-665x/ad0b1c.
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Abstract Three-degree-of-freedom (3-DOF) rotary piezoelectric motors often suffer from low positioning accuracy, complex excitation signals, and uneven preloading, limiting their application in precision drive systems. To address these issues, this study proposes a novel multi-drive pattern 3-DOF rotary piezoelectric motor, comprising a sandwich-type hollow cylindrical stator, a spherical rotor, and a pre-tightening structure. The proposed motor can operate in both inertial and traveling wave drive patterns. In the inertial drive pattern, the first-order and the third-order bending vibration modes of the stator are simultaneously excited by a sawtooth wave signal, generating a saw-tooth displacement on its driving feet to rotate the rotor around the x or y-axis. In the traveling wave drive pattern, two mutually orthogonal first-order bending vibration modes of the stator are simultaneously stimulated by two sinusoidal signals, generating a traveling wave on its driving feet to rotate the rotor around the z-axis. Initially, finite element analysis is used to simulate the operating principle of the stator and determine its geometric dimensions. Subsequently, a prototype of the sandwich-type hollow cylindrical stator is fabricated, and its vibration characteristics are tested to confirm the validation of the proposed operating principle and the correctness of the finite element simulation. Finally, a prototype of the proposed 3-DOF rotary piezoelectric motor is assembled, and its mechanical output characteristics are experimentally evaluated. Experimental results indicate that when the excitation voltage is 200 Vpp, the no-load rotary velocities of the motor prototype in three rotation directions are 79 r min−1, 76 r min−1, and 101 r min−1, respectively, start/stop response times are 10 ms/8.6 ms, 13.4 ms/6.2 ms, and 15.5 ms/7.7 ms, respectively, and the angular displacement resolutions are 7.4 μrad, 8 μrad, and 11.4 μrad, respectively. The proposed motor exhibits high mechanical integration, 3-DOF rotation, few excitation signals, adjustable pre-tightening force, and high positioning accuracy advantages, holding the potential applications in fields such as robotic technology and space pointing mechanisms.
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Girgenrath, M., and R. L. Marsh. "In vivo performance of trunk muscles in tree frogs during calling." Journal of Experimental Biology 200, no. 24 (1997): 3101–8. http://dx.doi.org/10.1242/jeb.200.24.3101.
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We used high-speed video and electromyography (EMG) to measure in vivo performance of the trunk muscles (external obliques) in two related species of North American gray tree frogs, Hyla versicolor and Hyla chrysoscelis. Both species produce trilled calls with high sound intensity, but the sound pulse frequency within calls in H. chrysoscelis is twice that in H. versicolor. In both species, sound pulse frequency is directly correlated with the active contractions of the trunk muscles. The length trajectory during contraction and relaxation displays a saw-tooth pattern with a longer shortening phase compared with the lengthening phase. The longer time spent shortening may enhance power production, because the shortening phase is the active part of the cycle during which the muscle produces positive work. A similar total strain (approximately 21 % and approximately 19 % in H. versicolor and H. chrysoscelis respectively) is achieved in the first few pulses, and during subsequent pulses the muscle cycles with a reduced pulse strain (approximately 12 % and approximately 7.3 % in H. versicolor and H. chrysoscelis respectively). The higher pulse frequencies of H. chrysoscelis are thus associated with lower pulse strains. The EMG pattern is different in the two species. A single EMG stimulus occurs for each cycle in H. chrysoscelis, but two stimuli per cycle are found in H. versicolor. Indirect evidence suggests that the initial phase of shortening during a pulse is partly due to elastic recoil of the trunk.
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Suman, Anshika, Shyamalendu Laskar, Parth Sharma, Anshu Nishchhal, Shambo Dey, and Prasanta Majumder. "Measurement and Comparison of Pattern of Bone Destruction in Chronic Periodontitis Patients with and Without Smoking Habit: A Cross-Sectional Study." Journal of Pharmacy and Bioallied Sciences 17, Suppl 2 (2025): S1408—S1411. https://doi.org/10.4103/jpbs.jpbs_1737_24.
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ABSTRACT Background: Smoking is a major risk factor for the development and advancement of periodontal disorders, which in turn cause the loss of periodontal attachment, deeper pockets, and the loss of tooth and alveolar bone. Aim: The purpose of this research is to use radiovisiography (RVG) radiographs in conjunction with transgingival probing to assess and quantify the pattern and degree of alveolar bone deterioration in individuals with chronic periodontitis (CP), whether or not they smoke. Materials and Methods: The research comprised 50 male volunteers with CP, 25 of whom were smokers and 25 of whom were not. Patients in Group A were those who were systemically healthy, had clinical attachment loss of ≥3 mm, were between the ages of 25 and 50, smoked 100 cigarettes or more throughout their lifetime, and were not smokers at the time of the interview. Group B was made up of non-smokers. Clinical data were documented, including clinical attachment loss (CAL), plaque index (PI), and probing pocket depth (PPD). RVG and transgingival probing were used to measure the amount and pattern of bone loss. Results: Compared to non-smokers, cigarette smokers had higher and statistically significant mean values for PI, PPD, and CAL. In the maxillary arch, cigarette smokers saw more bone loss than non-smokers. In cigarette smokers, the types of bone damage exhibited a more vertical pattern. Conclusion: In conclusion, it was shown that those who smoke have more bone loss than those who do not smoke. Since digital radiography has the ability to quantify bone change more precisely, transgingival probing in conjunction with RVG is a better way to evaluate bone loss.
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Stewardson, Dominic A., Russell J. Crisp, Siobhan McHugh, Urs Lendenmann, and FJ Trevor Burke. "The Effectiveness of Systemp.desensitizer in the Treatment of Dentine Hypersensitivity." Primary Dental Care os11, no. 3 (2004): 71–76. http://dx.doi.org/10.1308/1355761041208511.
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Purpose This study reports the effectiveness of Systemp.desensitizer (Ivoclar Vivadent, Schaan, Liechtenstein), when used both with and without an acid-etch step, in the treatment of patients with dentine hypersensitivity in UK dental practices. Materials and methods Ten general dental practitioners (GDPs) were selected from two practice-based research groups. The GDPs were each requested to use Systemp.desensitizer in the treatment of at least ten patients who presented with pain due to dentine hypersensitivity. Systemp.desensitizer was applied to the sensitive dentine area in strict accordance with the manufacturer's handling instructions, except that the patients were divided into two groups. For the first, group NE, the procedure was to isolate the tooth, gently blot it dry with cotton wool pellets, rub Systemp.desensitizer into the tooth for 20 seconds, then gently air-dry it. For the second, group E, the procedure was identical except that after isolation, the treatment area was etched for 15 seconds with 35% phosphoric acid. Patients were asked to complete a pro forma using a 10 cm visual analogue scale designed to provide details of the extent of their pain before treatment, 24 hours post-treatment, one week post-treatment, one month post-treatment, and three months post-treatment. The zero end of the scale was marked ‘no pain’ and the 10 cm end was marked ‘extreme pain’. The percentage change in the patients’ perception of their pain, relative to pretreatment, was calculated using repeated measures analysis and suitable follow-up confidence intervals for the mean changes in perceived pain. Comparisons were then made between the treatment groups NE and E. Results Ninety-one patients completed the first pro forma and 77 completed all the pro formas. Overall, there was a significant reduction in pain at each of the time points after treatment but the pattern of pain reduction across the two groups was different. In general, the non-etched group (group NE) saw an ‘immediate’ reduction in pain which was then fairly consistent across the longer term, whilst, in general, the etched group (group E) saw less reduction in pain 24 hours after treatment, and then further reduction in pain at both one week and one month after treatment. Thus the non-etched group experienced an early reduction whilst the etched group took longer to perceive a reduction in pain; however, there were no statistically significant differences between the reductions in pain scores between the two groups at any of the time points after treatment. Conclusion It is concluded that Systemp.desensitizer was effective in reducing pain from dentine hypersensitivity in the patients treated, and this finding was unaffected by whether or not the tooth was acid-etched prior to application of the reagent.
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Kleinhans, M. G., T. M. van Rosmalen, C. Roosendaal, and M. van der Vegt. "Turning the tide: mutually evasive ebb- and flood-dominant channels and bars in an experimental estuary." Advances in Geosciences 39 (April 1, 2014): 21–26. http://dx.doi.org/10.5194/adgeo-39-21-2014.
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Abstract. Tidal bars in estuaries are poorly understood compared to fluvial bars. There is limited theory that predicts tidal bar dimensions. Moreover, where fluvial channels bifurcate around bars, tidal channels around bars often develop either flood- or ebb-dominance which remains unexplained. Tidal experiments are rare and have not reproduced these phenomena to date because these are usually highly ebb-dominated. Here we report preliminary experiments in a novel setup that produce tidal bars from an initial situation with flat bed and exactly symmetrical ebb- and flood-related sediment mobility. The bars initially develop in a saw-tooth pattern with mutually evasive ebb- and flood channels. The tips of the bars evolve further into lobate bars built up from sediment from excavating channels. The bar tips form steep and high obstructions for the opposing flow direction, which then diverges into evasive channels. The bars develop into a diamond shape as channels bifurcate and deepen around it. We further found that bar height correlates well to bar width but not with bar length, whilst bar length correlates well to the tidal excursion length. As the experiment progressed scour holes developed that affected the channel and bar pattern and are considered artifacts of the experiment. We conclude that the mutually evasive ebb- and flood-dominance of channels emerges simultaneously with the onset of tidal bar formation, and that these preliminary data confirm results from linear stability analyses. The results are proof of principle for the novel experimental setup for tidal systems.
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Gao, Dawei, Chenhui Hua, and Jiexiong Ding. "Research on excitation technology of high-throughput ultrasonic micro-separator based on micro-nano fabrication." Advances in Mechanical Engineering 14, no. 5 (2022): 168781322210962. http://dx.doi.org/10.1177/16878132221096229.
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The excitation technology of ultrasonic standing wave field is the core key to realize ultrasonic separation. This paper analyzes the excitation technology of (1, 1) mode ultrasonic separation of high-throughput ultrasonic micro-separator. There are two main problems: the coexistence of multiple modes in the separation cavity and the insufficient acoustic radiation force. In order to solve these two problems, this paper uses integrated circuit micromachining technology to process the ultrasonic micro-separator. The depth dimension of the cavity reaches 200 ± 0.5 µm, and the verticality of the side wall of the cavity reaches 83.36°. The degree of SFPD (Site Focal Plane Deviation) is less than or equal to 0.25 µm. Besides, this paper proposes an excitation method of saw-tooth frequency sweep of two anti-phase acoustic drivers. Finally, the experiments of the separator processed by the processing method proposed in this paper shows that, the excitation method proposed in this paper can effectively excite the (1, 1) mode, and shortens the time for the pattern formation of particle convergence, which greatly improves the separation efficiency. The separation throughput (flow rate) in one single cavity in this work can reach to 100 µl/min. It provides an effective basis for ultrasonic micro-separation technology.
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R. Nagaraju and Rajesh Kaza. "Formulation and Evaluation of Bilayer Sustained Release Tablets of Salbutamol and Theophylline." International Journal of Pharmaceutical Sciences and Nanotechnology 2, no. 3 (2009): 638–46. http://dx.doi.org/10.37285/ijpsn.2009.2.3.7.
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Salbutamol and theophylline are available in conventional dosage forms, administered four times a day, leading to saw tooth kinetics and resulting in ineffective therapy. The combination of these two drugs in a single dosage form will enhance the patient compliance and prolong bronchodilation. Various polymers, such as hydroxy propyl methylcellulose K4M (HPMC- K4M), hydroxy propyl methylcellulose K100M (HPMC- K100M), xanthan gum, ethyl cellulose and hydroxy propyl methylcellulose phthalate (HPMC-P) were studied. HPMC-P and HPMC- K4M were found to be best in controlling the release. In-vitro dissolution studies were carried out for all the bi-layered tablets developed using USP dissolution apparatus type 2 (paddle). It was found that the tablet FB15-FW3 showed 50% release of salbutamol in first hour and the remaining was released for eight hours. However, theophylline was found to be released as per the USP specifications. The IR spectrum was taken for FB15-FW3 formulation and it revealed that there is no disturbance in the principal peaks of pure drugs salbutamol and theophylline. This further confirms the integrity of pure drugs and no incompatibility of them with excipients. Also, formulation of FB15-FW3 has shown required release pattern and complies with all the evaluated parameters and comparable to the marketed formulation.
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Orland, Ian J., Miryam Bar-Matthews, Noriko T. Kita, Avner Ayalon, Alan Matthews, and John W. Valley. "Climate deterioration in the Eastern Mediterranean as revealed by ion microprobe analysis of a speleothem that grew from 2.2 to 0.9 ka in Soreq Cave, Israel." Quaternary Research 71, no. 1 (2009): 27–35. http://dx.doi.org/10.1016/j.yqres.2008.08.005.
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AbstractAnalysis of oxygen isotope ratios (δ18O) by ion microprobe resolves a sub-annual climate record for the Eastern Mediterranean from a Soreq Cave stalagmite that grew between 2.2 and 0.9 ka. In contrast to conventional drill-sampling methods that yield a total variation of 1.0‰ in δ18Ocalcite values across our sample, the methods described here reveal up to 2.15‰ variation within single annual growth bands. Values of δ18O measured by ion microprobe vary in a regular saw-tooth pattern that correlates with annual, fluorescent growth banding where calcite grades from light to dark fluorescence. Modern records of precipitation and of cave dripwater indicate that variable δ18Ocalcite values record regular seasonal differences in δ18Orainfall modified by mixing in the vadose zone. Large differences in δ18O values measured across a single band (i.e., between the dark and light fluorescent calcite, or Δ18Odark-light) are interpreted to indicate wetter years, while smaller differences represent drier years. Oxygen isotopes record: 1) month-scale growth increments, 2) changes in Δ18Odark-light that represent seasonality, 3) a systematic, long-term decrease in maximum Δ18Odark-light values, and 4) an overall increase in average δ18Ocalcite values through time. These results suggest a drying of regional climate that coincides with the decline of the Roman and Byzantine Empires in the Levant region.
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Gaponenko, Y. A., M. Torregrosa, V. Yasnou, A. Mialdun, and V. Shevtsova. "Dynamics of the interface between miscible liquids subjected to horizontal vibration." Journal of Fluid Mechanics 784 (November 4, 2015): 342–72. http://dx.doi.org/10.1017/jfm.2015.586.
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We present experimental evidence of the existence of an interfacial instability between two miscible liquids of similar (but non-identical) viscosities and densities under horizontal vibration. A stably stratified two-layer system is composed of the same binary mixture with different concentrations placed in a confined cell (with length twice as large as the height). Unlike the case of immiscible fluids, here, the interface is a transient layer of small but non-zero thickness. In the experiments, the frequency and amplitude were varied within the ranges 2–24 Hz and 1.5–16 mm, respectively. When the value of the oscillatory forcing increases, the amplitudes of the interface perturbations grow continuously, forming a saw-tooth frozen structure. This evolution is also examined numerically. In addition to the solutions of full 3-D Navier–Stokes equations, an averaging approach with separation of time scales is used for situations in which the forcing period is very small compared to the natural time scales of the problem. The simulation of averaged equations provides the explanation of the instability development, the calculations of the full nonlinear equations shed light on the decay of a wavy pattern. The results of numerical modelling perfectly support the experimental observations.
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Zijdewind, Inge, and Daniel Kernell. "Bilateral Interactions During Contractions of Intrinsic Hand Muscles." Journal of Neurophysiology 85, no. 5 (2001): 1907–13. http://dx.doi.org/10.1152/jn.2001.85.5.1907.
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During demanding voluntary contractions (e.g., high force or fatigue), activation is not restricted to the target muscle but extends to other ipsilateral muscles; even contralateral muscles become activated. The contralateral “irradiation” of activity was measured in five subjects during submaximal and maximal voluntary contractions (MVCs) of the first dorsal interosseous (FDI) (index finger abduction) and during unfatigued and fatigued conditions. All subjects were tested five times with at least one week between tests. Unilateral MVCs were associated with a substantial amount of contralateral FDI activation [mean = 7.9 ± 6.7% (SD) MVC prior to fatigue]. The amount of such contralateral irradiation was significantly different between different individuals and was positively correlated between dominant and nondominant hands. During fatigue tests, the contractile activity of the contralateral “nontarget” index finger showed progressive increase (force, electromyogram) as was measured during both the submaximal task and interspersed MVCs of the target finger. In addition, a superimposed saw-tooth pattern of intermittently waxing and waning contractions commonly appeared contralaterally. The expression of contralateral irradiation force was itself fatigue-sensitive: less irradiation was seen in a recently fatigued muscle than was seen before the fatigue test. These fatigue effects could not be explained as having been caused by changes in muscle properties. Possible anatomical sites of contralateral irradiation are briefly discussed.
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Mansuri, Zeeshan H., Jit H. Brahmbhatt, Roopesh R. Singhal, and Karthik Natarajan. "Altered left atrial appendage function associated with cardioembolic stroke in patients with rheumatic heart disease." International Journal of Advances in Medicine 8, no. 9 (2021): 1395. http://dx.doi.org/10.18203/2349-3933.ijam20213243.
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Background: Left atrial appendage (LAA) is usually the first site for thrombus formation in rheumatic heart disease (RHD). LAA function is altered in RHD which may predispose it to thrombus formation. The aim of this study was to determine an association between function of LAA and cardioembolic stroke.Methods:Total 132 patients with RHD were studied by means of transthoracic echocardiography and/or transesophageal echocardiography and left atrial (LA) size, LAA ejection fraction (EF) and peak flow velocities were measured. These patients were followed up for 18 months with reference to development of cardioembolic stroke.Results: Seventy nine patients had atrial fibrillation (AF), of which 34 had thrombus in LAA. Out of 53 patients with sinus rhythm, 5 had LAA thrombus. Mean LAA EF was significantly lower in patients with thrombus in LAA, so was the peak flow velocity (both variables p<0.0001). Saw tooth LAA outflow velocity pattern was visible in 30 (80%) patients with LAA thrombus versus 20 (28%) patients without LAA thrombus. Total 14 patients experienced cardioembolic stroke. Patients with cardioembolic stroke had lower mean LAA EF and peak flow velocity as compared to patients without cardioembolic stroke.Conclusions:Increased LAA size, reduced LAA EF and reduced peak flow velocity are associated with increased risk of cardioembolic stroke. LAA evaluation should be mandatory in deciding treatment strategies in patients with RHD and AF.
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Sakakibara, Y., and J. Iwamoto. "Oscillation of Impinging Jet with Generation of Acoustic Waves." International Journal of Aeroacoustics 1, no. 4 (2002): 385–402. http://dx.doi.org/10.1260/147547202765275970.
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This paper presents an oscillatory phenomenon of the underexpanded jet which issues from a convergent nozzle and impinges on a flat plate perpendicularly. As the characteristics of the generating noise deeply depend on the oscillation of the impinging jet, the flow field is visualized using the shadowgraph method and the pressure on the plate is measured to classify the oscillation modes for different parameters such as the nozzle pressure ratio and the distance between the nozzle and the plate. For the comparison, the jet is numerically simulated using Total Variation Diminishing (TVD) scheme under the assumption of the non-viscous flow. Simulating the impinging main jet and the radial wall jet on the plate separately, the sound waves propagating around the jet are shown and the frequency of the oscillation for each jet is tested. The wall-jet oscillation which is caused by the small vortices from the main jet occurs at high frequency when the nozzle-plate distance is comparatively small, while the main-jet oscillation induced by the grown vortices are shown to generate at large nozzle-plate spacing and the frequencies under such condition have well-known saw-tooth characteristics. With the correlation of pressure on the plate, three types of the oscillation – axisymmetric mode, whirling mode and non-regular pattern – are shown.
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Naqvi, Haidlir, Muhammad Hafizhuddin Hilman, and Bayu Anggorojati. "Fine Tuning of Interval Configuration for Deep Reinforcement Learning Based Congestion Control." Jurnal Ilmu Komputer dan Informasi 16, no. 2 (2023): 151–61. http://dx.doi.org/10.21609/jiki.v16i2.1159.
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It is apparent that various internet services in today’s digital ecosystem effectuate different types of networks’ quality of services (QoS) requirements. This condition, in fact, adds another level of complexity to the current network congestion control protocols. Therefore, it drives the adoption of deep reinforcement learning to improve the protocols’ adaptability to the dynamic networks’ QoS requirements. In this case, the state-of-the-art works on congestion control protocols, formulate the markov decision process (MDP) by transforming the congestion control pattern from the saw tooth congestion window to the staircase sending rate per-interval cycles. This approach treats congestion control as a sequential decision-making process that fits reinforcement learning. However, the interval configuration parameter that gives the optimum QoS has not been empirically studied. In this work, we present an extensive study on various interval configuration parameters for the deep reinforcement learning-based congestion control agent. Our work shows that various interval configuration, which consists of the RTT estimator and the n parameter, results in different QoS. The experiment shows that the RTTjk has significantly higher throughput than RTTewma and RTTmin−filtered in various network conditions. Furthermore, we found that the RTTjk with n = 2.0 is superior to other configurations in almost all networking scenarios. Whereas the RTTjk with n = 1.0 is optimal for a network environment with fixed bandwidth scenario.
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Drew, J. E., M. Monguió, and N. J. Wright. "Proper motions of OB stars in the far Carina Arm." Monthly Notices of the Royal Astronomical Society 508, no. 4 (2021): 4952–68. http://dx.doi.org/10.1093/mnras/stab2905.
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ABSTRACT In large-scale maps of the Galactic disc, the Carina Arm stands out as a clear spiral feature, hosting prominent star clusters and associations rich in massive stars. We study the proper motions of 4199 O and early B most likely in the far Carina Arm, at distances mainly in excess of 4 kpc from the Sun, within the sky region, 282° &lt; ℓ &lt; 294° and −3° &lt; b &lt; +1° (Galactic coordinates). The sample is constructed by extending an existing blue-selected catalogue, and cross-matching with Gaia EDR3 astrometry. The observed pattern of proper motions is modulated into a saw-tooth pattern, with full amplitude approaching 1 mas yr−1, recurring roughly every 2–3 degrees of longitude (200–300 pc at the median OB-star distance of 5.8 kpc). Kinematic perturbation of underlying circular rotation is most likely present. The data also reveal a moving group containing &gt;50 OB stars at ℓ ∼ 286°, b ∼ −1.4° behind the main run of the far arm. An analysis of relative proper motions is performed that yields an incidence of runaway O stars of at least 10 per cent (potentially &gt;20 per cent when full space motions become available). To map where runaways have run away from, we set up simulations for the region that assume linear trajectories and test for trajectory impact parameter in order to identify likely ejection hot spots. We find the method currently gives good results for times of flight of up to ∼4 Myr. It shows convincingly that only NGC 3603 and Westerlund 2 have ejected OB stars in significant numbers. Indeed, both clusters have experienced intense spells of ejection between 0.6–0.9 and 0.5–0.8 Myr ago, respectively.
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Weng, Hsing-Yu, Anna S. Cohen, Christoph Schankin, and Peter J. Goadsby. "Phenotypic and treatment outcome data on SUNCT and SUNA, including a randomised placebo-controlled trial." Cephalalgia 38, no. 9 (2017): 1554–63. http://dx.doi.org/10.1177/0333102417739304.
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Background Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) are two rare headache syndromes classified broadly as Trigeminal Autonomic Cephalalgias (TACs). Methods Here, 65 SUNCT (37 males) and 37 SUNA (18 males) patients were studied to describe their clinical manifestations and responses to treatment. Results Pain was almost always unilateral and side-locked. There were three types of attack: Single stabs, stab groups, and a saw-tooth pattern, with some patients experiencing a mixture of two types. As to cranial autonomic symptoms, SUNA patients mainly had lacrimation (41%) and ptosis (40%). Most cases of the two syndromes had attack triggers, and the most common triggers were touching, chewing, or eating for SUNCT, and chewing/eating and touching for SUNA. More than half of each group had a personal or family history of migraine that resulted in more likely photophobia, phonophobia and persistent pain between attacks. For short-term prevention, both syndromes were highly responsive to intravenous lidocaine by infusion; for long-term prevention, lamotrigine and topiramate were effective for SUNCT, and lamotrigine and gabapentin were efficacious in preventing SUNA attacks. A randomized placebo-controlled cross-over trial of topiramate in SUNCT using an N-of-1 design demonstrated it to be an effective treatment in line with clinical experience. Conclusions SUNCT and SUNA are rare primary headache disorders that are distinct and very often tractable to medical therapy.
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Ikeda, Takehiko, Jin-Soo Kim, Daniel I. Sessler, Chiharu Negishi, Minang Turakhia, and Renee Jeffrey. "Isoflurane Alters Shivering Patterns and Reduces Maximum Shivering Intensity." Anesthesiology 88, no. 4 (1998): 866–73. http://dx.doi.org/10.1097/00000542-199804000-00004.
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Background Shivering can be characterized by its threshold (triggering core temperature), gain (incremental intensity increase with further core hypothermia), and maximum response intensity. Isoflurane produces a clonic muscular activity that is not a component of normal shivering. To the extent that clonic activity is superimposed on normal thermoregulatory shivering, the gain of shivering might be increased during isoflurane anesthesia. Conversely, volatile anesthetics decrease systemic oxygen consumption and peripherally inhibit skeletal muscle strength, which might limit maximum intensity despite central activation. The purpose of the present study was, therefore, to evaluate the effect of isoflurane shivering patterns and the gain and maximum intensity of shivering. Methods Ten volunteers were each studied in two separate protocols: (1) control (no drug) and (2) 0.7% end-tidal isoflurane. On each day, the mean skin temperature was maintained at 31 degrees C. Core temperature was then reduced by infusion of cold fluid until shivering intensity no longer increased. The core temperature triggering the initial increase in oxygen consumption defined the shivering threshold. The gain of shivering was defined by the slope of the core temperature versus oxygen consumption regression. Pectoralis and quadriceps electromyography was used to evaluate anesthetic-induced facilitation of clonic (5-7 Hz) muscular activity. Results Isoflurane significantly decreased the shivering threshold from 36.4 +/- 0.3 to 34.2 +/- 0.8 degrees C. The increase in oxygen consumption was linear on the control day and was followed by sustained high-intensity activity. During isoflurane administration, shivering was characterized by bursts of intense shivering separated by quiescent periods. Isoflurane significantly increased the gain of shivering (as calculated from the initial increase), from -684 +/- 266 to -1483 +/- 752 ml x min(-1) x degrees C(-1). However, isoflurane significantly decreased the maximum intensity of shivering, from 706 +/- 144 to 489 +/- 80 ml/min. Relative electromyographic power in frequencies associated with clonus increased significantly when the volunteers were given isoflurane. Conclusions These data indicate that isoflurane anesthesia markedly changes the overall pattern of shivering during progressive hypothermia from a linear increase to an unusual saw-tooth pattern. They further suggest that clonic muscular activity combines with shivering to increase the initial gain of shivering during isoflurane anesthesia, but that isoflurane peripherally inhibits the maximum expression of shivering.
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Awan, Ifra Zulqarnain, Rehana Niazi, Nazeer Ahmad, Soyba Nazir, Komal Javed, and Samim Khalil. "Effects of Chest Physiotherapy for Removal of Mucus Secretions Among Mechanically Ventilated Patients in Intensive Care Unit." Healer Journal of Physiotherapy and Rehabilitation Sciences 3, no. 6 (2023): 569–77. https://doi.org/10.55735/hjprs.v3i6.156.
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Background: A mechanical ventilator is used to help the patient breathes when he cannot breathe on his own due to severe illness. Chest physiotherapy techniques like percussion, postural drainage, vibrations and suctioning of secretions help to manage the retained secretions and clear secretions, improve oxygenation and prevent pulmonary complications. Objective: To determine the effects of chest physiotherapy for the removal of retained secretions among mechanically ventilated patients in the intensive care unit. Methods: This quasi-experimental study was carried out on a sample of 110 mechanically ventilated patients, using non-probability convenient sampling. The peak inspiratory pressure, tidal volume, pulse oximetric saturation, amount of secretions removed by suctioning, respiratory sounds and saw tooth pattern were assessed before and after treatment. The treatment technique used was percussion along with postural drainage positioning and suctioning. The quantitative variables were presented as mean, standard deviation, range and histogram. Normality was checked by Kolmogorov Smirnov test. The categorical variables were evaluated as percentages, frequencies, cross tabulation, bar and pie charts. An alpha level of 0.05 was chosen for significance. Data were analyzed by using a parametric test (paired-sample t-test), Pearson chi-square test and Fisher’s exact test. Results: By using paired sample t-test, the results of the present study showed that the difference in pre-test and post-test values of peak inspiratory pressure, tidal volume and oxygen saturation were statistically significant (p-value=0.000). The mean score of secretions volume removed during suctioning pre-test was 73.66±92.60 and post-test was 87.18±103.86. Analysis showed that there is an association between pre-test and post-test respiratory sounds and sawtooth patterns (p-value=0.00). Conclusion: This study showed that after chest physiotherapy, more secretions were removed by suctioning, pulse oximetric saturation and tidal volume were improved and significant change in peak inspiratory pressure was found. Respiratory sounds and sawtooth patterns were absent after chest physiotherapy.
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Villagrán, Edwin Andrés, and Carlos Ricardo Bojacá. "Effects of surrounding objects on the thermal performance of passively ventilated greenhouses." Journal of Agricultural Engineering 50, no. 1 (2019): 20–27. http://dx.doi.org/10.4081/jae.2019.856.
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The growing expansion of protected horticulture in many regions is occurring around densely populated areas where land for agriculture is scarce, expensive or is used for other purposes. Inexpensive plastic passively ventilated greenhouses are the common choice for protected cultivation in these developing regions. The objective of this work was to analyse the effect of surrounding constructions and natural obstacles on the thermal performance of two naturally ventilated greenhouses. A saw tooth type greenhouse (TCG), typical for Colombian production, and an optimised greenhouse (OG) alternative with greater ventilation areas were analysed using computational fluid dynamics (CFD) with and without the surrounding objects of a real environment. The results showed that air exchange rate of a greenhouse with restricted ventilation areas are greatly reduced when neighbouring objects are high enough. This ventilation restriction is intensified under low wind speed conditions. The temperature gradients of the OG greenhouse were lower than those of the TCG scenarios due to the increased ventilation rates. The rooftop ventilation index for the OG greenhouse was increased by 65% with respect to the TCG greenhouse index, resulting in a direct effect on the ventilation rates. An improved air exchange with the outside can be reached by increasing the greenhouse ventilation areas, especially the roof vents, to overcome the airflow restrictions imposed by the surrounding environment. This simulation exercise was validated with field temperature data collected for a real OG prototype built in the Bogota plateau, with results showing a similar pattern for the internal temperature gradient as exhibited by the CFD model.
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Zhang, Qi-Bin, and René I. Alfaro. "Periodicity of Two-Year Cycle Spruce Budworm Outbreaks in Central British Columbia: A Dendro-Ecological Analysis." Forest Science 48, no. 4 (2002): 722–31. http://dx.doi.org/10.1093/forestscience/48.4.722.
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Abstract An outbreak of the two-year cycle budworm (Choristoneura biennis Freeman) has caused defoliation damage to interior spruce (Picea engelmannii Parry × P. glauca (Moench)) and subalpine fir (Abies lasiocarpa [Hook.] Nutt.) forests of north central British Columbia for more than 10 yr and was ongoing in 1999. A sample of 429 increment cores from spruce, subalpine fir, and lodgepole pine (Pinus contorta var. latifolia Engelm.) was collected in areas of chronic defoliation, and used in a dendro-ecological study. The objective was to develop accurately dated ring-width chronologies of each species and, by comparing growth rates of the budworm host tree species (spruce and fir) with those of the nonhost pine, to determine the past history of budworm outbreaks in the region. This history would help in estimation of the potential duration and severity of the current outbreak in the region.Four periods of decade-long reduced growth attributable to budworm defoliation were identified in the increment cores from both spruce and subalpine fir. These occurred in the mid-1890s to the early 1900s, the mid-1920s to the mid-1930s, the 1950s to the early 1960s, and the late 1980s to present (1999). Outbreaks recurred approximately every 32 yr. The reduced growth period, indicative of past outbreaks, consisted of a growth reduction phase lasting 7 to 11 yr in which rings generally exhibited a pattern of alternating wide and narrow rings (a “saw-tooth” pattern). This pattern was attributed to the biennial nature of the life cycle of this budworm, in which severe damage is caused every other year. The growth reduction phase was followed by a growth recovery phase lasting 3 to 5 yr in which ring-width gradually returned to pre-outbreak levels. Thus, the entire growth loss period could last from 10 to 16 yr and cause an average annual loss in radial increment from 16 to 21%. The 32 yr cycle of outbreak recurrence was attributed to changes in forest structure in which the forest evolves from a nonsusceptible to a susceptible state as the proportion of subalpine fir present in the upper canopy increases relative to the spruce component. A 2 yr cycle budworm outbreak will selectively remove the subalpine fir component returning the forest to a less susceptible state. It was concluded that the 2 yr cycle budworm is an important disturbance agent of northern British Columbia forests causing significant growth loss. FOR. SCI. 48(4):722–731.
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Annamalai, Kalyan. "Breathing Planet Earth: Analysis of Keeling’s Data on CO2 and O2 with Respiratory Quotient (RQ), Part I: Global Respiratory Quotient (RQGlob) of Earth." Energies 17, no. 2 (2024): 299. http://dx.doi.org/10.3390/en17020299.
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In biology, respiratory quotient (RQ) is defined as the ratio of CO2 moles produced per mole of oxygen consumed. Recently, Annamalai et al. applied the RQ concept to engineering literature to show that CO2 emission in Giga Tons per Exa J of energy = 0.1 ∗ RQ. Hence, the RQ is a measure of CO2 released per unit of energy released during combustion. Power plants on earth use a mix of fossil fuels (FF), and the RQ of the mix is estimated as 0.75. Keeling’s data on CO2 and O2 concentrations in the atmosphere (abbreviated as atm., 1991–2018) are used to determine the average RQGlob of earth as 0.47, indicating that 0.47 “net” moles of CO2 are added to which means that there is a net loss of 5.6 kg C(s) from earth per mole of O2 depleted in the absence of sequestration, or the mass loss rate of earth is estimated at 4.3 GT per year. Based on recent literature on the earth’s tilt and the amount of water pumped, it is speculated that there could be an additional tilt of 2.7 cm over the next 17 years. While RQ of FF, or biomass, is a property, RQGlob is not. It is shown that the lower the RQGlob, the higher the acidity of oceans, the lesser the CO2 addition to atm, and the lower the earth’s mass loss. Keeling’s saw-tooth pattern of O2 is predicted from known CO2 data and RQGlob. In Part II, the RQ concept is expanded to define energy-based RQGlob,En, and adopt the CO2 and O2 balance equations, which are then used in developing the explicit relations for CO2 distribution amongst atm., land, and ocean, and the RQ-based results are validated with results from more detailed literature models for the period 1991–2018.
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MANRUBIA, SUSANNA C., and ALEXANDER S. MIKHAILOV. "SYNCHRONIZATION AND CLUSTERING IN COUPLED SAW-TOOTH MAPS." International Journal of Bifurcation and Chaos 10, no. 10 (2000): 2465–78. http://dx.doi.org/10.1142/s0218127400001602.
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We consider ensembles of saw-tooth maps modified by adding a nonlinear term. The dynamics of an individual map is intermittent. Our numerical investigations show that the globally coupled ensemble can display asynchronous chaotic oscillations, coherent two-cluster collective behavior and complete mutual synchronization, depending on the coupling intensity. Circular arrays of these intermittent maps with a finite interaction radius support a variety of complex patterns, including spatial dynamic domains and traveling waves.
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Dr., Urma Saher Dr. Syeda Zakia Batool Dr. Mujahid Hassan. "ATRIAL ARRHYTHMIAS INCIDENCE (ATRIAL FIBRILLATION "AFL", MULTIFOCAL ATRIAL TACHYCARDIA "MAT" & ATRIAL FLUTTER "AF") IN COPD CASES." INDO AMERICAN JOURNAL OF PHARMACEUTICAL SCIENCES 05, no. 09 (2018): 9192–96. https://doi.org/10.5281/zenodo.1439038.
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<strong><em>Objectives: </em></strong><em>We aimed to assess the </em><em>atrial arrhythmias frequency that includes atrial flutter, atrial fibrillation and multifocal atrial tachycardia in the COPD patients.</em> <strong><em>Methodology: </em></strong><em>We included a total of 240 COPD (</em><em>Chronic Obstructive Pulmonary Disease) patients in our research which were carried out at Sir Ganga Ram Hospital, Lahore from March 2016 to April 2017. We started research protocols after securing an informed consent from the research participants and explained all the details to the research participants. Confidentiality was also maintained throughout the research. Address, age and gender were included about the demographic data and all the outcomes were recorded on a predesignated Performa. ECG was carried out to observe an absence or presence of irregular rhythm, p-waves, irregular PP interval, regular rhythm and arterial activity Saw-tooth pattern in the ECG leads. Every outcome was recorded for further analysis and record keeping.</em> <strong><em>Results: </em></strong><em>The age bracket of (40 – 55) years was reported in 111 patients (46.25%); whereas 129 patients were in the age bracket of (56 – 70) years with a mean age of (56.23 ± 8.19) years. We included 134 males (55.83%) and 106 females (44.17%). Disease duration was reported as (1 – 2) years in 142 patients (59.17%); whereas, 98 patients had a duration of more than two years (40.83%). Atrial arrhythmias frequency was reported in 22 cases (9.17%) who suffered from COPD, 53 patients had Atrial flutter (22.8%) and 31) patients had Multifocal atrial tachycardia (12.92%).</em> <strong><em>Conclusion: </em></strong><em>It is concluded through research outcomes that atrial arrhythmias frequency was high in the COPD patients. Which is why every COPD case is to be examined for atrial arrhythmias. It is also important to keep a surveillance to be informed about the disease occurrence.</em> <strong><em>Keywords</em></strong><em>: Atrial Arrhythmias, COPD (Chronic Obstructive Pulmonary Disease), Atrial Flutter and Multifocal Atrial Tachycardia.</em>
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Rini, Brian I., Laura S. Wood, Paul Elson, et al. "A phase II study of intermittent sunitinib (S) in previously untreated patients (pts) with metastatic renal cell carcinoma (mRCC)." Journal of Clinical Oncology 31, no. 15_suppl (2013): 4515. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.4515.
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4515 Background: S as initial treatment in mRCC is limited by balancing acute and chronic toxicity with clinical benefit. Pre-clinical and retrospective clinical data support that extended treatment breaks are feasible without a reduction in efficacy. Methods: Pts with treatment-naïve clear cell mRCC were enrolled on a prospective phase II trial and initially treated with 4 cycles of S (50 mg 4/2). Pts with ≥ 10% reduction in tumor burden (TB) following 4 cycles had S held, with CT scans approximately every 10 weeks. S was re-initiated for 2 cycles in those pts with an increase in TB by ≥ 10% and again held with ≥ 10% TB reduction. This intermittent S dosing continued until RECIST-defined disease progression while on S. The primary objective was feasibility of intermittent S, defined as the proportion of eligible pts who underwent intermittent therapy. The alternative hypothesis was a feasibility of > 80% vs. a null hypothesis of < 50% (a=0.05; power 80%). Results: Thirty-six pts were enrolled; 70% male, median age 60, 95% PS 0/1 and 32% favorable/65% intermediate by Heng criteria. Twenty pts were eligible for intermittent therapy and all pts (100%) entered the intermittent phase. Pts were not eligible for intermittent S due to PD (n=13); toxicity (n=1) or w/d of consent (n=2) prior to end of cycle #4. Sixteen pts (80%) had ≥ 10% TB increase off S with a median (range) increase of 1.5 cm (1.1-2.5) compared to the TB immediately prior to stopping S, considering all off periods.Four pts did not have ≥ 10% TB increase off S (3 pts after the 1st off period; off for 12, 8 and 5 months to date and 1 pt after the 2nd off period; off for 8 months prior to restarting S). Most pts exhibited a stable saw tooth pattern of TB reduction on S and TB increase off S. No pt had RECIST-defined PD while on S, but 2 pts were taken off extended breaks due to gradual TB increase over time, and 1 pt developed new CNS mets during the 2nd off period.The objective response rate was 53%. Toxicity was typical for S and completely resolved during treatment breaks. Conclusions: S dosing with periodic extended time off drug is feasible and associated with reduction in toxicity during the off periods. Clinical efficacy does not appear to be compromised. Clinical trial information: NCT01158222.
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Meynadier, Laure, and Jean-Pierre Valet. "Post-depositional realignment of magnetic grains and asymmetrical saw-tooth patterns of magnetization intensity." Earth and Planetary Science Letters 140, no. 1-4 (1996): 123–32. http://dx.doi.org/10.1016/0012-821x(96)00018-0.
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