The relationship between peak pressure and parameters of pulse-jet cleaning in a sintered plastic filter

Background: The relationship between turf toe and plantar foot pressures has not been extensively studied. Two hypotheses were tested in a cohort of professional American football players: first, that a history of turf toe is associated with increased peak hallucal and first metatarsophalangeal (MTP) plantar pressures; second, that decreased range of motion (ROM) of the first MTP correlates with increased peak hallucal and first MTP plantar pressures. Materials and Methods: Forty-four athletes from one National Football League (NFL) team were screened for a history of turf toe during preseason training. Dorsal passive MTP ROM and dynamic plantar pressures were measured in both feet of each player. Anatomical masking was used to assess peak pressure at the first MTP and hallux. Results: First MTP dorsiflexion was significantly lower in halluces with a history of turf toe (40.6 ± 15.1 degrees versus 48.4 ± 12.8 degrees, p = 0.04). Peak hallucal pressures were higher in athletes with turf toe (535 ± 288 kPa versus 414 ± 202 kPa, p = 0.05) even after normalizing for athlete body mass index ( p = 0.0003). Peak MTP pressure was not significantly different between the two groups tested. First MTP dorsiflexion did not correlate with peak hallucal or first MTP pressures. Conclusion: This study showed that turf toe is associated with decreased MTP motion. In addition, increased peak hallucal pressures were found. Further study is warranted to determine whether these pressures correlate with the severity of symptoms or progression of turf toe to first MTP arthritis.

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Opening Injection Pressure Consistently Detects Needle–Nerve Contact during Ultrasound-guided Interscalene Brachial Plexus Block

Anesthesiology ◽

10.1097/aln.0000000000000133 ◽

2014 ◽

Vol 120 (5) ◽

pp. 1246-1253 ◽

Cited By ~ 49

Author(s):

Jeff C. Gadsden ◽

Jason J. Choi ◽

Emily Lin ◽

Allegra Robinson

Keyword(s):

Brachial Plexus ◽

Peak Pressure ◽

Injection Pressure ◽

Interscalene Block ◽

Ultrasound Images ◽

Interscalene Brachial Plexus Block ◽

Pressure Manometer ◽

Line Pressure ◽

Plexus Block ◽

The Relationship

Abstract Background: Needle trauma may cause neuropathy after nerve blockade. Even without injection, nerve injury can result from forceful needle–nerve contact (NNC). High opening injection pressures (OIPs) have been associated with intrafascicular needle tip placement and nerve damage; however, the relationship between OIP and NNC is unclear. The authors conducted a prospective, observational study to define this relationship. Methods: Sixteen patients scheduled for shoulder surgery under interscalene block were enrolled if they had clear ultrasound images of the brachial plexus roots. A 22-gauge stimulating needle was inserted within 1 mm of the root, and 1-ml D5W injected at 10 ml/min by using an automated pump. OIP was monitored using an in-line pressure manometer and injections aborted if 15 psi or greater. The needle was advanced to displace the nerve slightly (NNC), and the procedure repeated. Occurrence of evoked motor response and paresthesia were recorded. Results: Fifteen patients had at least one clearly visible root. OIP at 1 mm distance from the nerve was less than 15 psi (mean peak pressure 8.2 ± 2.4 psi) and the 1-ml injection could be completed in all but two cases (3%). In contrast, OIP during NNC was 15 psi or greater (mean peak pressure 20.9 ± 3.7 psi) in 35 of 36 injections. Aborting the injection when OIP reached 15 psi prevented commencement of injection in all cases of NNC except one. Conclusion: High OIP (≥15 psi) consistently detected NNC, suggesting that injection pressure monitoring may be useful in preventing injection against nerve roots during interscalene block.

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The Analysis of the Influence of Perforating Parameters on the Strength Security of Perforation String

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.268-270.514 ◽

2012 ◽

Vol 268-270 ◽

pp. 514-517 ◽

Cited By ~ 1

Author(s):

Fei Xu ◽

Ming Fei Li ◽

Yi Hua Dou ◽

Fu Xiang Zhang ◽

Xiang Tong Yang

Keyword(s):

Charge Density ◽

Peak Pressure ◽

Peak Stress ◽

Contrastive Analysis ◽

Gas Well ◽

The Moment ◽

The Relationship ◽

Perforated Completion

Perforating parameters, such as charge density, charge quantity and shooting density, are the important factors that affect the strength security of perforation string. Finding out the relationship between this two and understanding the regularity has the guiding significance to avoid the perforating accidents. Based on the research about the strength security of perforation string at the moment of perforating, taking a perforated completion gas well as an example, by changing the perforating parameters and conducting the contrastive analysis and research, then gets the regularity understanding about the influence of the perforating parameters on the strength security of perforation string:When the charge density is more than 1.9g/m3, the amplification of peak pressure will slow down ,and the influence of charge density will decrease; When the charge quantity is more than 40 gram, the amplification of the peak pressure on the packer and the peak stress of tubing will slow down ,and the influence of charge quantity will decrease; When the shooting density is more than 20 hole/m, the amplification of peak will slow down, and the influence of shooting density will decrease.

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Experimental and theoretical observations on the relationship between dislocation cell size, dislocation density, residual hardness, peak pressure and pulse duration in shock-loaded nickel

Acta Metallurgica ◽

10.1016/0001-6160(78)90034-2 ◽

1978 ◽

Vol 26 (5) ◽

pp. 847-857 ◽

Cited By ~ 100

Author(s):

L.E Murr ◽

D Kuhlmann-Wilsdorf

Keyword(s):

Dislocation Density ◽

Cell Size ◽

Pulse Duration ◽

Peak Pressure ◽

Dislocation Cell ◽

Hardness Peak ◽

The Relationship ◽

Dislocation Cell Size

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Generalized Joint Laxity Associated With Increased Medial Foot Loading in Female Athletes

Journal of Athletic Training ◽

10.4085/1062-6050-44.4.356 ◽

2009 ◽

Vol 44 (4) ◽

pp. 356-362 ◽

Cited By ~ 19

Author(s):

Kim D. Barber Foss ◽

Kevin R. Ford ◽

Gregory D. Myer ◽

Timothy E. Hewett

Keyword(s):

Pressure Distribution ◽

Plantar Pressure ◽

Peak Pressure ◽

Joint Laxity ◽

Maximum Force ◽

Lower Extremity Injury ◽

Extremity Injury ◽

Plantar Pressure Distribution ◽

Generalized Joint Laxity ◽

The Relationship

Abstract The relationship between generalized joint laxity and plantar pressure distribution of the foot and the potential implications for lower extremity injury have not been studied.Context: To determine the relationship between generalized joint laxity and dynamic plantar pressure distribution. We hypothesized that individuals with greater generalized joint laxity, or hypermobility, would have greater dynamic medial midfoot pressure and loading during walking than nonhypermobile individuals.Objective: Case control.Design: Institutional biomechanics laboratory.Setting: Participants included 112 female soccer players between 11 and 21 years of age.Patients or Other Participants: Each participant was tested for generalized joint laxity using the Beighton and Horan Joint Mobility Index (BHJMI; range, 0–9) and was categorized as having either high (BHJMI score ≥4) or low (BHJMI score <4) generalized joint laxity. Peak pressure and maximum force were calculated from a dynamic, barefoot plantar pressure distribution system.Main Outcome Measure(s): Peak pressure and maximum force were greater in the 27 participants categorized as having high generalized joint laxity than in the 85 participants categorized as having low generalized joint laxity. The midfoot region exhibited greater loading in participants with high generalized joint laxity than in the other participants. We found an effect of BHJMI classification in the medial midfoot; peak pressure in the dominant (F1,109 = 11.262, P = .001) and nondominant (F1,109 = 14.32, P < .001) sides and maximum force in the dominant (F1,109 = 7.88, P = .006) and nondominant (F1,109 = 9.18, P = .003) sides were greater in the high generalized joint laxity group than in the low generalized joint laxity group.Results: Athletes classified as having high generalized joint laxity demonstrated increased midfoot loading. Delineation of risk factors for medial collapse of the foot, which include hypermobility in athletes, may help clinicians evaluate and prevent lower extremity injury with treatments, such as orthoses.Conclusions:

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Effect of Venturi Structures on the Cleaning Performance of a Pulse Jet Baghouse

Applied Sciences ◽

10.3390/app9183687 ◽

2019 ◽

Vol 9 (18) ◽

pp. 3687

Author(s):

Xingcheng Liu ◽

Henggen Shen

Keyword(s):

Arrival Time ◽

Test Bench ◽

Peak Pressure ◽

Dust Emission ◽

Cleaning Efficiency ◽

Cleaning Performance ◽

Design Changes ◽

Throat Diameter ◽

Cleaning Cycle ◽

Pulse Jet

In order to study the effect of venturi structures on the cleaning performance of a pulse jet baghouse, several cleaning tests are carried out applying the pulse jet test bench. Experiments are performed using different filter bags with venturi tubes of varying throat diameters and lengths. Peak pressure and peak pressure arrival time are selected to evaluate the cleaning efficiency under different conditions. On this basis, a series of comparative experiments are conducted between a typical venturi-type and a new venturi tube design on a semi-industrial pulse jet baghouse. The effects of the new venturi-type on baghouse cleaning performance and dust emission are studied. The results show that pulsing air pressure has a significant effect on bag-cleaning performance; the larger the throat diameter and the shorter the venturi length, the higher the peak pressure and the shorter the peak pressure arrival time. This improves the cleaning efficiency of the filter bags. The new venturi design changes the distribution of the cleaning pressure in the vicinity of the bag mouth, effectively extending the cleaning cycle and reducing the energy consumption as well as reducing the dust emission concentration of the baghouse.

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Running and Walking Foot Loading in Children Aged 4–10 Years

Journal of Applied Biomechanics ◽

10.1123/jab.2018-0379 ◽

2019 ◽

Vol 35 (4) ◽

pp. 241-246

Author(s):

Paula R. Mesquita ◽

Silvia G.R. Neri ◽

Ricardo M. Lima ◽

Eliane F. Manfio ◽

Ana C. de David

Keyword(s):

Contact Area ◽

Plantar Pressure ◽

Peak Pressure ◽

Clinical Applications ◽

Pressure Data ◽

Anthropometric Measures ◽

Foot Length ◽

Loading Patterns ◽

Foot Loading ◽

The Relationship

Although previous reports have provided normative plantar pressure data for walking in children, evaluation during running is lacking. This study aimed to compare foot loading patterns during running and walking in children aged 4–10 years. Furthermore, the relationship between running baropodometric parameters and anthropometric measures was investigated. Foot loading of 120 volunteers was evaluated during running and walking using an Emed AT-4 pressure platform. Analyses were performed for 5 anatomical regions (rearfoot, midfoot, forefoot, hallux, and lesser toes). Higher peak pressure and maximum force values were seen under most foot regions during running in comparison with walking, whereas relative contact area tended to increase only in the midfoot. Data for running indicated that aging explained less than 23% of the variance of plantar loads and contact area. Running foot loads were more associated with height, body mass, and foot length. This study’s data described plantar loads under the feet of children were greater during running. Aging was associated with little increase in running plantar loads and larger contact areas. Results may be useful as reference to characterize foot loading during running and in the development of orthoses in clinical applications or products such as sport shoes for children.

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Non-Nutritive Sucking in the Preterm Infant

American Journal of Perinatology ◽

10.1055/s-0038-1667289 ◽

2018 ◽

Vol 36 (03) ◽

pp. 268-276 ◽

Cited By ~ 8

Author(s):

Kelsey Dewey ◽

Amy Jacobsen ◽

Joan Smith ◽

Roberta Pineda

Keyword(s):

Social Factors ◽

Peak Pressure ◽

Oral Feeding ◽

Medical Complications ◽

Feeding Success ◽

Nutritive Sucking ◽

Scale Scores ◽

Postmenstrual Age ◽

Relationship Of ◽

The Relationship

Objective To identify the progression of non-nutritive sucking (NNS) across postmenstrual age (PMA) and to investigate the relationship of NNS with medical and social factors and oral feeding. Study Design Fifty preterm infants born at ≤32 weeks gestation had NNS assessed weekly starting at 32 weeks PMA with the NTrainer System. Oral feeding was assessed at 38 weeks PMA. Results There were increases in NNS bursts per minute (p = 0.005), NNS per minute (p < 0.0001), NNS per burst (p < 0.001), and peak pressure (p = 0.0003) with advancing PMA. Level of immaturity and medical complications were related to NNS measures (p < 0.05). NNS measures were not related to Neonatal Oral Motor Assessment Scale scores. Smaller weekly change in NNS peak pressure (p = 0.03; β = –1.4) was related to feeding success at 38 weeks PMA. Conclusion Infants demonstrated NNS early in gestation. Variability in NNS scores could reflect medical complications and immaturity. More stable sucking pressure across time was related to feeding success at 38 weeks PMA.

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Pressure-volume behavior of the upper airway

Journal of Applied Physiology ◽

10.1152/jappl.1986.61.3.912 ◽

1986 ◽

Vol 61 (3) ◽

pp. 912-918 ◽

Cited By ~ 32

Author(s):

J. M. Fouke ◽

J. P. Teeter ◽

K. P. Strohl

Keyword(s):

Peak Pressure ◽

Force Production ◽

Upper Airway ◽

Volume Relationship ◽

Anesthetized Dogs ◽

Cervical Trachea ◽

Force Volume ◽

Pressure Changes ◽

Upper Airway Muscles ◽

The Relationship

The study was performed to investigate the relationship between force generation and upper airway expansion during respiratory efforts by upper airway muscles. In 11 anesthetized dogs we isolated the upper airway (nasal, oral, pharyngeal, and laryngeal regions) by transecting the cervical trachea and sealing the nasal and oral openings. During spontaneous respiratory efforts the pressure within the sealed upper airway, used as an index of dilating force, decreased during inspiration. On alternate breaths the upper airway was opened to a pneumotachograph, and an increase in volume occurred, also during inspiration. Progressive hyperoxic hypercapnia produced by rebreathing increased the magnitude of change in pressure and volume. At any level of drive, peak pressure or volume occurred at the same point during inspiration. At any level of drive, volume and pressure changes increased with end-expiratory occlusion of the trachea. The force-volume relationship determined from measurements during rebreathing was compared with pressure-volume curves performed by passive inflation of the airway while the animal was apneic. The relationship during apnea was 1.06 +/- 0.55 (SD) ml/cmH2O, while the force-volume relationship from rebreathing trials was -1.09 +/- 0.45 ml/cmH2O. We conclude that there is a correspondence between force production and volume expansion in the upper airway during active respiratory efforts.

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