Which technique is better to place a manoeuvrable vacuum extractor cup on the flexion point? Vacca vs. Bird technique

2020 ◽  
Vol 48 (7) ◽  
pp. 694-699
Author(s):  
Marcos Javier Cuerva ◽  
Jose Ángel Espinosa ◽  
Silvia Barras ◽  
Silvia Gonzalez-Cerron ◽  
Faride Ojeda ◽  
...  
Keyword(s):  
Simulation Model ◽  
Parietal Bone ◽  
Occipital Bone ◽  
Application Technique ◽  
Vacuum Extractor ◽  
Vertical Distance ◽  
Lateral Distance ◽  
The Mean

AbstractObjectivesThe purpose of this study is to compare the vacuum extractor cup application technique described by Bird vs. the technique described by Vacca on a simulation model.MethodsSix obstetricians participated in the study. Each obstetrician performed eight vacuum assisted deliveries using the Bird technique and eight vacuum assisted deliveries using the Vacca 5-Steps technique.ResultsA total of 96 vacuum assisted deliveries were performed. The mean distance from the centre of the cup to the flexion point was 1.78±0.96 cm for the Bird technique and 1.05±0.60 cm for the Vacca technique (p<0.001). The lateral distance (over the parietal bone) was 1.16±0.69 cm for the Bird technique and 0.66±0.52 cm for the Vacca technique (p<0.001). The vertical distance (towards the frontal or occipital bone) was 1.12±1.02 cm for the Bird technique and 0.67±0.55 cm for the Vacca technique (p=0.009). In occipito anterior positions, there were no significant differences between both techniques.ConclusionsThe Vacca technique was better in transverse and posterior positions.

scholarly journals The effect of nano-hydroxyapatite/chitosan scaffolds on rat calvarial defects for bone regeneration

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Emmanouil Chatzipetros ◽  
Spyros Damaskos ◽  
Konstantinos I. Tosios ◽  
Panos Christopoulos ◽  
Catherine Donta ◽  
...  
Keyword(s):  
Bone Regeneration ◽  
Mean Value ◽  
Parietal Bone ◽  
Female Rats ◽  
Sprague Dawley ◽  
Post Surgery ◽  
Group A ◽  
The Mean ◽  
Group B ◽  
The Right

Abstract Background This study aims at determining the biological effect of 75/25 w/w nano-hydroxyapatite/chitosan (nHAp/CS) scaffolds on bone regeneration, in terms of fraction of bone regeneration (FBR), total number of osteocytes (Ost), and osteocyte cell density (CD), as well as its biodegradability. Methods Two critical-size defects (CSDs) were bilaterally trephined in the parietal bone of 36 adult Sprague-Dawley rats (18 males and 18 females); the left remained empty (group A), while the right CSD was filled with nHAp/CS scaffold (group B). Two female rats died postoperatively. Twelve, 11, and 11 rats were euthanized at 2, 4, and 8 weeks post-surgery, respectively. Subsequently, 34 specimens were resected containing both CSDs. Histological and histomorphometric analyses were performed to determine the FBR, calculated as [the sum of areas of newly formed bone in lateral and central regions of interest (ROIs)]/area of the original defect, as well as the Ost and the CD (Ost/mm2) in each ROI of both groups (A and B). Moreover, biodegradability of the nHAp/CS scaffolds was estimated via the surface area of the biomaterial (BmA) in the 2nd, 4th, and 8th week post-surgery. Results The FBR of group B increased significantly from 2nd to 8th week compared to group A (P = 0.009). Both the mean CD and the mean Ost values of group B increased compared to group A (P = 0.004 and P < 0.05 respectively). Moreover, the mean value of BmA decreased from 2nd to 8th week (P = 0.001). Conclusions Based on histological and histomorphometric results, we support that 75/25 w/w nHAp/CS scaffolds provide an effective space for new bone formation.

scholarly journals Morphologic and Osteometric Analysis of the Skull of Markhoz Goat (Iranian Angora)

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Nader Goodarzi ◽  
Toraj Shah Hoseini
Keyword(s):  
Foramen Magnum ◽  
Parietal Bone ◽  
Frontal Bone ◽  
Occipital Bone ◽  
Cheek Tooth ◽  
Frontal Surface ◽  
Infraorbital Foramen ◽  
Skull Length ◽  
Cranial Index

This study provides some comprehensive osteometric and morphologic descriptions of the skull region of the Markhoz goat. Totally, 17 osteometric parameters of eight skulls of Markhoz goat were measured and expressed as mean ± SD. A skull length of18.67±0.66, a cranial length of11.1±0.38, a facial length of10.23±0.76, a skull index of47.77±1.96, a cranial index of54.04±2.29, a facial index of100.77±6.85and a foramen magnum index of89.32±14.1were recorded. Morphologically frontal bone did not constitute the caudal extent of frontal surface; rather it was formed by the parietal bone. There were two supraorbital foramina in both sides. The prominent facial tuberosity lies dorsally to the 3rd cheek tooth. The infraorbital foramen was single on either side which was located directly dorsally to the junction of the first and second upper premolar. The orbits were round and complete and located on a frontolateral oblique plane. The basilar part of the occipital bone was surrounded by two pairs of muscular tubercles with similar size. The temporal line was continuous of the temporal crest and ran over the parietal bone. In conclusion, the morphologic and osteometric data of Markhoz goat are comparable to other ruminants.

scholarly journals Poynting-Robertson Effect and Collisions in the Interplanetary Dust Cloud

1980 ◽  
Vol 90 ◽  
pp. 299-302
Author(s):  
Jan Trulsen ◽  
Arild Wikan
Keyword(s):  
Simulation Model ◽  
Dust Cloud ◽  
Dynamical Evolution ◽  
Interplanetary Dust ◽  
Collision Time ◽  
The Mean ◽  
The Individual ◽  
Individual Grains

A simulation model has been developed to study the results of the Poynting-Robertson (PR) effect and collisions on the dynamical evolution of an interplanetary dust cloud. Fragmentational and accretional effects are neglected. With a mean free collision time of the order of the PR lifetime collisional effects become of importance. As the individual grains still spiral inwards collisions act to make the mean eccentricity and inclination of the grain orbits both decrease at comparable rates, giving rise to an expanding fan shaped dust cloud.

scholarly journals Quantitive Study on Some Aspect of Occipital Area in Domestic Cat (Felis catus)

2016 ◽  
pp. 18-21 ◽  
Author(s):  
M Uddin ◽  
ME Hossain ◽  
MS Islam ◽  
MB Hossain ◽  
KN Islam
Keyword(s):  
Foramen Magnum ◽  
Felis Catus ◽  
Occipital Bone ◽  
Domestic Cat ◽  
Clinical Anatomy ◽  
Significant Difference ◽  
The Mean ◽  
Level Of Significance ◽  
Occipital Condyles ◽  
Classification And Treatment

This study was planned to investigate some aspects of the morphometric characteristics of the occipital bone and foramen megnum in domestic cat (Felis catus). Twenty adult domestic cat including 10 males and 10 female cats were euthanized using diazepam (@ 20 mg/kg) and their skulls were macerated to give morphometric parameters. Student t-test with level of significance set at 5% (p < 0.05) was used to analyze the obtained values. The height of occipital triangle, width of occipital condyles, width of jugular process were significantly larger in male than female. The mean height and width of the foramen magnum were 1.32 ± 0.09 cm and 1.35 ± 0.08 cm, respectively, while the foramen index was below 100 at 90.72 ± 4.93. Parameters for the foramen magnum index showed significant difference between both sexes at p < 0.05. The foramen magnum showed shape variations and there were multiple hypoglossal foramina in over 80% of the cats. The morphometric values of the occipital bone and foramen magnum and clinical anatomy of the occipital region of the domestic cats provide an important baseline for further research in this field and could help in the better diagnosis, classification, and treatment of diseases related to this region and serve as a future reference defining an anatomic range.International Journal of Natural Sciences (2013), 3(1-4) 18-21

Differential pressure in shunt therapy: investigation of position-dependent intraperitoneal pressure in a porcine model

2013 ◽  
Vol 12 (6) ◽  
pp. 575-581 ◽  
Author(s):  
Florian Baptist Freimann ◽  
Jens Ötvös ◽  
Sascha Santosh Chopra ◽  
Peter Vajkoczy ◽  
Stefan Wolf ◽  
...  
Keyword(s):  
Body Position ◽  
Pressure Sensors ◽  
Differential Pressure ◽  
Intraperitoneal Pressure ◽  
Vertical Distance ◽  
Ventriculoperitoneal Shunting ◽  
Hydrostatic Force ◽  
The Mean ◽  
The Difference

Object The differential pressure between the intracranial and intraperitoneal cavities is essential for ventriculoperitoneal shunting. A determination of the pressure in both cavities is decisive for selecting the appropriate valve type and opening pressure. The intraperitoneal pressure (IPP)—in contrast to the intracranial pressure—still remains controversial with regard to its normal level and position dependency. Methods The authors used 6 female pigs for the experiments. Two transdermal telemetric pressure sensors (cranial and caudal) were implanted intraperitoneally with a craniocaudal distance of 30 cm. Direct IPP measurements were supplemented with noninvasive IPP measurements (intragastral and intravesical). The IPP was measured with the pigs in the supine (0°), 30°, 60°, and vertical (90°) body positions. After the pigs were euthanized, CT was used to determine the intraperitoneal probe position. Results With pigs in the supine position, the mean (± SD) IPP was 10.0 ± 3.5 cm H2O in a mean vertical distance of 4.5 ± 2.8 cm to the highest level of the peritoneum. The difference between the mean IPP of the cranially and the caudally implanted probes (Δ IPP) increased according to position, from 5.5 cm H2O in the 0° position to 11.5 cm H2O in the 30° position, 18.3 cm H2O in the 60° position, and 25.6 cm H2O in the vertical body position. The vertical distance between the probe tips (cranially implanted over caudally implanted) increased 3.4, 11.2, 19.3, and 22.3 cm for each of the 4 body positions, respectively. The mean difference between the Δ IPP and the vertical distance between both probe tips over all body positions was 1.7 cm H2O. Conclusions The IPP is subject to the position-dependent hydrostatic force. Normal IPP is able to reduce the differential pressure in patients with ventriculoperitoneal shunts.

Effect of group behavior on pedestrian choice for vertical walking facilities

2020 ◽  
Vol 34 (07) ◽  
pp. 2050056
Author(s):  
Yongxing Li ◽  
Wenjing Wu ◽  
Xin Guo ◽  
Yu Lin ◽  
Shiguang Wang
Keyword(s):  
Support Vector Machine ◽  
Cellular Automata ◽  
Simulation Model ◽  
Choice Model ◽  
Group Behavior ◽  
Support Vector ◽  
Floor Field ◽  
The Mean ◽  
Simulation Results ◽  
Pedestrian Simulation

Analyzing the characteristics of group behavior, leader-follower model which adopts dynamic group floor field to represent the attraction in a group is used to model pedestrian group behavior. Pedestrian choice model of vertical walking facilities based on support vector machine (SVM) with the effect of group behavior is established. Fusing pedestrian choice model of vertical walking facilities and leader-follower model into a cellular automata (CA)-based pedestrian simulation model, we simulate the pedestrian choice process for vertical walking facilities with the effect of group behavior. The simulation results indicate that with the effect of group behavior, the choice results of some pedestrians are changed, and the efficiency of pedestrians passing is reduced. To some extent, the efficiency of pedestrians passing is improved with the mean distribution of luggage in each group.

Using discrete-event simulation to increase the efficiency of point of distribution sites

2018 ◽  
Vol 16 (5) ◽  
pp. 279
Author(s):  
Patrick Glass, MS, MPH ◽  
Eric Dietz, PhD ◽  
Pamela Aaltenon, PhD, RN
Keyword(s):  
Computer Simulation ◽  
Simulation Model ◽  
Discrete Event ◽  
T Test ◽  
Computer Simulation Model ◽  
Group A ◽  
The Mean ◽  
The Difference ◽  
Group B ◽  
Mean Time

Objective: The objective of this research was to develop a computer simulation model that will provide the most optimal allocation of resources for a point of distribution (POD) site.Design: A baseline assessment was conducted by participants establishing POD sections with no guidance from the investigator. A computer model was built with four stations: triage, registration, screening, and dispensing. The information from the computer simulation was used to design the allocation of volunteers for the experimental group. Once the data were collected, a two-sample t test was used to determine the significance of the difference between the average times of the two groups to complete the POD.Setting: The POD site was conducted indoors with volunteers acting as patients, and volunteer nursing students, and pharmacy students acting as POD workers. Volunteers were divided into two groups, group B, experimental and group A, control. Time was recorded using a digital time-stamp at the beginning and at the end of the POD.Interventions: The researcher inputted the total number of volunteers into the model, and the model generated the most applicable ratio for distribution of human capital: a one-to-one ratio of screeners to dispensers. Main outcome measures: The mean time for Group A was 4.55 minutes (95% CI: 4.27, 4.83). The mean time for group B was 3.05 minutes (95% CI: 2.79, 3.31). A two-sample t test and Analysis of Variance of these data show that the difference is meaningful (p < 0.001).Results: The results show that a discrete-event computer simulation can be used to identify the most efficient use of resources in order to decrease the amount of time that patients are required to participate.Conclusions: The discrete-event computer simulation model was found to be effective at identifying ways to increase efficiency and reduce the overall time required by patients to complete the POD.

A Simulation Model of Lake Trout Growth

1971 ◽  
Vol 28 (6) ◽  
pp. 815-819 ◽  
Author(s):  
S. R. Kerr
Keyword(s):  
Simulation Model ◽  
Growth Model ◽  
Lake Trout ◽  
Growth Efficiency ◽  
Equation System ◽  
Growth Increments ◽  
Predator Size ◽  
Mean Size ◽  
The Mean

Kerr (J. Fish. Res. Bd. Canada 28: 809–814, 1971) described an equation system based upon metabolic constraints and foraging limitations that predicts level of rations and growth efficiency as a function of the availability of the prey resource. An algorithm that extends the equation system to a growth model is described here. With reference to increasing predator size, and to the mean size and abundance of prey, the model computes successive growth increments while holding the equations to the configuration that maximizes the ratio of growth efficiency to rations. When given information on the mean size and density of prey organisms, the model accurately predicts observed patterns of lake trout growth.

Inverted-hook occipital clamp system in occipitocervical fixation

2002 ◽  
Vol 97 (1) ◽  
pp. 135-141 ◽  
Author(s):  
Alexis Faure ◽  
Ruy Monteiro ◽  
Olivier Hamel ◽  
Sylvie Raoul ◽  
Jacek Szapiro ◽  
...  
Keyword(s):  
Internal Fixation ◽  
Occipital Bone ◽  
Burr Hole ◽  
Fixation Procedure ◽  
Content Type ◽  
Occipitocervical Fixation ◽  
The Mean ◽  
Fine Print

✓ The authors describe an occipitocervical fixation procedure in which they use inverted occipital hooks inserted through a burr hole drilled in the squamous part of the occipital bone. Fifteen patients with unstable lesions of the occipitocervical junction underwent occipitocervical internal fixation. The mean follow-up period was 21 months (range 2–63 months). No implant failed, and postoperative immobilization was not required. The placement of a posterior occipitocervical graft (for which fusion is uncertain) can be avoided in certain conditions.

SIMULATION MODEL FOR THE POPULATION DYNAMICS OF THE CARROT WEEVIL, LISTRONOTUS OREGONENSIS (LECONTE) (COLEOPTERA: CURCULIONIDAE)

1991 ◽  
Vol 123 (1) ◽  
pp. 63-76 ◽  
Author(s):  
D.X. Zhao ◽  
G. Boivin ◽  
R.K. Stewart
Keyword(s):  
Population Dynamics ◽  
Simulation Model ◽  
Mortality Rates ◽  
Egg Parasitoid ◽  
Adult Density ◽  
Larval Population ◽  
Listronotus Oregonensis ◽  
The Mean ◽  
Carrot Weevil ◽  
The Impact

AbstractA simulation model was developed for the population dynamics of a carrot weevil, Listronotus oregonensis (LeConte), population on muck-grown carrots. The model includes mortality rates of eggs, larvae, and pupae for different sowing dates of carrots. It also incorporates the overwintered adult density, the temperature-dependent growth rates of the above-mentioned life stages, the age-, temperature-, and phenology-dependent oviposition rates, and the impact of an egg parasitoid, Anaphes sordidatus (Girault), on egg mortality rates. Model output was evaluated by comparing simulated results with observed results on the seasonal totals and time of population peaks of the egg and larval populations. The mean percentage differences between the simulated and observed seasonal egg totals were 3.1 ± 0.66 (SE) in 1987 and 1988, and 4.2 ± 0.05 in 1989. They were not statistically different. The mean percentage differences between the simulated and observed seasonal larval totals were 10 ± 3.33 in 1987 and 1988 and 29.8 ± 0.66 in 1989. Independent data sets (i.e. field data in 1989) showed a significant increase in the simulation error of the larval population. Sensitivity analysis indicated that A. sordidatus had a large influence on the population dynamics of L. oregonensis.

Sign in / Sign up

Export Citation Format

Share Document