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.

Determination of aerobic work and power on a rope-braked cycle ergometer by direct measurement

2006 ◽  
Vol 31 (4) ◽  
pp. 392-397 ◽  
Author(s):  
Rae S. Gordon ◽  
Kathryn L. Franklin ◽  
Julien S. Baker ◽  
Bruce Davies
Keyword(s):  
Direct Measurement ◽  
Power Estimation ◽  
Cycle Ergometer ◽  
Mean Power ◽  
Physiological Assessment ◽  
Brake Force ◽  
The Mean ◽  
The Difference ◽  
Work Done

The purpose of this study was to compare the power and work outputs of a cycle ergometer using the manufacturer’s guidelines, with calculations using direct flywheel velocity and brake torque. A further aim was to compare the values obtained with those supplied by the manufacturer. A group of 10 male participants were asked to pedal a Monark 824E ergometer at a constant cadence of 60 r/min for a period of 3 min against a resistive mass of 3 kg. The flywheel velocity was measured using a tachometer. The brake force was determined by measuring the tension in the rope on either side of the flywheel. The calculated mean power was 147.45 ± 6.5 W compared with the Monark value of 183 ± 3.7 W. The difference between the methods for power estimation was 18% and was statistically significant (p < 0.01). The mean work done by the participants during the 3 min period was found to be 26 460 ± 1145 J compared with the Monark value of 33 067 ± 648 J (p < 0.01). The Monark formulae currently used to determine the power and work done by a participant overestimates the actual values required to overcome the resistance. There findings have far-reaching implications in the physiological assessment of athletic, sedentary, and diseased populations.

scholarly journals Determination of LC and LB

1995 ◽  
Vol 10 ◽  
pp. 205-205
Author(s):  
T. Fukushima
Keyword(s):  
Time Scales ◽  
Full Paper ◽  
Numerical Integrations ◽  
Best Estimate ◽  
Analytical Formulas ◽  
The Mean ◽  
The Difference ◽  
Scale Difference ◽  
Astronomical Constants

The location-independent part of TCB-TCG, the difference between the two new time scales adopted by the IAU (1992), was integrated numerically for three JPL planetary/lunar ephemerides; DE102, DE200, and DE245. The differences among these three integrations were mostly explained by the difference in the adopted constants of the ephemerides. It was shown that the post-Newtonian correction and the perturbation by asteroids are negligible except for the mean rate, LC. The comparison of these numerical integrations with the analytical formulas of Hirayama et al. (1987) and Fairhead and Bretagnon (1990) as well as their extended versions lead to the best estimate of LC asCombining this with the recent value of the geoid potential in Bursa et al. (1992), we estimated the value of LB, the scale difference between TCB and TT, asTable I summarizes these conclusions. These estimates of LC and LB are more reliable than the former values we gave (Fukushima et al. 1986). The new estimate of LB will be useful in converting the numerical values of some precisely determined astronomical constants such as AU measured in meter from those in TDB to those in TCB. Also the numerically integrated TCB-TCG, which are to be called Time Ephemeris, will be useful when converting between TCB and TDB, i.e. the time scales themselves. The full paper will be appeared in A & A with the title of Time Ephemeris.

scholarly journals Komposisi Jenis Gastropoda di Mangrove Desa Kaliwlingi dan Sawojajar, Jawa Tengah

2020 ◽  
Vol 9 (2) ◽  
pp. 167-174
Author(s):  
Erik Wijaya Kusuma ◽  
Ria Azizah Tri Nuraini ◽  
Retno Hartati
Keyword(s):  
Mangrove Forest ◽  
Diversity Index ◽  
Gastropod Species ◽  
Mangrove Area ◽  
Central Java ◽  
Mangrove Ecosystems ◽  
The Mean ◽  
The Difference ◽  
Different Characteristics

ABSTRAK : Desa Kaliwlingi dan Sawojajar mempunyai kawasan hutan mangrove dengan karakteristik berbeda. Kawasan hutan mangrove Kaliwlingi menjadi ekowisata mangrove sejak tahun 2016, sedangkan di Sawojajar merupakan kawasan mangrove alami. Perbedaan fungsi tersebut diduga dapat mempengaruhi keanekaragaman hayati yaitu salah satunya adalah gastropoda. Tujuan dari penelitian ini adalah untuk mengetahui struktur komunitas Gastropoda di ekosistem mangrove Desa Kaliwlingi dan Sawojajar, Kab.Brebes, Jawa Tengah. Pengambilan sampel dilakukan pada bulan Juni sampai Juli 2018. Penentuan titik sampling menggunakan metode purposive pada 3 stasiun dengan tiga kali pengulangan. Hasil penelitian menunjukan terdapat 2 subkelas yaitu Pulmonata dan Prosobranchiata, dengan 3 famili dan  9 spesies gastropoda dari 3 famili, yaitu Elliobidae; Cassidula aurisfelis (Elliobidae), C. nucleus (Elliobidae), Littoraria articulate (Littorinidae), L. carinifera (Littorinidae), L. melanostoma (Littorinidae), L. scabra (Littorinidae), Telescopium telescopium (Potamididae), Terebralia obtuse (Potamididae), T. palustris (Potaminidae).  Nilai kelimpahan rata-rata gastropoda Desa Kaliwlingi dan Desa Sawojajar masing-masing 20,28 dan 16,36 Ind/m². Indeks Keanekaragaman (H’) gastropoda di kawasan mangrove Desa Kaliwlingi dan Desa Sawojajar termasuk ke dalam kategori rendah ke tinggi, sedangkan indeks keseragamannya  berkategori rendah.  Tidak ada jenis gastropod yang mendominasi di kawasan mangrove Kaliwlingi dan Sawojajar, dengan pola sebaran gastropoda mengelompok.ABSTRACT: Kaliwlingi and Sawojajar villages have mangrove forest areas with different characteristics. The Kaliwlingi mangrove forest area has been established as mangrove ecotourism since 2016, while in Sawojajar it is a natural mangrove area. The difference in function is thought to affect biodiversity, one of which is gastropods. The purpose of this study was to determine the structure of the Gastropoda community in the mangrove ecosystems of Kaliwlingi and Sawojajar Villages, Kab. Brebes, Central Java. Sampling was conducted in June to July 2018. Determination of the sampling points using purposive methods at 3 stations with three repetitions. The results showed that there were 2 subclasses, namely Pulmonata and Prosobranchiata, with 3 families and 9 gastropod species from 3 families, namely Elliobidae; Cassidula aurisfelis (Elliobidae), C. nucleus (Elliobidae), Littoraria articulate (Littorinidae), L. carinifera (Littorinidae), L. melanostoma (Littorinidae), L. scabra (Littorinidae), Telescopium telescopium (Potamebidide) ), T. palustris (Potaminidae). The mean abundance of gastropods in Kaliwlingi Village and Sawojajar Village were 20.28 and 16.36 Ind / m² respectively. Diversity Index (H ') of gastropods in the mangrove areas of Kaliwlingi Village and Sawojajar Village are in the low to high category, while the uniformity index is categorized as low. There is no type of gastropod that dominates in the Kaliwlingi and Sawojajar mangrove areas, and gastropod distributed as a grouped.  

THE MAINTENANCE OF A STANDARD OF ELECTROMOTIVE FORCE: NOTES ON STANDARD WESTON CELLS

1930 ◽  
Vol 3 (5) ◽  
pp. 473-489
Author(s):  
A. Norman Shaw ◽  
H. E. Reilley
Keyword(s):  
Electromotive Force ◽  
Essential Feature ◽  
Mean Deviation ◽  
Entire Group ◽  
Standard Cells ◽  
Characteristics Analysis ◽  
A Cell ◽  
The Mean ◽  
The Difference

A detailed procedure for the maintenance of a standard of voltage to within one or two parts in a million is described.In so far as these investigations have proceeded, neutral saturated cells have been found to be superior to acid cells as independent standards for a period of many years, though the latter are preferable for purposes of ordinary precision or shorter periods. The recommended code of procedure is briefly as follows: a number of cells should be constructed according to standard specifications with the new requirements of uniformity of container and speed of preparation, and observations made upon them every few days for a period of three months. The differences in electromotive force (at constant temperature) should be determined between each cell in the group and any one of them chosen arbitrarily as reference cell, and certain new selection and rejection rules applied. In accordance with these rules a cell should be rejected: (a) if its deviation from the mean electromotive force of the group has increased or decreased by 10 microvolts or more during the preceding two weeks; or (b) if it differs in electromotive force from the mean of the group by more than 10 +d microvolts where d is the mean deviation of the cells of the group. If d exceeds 20 microvolts the entire group should be considered untrustworthy. The selected cells should be observed for three additional months, the rejection rules again applied and if a specified proportion survive elimination, the initial reference mean of the laboratory may be established.At intervals of several months additional groups of cells, neutral and acid, should be constructed and exchanges made with laboratories possessing cells of known characteristics. Analysis of the resulting observations determines: (a) the constants in the aging* equation for the reference batch, and (b) the difference between the initial reference mean of the laboratory and the estimated value of the international reference mean.Examples of the analysis of cell observations are given, illustrating the establishment of the initial reference mean, the recapture of this value when the aging coefficients are known, and the preliminary determination of the aging equation for a given group of cells. The use of the aging equation is found to be the essential feature in the attainment of increased precision.A summary of data on standard cells is included.

scholarly journals Determination of Inulin in Foods

2000 ◽  
Vol 83 (3) ◽  
pp. 675-678 ◽  
Author(s):  
Breda Simonovska
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Thin Layer ◽  
Degree Of Polymerization ◽  
Test Solution ◽  
Boiling Water Bath ◽  
Before And After ◽  
The Mean ◽  
The Difference

Abstract A method was developed for determining fructan inulin in various foods (yogurts, honey cakes, chocolates). Warm water was applied for extraction of samples, and mono- and dissacharides were determined by a thin-layer chromatographic densitometric method. A portion of the test solution was hydrolyzed 30 min with 1% oxalic acid in a boiling water bath. Fructose was determined in the hydrolysate. The amount of inulin in a sample was calculated as the difference between the amount of fructose in the sample before and after hydrolysis. The fructose from sucrose formed during the hydrolysis was also considered. The mean recovery from yogurt fortified with 4% inulin was 95.5 ± 4.5% (mean ± standard deviation); from honey cakes extract fortified with 10% inulin, 97.3 ± 5.5%; and from chocolate extract fortified with 30% inulin, 98.6 ± 6.6% (6 replicates in all cases). Determination of glucose is not necessary for analyzing fructans with the composition expressed shortened to GFn−1 (G, glucose; F, fructosyl) with the average degree of polymerization 8 ≤ n ≤ 15.

scholarly journals Establishment of a new relationship between posed smile width and lower facial height: A cross-sectional study

2015 ◽  
Vol 09 (03) ◽  
pp. 394-399 ◽  
Author(s):  
Aby Abraham ◽  
Jinu George ◽  
Elbe Peter ◽  
Koshi Philip ◽  
Rajesh Chankramath ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Facial Height ◽  
The Face ◽  
Facial Proportions ◽  
Males And Females ◽  
The Mean ◽  
The Difference

ABSTRACT Objective: The present study is intended to add a new parameter that would be useful in orthodontic clinical evaluation, treatment planning, and determination of vertical dimension (at occlusion). Materials and Methods: Standardized videographic recording of 79 subjects during posed smile was captured. Each video was then cut into 30 photos using the free studio software. The widest commissure-to-commissure posed smile frame (posed smile width [SW]) was selected as one of 10 or more frames showing an identical smile. Lower third of the face is measured from subnasale to soft tissue menton using a digital vernier caliper. Two values were then compared. Ratio between lower facial height and posed SW was calculated. Results: The co-relation between smiling width and lower facial height was found to be statistically significant (P < 0.01). The ratio of lower facial height and smiling width was calculated as 1.0016 with a standard deviation (SD) = 0.04 in males and 1.0301 with an SD = 0.07 in females. The difference between the mean lower facial height in males and females was statistically significant with a t = 10.231 and P = 0.000. The difference between the mean smiling width in males and females was also statistically significant with a t = 5.653 and P = 0.000. Conclusion: In class I subjects with pleasing appearance, normal facial proportions, normal overjet and overbite, and average Frankfort mandibular angle, the lower facial height (subnasale to soft tissue menton) is equal to posed SW.

scholarly journals The Haemoglobin Concentration of Normal English Males and Females

1933 ◽  
Vol 33 (1) ◽  
pp. 36-41 ◽  
Author(s):  
C. E. Jenkins ◽  
C. S. D. Don
Keyword(s):  
Statistical Significance ◽  
Haemoglobin Concentration ◽  
Gas Analysis ◽  
Experimental Accuracy ◽  
Males And Females ◽  
The Mean ◽  
The Difference ◽  
Made In

The determination of the mean normal haemoglobin concentration has re ceived more attention in America than in this country. Recently Price-Jones (1931) has compared the values in London with those found in America. He used the Haldane haemoglobinometer and his results are as accurate as is possible having regard to the method employed. In America his results were 3 percent. above those of the Haldane gas analysis apparatus (1901) by which theclinical instrument is supposed to be calibrated. Twenty comparisons were made in America and showed that the Haldane gas apparatus gave results averaging 2·6 per cent. below those of the Van Slyke apparatus. Price-Jones considers this to have no statistical significance. From the standpoint of experimental accuracy the difference is appreciable, as all methods for the measurement of oxygen combined with Hb are essentially pragmatic.

scholarly journals Prediction Model for Cigarette Yields Derived from Data Obtained under Two Different Machine Smoking Regimes

2015 ◽  
Vol 26 (7) ◽  
Author(s):  
Stéphane Colard
Keyword(s):  
Carbon Monoxide ◽  
Prediction Model ◽  
Smoking Intensity ◽  
Burning Process ◽  
Testing Scheme ◽  
The Mean ◽  
The Difference ◽  
Burning Model ◽  
Ignition Propensity

Summary“Tar”, nicotine and carbon monoxide (TNCO) cigarette yields determined under different smoking regimes, with and without ventilation blocking, are linearly related to the difference Δt between the smouldering time (cigarette combustion with no puffing) and the smoking time (cigarette combustion with puffing). Δt forms then the basis of yield predictions. The smoulder rate determination used in the calculation of Δt can be difficult for low ignition propensity cigarettes which present some tendency for selfextinguishment. This issue was overcome in a novel testing scheme involving the determination of number of puffs and smoking times under two different smoking regimes and inputting this data into a cigarette burning model. This enabled us to characterise the burning process and provided an extensive set of information such as the mean smoulder rate between puffs or the mass of tobacco burnt during puffs regardless of the smoking regime applied.Good correlations were observed between the mass of tobacco burnt during puffs and TNCO or B[a]P yields. Correlations provide a way to link yields from one smoking regime to another and confirm that yields determined from one regime are sufficient to establish the relationships between yields and smoking intensity. It was concluded that smoke yields for arbitrary smoking regimes can potentially be predicted by determining the puff numbers and smoking times from two different smoking regimes and the smoke yields from only one regime. This testing scheme allows a comprehensive characterisation of a cigarette at reduced cost. [Beitr. Tabakforsch. Int. 26 (2015) 320-333]

scholarly journals Gender Determination with Ischiopubic Index and Upper Pelvic Index in Iranian Adult Radiographic Stereotypes

2021 ◽  
Vol 19 (2) ◽  
Author(s):  
Hossein Ahmadi Kahjoogh ◽  
Maryam Vasheghani Farahani ◽  
Babak Shekarchi ◽  
Beheshteh Abouhamzeh ◽  
Mahdi Isazadeh
Keyword(s):  
Adult Population ◽  
Male And Female ◽  
Imaging Center ◽  
Study Population ◽  
The Mean ◽  
Spss Software ◽  
The Difference ◽  
The Individual ◽  
Female Subjects

Background: Different parts of the skeletal system have been studied in different studies to determine gender. The pelvis is one of the most important skeletal components for the determination of gender and identification of humans. Objectives: The current study aimed to determine gender using the ischiopubic index and upper pelvic index in the adult population of Iran. Methods: In this study, 140 individuals (70 male and 70 female subjects) referring to Athari Imaging Center in Tehran, Iran, for various medical reasons entered the study by giving written and oral consent using the convenience sampling method. Measurements were performed on digital anteroposterior pelvic radiographs (with standard conditions and radiographic stencil distance from the light source as 100 cm). The obtained data were analyzed using SPSS software (version 22). Results: The mean ischemic index of the whole population was 108.88 ± 13.75. The difference in the ischiopubic index between male and female subjects was significant (P < 0.05). The mean upper pelvic index of the whole study population was 81.70 ± 10.09; however, the difference in the upper pelvic index between the two groups of male and female subjects was not significant (P < 0.05). Conclusions: The pelvic ischemic index in Iranian women is higher than that reported for men. If the ischiopubic index is higher than 103, with 93% sensitivity and 73% specificity, it would be female. According to the study of graphs, if there is a special identity for diagnosis, there will be the possibility to match the graph before the death of the individual with the graph taken from skeletal remains.

scholarly journals On the flow of viscous fluids through smooth circular pipes

1914 ◽  
Vol 91 (623) ◽  
pp. 46-53 ◽  
Keyword(s):  
Capillary Tube ◽  
Viscous Fluids ◽  
The Other ◽  
Stream Line ◽  
Circular Section ◽  
Circular Pipes ◽  
Line Flow ◽  
The Mean ◽  
The Difference

1.The problem of the flow of a viscous fluid through a tube of circular section is of considerable interest both to physicists and to engineers. Since Stokes showed the connection between the viscosity of the fluid and the empirical formula given by Poiseuille for the rate of slow or stream-line flow of the fluid through a capillary tube, the tube method has been one of the most useful and accurate for the determination of viscosity. On the other hand, the extensive use of pipes for the transmission of gas, compressed air, water and oil, at speeds much above those which obtain in a Poiseuille experiment, rendered it necessary to investigate the laws of "turbulent" flow of viscous fluids through tubes, and there are at the present time several formulae in use by engineers giving the mean rate of flow of such a fluid through a pipe and the difference of pressure between its ends.

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