Surgical approaches for the lateral mesencephalic sulcus

2020 ◽  
Vol 132 (5) ◽  
pp. 1653-1658
Author(s):  
Daniel Dutra Cavalcanti ◽  
Bárbara Albuquerque Morais ◽  
Eberval Gadelha Figueiredo ◽  
Robert F. Spetzler ◽  
Mark C. Preul
Keyword(s):  
Statistical Analysis ◽  
The Other ◽  
Surgical Approaches ◽  
Microsurgical Technique ◽  
Horizontal Angle ◽  
Surgical Exposure ◽  
Entry Points ◽  
Anatomical Knowledge ◽  
Neuronavigation System ◽  
The Mean

OBJECTIVEThe brainstem is a compact, delicate structure. The surgeon must have good anatomical knowledge of the safe entry points to safely resect intrinsic lesions. Lesions located at the lateral midbrain surface are better approached through the lateral mesencephalic sulcus (LMS). The goal of this study was to compare the surgical exposure to the LMS provided by the subtemporal (ST) approach and the paramedian and extreme-lateral variants of the supracerebellar infratentorial (SCIT) approach.METHODSThese 3 approaches were used in 10 cadaveric heads. The authors performed measurements of predetermined points by using a neuronavigation system. Areas of microsurgical exposure and angles of the approaches were determined. Statistical analysis was performed to identify significant differences in the respective exposures.RESULTSThe surgical exposure was similar for the different approaches—369.8 ± 70.1 mm2 for the ST; 341.2 ± 71.2 mm2 for the SCIT paramedian variant; and 312.0 ± 79.3 mm2 for the SCIT extreme-lateral variant (p = 0.13). However, the vertical angular exposure was 16.3° ± 3.6° for the ST, 19.4° ± 3.4° for the SCIT paramedian variant, and 25.1° ± 3.3° for the SCIT extreme-lateral variant craniotomy (p < 0.001). The horizontal angular exposure was 45.2° ± 6.3° for the ST, 35.6° ± 2.9° for the SCIT paramedian variant, and 45.5° ± 6.6° for the SCIT extreme-lateral variant opening, presenting no difference between the ST and extreme-lateral variant (p = 0.92), but both were superior to the paramedian variant (p < 0.001). Data are expressed as the mean ± SD.CONCLUSIONSThe extreme-lateral SCIT approach had the smaller area of surgical exposure; however, these differences were not statistically significant. The extreme-lateral SCIT approach presented a wider vertical and horizontal angle to the LMS compared to the other craniotomies. Also, it provides a 90° trajectory to the sulcus that facilitates the intraoperative microsurgical technique.

scholarly journals Bonferroni's and Sidak's modified tests

2006 ◽  
Vol 63 (1) ◽  
pp. 70-76 ◽  
Author(s):  
Armando Conagin ◽  
Décio Barbin
Keyword(s):  
Experimental Data ◽  
Statistical Analysis ◽  
Null Hypothesis ◽  
Practical Importance ◽  
The Other ◽  
Type I ◽  
Test Type ◽  
The Mean ◽  
Mean Differences

Results of practical importance had been discarded testing formulated hypothesis with the aid of statistical analysis of experimental data because of the power of the utilized test. This study compares the power of two Bonferroni's Modified and one Sidak's Modified tests with known tests analyzing 1200 simulated experiments. All differences of means were obtained in relation to the mean of the adopted control to guarantee parametrical magnitude of mean differences. Student's test (type I comparisonwise error) and Waller-Duncan's (Bayesian error) showed the highest percentage of significative differences, followed by Duncan's, BM2, SiM, BM1, DunnettU's, SiN, BN, Dunnettu's, SNK's, REGWF's, REGWQ's, Tukey's, Sidak's and Bonferroni's tests. For differences equal to zero, Student's and Waller-Duncan's test exhibit 5% frequency of rejection of the null hypothesis, in accordance the nominal error I adopted (alpha = 0.05). All other tests had values below 0.05, generally ranging on 0.01 to 0.02 or less. Depending of the number of zero differences and considering the type I experimentwise error I, Student's, Waller-Duncan's and Duncan's tests showed crescent values of errors (> 0.05), proportional to the number of null differences included in the experiment; all other tests exhibit showed of type I experimentwise error < 0.05, most nearing 0.01-0.02 or less. Efficiency of the three "Modified Tests" was close to DunnettU's test, but higher than the other testes of type I experimentwise error nature (MEER).

Synchronous microsurgical anastomosis in complex replantation surgery

2018 ◽  
Vol 43 (10) ◽  
pp. 1044-1049 ◽  
Author(s):  
Szu-Han Wang ◽  
Chung-Chen Hsu ◽  
Chieh-Han John Tzou ◽  
Ching-Hsuan Hu
Keyword(s):  
Case Control Study ◽  
Operation Time ◽  
Case Control ◽  
The Other ◽  
Retrospective Case ◽  
Level Of Evidence ◽  
Microsurgical Technique ◽  
Total Operation Time ◽  
The Mean ◽  
Control Study

We conducted a retrospective case control study of digital replantations in 16 patients from September 2015 to January 2017. Half of the patients were treated by a synchronous microsurgical technique and the other half underwent conventional micro-anastomoses. The total time for anastomoses, total operation time and survival of digits were the major endpoints in this study. The number of digits replanted and the anastomosis method had significant effects on total anastomosis time. The mean anastomosis time for each digit was 46 min and 70 min in the synchronous and conventional groups, respectively, a 34% reduction in anastomosis time in the synchronous group when compared with the conventional group. Patency rates were 87% (13/15) of all the digits replanted in each group. Level of evidence: IV

scholarly journals Displacement field of the Italian area from permanent GPS stations

1998 ◽  
Vol 41 (2) ◽  
Author(s):  
F. Riguzzi ◽  
A. Zanutta
Keyword(s):  
Statistical Analysis ◽  
Central Europe ◽  
Displacement Field ◽  
Time Span ◽  
The Other ◽  
Deformation Analysis ◽  
Gps Data ◽  
Rigorous Statistical Analysis ◽  
The Mean ◽  
Gps Data Processing

A network of nine permanent GPS stations, six of them located in Italy (Cagliari, Matera, Medicina, Noto, Padova and Torino), the other three in Central Europe (Graz, Zimmervald and Wettzell) was been analyzed four times from October 1996 till 1998. After the GPS data processing, a rigorous statistical analysis based on the F (Fisher) test applied on the detected coordinate differences showed significant displacement at Matera, Medicina and Noto. The mean velocities computed for these sites with respect to Wettzell are (0.6 ± 0.3) cm/yr for Matera, (0.7 ± 2) cm/yr for Medicina and (0.6 ± 0.3) cm/yr for Noto.GPS velocities agree with those derived by VLBI and ITRF96 solutions, provided error ellipses are taken into account. The deformation analysis of the last time span shows a suspicious horizontal jump at Padova of (1.0 ± 0.1) cm corresponding to an antenna changing within the same period. This fact shows, in spite of the care used in permanent GPS installation, how the results of the deformation analysis may be strongly conditioned by site problems.

scholarly journals Susceptibility of Certain Cucumber Hybrids (Cucumis Sativus L.) Through Different Planting Dates for Main Pest Infestation Under Field Conditions

2019 ◽  
Vol 16 (04) ◽  
pp. 811-815
Author(s):  
Emam S. E. Abdallah ◽  
Samia A. G. Metwally ◽  
Wafai Z. A. Mikhail
Keyword(s):  
Statistical Analysis ◽  
Cucumis Sativus ◽  
Plant Protection ◽  
The Other ◽  
Seasonal Abundance ◽  
Planting Dates ◽  
Cucumis Sativus L ◽  
Significant Differentiation ◽  
Pest Infestation ◽  
The Mean

ABSTRACT: The present study was carried out in experimental farm of the Plant Protection Research Institute, Qaha, Qalyubiya Governorate during Nile seasons. The study was carried out to evaluate the susceptibility of three cucumber hybrids, Hayel, Ashrak and Bahi, to infestation rate of main destructive pests during two successive seasons 2015 and 2016, whitefly, Bemisia tabaci (Genn.) and Tetranychus urticae. The statistical analysis of the mean number showed significant differences during the two seasons. During the second season hybrids showed significant differentiation. The hybrids (Bahi and Hayel) recorded highest mean number of B. tabaci, followed by hybrid Ashrak with lowest mean number of B. tabaci. The seasonal abundance of the movable stage T. urticae was higher during 2016 than 2015. The statistical analysis of the mean number of movable stage of T. urticae showed significant differentiation for the two successive seasons. On the other hand, population fluctuation of movable stage of T. urticae for the three tested hybrids showed significant differences in the both seasons during three sowing plantation dates indicated significant too.

Effects of aspartic acid salts (Mg and K) on swimming performance of rats and dogs

1964 ◽  
Vol 19 (2) ◽  
pp. 262-264 ◽  
Author(s):  
Le Roy O. Matoush ◽  
C. Frank Consolazio ◽  
Richard A. Nelson ◽  
Gerhard J. Isaac ◽  
Juan B. Torres
Keyword(s):  
Statistical Analysis ◽  
Experimental Design ◽  
Aspartic Acid ◽  
Swimming Performance ◽  
The Other ◽  
Time To Exhaustion ◽  
Treatment Control ◽  
Swimming Time ◽  
The Mean

Five separate experiments were performed to evaluate the effects, if any, of Mg and K salts of aspartic acid on the swimming times of rats and dogs. Experiments 1 and 2 were with rats doing a single swim-to-exhaustion in water maintained at 17 C and 25 C. In experiment 3 dogs performed a single swim-to-exhaustion in 17 C water. During the first three experiments each animal underwent two treatments; a no-treatment control, and an aspartate therapy. Experiment 4 was a long-term single swim-to-exhaustion test. The rats were divided into two groups: one group receiving a placebo and the other group receiving aspartate. Each group swam to exhaustion in 25 C water twice a week for 6 weeks. Experiment 5 was of the same experimental design as experiment 4 with the exception that a double swim-to-exhaustion was used to measure performance. Statistical analysis of the mean swimming times for both rats and dogs in the five experiments showed that average swimming times under control and aspartate therapy were not significantly different. exercise; ergogenic drugs; swimming time to exhaustion endurance criterion Submitted on May 8, 1963

Multi-Center Study of Thromboplastin Calibration Precision – Influence of Reagent Species, Composition, and International Sensitivity Index (ISI)

1993 ◽  
Vol 69 (01) ◽  
pp. 035-040 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Oral Anticoagulants ◽  
International Normalized Ratio ◽  
The Other ◽  
World Health ◽  
Rabbit Brain ◽  
Sensitivity Index ◽  
Bovine Plasma ◽  
Significant Difference ◽  
The Mean ◽  
International Sensitivity Index

SummaryFour thromboplastin reagents were tested by 18 laboratories in Europe, North-America, and Australasia, according to a detailed protocol. One thromboplastin was the International Reference Preparation for ox brain thromboplastin combined with adsorbed bovine plasma (coded OBT/79), and the second was a certified reference material for rabbit brain thromboplastin, plain (coded CRM 149R). The other two thromboplastin reagents were another rabbit plain brain thromboplastin (RP) with a lower ISI than CRM 149R and a rabbit brain thromboplastin combined with adsorbed bovine plasma (RC). Calibration of the latter two reagents was performed according to methods recommended by the World Health Organization (W. H. O.).The purpose of this study was to answer the following questions: 1) Is the calibration of the RC reagent more precise against the bovine/combined (OBT/79) than against the rabbit/plain reagent (CRM 149R)? 2) Is the precision of calibration influenced by the magnitude of the International Sensitivity Index (ISI)?The lowest inter-laboratory variation of ISI was observed in the calibration of the rabbit/plain reagent (RP) against the other rabbit/plain reagent (CRM 149R) (CV 1.6%). The highest interlaboratory variation was obtained in the calibration of rabbit/plain (RP) against bovine/combined (OBT/79) (CV 5.1%). In the calibration of the rabbit/combined (RC) reagent, there was no difference in precision between OBT/79 (CV 4.3%) and CRM 149R (CV 4.2%). Furthermore, there was no significant difference in the precision of the ISI of RC obtained with CRM 149R (ISI = 1.343) and the rabbit/plain (RP) reagent with ISI = 1.14. In conclusion, the calibration of RC could be performed with similar precision with either OBT/79 or CRM 149R, or RP.The mean ISI values calculated with OBT/79 and CRM 149R were practically identical, indicating that there is no bias in the ISI of these reference preparations and that these reference preparations have been stable since their original calibration studies in 1979 and 1987, respectively.International Normalized Ratio (INR) equivalents were calculated for a lyophilized control plasma derived from patients treated with oral anticoagulants. There were small but significant differences in the mean INR equivalents between the bovine and rabbit thromboplastins. There were no differences in the interlaboratory variation of the INR equivalents, when the four thromboplastins were compared.

Prothrombin Time Standardization: Report of the Expert Panel on Oral Anticoagulant Control

1979 ◽  
Vol 42 (04) ◽  
pp. 1073-1114 ◽  
Keyword(s):  
Prothrombin Time ◽  
Expert Panel ◽  
The Other ◽  
Rabbit Brain ◽  
Calibration Constant ◽  
Freeze Dried ◽  
The Mean ◽  
Point Of Intersection ◽  
And Control ◽  
Standardization Report

SummaryIn collaborative experiments in 199 laboratories, nine commercial thromboplastins, four thromboplastins held by the National Institute for Biological Standards and Control (NIBS & C), London and the British Comparative Thromboplastin were tested on fresh normal and coumarin plasmas, and on three series of freeze-dried plasmas. One of these was made from coumarin plasmas and the other two were prepared from normal plasmas; in each series, one plasma was normal and the other two represented different degrees of coumarin defect.Each thromboplastin was calibrated against NIBS&C rabbit brain 70/178, from the slope of the line joining the origin to the point of intersection of the mean ratios of coumarin/normal prothrombin times when the ratios obtained with the two thromboplastins on the same fresh plasmas were plotted against each other. From previous evidence, the slopes were calculated which would have been obtained against the NIBS&C “research standard” thromboplastin 67/40, and termed the “calibration constant” of each thromboplastin. Values obtained from the freeze-dried coumarin plasmas gave generally similar results to those from fresh plasmas for all thromboplastins, whereas values from the artificial plasmas agreed with those from fresh plasmas only when similar thromboplastins were being compared.Taking into account the slopes of the calibration lines and the variation between laboratories, precision in obtaining a patient’s prothrombin time was similar for all thromboplastins.

Platelet Suruival and Function in Rats with Enhanced Thrombotic Tendency

1985 ◽  
Vol 54 (04) ◽  
pp. 739-743 ◽  
Author(s):  
Federica Delaini ◽  
Elisabetta Dejana ◽  
Ine Reyers ◽  
Elisa Vicenzi ◽  
Germana De Bellis Vitti ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Nephrotic Syndrome ◽  
Platelet Function ◽  
Laboratory Tests ◽  
Thrombus Formation ◽  
The Other ◽  
Mean Survival Time ◽  
The Mean ◽  
And Function ◽  
Thrombotic Tendency

SummaryWe have investigated the relevance of some laboratory tests of platelet function in predicting conditions of thrombotic tendency. For this purpose, we studied platelet survival, platelet aggregation in response to different stimuli, TxB2 and 6-keto-PGFlα production in serum of rats bearing a nephrotic syndrome induced by adriamycin. These animals show a heavy predisposition to the development of both arterial and venous thrombosis. The mean survival time was normal in nephrotic rats in comparison to controls. As to aggregation tests, a lower aggregating response was found in ADR-treated rats using ADP or collagen as stimulating agents. With arachidonic acid (AA) we observed similar aggregating responses at lower A A concentrations, whereas at higher AA concentrations a significantly lower response was found in nephrotic rats, despite their higher TxB2 production. Also TxB2 and 6-keto-PGFlα levels in serum of nephrotic rats were significantly higher than in controls. No consistent differences were found in PGI2-activity generated by vessels of control or nephrotic rats.These data show that platelet function may appear normal or even impaired in rats with a markedly increased thrombotic tendency. On the other hand, the significance of high TxB2 levels in connection with mechanisms leading to thrombus formation remains a controversial issue.

Voronoi Analysis of a Soccer Game

2004 ◽  
Vol 9 (3) ◽  
pp. 233-240 ◽  
Author(s):  
S. Kim
Keyword(s):  
Collective Behavior ◽  
Quantitative Assessment ◽  
The Other ◽  
Analysis Method ◽  
Random System ◽  
Soccer Game ◽  
Voronoi Polygons ◽  
The Mean

This paper describes a Voronoi analysis method to analyze a soccer game. It is important for us to know the quantitative assessment of contribution done by a player or a team in the game as an individual or collective behavior. The mean numbers of vertices are reported to be 5–6, which is a little less than those of a perfect random system. Voronoi polygons areas can be used in evaluating the dominance of a team over the other. By introducing an excess Voronoi area, we can draw some fruitful results to appraise a player or a team rather quantitatively.

Solid, slightly soluble phosphorus compounds as nutrient source in activated sludge treatment of forest industry wastewaters

1997 ◽  
Vol 35 (2-3) ◽  
pp. 131-138 ◽  
Author(s):  
Pirjo-Riitta Rantala ◽  
Hannu Wirola
Keyword(s):  
Activated Sludge ◽  
The Other ◽  
Phosphorus Compounds ◽  
Forest Industry ◽  
Phosphorus Concentration ◽  
Nutrient Source ◽  
Sludge Treatment ◽  
Grain Sizes ◽  
Soluble Phosphorus ◽  
The Mean

The aim of the study was to determine if solid, slightly soluble compounds can be used as nutrient source in activated sludge treatment plants instead of liquid phosphoric acid. Four different solid materials were tested in lab-scale solubility tests to find compounds which are least soluble. Two materials were chosen for further studies: apatite and raw phosphate. The use of apatite and raw phosphate as nutrient source was studied in lab-scale activated sludge reactors along with a control reactor where phosphorus was added in liquid form. The phosphorus dosage, measured as elementary phosphorus, was the same for all three reactors. The reactors were fed with pre-clarified chemi-thermomechanical pulp mill (CTMP) wastewater. There were no significant differences in the reductions of organic matter between the three reactors. The mean effluent concentration of total phosphorus was 3 mg P/l in the control reactor and less than 1 mg P/1 in the other two reactors. The soluble phosphorus concentration was more than 2 mg P/l in the control reactor and less than 0.5 mg P/l in the other two. Apatite was an even better nutrient source than raw phosphate. Further lab-scale tests were conducted using two different grain sizes of apatite. No significant differences were found between the studied grain sizes (&lt;0.074 mm and 0.074 mm-0.125 mm). Apatite was then used in full-scale at a CTMP-mill two different times. The experiments showed that the mean concentrations of phosphorus can be reduced radically by using apatite as a nutrient source instead of liquid phosphorus. Solid phosphorus compounds are a viable alternative to reduce the phosphorus load from forest industry wastewater treatment plants.

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