scholarly journals Randomized response surface pathway design with skewed starting point and stochastic dose window

2020 ◽  
Vol 7 (1) ◽  
pp. 18
Author(s):  
Trond Holand ◽  
Øystein Evensen ◽  
Sagita Dewi ◽  
Stig Larsen
Keyword(s):  
Atlantic Salmon ◽  
Response Surface ◽  
Initial Dose ◽  
Salt Water ◽  
Lower Boundary ◽  
Response Variable ◽  
Ct Value ◽  
Starting Point ◽  
Starting Dose ◽  
The Mean

<p class="abstract"><strong>Background:</strong> The aim was to introduce response surface pathway (RSP)-design with skewed starting value and stochastic dose-window to estimate optimal efficacy dose (OED) of BP-C2 after IL-1β stimulation in Atlantic salmon.</p><p class="abstract"><strong>Methods:</strong> 54 healthy smolt of Atlantic salmon between 50 and 100 g before habituated to salt water were included. The study was conducted as a one-dimensional, randomized between-patient three-level RSP designed trial with one interventional- and one response variable and odd outcomes. The interventional variable was intraperitoneal injected BPC2 with skewed starting dose of 0.10 mg/100 g related to the initial dose-window &lt;0.02-0.5 mg/100 g. The response variable was the Ct-value of mRNA IL-1β expression 24 hours after injection.</p><p class="abstract"><strong>Results:</strong> Skewed starting value of 0.10 mg/100 g was chosen in the first design-level with a dose-window of &lt;0.0-0.20]. The three smolt obtained a reduction in Ct-value above 15%, and the dose-window adjusted with the lower boundary equals the previous dose. The five smolt at second design-level received 0.16 mg/100g with a dose-window [0.10-0.22]. Four smolt obtained above 15% and one of 0.5% reduction in cycle threshold (Ct)-value. Six smolt in the third design-level received 0.21 mg/100 g and one 0.16 mg/100 g. The mean Ct-value was reduced from 30.0 in the unstimulated situation to 25.0, 24.8 and 26.4 after BP-C2 stimulation of 0.10, 0.16 and 0.21 mg/100 g, respectively. The OED of BP-C2 related to IL-1β was estimated to 0.14 mg/100 g.</p><p class="abstract"><strong>Conclusions: </strong>Skewed starting value in the initial dose-window made the K-adjustment factor and dose-window stochastic. The RSP-procedure works in accordance to the expectation and estimated OED of BP-C2 sufficiently.</p><strong> </strong>

Levothyroxine replacement in primary congenital hypothyroidism: the higher the initial dose the higher the rate of overtreatment

2016 ◽  
Vol 29 (2) ◽  
Author(s):  
Hale Tuhan ◽  
Ayhan Abaci ◽  
Gizem Cicek ◽  
Ahmet Anik ◽  
Gonul Catli ◽  
...  
Keyword(s):  
Congenital Hypothyroidism ◽  
Initial Dose ◽  
Dose Group ◽  
Thyroid Stimulating Hormone ◽  
Categorical Variables ◽  
Delay In Diagnosis ◽  
Starting Dose ◽  
Levothyroxine Replacement ◽  
Study Population ◽  
The Mean

AbstractCongenital hypothyroidism (CH) is the most frequent endocrine disorder during the neonatal period, and a delay in diagnosis and treatment leads to irreversible complications. A high L-thyroxine (LT4) dose is recommended for treatment, while the optimal starting dose is still a matter of debate. The objective of this study was to determine the effects of various starting doses of LT4 on serum thyroid stimulating hormone (TSH) and thyroxine (fT4) at the end of the first month of treatment.A total of 71 patients (37 males, 52.1%) with CH were included in the study. The patients were designated into three sets of subgroups according to the following categorical variables: (i)The mean age of the study population was 22.3±13.2 days at diagnosis. At diagnosis, the mean fT4 was 0.84±0.32 ng/dL, and TSH was 39.3±30 μIU/mL. The mean initial dose of LT4 was 10.9±2.9 μg/kg/day. Overtreatment rates were significantly higher in the highest dose group (12–17 μg/kg/day) compared with the lowest dose group (6–9.9 μg/kg/day) (61.5% and 25%, respectively, p<0.05). None of the patients was undertreated.In this study, we found that the rate of overtreatment was significantly higher in patients who were given LT4 doses of 12–17 μg/kg/day. Thus, monitoring thyroid functions earlier than one month of treatment is necessary.

Assessment of nutritional status of students of medical institute according to the blood biochemical parameters

2020 ◽  
pp. 55-63
Author(s):  
Rofail Rakhmanov ◽  
Elena Bogomolova ◽  
Mariya Shaposhnikova ◽  
Mariya Sapozhnikova
Keyword(s):  
Nutritional Status ◽  
Lower Boundary ◽  
Density Lipoprotein ◽  
Blood Parameters ◽  
Medical Institute ◽  
Specific Situation ◽  
Mathematical Methods ◽  
Normal Range ◽  
Mean Values ◽  
The Mean

The biochemical blood parameters characterizing the students ’nutritional status were evaluated: protein, lipid, carbohydrate metabolism, a number of minerals. The mean values, errors of the mean, median (Me), boundary (Q) and the range of 25–75 percentiles were determined. In 9.1 % of students and 28.6 % of students, the total protein was increased. Creatinine in men was in the upper normal range, in women — at the upper limit of normal, of which 46.2 % was higher than normal. The interval Q25–75 of uric acid in students is determined in the lower normal zone. In 40.0 % of men, decreased high-density lipoprotein cholesterol (Q25–75 corresponded to 1.15–1.79), in women — below normal, Q25–75 5 was 1.3–1.5, decreased in 73.3 %. Me and Q25–75 iron were in the lower normal range; 14.1 % of men and 13.2 % of women are below normal. Me sodium and potassium at the level of the lower boundary of the norm, Q25–75 in the lower zone of the norm: in 16.0 % and 15.4 % of students the levels are reduced. Calcium is slightly above the lower limit of the norm, Q25–75–2.1–2.24, indicating an insufficient intake in the whole group; 25.0 % are below normal. The border of the 25th percentile of magnesium is at the level of the lower border of the norm, in 19.2 % it is reduced. 7.2 % lack of chlorine. Phosphorus is normal, but Q25–75 is in the upper zone; 17.9 % increased. Biochemical markers can identify individuals with metabolic disorders of nutrients. Statistical indicators — the median, the boundaries of 25–75 quartiles and their scope characterize the metabolism of macronutrients and minerals in the group and subgroups of students. Laboratory and mathematical methods can provide a basis for identifying the specific causes of these changes. For this, you can use the questionnaire method of studying the nutrition of students, possibly using the developed questionnaires for a specific situation.

Descriptive statistics

2017 ◽  
Author(s):  
Andrew Gelman ◽  
Deborah Nolan
Keyword(s):  
Descriptive Statistics ◽  
Metabolic Rates ◽  
World Record ◽  
Linear Combinations ◽  
Record Times ◽  
Starting Point ◽  
Statistics Course ◽  
Scatter Plots ◽  
Economic Indexes ◽  
The Mean

Descriptive statistics is the typical starting point for a statistics course, and it can be tricky to teach because the material is more difficult than it first appears. The activities in this chapter focus more on the topics of data displays and transformations, rather than the mean, median, and standard deviation, which are covered easily in a textbook and on homework assignments. Specific topics include: distributions and handedness scores; extrapolation of time series and world record times for the mile run; linear combinations and economic indexes; scatter plots and exam scores; and logarithmic transformations and metabolic rates.

Is Speed of Onset of Anti-anxiety Efficacy with Pregabalin Influenced by Starting Dose?

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
B. Herman ◽  
F. Mandel
Keyword(s):  
Dose Response ◽  
Change Score ◽  
Early Improvement ◽  
Response Effect ◽  
Starting Dose ◽  
Dsm Iv ◽  
The Mean ◽  
Dose Response Effect ◽  
Titration Schedule ◽  
Speed Of Onset

Objective:There appears to be no dose-response effect for pregabalin at doses of 300-600 mg, and a modest dose-response effect in the range of 150-300 mg. The goal of the current investigation was to determine the effect of the starting dose on the speed of onset of anxiolytic efficacy.Methods:Data were analyzed from 7 trials of outpatients with DSM-IV GAD and a HAM-A total score ≥18. Starting doses of pregabalin ranged from 100 mg (N=301) or 150 mg (N=104), to 200 mg (N=167) and 300 mg (N=388). Assessment of early improvement included the HAM-A total score and CGI-Severity and Improvement scores.Results:The mean Week 1 HAM-A change score was similar for a starting dose of 200 mg/d with no titration (-8.24) when compared to patients who started on 200 mg/d and then titrated up to 400 mg/d on Day 4 (-8.64). The mean Week 1 HAM-A change score was somewhat higher for patients started on 300 mg/d, and then titrated to 450 mg/d on Day 4/5 (-8.84) when compared to patients started on a lower (100/150 mg/d) dose and titrated on Day 5 to 400/450 mg/d (-7.32). Starting on a dose of 300 mg/d with no titration resulted in an intermediate Week 1 change score (-7.87). The interaction of starting dose and titration schedule with baseline anxiety severity will be summarized in detail.Conclusion:The initial dose of pregabalin appears to have only a weak effect on the speed of onset of anxiolytic improvement.

PARAMETER ESTIMATION ON HURDLE POISSON REGRESSION MODEL WITH CENSORED DATA

2012 ◽  
Vol 57 (1) ◽  
Author(s):  
SEYED EHSAN SAFFAR ◽  
ROBIAH ADNAN ◽  
WILLIAM GREENE
Keyword(s):  
Regression Model ◽  
Count Data ◽  
Poisson Regression ◽  
Goodness Of Fit ◽  
Poisson Model ◽  
Likelihood Method ◽  
Poisson Regression Model ◽  
Response Variable ◽  
The Mean ◽  
Over Dispersion

A Poisson model typically is assumed for count data. In many cases, there are many zeros in the dependent variable and because of these many zeros, the mean and the variance values of the dependent variable are not the same as before. In fact, the variance value of the dependent variable will be much more than the mean value of the dependent variable and this is called over–dispersion. Therefore, Poisson model is not suitable anymore for this kind of data because of too many zeros. Thus, it is suggested to use a hurdle Poisson regression model to overcome over–dispersion problem. Furthermore, the response variable in such cases is censored for some values. In this paper, a censored hurdle Poisson regression model is introduced on count data with many zeros. In this model, we consider a response variable and one or more than one explanatory variables. The estimation of regression parameters using the maximum likelihood method is discussed and the goodness–of–fit for the regression model is examined. We study the effects of right censoring on estimated parameters and their standard errors via an example.

Statistical Analyses of High Cycle Fatigue French Data for Austenitic SS

2014 ◽  
Author(s):  
Géraud Blatman ◽  
Thomas Métais ◽  
Jean-Christophe Le Roux ◽  
Simon Cambier
Keyword(s):  
Strain Amplitude ◽  
High Cycle Fatigue ◽  
Experimental Testing ◽  
Austenitic Stainless Steels ◽  
Fatigue Curve ◽  
Statistical Analyses ◽  
Starting Point ◽  
The Mean ◽  
Number Of Cycles ◽  
Selection Of

In the 2009 version of the ASME BPV Code, a set of new design fatigue curves were proposed to cover the various steels of the code. These changes occurred in the wake of publications [1] showing that the mean air curve used to build the former ASME fatigue curve did not always represent accurately laboratory results. The starting point for the methodology to build the design curve is the mean air curve obtained through laboratory testing: coefficients are then applied to the mean air curve in order to bridge the gap between experimental testing and reactor conditions. These coefficients on the number of cycles and on the strain amplitude are equal to 12 and 2 respectively in the 2009 ASME BPV code, using the mean air curve proposal from NUREG/CR-6909 [1]. Internationally, with the same mean air curve, other proposals have emerged and especially in France [2]-[3] where a consensus seems to be reached on the reduction of the coefficient on strain amplitude. This paper provides statistical analyses of the experimental data obtained in France at high-cycle for austenitic stainless steels. It enables to bring arguments for the selection of a coefficient on strain amplitude in the French RCC-M code, where less scatter on the data is witnessed due to fewer material grades.

scholarly journals Modelling Bark Thickness of Norway Spruce (Picea abies Karst)

2019 ◽  
Vol 10 (2) ◽  
pp. 125-135
Author(s):  
Jusuf Musić ◽  
Velid Halilović ◽  
Jelena Knežević ◽  
Admir Avdagić ◽  
Aida Ibrahimspahić ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Bosnia And Herzegovina ◽  
Timber Harvesting ◽  
Bark Thickness ◽  
Optimal Model ◽  
Breast Height ◽  
Starting Point ◽  
Mean Diameter ◽  
The Mean ◽  
Actual Method

Background and Purpose: Bark thickness and its share in the volume of roundwood are the most important characteristics of the bark, particularly in the process of timber harvesting, and during scaling of processed logs. Therefore it is very important to have at disposal relatively accurate data regarding these characteristics of bark for particular tree species. The main goal of this paper is to investigate the thickness of the bark and its share in the volume of roundwood of Norway spruce. Materials and Methods: The research was carried out in the area of the Canton 10 of the Federation of Bosnia and Herzegovina and it encompassed 393 trees of Norway spruce from 10 cm to 115 cm of thickness at breast height. Measuring of the mean diameter and double thickness of bark was conducted by section method. In total, 4,647 diameters and bark thicknesses were measured in different relative lengths of stems or in average 10.6 measurements per one stem. Results: As an optimal model for the evaluation of double thickness of the bark of Norway spruce depending on mean diameter of roundwood the function with designated determination coefficient of 0.7142 was selected. The obtained results have confirmed the previously defined relations of investigate characteristics, which are as following: a) with the increase of mean diameter of roundwood (section) double bark thickness is increased from 9.26 mm (thickness class 12.5 cm) to 31.65 mm (thickness class 92.5 cm); b) with the increase of mean diameter of roundwood the share of bark in its volume decreased from 14.26% (thickness class 12.5 cm) to 6.73% (thickness class 92.5 cm). Conclusions: By the actual method of estimating bark thickness or the share of bark in the volume of roundwood of Norway spruce in the forestry of the Federation of Bosnia and Herzegovina a significant error was created which increases with the increase of mean diameter. The obtained results point to the necessity of investigation of these bark characteristics in Bosnia and Herzegovina and represent an inevitable starting point for making adequate tables of bark thickness and its percentage share in the volume of roundwood of Norway spruce.

scholarly journals Ultrasonic Heating Detects Lipiodol Deposition within Liver Tumors after Transarterial Embolization: An In Vivo Approach

Biology ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 901
Author(s):  
Natsuhiko Saito ◽  
Toshihiro Tanaka ◽  
Kiyoyuki Minamiguchi ◽  
Ryosuke Taiji ◽  
Hideyuki Nishiofuku ◽  
...  
Keyword(s):  
Sound Velocity ◽  
Temperature Coefficient ◽  
Rat Liver ◽  
Liver Tumors ◽  
Transarterial Embolization ◽  
Rate Of Change ◽  
Accumulation Ratio ◽  
Ct Value ◽  
The Mean

Computed tomography (CT) is the standard method to evaluate Lipiodol deposition after transarterial embolization (TAE) for a long period. However, iodine but not Lipiodol can be observed on CT. A minimally invasive other method to detect Lipiodol has been needed to evaluate accurate evaluation after procedure. The purpose of this study was to evaluate the efficacy of using the rate of change in sound velocity caused by ultrasonic heating to reflect Lipiodol accumulation after TAE in a rat liver tumor model. We analyzed the association of this developed technique with CT images and histological findings. Eight rats bearing N1S1 cells were prepared. After confirmation of tumor development in a rat liver, Lipiodol was injected via the hepatic artery. Seven days after TAE, CT scan and sound velocity changes caused by ultrasonic heating were measured, and then the rats were sacrificed. An ultrasonic pulse-echo method was used to measure the sound velocity. The temperature coefficient of the sound velocity in each treated tumor was evaluated and compared with the mean CT value and the histological Lipiodol accumulation ratio. Pearson’s correlation coefficients were calculated to assess the correlation between the measured values. The correlation coefficient (r) of the mean CT value and histological Lipiodol accumulation ratio was 0.835 (p = 0.010), which was considered statistically significant. Also, those of the temperature coefficient of the sound velocity and the histological Lipiodol accumulation ratio were statistically significant (r = 0.804; p = 0.016). To our knowledge, this is the first study that reported the efficacy of ultrasonic heating to detect Lipiodol accumulation in rat liver tumors after TAE. Our results suggest that the rate of change in sound velocity caused by ultrasonic heating can be used to evaluate Lipiodol accumulation in liver tumors after TAE, and thus could represent an alternative to CT in this application. This new innovative technique is easy to treat and less invasive in terms of avoiding radiation compared with CT.

scholarly journals OPTIMIZATION OF REFLUX EXTRACTION FOR CAESALPINIA SAPPAN LINN. WOOD BY USING RESPONSE SURFACE METHODOLOGY

2020 ◽  
Vol 83 (1) ◽  
pp. 85-92
Author(s):  
Mohd Azahar Mohd Ariff ◽  
Muhammad Syafiq Abd Jalil ◽  
Noor ‘Aina Abdul Razak ◽  
Jefri Jaapar
Keyword(s):  
Particle Size ◽  
Response Surface Methodology ◽  
Drinking Water ◽  
Response Surface ◽  
Extraction Time ◽  
Percentage Error ◽  
Optimum Conditions ◽  
Caesalpinia Sappan ◽  
The Mean ◽  
Repeated Runs

Caesalpinia sappan linn. (CSL) is a plant which is also known as Sepang tree contains various medicinal values such as to treat diarrhea, skin rashes, syphilis, jaundice, drinking water for blood purifying, diabetes, and to improve skin complexion. The aim of this study is to obtain the most optimum condition in terms of the ratio of sample to solvent, particle size, and extraction time to get the highest amount of concentration of the CSL extract. In this study, the ranges of each parameters used were: ratio sample to solvent: 1.0:20, 1.5:20, 2.0:20, 2.5:20, 3.0:20, particle size: 1 mm, 500 um, 250 um, 125 um, 63 um, and extraction time: 1 hr, 2 hr, 3 hr, 4 hr, 5 hr. The concentration was analyzed using a UV-vis spectrophotometer. The optimum conditions were obtained by response surface methodology. From the design, 20 samples were run throughout this experiment. The optimized value from the RSM were 2.0:20 for ratio sample to solvent, 125 µm of particle size and 2.48 hours with the concentration of 37.1184 ppm. The accuracy of the predictive model was validated with 2 repeated runs and the mean percentage error was less than 3%. This confirmed the model’s capability for optimizing the conditions for the reflux extraction of CSL’s wood.

Flow Fields Inside Stocked Fish Cages and the Near Environment

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
Lars C. Gansel ◽  
Siri Rackebrandt ◽  
Frode Oppedal ◽  
Thomas A. McClimans
Keyword(s):  
Atlantic Salmon ◽  
Water Flow ◽  
Laboratory Tests ◽  
Numerical Models ◽  
Field Measurements ◽  
Flow Patterns ◽  
Fish Swimming ◽  
Swimming Depth ◽  
Starting Point ◽  
Fish Cages

This study explores the average flow field inside and around stocked Atlantic salmon (Salmo salar L.) fish cages. Laboratory tests and field measurements were conducted to study flow patterns around and through fish cages and the effect of fish on the water flow. Currents were measured around an empty and a stocked fish cage in a fjord to verify the results obtained from laboratory tests without fish and to study the effects of fish swimming in the cage. Fluorescein, a nontoxic, fluorescent dye, was released inside a stocked fish cage for visualization of three-dimensional flow patterns inside the cage. Atlantic salmon tend to form a torus shaped school and swim in a circular path, following the net during the daytime. Current measurements around an empty and a stocked fish cage show a strong influence of fish swimming in this circular pattern: while most of the oncoming water mass passes through the empty cage, significantly more water is pushed around the stocked fish cage. Dye experiments show that surface water inside stocked fish cages converges toward the center, where it sinks and spreads out of the cage at the depth of maximum biomass. In order to achieve a circular motion, fish must accelerate toward the center of the cage. This inward-directed force must be balanced by an outward force that pushes the water out of the cage, resulting in a low pressure area in the center of the rotational motion of the fish. Thus, water is pulled from above and below the fish swimming depth. Laboratory tests with empty cages agree well with field measurements around empty fish cages, and give a good starting point for further laboratory tests including the effect of fish-induced currents inside the cage to document the details of the flow patterns inside and adjacent to stocked fish cages. The results of such experiments can be used as benchmarks for numerical models to simulate the water flow in and around net pens, and model the oxygen supply and the spreading of wastes in the near wake of stocked fish farms.

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