Estimation of Submergent Plant Bed Biovolume using Acoustic Range Information

1990 ◽  
Vol 47 (4) ◽  
pp. 805-812 ◽  
Author(s):  
G. L. Thomas ◽  
S. L. Thiesfeld ◽  
S. A. Bonar ◽  
R. N. Crittenden ◽  
G. B. Pauley
Keyword(s):  
Plant Biomass ◽  
Direct Estimate ◽  
Cross Sectional ◽  
Devils Lake ◽  
Coefficients Of Variation ◽  
Change In The Mean ◽  
Acoustic Surveys ◽  
The Mean ◽  
Fish Interactions ◽  
Chart Recording

Acoustic measurements of the distance between the water surface, top of the aquatic plants, and bottom of the water column were made using chart recording echosounders. The vertical cross sectional area (m2), height (m), biovolume (m3), of aquatic plant beds and variances were computed for three surveys of Devils Lake, Oregon, in May, July, and September, 1986 when coefficients of variation for the plant bed biovolume estimates were 0.18, 0.05, and 0.06, respectively (n = 14). Coefficients of variation for plant biomass estimates (g/m2) computed from SCUBA quadrat samples collected concurrently with the acoustic surveys, were 0.98 (n = 48), 0.81 (n = 90), and 1.05 (n = 90), respectively. The higher precision of the biovolume estimates allow for a 5- to 18-fold greater capability to detect a change in the mean. The lower costs of the biovolume estimates allow for a 10- to 33-fold greater precision-for-cost. The plant bed biovolume variable contains ecologically different information than the biomass variable in that it provides a direct estimate of the amount of aquatic habitat in a lake that is influenced by plants; it should prove useful for evaluating plant control practices and possibly for studying plant-fish interactions.

scholarly journals Personality development from 12 to 18 years of age: changes in mean levels and structure of traits

2004 ◽  
Vol 18 (6) ◽  
pp. 445-462 ◽  
Author(s):  
Jüri Allik ◽  
Kaia Laidra ◽  
Anu Realo ◽  
Helle Pullmann
Keyword(s):  
Personality Traits ◽  
Personality Development ◽  
The Self ◽  
Age Changes ◽  
Cross Sectional ◽  
Adult Personality ◽  
12Th Grade ◽  
Self Reports ◽  
Change In The Mean ◽  
The Mean

The Estonian NEO‐FFI was administered to 2650 Estonian adolescents (1420 girls and 1230 boys) aged from 12 to 18 years and attending 6th, 8th, 10th, or 12th grade at secondary schools all over Estonia. Although the mean levels of personality traits of Estonian adolescents were quite similar to the respective scores of Estonian adults, there was a developmental gap in Agreeableness and Conscientiousness. Three of the five personality dispositions demonstrated a modest cross‐sectional change in the mean level of the trait scores: the level of Openness increased and the levels of Agreeableness and Conscientiousness decreased between 12 and 18 years of age. Although the five‐factor structure of personality was already recognizable in the sample of 12‐year‐old children, it demonstrated only an approximate congruence with the adult structure, suggesting that not all children of that age have developed abilities required for observing one's own personality dispositions and for giving reliable self‐reports on the basis of these observations. The self‐reported personality trait structure matures and becomes sufficiently differentiated around age 14–15 and grows to be practically indistinguishable from adult personality by the age of 16. Personality of adolescents becomes more differentiated with age: along with the growth of mental capacities the correlations among the personality traits and intelligence become smaller. Copyright © 2004 John Wiley & Sons, Ltd.

scholarly journals Within- and between-person variations as determinant factors to calculate the number of observations to estimate usual dietary intake of adolescents

2008 ◽  
Vol 11 (4) ◽  
pp. 541-548 ◽  
Author(s):  
Mariana de M. F. Costa ◽  
Lia Takeyama ◽  
Sílvia M. Voci ◽  
Betzabeth Slater ◽  
Marina V. Silva
Keyword(s):  
Dietary Intake ◽  
Cross Sectional Study ◽  
International Studies ◽  
Macronutrient Intake ◽  
Cross Sectional ◽  
Coefficients Of Variation ◽  
Variance Ratios ◽  
The Mean ◽  
One Way Anova ◽  
Usual Diet

This cross-sectional study describes the variation in the dietary intake of energy and macronutrients based on estimated coefficients of within- and between-person variation and intends to calculate the number of days required to evaluate the dietary intake of adolescents in Piracicaba, Brazil. The sample was made up by ninety-two adolescents aged between eleven and sixteen years. Interviews were performed to assess demographic, anthropometric and dietary variables, which were evaluated by the answers obtained through two 24-hour recalls. Descriptive analyses were performed and variances and Coefficients of variation within- and between-person were obtained by results of one-way ANOVA. The mean energy intake observed was 2,326.2 kilocalories; mean macronutrient intake came to 89.0 grams of fatty acids, 305.3 grams of carbohydrates and 82.2 grams of proteins. Coefficients of within-person variation ranged from 36% to 45%, while between-person coefficients varied from 26% to 31%. Variance ratios ranged from 1.35 (carbohydrate) to 2.62 (protein). The lowest number of observations required to correctly evaluate the usual diet calculated (r = 0.90) was six days, for carbohydrates while the highest was eleven, for proteins. Coefficients of variation were similar to those observed in international studies. We conclude that, in this study, two observations were sufficient to obtain reasonable correlations. However, six evaluations are necessary for these adolescents in order to obtain excellent correlations.

Genetic, maternal, and tank determinants of growth in hatchery-reared juvenile Arctic charr (Salvelinus alpinus)

1991 ◽  
Vol 69 (3) ◽  
pp. 655-660 ◽  
Author(s):  
B. G. E. de March
Keyword(s):  
Egg Size ◽  
Salvelinus Alpinus ◽  
Arctic Charr ◽  
Logistic Growth ◽  
Coefficients Of Variation ◽  
The Social ◽  
Change In The Mean ◽  
Factorial Mating ◽  
Unique Distribution ◽  
The Mean

The relative importance of genetic, maternal, and tank effects on the growth of juvenile Arctic charr (Salvelinus alpinus) was examined in an incomplete factorial mating design (4 dams × 4 sires) with stock from the Fraser River, Labrador, Canada. Egg size and hatching success were related only to dams. Mean weights at 30, 75, and 125 days after swim-up, logistic growth curve parameters describing the change in the mean weight, and a measure of condition, all described within families, were significantly related to both dams and sires and were also correlated with each other. The early patterns of significant differences due to dams and sires changed after approximately 125 days. After this time the mean weights in tanks, although still increasing, became negatively correlated with their coefficients of variation (CV), which had changed only slightly with time. The magnitude of the CVs could not be attributed to specific parents. The changed patterns of differences in the means with time suggested that either (i) the social climate within tanks, measured as the CV, affected the growth of all fish even though they were neither crowded nor underfed, or (ii) an individual's ability to grow was dependent not only on its phenotype (initial weight) but also on its genotype, expressed only in data from sibs. These laboratory results may relate to unique distribution and fitness characteristics of natural Arctic charr populations.

Evaluation of Variation in Permeability Measurements when Using the MARK VI Standpipe

1989 ◽  
Vol 46 (3) ◽  
pp. 447-450 ◽  
Author(s):  
Michael K. Young ◽  
Wayne A. Hubert ◽  
Thomas A. Wesche
Keyword(s):  
Sampling Strategy ◽  
Repeated Readings ◽  
Constant Flow ◽  
Flow Conditions ◽  
Coefficients Of Variation ◽  
Repeated Sampling ◽  
Change In The Mean ◽  
The Mean ◽  
A Site

Using the MARK VI standpipe in a substrate-filled flume under constant flow conditions, we found significant differences in permeability readings made by different people at four of five sites. Coefficients of variation at each site ranged from 27 to 79%. Readings usually varied greatly for each person at each site. To detect a 10% change in the mean permeability at single sites (α = 0.05) would require from 34 to 90 samples; for a 30% change, the range was 4 – 10. Repeated sampling at a site did not produce directional changes in permeability estimates, nor did the performance of individuals change during the test. We propose a sampling strategy based on repeated readings taken by one person.

scholarly journals Variation of Traditional Biomarkers of Liver Injury After an Ultramarathon at Altitude

2018 ◽  
Vol 10 (4) ◽  
pp. 361-365 ◽  
Author(s):  
Jill N. Tirabassi ◽  
Lucianne Olewinski ◽  
Morteza Khodaee
Keyword(s):  
Liver Injury ◽  
Cross Sectional Study ◽  
Medical Attention ◽  
Clinical Consequence ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
Serum Aspartate Aminotransferase ◽  
Change In The Mean ◽  
Level 3 ◽  
The Mean

Background: Significant elevations of traditional biomarkers of liver injury can occur as a result of running an ultramarathon. Hypothesis: Traditional serum biomarker levels of liver injury will significantly increase as the result of participating in this 161-km race at altitude. Study Design: Prospective cross-sectional study. Level of Evidence: Level 3. Methods: A total of 64 (before) and 83 (after) volunteer runners participated in a prospective observational field-based study at the Leadville 100 ultramarathon race. Changes in serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), and bilirubin levels were measured. Results: Of 669 athletes who started the race, 352 successfully completed the race within the 30-hour cutoff (53%). Of 36 runners who had pre- and postrace blood samples taken, the mean ALT, AST, and bilirubin levels were increased from 23 ± 10 U/L, 23 ± 5 U/L, and 0.60 ± 0.29 mg/dL to 117 ± 106 U/L, 485 ± 500 U/L, and 1.60 ± 0.61 mg/dL, respectively (all P < 0.001). There was no change in the mean ALP level ( P = 0.11). There were no significant correlations between postrace ALT, AST, ALP, lactate dehydrogenase (LDH), and bilirubin levels and athletes’ age, sex, body mass index, or finishing time. Significant positive linear correlations between AST, ALT, and LDH with CK were seen. Athletes in this study did not seek medical attention after the race based on an electronic survey (92% response rate). Conclusion: Significant elevations of traditional biomarkers of liver injury occurred as a result of running an ultramarathon at altitude. These correlated with CK, a marker of muscle injury. Clinical Relevance: When reviewing laboratory studies of traditional biomarkers of liver injury in athletes after an ultramarathon, significant elevations may be seen from baseline but are likely to be of no clinical consequence.

Relationship of Sense of Coherence to Other Psychosocial Indices

2004 ◽  
Vol 20 (4) ◽  
pp. 227-236 ◽  
Author(s):  
Sara Holmberg ◽  
Anders Thelin ◽  
Eva-Lena Stiernström
Keyword(s):  
Social Support ◽  
Psychosocial Factors ◽  
Sense Of Coherence ◽  
Living Conditions ◽  
Strong Negative Correlation ◽  
Cross Sectional ◽  
Positive Correlation ◽  
Work Related ◽  
Job Demand ◽  
The Mean

Summary: The concept of “sense of coherence” (SOC) has been widely recognized since it was first introduced by Antonovsky. The originality and usefulness of the SOC scale and its relation to other psychosocial measures has been the subject of lively debate. The aim of this paper was to test for associations between SOC and work-related psychosocial factors (mainly the Job Demand-Control model), general living conditions, education, and social network factors. Cross-sectional data from a population-based sample of 1782 rural males from nine counties in Sweden were analyzed with a multiple regression technique. The subjects were occupationally active at inclusion and the mean age was 50 years (range 40-60). SOC was assessed with the original 29-item questionnaire. Psychosocial variables and lifestyle factors were assessed using questionnaires and structured interviews. The mean SOC among the subjects was 152.3 (standard deviation, 19.4). A strong negative correlation was found between SOC and job demand, whereas a positive correlation with job control was demonstrated. A positive correlation with general living conditions and with social support was also found. However, there was no correlation to education and occupation. Thus, SOC was shown to be strongly correlated to work-related psychosocial factors and social support, but independent of sociodemographic factors.

Age related volume of cadaver-prostates in Bangladesh

1970 ◽  
Vol 4 (2) ◽  
pp. 74-77
Author(s):  
Rukshana Ahmed ◽  
Shamim Ara
Keyword(s):  
Prostate Gland ◽  
Age Groups ◽  
Clinical Settings ◽  
Cross Sectional ◽  
Medical College ◽  
Age Related ◽  
Group A ◽  
Key Words Prostate ◽  
The Mean ◽  
Group B

Pathological changes in the prostate gland occur commonly with advancing age including inflammation, atrophy, hyperplasia and carcinoma and a change in volume is also evident. Estimation of volume of prostate may be useful in a variety of clinical settings. A cross-sectional descriptive study was designed to see the changes in volume of the prostate with advancing age and done in the Department of Anatomy, Dhaka Medical College, Dhaka from August 2006 to June 2007. The study was performed on 70 post-mortem human prostates collected from the unclaimed dead bodies that were under examination in the Department of Forensic Medicine, Dhaka Medical College, Dhaka. The samples were divided into three age groups; group A (10-20 years), group B (21-40 years) and group C (41-70 years). Volume of the sample was measured by using the ellipsoid formula. The mean ± SD volume of prostate was 7.68 ± 3.64 cm3 in group A, 10.61 ± 3.99 cm3 in group B and 15.40 ± 6.31 cm3 in group C. Mean difference in volume between group A and group C, group B and group C were statistically significant (p<0.001). Statistically significant positive correlation was found between age and volume of prostate (r = + 0.579, p < 0.001). Key Words: Prostate; volume; Bangladeshi. DOI: 10.3329/imcj.v4i2.6501Ibrahim Med. Coll. J. 2010; 4(2): 74-77

Brief Overview and Experience of Visual Evoked Potential of First 67 cases at Referral Neuroscience Hospital in Bangladesh

2020 ◽  
Vol 6 (2) ◽  
pp. 74-77
Author(s):  
Mohammad Enayet Hussain ◽  
Bithi Debnath ◽  
AFM Al Masum Khan ◽  
Md Ferdous Mian ◽  
Md Nahidul Islam ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Optic Neuritis ◽  
Clinical Diagnosis ◽  
Optic Neuropathy ◽  
Cross Sectional Study ◽  
P Value ◽  
Pattern Reversal ◽  
Cross Sectional ◽  
The Mean ◽  
Visual Evoked

Background: The visual evoked potentials (VEP) is a valuable tool to document occult lesions of the central visual channels especially within the optic nerve. Objectives: The purpose of the present study was to observe the findings of first few cases of VEP done in the neurophysiology department of the National Institute of Neurosciences (NINS), Dhaka, Bangladesh. Methodology: This cross-sectional study was conducted in the Department of Neurophysiology at the National Institute of Neurosciences and Hospital, Dhaka, Bangladesh from September 2017 to March 2020. All patients referred to the Neurophysiology Department of NINS for VEP were included. Pattern reversal VEPs were done using standard protocol set by International Federation of Clinical Neurophysiology (IFCN). Results: The mean age of the study population was 30.70 (±12.11) years (6-68 years) with 31 (46.3%) male and 36 (53.7%) female patients. The mean duration of illness was 8.71 (±1.78) months (3 days- 120 months). Most common presenting symptom was blurring of vision (37.3%) and dimness of vision (32.8%). Patterned VEP revealed mixed type (both demyelinating and axonal) of abnormality in most cases [29(43.35)]. The most common clinical diagnosis was multiple sclerosis (29.85%) and optic neuropathy (26.87%). In the clinically suspected cases of multiple sclerosis, optic neuropathy and optic neuritis most of the cases of VEP were abnormal and the p value is 0.04 in optic neuropathy and optic neuritis. Conclusion: The commonest presentation of the patients in this series were blurring of vision and dimness of vision. The most common clinical diagnosis for which VEP was asked for, was optic neuritis and multiple sclerosis. Most abnormalities were of mixed pattern (demyelinating and axonal). Journal of National Institute of Neurosciences Bangladesh, 2020;6(2): 74-77

Sonographic Assessment of Amniotic Fluid Volume using Single Deepest Pocket (SDP) among Igbo Women with Uncomplicated Singleton Pregnancies.

2019 ◽  
Vol 2 (1) ◽  
pp. 1-18
Author(s):  
Chijioke Okeudo ◽  
B.U. Ezem
Keyword(s):  
Amniotic Fluid ◽  
Gestational Age ◽  
Cross Sectional Study ◽  
Fluid Volume ◽  
Singleton Pregnancy ◽  
Cross Sectional ◽  
South Eastern ◽  
Amniotic Fluid Volume ◽  
The Mean ◽  
Singleton Pregnancies

Background: The amniotic fluid is fundamental for proper fetal development and growth. Ultrasound visualization of the amniotic fluid permits both subjective and objective estimates of the amniotic fluid. Objective: The objective of this study was to determine the reference values of normal single deepest pocket (SDP) – upper and lower limits, mean SDP and variation of the SDP with gestational age among Igbo women of South-Eastern Nigeria extraction carrying uncomplicated singleton pregnancy. Methodology: This was a prospective cross sectional study involving 400 women carrying uncomplicated singleton pregnancies and who were sure of the date of the first day of their last menstrual period. The single deepest pocket / maximum vertical pool were determined once at presentation at the hospital.. The study was conducted from January 1st to December 31st 2015. The second author carried out all the scanning. The SDP was obtained. Results: The womens’ mean and median ages were the same at 28 years. The gestational age range of the pregnancies was 14-41 weeks. The mean SDP was 5.8cm, while the 5th and 95th percentiles were 3.3cm and 8.5cm respectively. There was no difference in the mean SDP in both term and preterm. There was irregular but continuous rise of mean SDP to a peak of 6.8cm at gestational age of 39 weeks. In conclusion, the participants had a mean SDP of 5.8cm. There was also a positive correlation between SDP and Gestational age. We therefore recommend a longitudinal study to assess perinatal outcome and abnormal amniotic fluid volume among Igbo women of South-Eastern Nigeria. Key words: Single Deepest Pocket, Uncomplicated Singleton Pregnancy, Igbo Women.

Advantages and limitations of the endoscopic tympanoscopy a prospective study

2020 ◽  
Vol 1 (1) ◽  
pp. 012-017
Author(s):  
Najib Zouhair ◽  
Anass Chaouki ◽  
Amine M’khatri ◽  
Youssef Oukessou ◽  
Sami Rouadi ◽  
...  
Keyword(s):  
Middle Ear ◽  
Operating Time ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Invasive Approach ◽  
Intraoperative Bleeding ◽  
Advantages And Disadvantages ◽  
Early Return ◽  
The Mean ◽  
Endoscopic Tympanoplasty

Tympanoplasty is one of the most performed procedures in ENT. The aggressiveness of its microscopic approach has led otologists to adopt the endoscopic approach as a less invasive alternative. The purpose of this work is to appreciate the advantages and disadvantages of this surgical technique. We conducted a prospective descriptive cross-sectional study on 20 interventions within the ENT department of August the 20th 1953 Hospital of Casablanca from April 2019 to June 2019. The average age of operated patients was 36.3 years. Perforations were unilateral in (71%) of the cases with a predominance of the anterior (29%) and subtotal (36%) locations. The tympanoplasties were performed by 3 different senior otologic surgeons, and were left in (57%). The mean operating time was (59.5 min) and the mean anesthesia duration was 75.1 min. Intraoperative vision allowed us to fully visualize the margins of all perforations (100%) and anatomical structures of the middle ear in almost all interventions. The first procedures carried out were filled with difficulties whose management of intraoperative bleeding was the main one in (42.8%) of the cases. (57%) procedures were described as easy. No complication was detected intraoperatively or immediately postoperatively. Endoscopic tympanoplasty has several advantages, including: Minimally invasive approach to the middle ear; panoramic perioperative vision; Gain of operating time; decrease in the duration of anesthesia; Valuable educational tool; postoperative comfort; Decrease in hospital stay and early return to daily activities; Better aesthetic rendering; cost and transportability. However, we also note a number of disadvantages of endoscopic tympanoplasty, particularly: performing the procedure with one hand; difficulty passing through the EAC; 2D vision that alters the perception of depth; management of intraoperative bleeding; fogging; learning curve.

Sign in / Sign up

Export Citation Format

Share Document