Lateral variability of forest floor properties under second-growth Douglas-fir stands and the usefulness of composite sampling techniques

1986 ◽  
Vol 16 (5) ◽  
pp. 1128-1132 ◽  
Author(s):  
R. E. Carter ◽  
L. E. Lowe

Lateral variability of forest floor physical and chemical properties is examined in LF and H horizons under six naturally regenerated, second-growth Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands in coastal southwestern British Columbia. The number of samples required to predict a mean value at two confidence levels (P = 0.01 and 0.05) and two allowable errors (10 and 20%) are given for each variable. Total C, N, P, S, Zn, pH, and lipids were the least variable, requiring 2–13 samples to estimate a plot mean with a 10% allowable error at the 95% confidence level in LF horizons and 3–51 samples per lot in H horizons. Total K, Cu, and Mn were found to have moderately high lateral variability, while total Ca, Mn, Al, and Fe all required large numbers of samples to estimate the plot mean. In the second part of the paper, composite samples weighted by field depth and bulk density are compared with the depth and bulk density–weighted arithmetic mean of subsamples analyzed individually. Values from analysis of composite samples were within one standard deviation of the mean, with the exception of P and Cu in the LF horizons and lipids in both horizons. Composite values and mean values were significantly correlated across the six sites for all variables except lipids in LF horizons and total C and Mn in both horizons. Composite samples are suggested to provide an adequate estimate of the mean value of subsamples analyzed individually for most purposes and, for some variables (i.e., Ca, Fe, Al, and Mn), the only feasible method of obtaining an estimate of the mean.

Author(s):  
E. A. Akpa ◽  
A. I. Akpama ◽  
O. Oyedele

The study highlights the evaluation of saturated hydraulic characteristics and its influence on some physical and chemical properties of soils developed on coastal plain sands of Obufa Esuk Orok in Calabar, Cross River State, Nigeria. Sixteen grids designed in an experimental plot measured 6 m x 6 m were used for field studies and sixteen (16) soil samples were collected in each of the grid using a soil auger for particle size analysis, bulk density, particle density, total porosity and saturated hydraulic conductivity. The samples were analyzed using standard laboratory procedures. The result showed that the soils were predominantly high in sand content with a mean value of 860.6 g kg-1 and low in silt and clay contents with mean values of 56.1 g kg-1 and 83.3 g kg-1 respectively. The soil texture was predominantly loamy sand. The saturated hydraulic conductivity showed rapid with a mean value of 36 cm min-1. Total porosity was high, a mean value of 52.4 %. Bulk density was low, a mean value of 1.21 Mgm-3 while Particle density was moderate, mean value of 2.55 Mgm-3.  The soil pH showed very strongly acid milieu (mean pH in water = 5.1). Organic carbon and Total nitrogen were low with mean values of 1.1 % and 0.09 % respectively. Available phosphorus was high with a mean value of 36.66 mg kg-1. The exchangeable acidity and exchangeable bases were generally low with mean values of 2.54, 0.59, 0.08 and 0.053 cmolc/kg for calcium, magnesium, potassium and sodium and 0.261and 0.416 cmolc/kg for aluminum and hydrogen. The correlation coefficient (r) between the saturated hydraulic conductivity and texture showed that there was a positive relationship between saturated hydraulic conductivity and sand, silt and clay (correlation coefficient of r = 0.0013, 0.062 and 0.119) at p≤0.05 indicating good relationship. There was also a positive linear relationship between the saturated hydraulic conductivity and bulk density, particle density and total porosity (correlation coefficient values of r = 0.224, 0.03 and 0.107) at p≤0.05 respectively. Despite the positive relationship existed in their correlation, cultural practices such as minimum, zero, mulch tillage and other conservational practices should be adopted to help maintain the rapid condition of the saturated hydraulic conductivity to avoid restriction of water movement and other soluble nutrients in the soil.


2004 ◽  
Vol 35 (2) ◽  
pp. 119-137 ◽  
Author(s):  
S.D. Gurney ◽  
D.S.L. Lawrence

Seasonal variations in the stable isotopic composition of snow and meltwater were investigated in a sub-arctic, mountainous, but non-glacial, catchment at Okstindan in northern Norway based on analyses of δ18O and δD. Samples were collected during four field periods (August 1998; April 1999; June 1999 and August 1999) at three sites lying on an altitudinal transect (740–970 m a.s.l.). Snowpack data display an increase in the mean values of δ18O (increasing from a mean value of −13.51 to −11.49‰ between April and August), as well as a decrease in variability through the melt period. Comparison with a regional meteoric water line indicates that the slope of the δ18O–δD line for the snowpacks decreases over the same period, dropping from 7.49 to approximately 6.2.This change points to the role of evaporation in snowpack ablation and is confirmed by the vertical profile of deuterium excess. Snowpack seepage data, although limited, also suggest reduced values of δD, as might be associated with local evaporation during meltwater generation. In general, meltwaters were depleted in δ18O relative to the source snowpack at the peak of the melt (June), but later in the year (August) the difference between the two was not statistically significant. The diurnal pattern of isotopic composition indicates that the most depleted meltwaters coincide with the peak in temperature and, hence, meltwater production.


Author(s):  
Yuko Komuro ◽  
Yuji Ohta

Conventionally, the strength of toe plantar flexion (STPF) is measured in a seated position, in which not only the target toe joints but also the knee and particularly ankle joints, are usually restrained. We have developed an approach for the measurement of STPF which does not involve restraint and considers the interactions of adjacent joints of the lower extremities. This study aimed to evaluate this new approach and comparing with the seated approach. A thin, light-weight, rigid plate was attached to the sole of the foot in order to immobilize the toe area. Participants were 13 healthy young women (mean age: 24 ± 4 years). For measurement of STPF with the new approach, participants were instructed to stand, raise the device-wearing leg slightly, plantar flex the ankle, and push the sensor sheet with the toes to exert STPF. The sensor sheet of the F-scan II system was inserted between the foot sole and the plate. For measurement with the seated approach, participants were instructed to sit and push the sensor with the toes. They were required to maintain the hip, knee, and ankle joints at 90°. The mean values of maximum STPF of the 13 participants obtained with each approach were compared. There was no significant difference in mean value of maximum STPF when the two approaches were compared (new: 59 ± 23 N, seated: 47 ± 33 N). The coefficient of variation of maximum STPF was smaller for data obtained with the new approach (new: 39%, seated: 70%). Our simple approach enables measurement of STPF without the need for the restraints that are required for the conventional seated approach. These results suggest that the new approach is a valid method for measurement of STPF.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1079.1-1079
Author(s):  
I. Yoshii

Background:Boolean remission criteria is one most popular and stringent criteria in treating patient with rheumatoid arthritis (RA), because it may guarantees a stable clinical course after attaining remission.Objectives:Impact of time span from initiation to achieving Boolean remission on maintaining disease activity, daily activities, and quality of life after attaining Boolean remission was investigated from daily clinical practice data.Methods:685 patients with RA since August 2010 under the T2T strategy were treated. They were monitored for their TJC, SJC, PGA, EGA, CRP, and disease activity indices such as CDAI, SDAI, DAS28, and Boolean criteria at every visit. HAQ-DI score, pain score using visual analog scale (PS-VAS), and EQ-5D were also monitored, and the quality of life score (QOLS) calculated from EQ-5D was determined at every visit from the time of diagnosis (baseline).Of 685 patients, 465 patients had achieved Boolean remission >1 times, and were consecutively followed up for >3 years. These patients were enrolled in the study. Time span from the first visit to first Boolean remission was calculated. The relationship between the time span and each of background parameters, and the relationship between the time span and each of the mean values of the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at the first Boolean remission and thereafter was evaluated statistically.Patients were subsequently divided into the G ≤ 6 and G > 6 groups based on the achievement of first Boolean remission within two groups: time span G ≤ 6 months and G > 6 months. The two groups were compared with regard to the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at first visit and at the time of first Boolean remission, and the mean values of these parameters after remission were evaluated statistically. Moreover, changes of these parameters and the mean Boolean remission rate after the first remission, and SDAI remission rate at the first Boolean remission to thereafter were compared between the two groups statistically.Results:Out of 465 patients, females comprised 343 (73.7%), and the mean age was 67.8 years (range, from 21–95 years). The mean disease duration at first visit was 6.1 years (range, from 1 months–45 years). The mean follow up length was 88.1 months (range: 36–122 months; median: 85 months) and mean time span from the first visit to the first Boolean remission was 8.1 months. The mean SDAI score, HAQ score, PS-VAS, and the QOLS at first visit were 13.3, 0.467, 33.2, and 0.834, respectively. Among the study parameters, PS-VAS and QOLS were significantly correlated with the time span. For parameters at the first Boolean remission, HAQ-DI score, PS-VAS, and QOLS demonstrated significant correlation with the time span, whereas SDAI, HAQ-DI score, PS-VAS, SHS, and QOLS after the Boolean remission demonstrated significant correlation with the time span.The comparison between the G ≤ 6 and the G > 6 groups revealed that the disease duration, HAQ score, and PS-VAS at baseline in the G > 6 were significantly higher than that in the G ≤ 6 group, and QOLS in the G ≤ 6 group was significantly higher than that in the G > 6 group at baseline. Similarly, the HAQ score and PS-VAS at the first Boolean remission in the G > 6 group were significantly higher than that in the G ≤ 6 group, whereas QOLS in the G ≤ 6 group demonstrated no significant difference compared with that in the G > 6 group.The mean value of the SDAI score after the first Boolean remission in the G > 6 group was significantly higher than that in the G ≤ 6 group. Similarly, the SDAI score, HAQ score, and PS-VAS after the first Boolean remission in the G > 6 group were also significantly higher than those in the G ≤ 6 group, and the mean value of the QOLS in the G ≤ 6 group were significantly higher than that in the G > 6 group. The Boolean remission rate and SDAI remission rate after the first Boolean remission were significantly higher in the G ≤ 6 group than those in the G > 6 group.Conclusion:Attaining Boolean remission ≤ 6 months for RA has significant benefit for more stable disease control, that leads good maintenance of ADL.Disclosure of Interests:None declared


2021 ◽  
Vol 900 ◽  
pp. 183-187
Author(s):  
Odunlami Olayemi Abosede ◽  
Akeredolu Funso Alaba

The emissions of carbon monoxide, carbon dioxide, and hydrocarbon from four stroke-powered motorcars and two stroke-powered motorcycles and tricycles in Southwest Nigeria were examined using an automotive 4-gas analyer. Results show that tricycles produced more hydrocarbon and carbon monoxide emissions than motorcycles, while motorcycles emitted more of these pollutants than the gasoline fueled motor cars. (The gasoline fueled motorcars produced lowest hydrocarbon and carbon monoxide while the tricycles produced the highest hydrocarbon and carbon monoxide emissions). On the contrary, motor cars had the highest mean value of carbon dioxide followed by the motorcycles, while tricycles had the least. This could be attributed to the presence of the catalytic converters in some of the motor cars oxidizing carbon monoxide to carbon dioxide. The mean values of hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcars are 630ppm, 10200ppm and 59900ppm. This is much higher than the NESREA (National Environmental standards and Regulations Enforcement Agency) standards as well as Euro II and Euro III (European standards) for vehicular emission. The mean values for hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcycles and tricycles are (2150ppm, 21530ppm and 31200ppm) and (2820ppm, 24880ppm and 38710ppm) respectively. These results do not comply with Nigeria and European emission standards for hydrocarbon, and carbon monoxide. Tricycles and motorcycles account for higher concentrations of hydrocarbon and carbon monoxide pollutants from mobile sources, while they emit carbon dioxide minimally.


2017 ◽  
Vol 11 (1) ◽  
pp. 1041-1048 ◽  
Author(s):  
Mehmet Bekir Unal ◽  
Kemal Gokkus ◽  
Evrim Sirin ◽  
Eren Cansü

Objective: The main objective of this study is to evaluate the availability of lateral antebrachial cutaneous nerve (LACN) autograft for acute or delayed repair of segmented digital nerve injuries. Patients and Methods: 13 digital nerve defects of 11 patients; treated with interposition of LACN graft that harvested from ipsilateral extremity were included in the study. Mean follow up period was 35, 7 months. The mean time from injury to grafting is 53, 3 days. The results of the mean 2PDT and SWMT values of injured /uninjured finger at the end of follow up period were evaluated with Paired T test. The correlation between the defect length and the difference of 2PDT, SWMT values between the uninjured and injured finger at the end of follow up period; were evaluated with Pearson - correlation analysis. Results: The mean value of our 2PDT and SWMT results are ~5,923, ~3, 52, respectively in which can be interpreted between the normal and diminished light touch. The defect length and difference percentage of SWMT values is positively and significantly correlated statistically. Mean length of interposed nerve grafts was 18.5 mm. The age of the patient and the mean values of 2PDT and SWMT with the difference % of 2PDT and % of SWMT are not statistically correlated. Conclusion: Based on results regarding sensory regaining at recipient side and negligible sensory deficit at harvesting side, we suggest that lateral antebrachial cutaneous nerve might be a valuable graft option for digital nerve defects.


2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Dana Alina Magdas ◽  
Adriana Dehelean ◽  
Romulus Puscas

H, C, O stable isotope ratios and the content of some heavy elements of 31 Romanian single-strength organic apple juices collected from four Transylvanian areas are discussed in this study. The aim of this study was to measure the2H/1H,18O/16O,13C/12C ratios of these juices and their elemental profile and to establish a database of authentic values to be used for adulteration and authenticity testing. Our results have shown mean values ofδ18O=-4.2‰andδDδ-46.5‰, respectively, for apples from Transylvania and at the same time the mean value ofδ13C=-28.2‰. The content of Cd, Pb, U, Zn, As was below the acceptable limits stipulated in US-EPA standard for drinking water. Cu and Cr limits exceeded for one single juice; Ni content for some apple juices from Maramures, Alba, and Cluj was higher than the acceptable value.


2020 ◽  
Vol 10 (2) ◽  
pp. 82-86
Author(s):  
Mushtaq Hussain Lashari ◽  
Sumbel Sumera ◽  
Umer Farooq ◽  
Zia Ur Rehman ◽  
Nuzhat Sial ◽  
...  

Background: Health problem are culturally associated with smoking in developing countries. Many hazardous chemicals are taken up by direct or passive smoking causing lipid peroxidation resulting in oxidative stress. Objectives: To estimate the occurrence of smoking and its effects on the lipid profile in populations of Hasilpur, Pakistan. Methodology: The current study was conducted from April - August 2014. Out of 247 apparently healthy subjects of both genders (male=220; female=27), 134 were smokers and 113 were non-smokers. In order to analyze lipid profile, blood samples were collected in early morning hours from the selected members who were asked to fast all night. By using Chem-100 chemistry analyzer, cholesterol, triglyceride, HDL, LDL and VLDL were analyzed. Results: The overall prevalence of smokers was 54.25%. The results showed 60.9% prevalence in males and 0% in females. The mean value of serum triglyceride in control, light smokers and heavy smokers was 147.4±11.7mg/dl, 190.8±41.4 and 205.3±29.7mg/dl, respectively. The results of cholesterol in control, light smokers and heavy smokers were 147.38±7.99mg/dl, 136.8 ±12. 8mg/dl and 173.44±8.63mg/dl, respectively. There was a considerable distinction in the mean level of serum triglyceride and cholesterol between the control group, light smokers and heavy smoker groups (P<00.5). The mean value of HDL of control, light smokers and heavy smokers was 30.93±1.30mg/dl, 31.10±2.45 and 34.58±1.55mg/dl, respectively. The mean values of LDL and VLDL of control, light smokers and heavy smokers were 110.46±3.63mg/dl, 106.00±4.52mg/dl, 117.19±3.48mg/dl and 33.54±3.11mg/dl, 49±9.02mg/dl, 41.06±5.34mg/dl, respectively. There was significant difference in the mean level of HDL, LDL and VLDL between the control group, light smokers and heavy smoker groups (P<0.05). Conclusion: This study concluded that smoking is the reasons of variation in the lipid profile. Elevated period of smoking and the number of smoked cigarettes/day reason the alteration in serum lipid levels and is probably related with increased danger for coronary artery disease.


Author(s):  
Mingjian Zhang ◽  
Feng Huang ◽  
Qing Chen ◽  
Le Wang ◽  
Haisheng Wang ◽  
...  

A mathematical model was established to predict the mean value and variance of tobacco strip during drying processing, based that the physical and chemical properties of tobacco strip as agriculture products show probability distributions. The results show that the model can predict the mean value of moisture content at different times, and there is a certain deviation in predicting the variance of moisture content at initial stage of drying process. However, the prediction value of the variance of tobacco strip is much more accurate while the moisture content is between 8% and 10%, which is the interval of quality requirements.Keywords: tobacco strip; drying; mean value;variance model.  


Author(s):  
Jamileh Fatahi ◽  
Maryam Amiri Jahromi ◽  
Fahimeh Hajiabolhassan ◽  
Amirsalar Jafarpisheh ◽  
Nariman Rahbar ◽  
...  

Background and Aim: The quick speech in noise (Q-SIN) test shows the difficulty of spee­ch perception in noise by specifying signal to noise ratio (SNR) loss. Although the Persian version of Q-SIN has been already constructed, the high-frequency emphasis version of this test is not available. The present study aimed to construct six lists with high-frequency emphasis and implement it. Methods: We are going to prepare a high-frequ­ency emphasis version of Q-SIN and then test it on a small sample. First, researchers designed the relevant sentences; then experts examined their content and face validity. According to the criteria for developing the Q-SIN test, six lists with high-frequency emphasis were prepared. The test was examined on 26 (13 male and 13 female), 18−35 years old individuals with nor­mal hearing. To determine the test reliability, it was re-administered three weeks later with the same conditions. Results: Of 76 sentences prepared, 36 sentences received enough credit after determination of their content and face validity. These 36 senten­ces were used to make 6 lists. The mean value of SNR50 in the Persian language was obtained -4 dB. The mean values of SNR loss in 6 lists were -1.65, -1.8, -2.23, -1.61, -2.38 and -2.07. The results showed equivalency of lists 1, 2, 3, 4, and 6. Examination of test-retest reliability indicated that all lists except the list 2were reliable. Conclusion: The lists of 1, 3, 4, and 6 are reli­able and equivalent and can be used in clinical application.


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