SOIL MORPHOLOGY AND SOIL PHYSICAL PROPERTIES. I. SOIL AERATION

1972 ◽  
Vol 52 (3) ◽  
pp. 311-321 ◽  
Author(s):  
K. W. AYRES ◽  
R. G. BUTTON ◽  
E. DE JONG
Keyword(s):  
Soil Structure ◽  
Regression Coefficient ◽  
The Other ◽  
Soil Morphology ◽  
Soil Horizons ◽  
Undisturbed Soil ◽  
Soil Aeration ◽  
Structural Types ◽  
Highly Correlated ◽  
Undisturbed Soil Cores

The relation between soil structure and soil aeration was investigated on undisturbed soil cores from soil horizons exhibiting six distinct kinds of soil structure (prismatic, columnar, blocky, granular, platy, massive) over a broad range of soil texture. Soil aeration was characterized at ⅓ atm suction by measurements of air porosity, relative diffusivity (D/Do) and the rate of oxygen diffusion to a platinum microelectrode (ODR). Aeration was adequate in most of the Chernozemic soil horizons studied; however, aeration in many of the Bnt horizons of the Solonetzic soils was inadequate. Air porosity and D/Do were highly correlated. The regression coefficient for D/Do vs. air porosity for blocky structures was significantly different from that found for the other five structural types. For granular structures a negative correlation was found for ODR vs. air porosity compared with a low positive correlation found for the other structure types.

SOIL MORPHOLOGY AND SOIL PHYSICAL PROPERTIES. II. MECHANICAL IMPEDANCE AND MOISTURE RETENTION AND MOVEMENT

1973 ◽  
Vol 53 (1) ◽  
pp. 9-19 ◽  
Author(s):  
K. W. AYRES ◽  
R. G. BUTTON ◽  
E. DE JONG
Keyword(s):  
Hydraulic Conductivity ◽  
Bulk Density ◽  
Soil Structure ◽  
Pore Space ◽  
Mechanical Impedance ◽  
The Other ◽  
Regression Equations ◽  
Soil Morphology ◽  
Moisture Retention ◽  
Undisturbed Soil

The relations among soil structure, soil mechanical impedance, and moisture retention and movement were investigated on undisturbed soil cores from soil horizons exhibiting six distinct kinds of soil structure (prismatic, columnar, blocky, granular, platy, massive) over a broad range of soil texture. Mechanical impedance was characterized by measurements of bulk density and soil strength. Moisture retention and movement were characterized by measurements of [Formula: see text]-atm moisture content and saturated hydraulic conductivity. The columnar structures from Solonetzic soils were singled out as having a higher mechanical impedance and lower hydraulic conductivity than the other structures, most of which were sampled from Chernozemic soils. Total porosity (P) and bulk density (Db) were highly correlated; however, the regression coefficient for P vs. Db for columnar structures was significantly higher than that found for the other five structural types. Regression equations predicted that the hydraulic conductivity of platy structures could be zero for samples having as much as 15% air-filled pore space at [Formula: see text]-atm suction as compared with 6–8% for the other structures.

Effects of compaction on aeration and morphology of boreal forest soils in Alberta, Canada

2009 ◽  
Vol 89 (1) ◽  
pp. 45-56 ◽  
Author(s):  
A D Startsev ◽  
D H McNabb
Keyword(s):  
Boreal Forest ◽  
Forest Soils ◽  
Soil Compaction ◽  
Boreal Forests ◽  
Warm Season ◽  
Soil Morphology ◽  
Undisturbed Soil ◽  
Protective Measures ◽  
Soil Aeration ◽  
Poor Soil

Poor soil aeration is a factor limiting the productivity of boreal forests in western Canada. Soil compaction reduces air-filled porosity, which is hypothesized to further restrict soil aeration. Soil morphology at nine clearcut sites in west-central Alberta that had been significantly compacted by ground-based harvesting equipment and soil in an adjacent non-trafficked control were related to air-filled porosity and redox regimes. A warm-season air-filled porosity of about 0.1 m3 m-3 separated soils having adequate or restricted aeration, and was confirmed by redox < 200 mV. The values applied to both the undisturbed and compacted soil. Ratios of Feo:Fed and acid-soluble Fe:Mn in concretions were only associated with hydromorphism of undisturbed soil. Compaction reduced soil aeration for 3–4 yr after harvesting, and changed morphology of moderately well-drained soil to imperfectly drained soil at two of four sites; faster removal of water because of slope or vegetation probably prevented changes at the other two sites. Morphology of better and poorer drained soils was not altered by compaction because they either remain adequately aerated or aeration was naturally restricted. Sites with moderately well-drained soils are most at risk of detrimental soil compaction and in need of protective measures to maintain their productivity in these forests. Key words: Soil morphology, drainage class, air-filled porosity, soil aeration, redox potential, boreal forest soils, compaction

Development of Mechanical Soil Stability In An Initial Homogeneous Loam And Sand Under In-Situ Field Conditions

2021 ◽  
Author(s):  
Ulla Rosskopf ◽  
Daniel UTEAU ◽  
Stephan PETH
Keyword(s):  
Soil Structure ◽  
Mechanical Energy ◽  
Soil Stability ◽  
Compression Tests ◽  
Undisturbed Soil ◽  
Initial Development ◽  
Short Period ◽  
Influence Of Substrate ◽  
Undisturbed Soil Cores

Abstract PurposeSoil structure evolving from physical and biological processes is closely related to soil mechanical characteristics and texture. A soil plot experiment in Bad Lauchstädt, Germany, allowed us to study the influence of substrate and genotype on the initial development of mechanical traits, differences between depths, and changes over the course of two years. MethodsPlots were homogeneously filled with a loam and a sand and planted with two maize (Zea mays L.) genotypes (wild type (WT) and rth3 mutant) with contrasting root hair attributes. Undisturbed soil cores were taken in 2019 and 2020 at 14 and 34 cm depth. Confined uniaxial compression tests were performed to determine pre-compression stress (σpc), compressibility (Cc, Cs) and elasticity index (EI). Mechanical energy was calculated based on penetration resistance tests with a penetrometer needle resembling root geometries. Resultsσpc, Cc and Cs were significantly higher in loam as compared to sand, whereas the factor genotype proved to be negligible. Over time, σpc increased and Cc decreased in loam from 2019 to 2020 and Cs declined in both substrates. Higher mechanical energies were observed in loam and partially in WT. Required energy was higher at 14 cm than at 34 cm depth and decreased from 2019 to 2020 in sand. Airdry sand samples required four times as much energy than those at -50 kPa.ConclusionFor the development of the mechanical traits examined texture proved to be the dominating factor and changes in soil stability could be observed within a short period of time.

Isoproturon movement and dissipation in undisturbed soil cores from a grassed buffer strip

Agronomie ◽  
2000 ◽  
Vol 20 (3) ◽  
pp. 297-307 ◽  
Author(s):  
Pierre Benoit ◽  
Enrique Barriuso ◽  
Philippe Vidon ◽  
Benoit Réal
Keyword(s):  
Soil Cores ◽  
Undisturbed Soil ◽  
Buffer Strip ◽  
Undisturbed Soil Cores

scholarly journals An innovative intervention to improve respectful maternity care in three Districts in Ethiopia

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Birkety Mengistu ◽  
Haregeweyni Alemu ◽  
Munir Kassa ◽  
Meseret Zelalem ◽  
Mehiret Abate ◽  
...  
Keyword(s):  
Quality Improvement ◽  
Maternity Care ◽  
Regression Coefficient ◽  
Interrupted Time Series ◽  
The Other ◽  
Respectful Maternity Care ◽  
Experience Of Care ◽  
National Initiative ◽  
Care Training

Abstract Background Mistreatment of women during facility-based childbirth is a major violation of human rights and often deters women from attending skilled birth. In Ethiopia, mistreatment occurs in up to 49.4% of mothers giving birth in health facilities. This study describes the development, implementation and results of interventions to improve respectful maternity care. As part of a national initiative to reduce maternal and perinatal mortality in Ethiopia, we developed respectful maternity care training module with three core components: testimonial videos developed from key themes identified by staff as experiences of mothers, skills-building sessions on communication and onsite coaching. Respectful maternity care training was conducted in February 2017 in three districts within three regions. Methods Facility level solutions applied to enhance the experience of care were documented. Safe Childbirth Checklist data measuring privacy and birth companion offered during labor and childbirth were collected over 27 months from 17 health centers and three hospitals. Interrupted time series and regression analysis were conducted to assess significance of improvement using secondary routinely collected programmatic data. Results Significant improvement in the percentage of births with two elements of respectful maternal care—privacy and birth companionship offered— was noted in one district (with short and long-term regression coefficient of 18 and 27% respectively), while in the other two districts, results were mixed. The short-term regression coefficient in one of the districts was 26% which was not sustained in the long-term while in the other district the long-term coefficient was 77%. Testimonial videos helped providers to see their care from their clients’ perspectives, while quality improvement training and coaching helped them reflect on potential root causes for this type of treatment and develop effective solutions. This includes organizing tour to the birthing ward and allowing cultural celebrations. Conclusion This study demonstrated effective way of improving respectful maternity care. Use of a multipronged approach, where the respectful maternity care intervention was embedded in quality improvement approach helped in enhancing respectful maternity care in a comprehensive manner.

scholarly journals EZ-ALBI Score for Predicting Hepatocellular Carcinoma Prognosis

Liver Cancer ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 734-743
Author(s):  
Kazuya Kariyama ◽  
Kazuhiro Nouso ◽  
Atsushi Hiraoka ◽  
Akiko Wakuta ◽  
Ayano Oonishi ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Liver Function ◽  
Large Scale ◽  
Regression Coefficient ◽  
Information Criterion ◽  
Proportional Hazard ◽  
Cox Proportional Hazard ◽  
Highly Correlated ◽  
Survival Risk ◽  
Good Agreement

<b><i>Introduction:</i></b> The ALBI score is acknowledged as the gold standard for the assessment of liver function in patients with hepatocellular carcinoma (HCC). Unlike the Child-Pugh score, the ALBI score uses only objective parameters, albumin (Alb) and total bilirubin (T.Bil), enabling a better evaluation. However, the complex calculation of the ALBI score limits its applicability. Therefore, we developed a simplified ALBI score, based on data from a large-scale HCC database.We used the data of 5,249 naïve HCC cases registered in eight collaborating hospitals. <b><i>Methods:</i></b> We developed a new score, the EZ (Easy)-ALBI score, based on regression coefficients of Alb and T.Bil for survival risk in a multivariate Cox proportional hazard model. We also developed the EZ-ALBI grade and EZ-ALBI-T grade as alternative options for the ALBI grade and ALBI-T grade and evaluated their stratifying ability. <b><i>Results:</i></b> The equation used to calculate the EZ-ALBI score was simple {[T.Bil (mg/dL)] – [9 × Alb (g/dL)]}; this value highly correlated with the ALBI score (correlation coefficient, 0.981; <i>p</i> &#x3c; 0.0001). The correlation was preserved across different Barcelona clinic liver cancer grade scores (regression coefficient, 0.93–0.98) and across different hospitals (regression coefficient, 0.98–0.99), indicating good generalizability. Although a good agreement was observed between ALBI and EZ-ALBI, discrepancies were observed in patients with poor liver function (T.Bil, ≥3 mg/dL; regression coefficient, 0.877). The stratifying ability of EZ-ALBI grade and EZ-ALBI-T grade were good and their Akaike’s information criterion values (35,897 and 34,812, respectively) were comparable with those of ALBI grade and ALBI-T grade (35,914 and 34,816, respectively). <b><i>Conclusions:</i></b> The EZ-ALBI score, EZ-ALBI grade, and EZ-ALBI-T grade are useful, simple scores, which might replace the conventional ALBI score in the future.

Examining the validity of three methods of measuring pre-readers’ knowledge of storybook events

2021 ◽  
pp. 026565902199554
Author(s):  
Lynn Dempsey
Keyword(s):  
The Other ◽  
Narrative Comprehension ◽  
Important Predictor ◽  
Story Comprehension ◽  
Typically Developing ◽  
Typically Developing Children ◽  
Event Knowledge ◽  
Yield Information ◽  
Highly Correlated ◽  
Planning Intervention

Planning intervention for narrative comprehension deficits requires a thorough understanding of a child’s skill in all component domains. The purpose of this study was to examine the validity of three methods of measuring pre-readers’ event knowledge, an important predictor of story comprehension. Thirty-eight typically developing children (12 males; 26 females) between the ages of 30–59 months ( M = 42.05 SD = 7.62) completed three measures – verbal account, enactment, picture-sequencing – that tapped their knowledge of two different events before listening to stories based on each of those events and completing story comprehension tasks. Scores for verbal account and enactment, but not for picture sequencing, (1) were moderately correlated with comprehension scores for the corresponding story; (2) reflected differential knowledge of the two events, though not in the expected direction; (3) were moderately correlated with one another in the case of each story. In general measures for the same event were more highly correlated with one another than with measures of the other event. Overall, results suggest that verbal account and enactment may yield information useful for clinicians planning intervention for children with narrative comprehension deficits.

A New Test of Auditory-Visual Integration

1973 ◽  
Vol 36 (3_suppl) ◽  
pp. 1063-1066 ◽  
Author(s):  
Andrew H. Gregory ◽  
H. Margaret Gregory
Keyword(s):  
Reading Ability ◽  
The Other ◽  
Nonverbal Intelligence ◽  
Visual Integration ◽  
Morse Form ◽  
Highly Correlated

Two auditory-visual integration tests were given to 86 children from 6 yr. to 11 yr. One test was basically that developed by Birch; the other used Morse-type stimuli. The children were also given tests of nonverbal intelligence, reading and vocabulary. With age and intelligence partialled out, the Morse form of test was significantly more highly correlated with reading ability than the Birch test. Reasons are suggested as to why the Morse version may be a better test of some of the underlying skills involved in reading.

The Semantic Differential as an Index of Traffic Sign Perception and Comprehension

1977 ◽  
Vol 19 (2) ◽  
pp. 183-189 ◽  
Author(s):  
Robert E. Dewar ◽  
Jerry G. Ells
Keyword(s):  
Semantic Differential ◽  
The Other ◽  
Traffic Sign ◽  
Two Factors ◽  
Valid Instrument ◽  
Paper And Pencil ◽  
Verbal Messages ◽  
Highly Correlated

There is a need to develop and validate simple, inexpensive techniques for the evaluation of traffic sign messages. This paper examines the semantic differential (a paper-and-pencil test which measures psychological meaning) as a potential instrument for such evaluation. Two experiments are described, one relating semantic differential scores to comprehension and the other relating this index to glance legibility. The data indicate that semantic differential scores on all four factors (evaluative, activity, potency, and understandability) were highly correlated with comprehension of symbolic messages. These scores were unrelated to glance legibility of verbal messages, but two factors (evaluative and understandability) did correlate with glance legibility of symbolic messages. It was concluded that the semantic differential is a valid instrument for evaluating comprehension of symbolic sign messages and that it has advantages over other techniques.

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