The optimal spacing interval between principal shelterbelts of the farm-shelter forest network

The farm-shelter forest network is a complex grid protection system, with a windbreak that is distinctly different from that of the single shelterbelt. We selected the farm-shelter forest network of a jujube field in the Tarim Basin of northwest China and used a combination of field measurements and wind tunnel tests to determine the optimal spacing interval between principal shelterbelts. The wind speed reductive curve of the farm-shelter forest network showed a gradual wind speed tendency to stability. Therefore, a model was established based on the energy transfer balance between the upper and the lower airflows for a steady wind speed. The prediction error of the model was found to be < 1%. The model results indicated that increasing the spacing interval between principal shelterbelts from 10 to 20 H, where H is the shelterbelt height, maintained more than 70% of the windbreak effect of the farm-shelter forest network. If the spacing interval between principal shelterbelts were to be increased from 10 to 20 H, the jujube planting area would be increased by 0.54%. Therefore, a thorough consideration of the windbreak effect of each shelterbelt, the synergistic effects of shelterbelts, the windbreak effects of tall crops, and the effects of temperature and humidity in farm-shelter forest networks indicates that increasing the spacing interval will not only maintain the windbreak effect, but it will also reduce the side effects of shelterbelts, increase the planting area, favor mechanized operation, and improve planting efficiency.

Optimizing song retention through the spacing effect

The spacing effect refers to the improvement in memory retention for materials learned in a series of sessions, as opposed to massing learning in a single session. It has been extensively studied in the domain of verbal learning using word lists. Less evidence is available for connected discourse or tasks requiring the complex coordination of verbal and other domains. In particular, the effect of spacing on the retention of words and music in song has yet to be determined. In this study, university students were taught an unaccompanied two-verse song based on traditional materials to a criterion of 95% correct memory for sung words. Subsequent training sessions were either massed or spaced by two days or one week and tested at a retention interval of three weeks. Performances were evaluated for number of correct and incorrect syllables, number of correctly and incorrectly pitched notes, degree notes were off-pitch, and number of hesitations while singing. The data revealed strong evidence for a spacing effect for song between the massed and spaced conditions at a retention interval of three weeks, and evidence of no difference between the two spaced conditions. These findings suggest that the ongoing cues offered by surface features in the song are strong enough to enable verbatim recall across spaced conditions, as long as the spacing interval reaches a critical threshold.

A study of knowledge, attitude and practice regarding child birth spacing and its methods among the antenatal women of rural Thoothukudi, Tamil Nadu

Background: India is the second highest populated country in the world with 1.32 billion populations and will reach 1.53 billion by next 30 years. The birth spacing is defined as the time interval between two births. While knowledge of birth spacing has reached substantial levels, conversion of this knowledge into a change in attitude and practicing of birth spacing appears lagged and challenged. Our objective was to assess the knowledge, attitude and practice of various birth spacing methods among the antenatal women of rural Thoothukudi.Methods: A descriptive cross sectional study was conducted among antenatal women who came for their routine antenatal checkup at the PHCs. Data was collected with a pre-tested, semi-structured questionnaire and analysed. Results were expressed in percentages and proportions.Results: Out of 120 antenatal women participated in the study, majority (82.5%) had knowledge about ideal spacing period of 2 to 3 years. But majority of the women (79.20%) did not practice any of the birth spacing methods and only 20.80% women were actually practicing some of the birth spacing methods and the common method was Copper-T. The common reason for not adopting and discontinuance of contraceptive method is fear of its adverse effects (31%).Conclusions: The study results revealed that most of the women were aware that birth spacing between pregnancies is important and knew only about Cu-T. Also they knew that the ideal spacing interval should be 3 years. Thus Health Education Programmes are a must to enhance the knowledge of antenatal women about birth spacing methods.

The Optimal Spacing Interval Between Principal Shelterbelts of the Farm-shelter Forest Network

The farm-shelter forest network is a complex grid protection system, with a windbreak that is distinctly different from that of the single shelterbelt. We selected the farm-shelter forest network of a jujube field in the Tarim Basin of northwest China and used a combination of field measurements and wind tunnel tests to determine the optimal spacing interval between principal shelterbelts. The wind speed reductive curve of the farm-shelter forest network showed a gradual wind speed tendency to stability. Therefore, a model was established based on the energy transfer balance between the upper and the lower airflows for a steady wind speed. The prediction error of the model was found to be < 1%. The model results indicated that increasing the spacing interval between principal shelterbelts from 10 H to 20 H, where H is the shelterbelt height, maintained more than 70% of the windbreak effect of the farm-shelter forest network. If the spacing interval between principal shelterbelts were to be increased from 10 H to 20 H, the jujube planting area would be increased by 0.54%. Therefore, a thorough consideration of the windbreak effect of each shelterbelt, the synergistic effects of shelterbelts, the windbreak effects of tall crops, and the effects of temperature and humidity in farm-shelter forest networks indicates that increasing the spacing interval will not only maintain the windbreak effect, but it will also reduce the side effects of shelterbelts, increase the planting area, favor mechanized operation, and improve planting efficiency.

Dead level contour technical design parameters required for sustainable crop production in semi-arid areas of Zimbabwe

Smallholder farmers in sub-Saharan Africa are increasingly exposed to risks such as erratic rainfall, prolonged dry spells, and frequent droughts that threaten sustainable crop production. This study assessed the effectiveness of dead level contours with innovations (DLC INN), dead level contours with infiltration pits (DLC INFIL), dead level contours with open channels (DLC OPEN) and standard graded contours (SGCs) in harvesting and storing water in the channel, improving crop conditions during the critical stages of maize growth on different soil textural groups in the Zvishavane District of Zimbabwe. The DLC INFIL, DLC OPEN and DLC INN outperformed the SGC under medium- and heavy-textured soils, with yields ranging between 1.7 and 2.36 t/ha compared to 0.9 t/ha for the SGC. For light textured soils, the DLC INN had the highest maize yield, averaging 0.8 t/ha. On heavy textured soils using DLC INN, DLC INFIL and DLC OPEN, smallholder farmers may use a spacing interval of 24–27 m. On medium textured soils, DLC INN and DLC INFIL can be used at a spacing interval of 18–21 m and 12 to 15 m with DLC OPEN. On light textured soils, farmers are advised to invest in DLC INN only, using a spacing interval of 12–15 m.

Determining Appropriate Lane-Changing Spacing for Off-Ramp Areas of Urban Expressways

Congestion has become a significant issue in recent years and has greatly affected the efficiency of urban traffic operation. Random and disorderly lane-changing behavior greatly reduces traffic capacity and safety. This paper is mainly concerned with the relationship of lane-changing spacing intervals provided by off-ramp facilities and traffic flow conditions. Through field investigations in Beijing, several typical lane-changing behaviors at off-ramp areas are analyzed. By using field traffic data and actual road geometry parameters, VISSIM-based micro-behavior simulations at off-ramp areas are implemented to obtain traffic flow conditions with different lane-changing spacing intervals and other model parameters, such as traffic volume and ratio of off-ramp vehicles. Then, the numerical relationships between traffic flow state and model parameters can be shown. The results show that with increasing traffic volume and the ratio of off-ramp vehicles, the lane-changing spacing interval required by vehicles should be increased. For the same ratio of off-ramp vehicles, if the traffic volume increases by 100 pcu/h/lane (pcu is a unit to stand for a standard passenger car), the corresponding lane-changing spacing interval should be increased by a spacing of 50–100 m to avoid increasing congestion. Based on the results of this paper, smart lane management can be implemented by optimizing lane-changing spacing intervals and lane-changing behaviors to improve traffic capacity.

Effect of fertilizer levels and plant spacing on the performance of Mucuna prureins (velvet bean) in the Northern Guinea Savanna of Nigeria

Fertilizer recommendation for crop and plant spacing is dynamic process in view of the generation of new knowledge with management practices. Information such as (phosphorus levels and plant spacing) on maintaining adequate soil fertility is very much important for producing better forages for livestock. Leguminous crop such as Velvet bean (Mucuna pruriens) can alleviate some of these problems. Field experiment was conducted to access the effect of phosphorus fertilizer application level at 0, 80 and 120kg/ha and plant spacing interval of 30, 60 and 90cm of Velvet bean. Application of 80kg/ha of phosphorus fertilizer significantly influenced the performance of Mucuna plant such as plant height, number of branches and forage yield. Plant spacing interval of 30cm resulted in better stand count, taller plant, higher number of branches and forage yield per plant. Famers in Northern Guinea Savanna of Nigeria can adopt the application of phosphorus fertilizer at 80kg/ha and using narrower spacing (25cm by 30cm) for better yield of Mucana, thereby increasing farm output and animal performance.Keywords: phosphorus level, plant spacing, Mucuna pruriens, Velvet bean

Prevalence and compatibility of high risk factors of perinatal losses in the cities of Azerbaijan

Aim. To conduct a comparative assessment of the prevalence and compatibility of high risk factors of perinatal losses in various cities of Azerbaijan.Methods. The study was conducted by continuous coverage of all cases of completed pregnancies at gestational age after 12 full weeks. The women were divided into groups according to age, the counting number of pregnancy and childbirth, birth-spacing interval. Sample size was 6544 cases in the city Sumgait, 4930 in the city of Ganja, in the city of Shirvan 2066.Results.In the city of Sumgait, the proportion of childbirths before the age of 18 years was 0.3±0.07%. In Ganja, this figure was higher by more than 19 times (5.9±0.34%). In the provincial city of Shirvan, proportion of childbirths before the age of 18 years (13.0±0.74%) was higher by more than 43 times in comparison with Sumgait, and 2.2 times more than in Ganja. 5.0±0.27% of childbirths in Sumgait, 6.8±0.36% in Ganja and 7.7±0.59% in Shirvan were registered in women older than 34 years. The differences in indicators between Sumgait and Ganja, Sumgait and Shirvan are statistically significant (pConclusion. The compatibility and prevalence of the high risk factors of perinatal losses have regional characteristics that should be considered when planning preventive measures and monitoring.

The Effects of Three Spacing Methods on Students’ Mid- to Long-term Retention of Lexis

This article investigates the effect that six different lexical spacing interval schedules had on Japanese university students’ retention of lexis on a translation test completed in the first and last lessons of a 15-lecture course. Two schedules used an expanded spaced retrieval (ESR) technique, two employed a uniform spaced retrieval (USR) technique, and two were based on massed retrieval (MR) methods. It was found that the ESR and USR schedules had greater positive effects on student performance than MR. It is also posited that the challenging learning conditions created by expanding the intervals between the initial encoding of a lexical item and subsequent retrieval attempts can positively affect students’ retention rates and overall learning experiences. Consequently, it is suggested that teachers and curriculum developers implement ESR and USR techniques more when planning and adapting materials. 本論は、日本の大学生が全15回の講義の初回と最終回に行う訳の試験での語彙定着力に、6つの異なる語彙分散間隔スケジュールがどのような効果を与えるかを調査したものである。2つで間隔伸張検索（ESR: expanded spaced retrieval）法を使用し、別の2つで均一間隔検索(USR: uniform spaced retrieval) 法、残りの2つは集中検索 (MR: massed retrieval) 法を用いた。結果としてESRとUSRは、MRよりも学生の成績により良い影響を与えた。また、語彙の最初の発信と次の検索の間隔を延ばすという厳しい学習条件が、学生の語彙の定着率と総体的な学習経験に良い影響を与えると仮定される。そのため、教師やカリキュラム作成者は、教材の教授予定を作成する際、より多くのESRやUSR法を取り入れるよう推奨したい。