Prediction of Frost Hardiness in Douglas Fir Seedlings by Measuring Electrical Impedance in Stems at Different Frequencies

1973 ◽  
Vol 3 (2) ◽  
pp. 256-264 ◽  
Author(s):  
R. van den Driessche
Keyword(s):  
Survival Data ◽  
Electrical Impedance ◽  
Douglas Fir ◽  
Frost Hardiness ◽  
Impedance Measurements ◽  
Temperature Regimes ◽  
Before And After ◽  
Post Test ◽  
Different Levels ◽  
Short Days

Frost hardiness of Douglas fir (Pseudotsugamenziesii Mirb. Franco.) plants was assessed by a range of freezing tests in three experiments. In experiments 1 and 2 plants were grown in different temperature regimes, under short days, for 8 weeks to induce different levels of frost hardiness. In experiment 3, plants remained in the open and were sampled on 21 occasions through one year.Comparison of stem impedance measurements made at 1 kHz, 4.5 kHz, and 1 MHz, before and after freezing tests in experiments 1 and 2, indicated survival of individual plants was well predicted by post test measurements. The postfreezing test 1 kHz/1 MHz ratio distinguished between dead and surviving plants with the smallest number of measurements. Both this ratio and 4.5 kHz impedance provided similar conclusions about treatment effects, which agreed satisfactorily with conclusions from survival data. Impedance ratios of 1 kHz/1 MHz measured in stems after freezing tests accurately predicted survival in experiment 3. Seasonal changes in ratio, determined after freezing to a particular temperature, paralleled seasonal change in plant frost hardiness and was significantly correlated with exposure to cold during 14 days prior to measurement.

Carbohydrate reserves and root growth potential in Douglas-fir seedlings before and after cold storage

1982 ◽  
Vol 12 (4) ◽  
pp. 905-912 ◽  
Author(s):  
Gary A. Ritchie
Keyword(s):  
Root Growth ◽  
Cold Storage ◽  
Drought Resistance ◽  
Dry Weight ◽  
Douglas Fir ◽  
Growth Potential ◽  
Frost Hardiness ◽  
Root Growth Potential ◽  
Carbohydrate Reserves ◽  
Before And After

Carbohydrate reserves and root growth potential (RGP) of 2 + 0 Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings were monitored through a lifting season and during dark, cold storage. Concentrations of total nonstructural carbohydrate and extractable sugars in root and stem tissues remained relatively constant through winter, while foliar sugars showed a sharp midwinter peak at about 195 mg•g−1 dry weight. RGP was lowest in November and March and peaked in January. During storage at +2 and −1 °C, carbohydrates were depleted in all tissues through respiratory consumption. In contrast, RGP increased during the first 6 months in storage and then fell rapidly. The results do not support the view that changes in RGP are driven by changes in carbohydrate concentrations. Storage may affect frost hardiness and drought resistance through its effect on sugar concentrations.

scholarly journals Apple Bruise Detection by Electrical Impedance Measurement

HortScience ◽  
2000 ◽  
Vol 35 (1) ◽  
pp. 104-107 ◽  
Author(s):  
Phillipa J. Jackson ◽  
F. Roger Harker
Keyword(s):  
Electrical Impedance ◽  
Impedance Measurement ◽  
Apple Fruit ◽  
Fruit Weight ◽  
Electrical Impedance Spectroscopy ◽  
Apple Cultivar ◽  
Impedance Measurements ◽  
Before And After ◽  
Electrical Impedance Measurement ◽  
Further Development

Electrical impedance was used to determine the extent of tissue damage that occurred as a result of bruising of apple fruit (Malus ×domestica Borkh, cvs. Granny Smith and Splendour). Impedance measurements were made before and after bruising. Plots of reactance against resistance at 36 spot frequencies between 50 Hz and 1 MHz traced a semicircular arc, which contracted in magnitude after bruising. A number of characteristics of these curves were then related to bruise weight. The change in resistance that occurred as a result of fruit impact (ΔR50Hz) was the best predictor of bruise weight, with r2 values up to 0.71. Before bruising, resistance of fruit was higher in `Splendour' than in `Granny Smith' (P < 0.001), and at 0 °C than at 20 °C (P < 0.001), but was not influenced by fruit weight. The influence of apple cultivar and temperature on electrical impedance may cause difficulties when implementing these measurements in a commercial situation. However, further development of electrical impedance spectroscopy methodologies may result in convenient research techniques for assessing bruise weight without having to wait for browning of the flesh.

scholarly journals Measurement of Frost-hardiness in Douglas Fir at Three Nurseries by an Electrical Method

1970 ◽  
Vol 46 (1) ◽  
pp. 65-66
Author(s):  
R. van den Driessche
Keyword(s):  
Electrical Impedance ◽  
Douglas Fir ◽  
Frost Hardiness ◽  
Impedance Method ◽  
Electrical Method

Frost-hardiness changes in three Douglas fir provenances at each of three nurseries were followed from September, 1968, to April, 1969, by measuring electrical impedance of stems. Nursery had a greater effect on hardiness than provenance, with seedlings at one nursery reaching the same level of hardiness two weeks earlier than those at another nursery. Detection of these hardiness differences shows the practical value of the impedance method for measuring frost-hardiness.

scholarly journals Influence of Autonomic Control on the Specific Intermittent Performance of Judo Athletes

2018 ◽  
Vol 64 (1) ◽  
pp. 99-109
Author(s):  
Bruno T. Campos ◽  
Eduardo M. Penna ◽  
João G.S. Rodrigues ◽  
Mateus Diniz ◽  
Thiago T. Mendes ◽  
...  
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
Training Experience ◽  
Specific Performance ◽  
Before And After ◽  
Post Test ◽  
Judo Athletes ◽  
The Mean ◽  
Hrv Analysis ◽  
Different Levels

Abstract Judo is a high-intensity intermittent combat sport which causes cardiac adaptations both morphologically and related to the autonomic nervous system (ANS). Therefore, this study aims to verify the correlation between heart rate variability (HRV) at rest with performance in the Special Judo Fitness Test (SJFT) and whether groups with different RR values at rest show different performance in the SJFT and during post-test recovery. Sixteen judo athletes with 7.2 ± 3.9 years of training experience participated in the study. Before and after the SJFT execution HRV and lactate measurements were conducted. For HRV analysis, we used the mean interval RR, the standard deviation of the RR interval (SDNN), the root mean square of successive differences in RR intervals (RMSSD), the low frequency (LF) and high frequency (HF) in normalized and absolute units. The sample was split into two groups (low RR and high RR) to verify if this variable could differentiate between specific performance. For the SDNN, a significant and moderate correlation (r = 0.53) was found with the total number of throws and throws in the series A (r = 0.56) and B (r = 0.54) and for the RMSSD a correlation with throws during series B (r = 0.59) in the SJFT. However, the groups did not differ in performance and recovery. Therefore, HRV is related to intermittent judo performance; however, it cannot differentiate between judokas at different levels of performance.

Electrical impedance studies of stem tissue of Solanum clones during cooling

1972 ◽  
Vol 50 (7) ◽  
pp. 1547-1554 ◽  
Author(s):  
R. E. Hayden ◽  
L. Dionne ◽  
D. S. Fensom
Keyword(s):  
Electrical Impedance ◽  
Freezing Point ◽  
Specific Resistance ◽  
Frost Hardiness ◽  
Cooling Curves ◽  
Stem Tissue ◽  
Impedance Measurements ◽  
Recovery Curve ◽  
Temperature Recovery ◽  
Selection Of

Specific electrical impedance measurements made on the stems or petioles of four varieties of Solanum were found to discriminate various clones when the plants were grown and tested under carefully controlled conditions. Frost hardiness of clones was related to the depression of the freezing point in the absence of supercooling, to the specific resistance at 4.4 °C, to the slope of the log impedance – temperature cooling curves, and to the position of the temperature recovery curve after chilling. The technique appears to be potentially useful for selection of frost resistant clones in breeding for this property.

Clinically Meaningful Change

Methodology ◽  
2019 ◽  
Vol 15 (3) ◽  
pp. 97-105
Author(s):  
Rodrigo Ferrer ◽  
Antonio Pardo
Keyword(s):  
Effect Size ◽  
False Negative ◽  
False Negative Rate ◽  
Point Of View ◽  
Skewed Distribution ◽  
Effect Sizes ◽  
False Negatives ◽  
Large Size ◽  
Before And After ◽  
Post Test

Abstract. In a recent paper, Ferrer and Pardo (2014) tested several distribution-based methods designed to assess when test scores obtained before and after an intervention reflect a statistically reliable change. However, we still do not know how these methods perform from the point of view of false negatives. For this purpose, we have simulated change scenarios (different effect sizes in a pre-post-test design) with distributions of different shapes and with different sample sizes. For each simulated scenario, we generated 1,000 samples. In each sample, we recorded the false-negative rate of the five distribution-based methods with the best performance from the point of view of the false positives. Our results have revealed unacceptable rates of false negatives even with effects of very large size, starting from 31.8% in an optimistic scenario (effect size of 2.0 and a normal distribution) to 99.9% in the worst scenario (effect size of 0.2 and a highly skewed distribution). Therefore, our results suggest that the widely used distribution-based methods must be applied with caution in a clinical context, because they need huge effect sizes to detect a true change. However, we made some considerations regarding the effect size and the cut-off points commonly used which allow us to be more precise in our estimates.

Perbedaan Pengetahuan Siswa Tentang Penyakit Hepatitis A Sebelum Dan Sesudah Penyuluhan Di MTsN 02 Bondowoso Tahun 2015

2017 ◽  
Vol 4 (2) ◽  
pp. 14
Author(s):  
Putri Megasari
Keyword(s):  
Hepatitis A ◽  
Hepatitis Virus ◽  
Sampling Technique ◽  
Mean Value ◽  
Test Design ◽  
The World ◽  
Before And After ◽  
Post Test ◽  
The Mean ◽  
Paired T Test

Hepatitis has become a health problem in the world. The hepatitis virus infected many people. According to the teacher of MTsN 02 Bondowoso more than 20 students have hepatitis A viral infection. The purpose of this research was to know the differences of students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study used pre-experimental (pre-post test design). This study used stratified random sampling technique, 127 students from 270 sample involved this research,and 143 students was excluded. We used questionnaires to collect data. The results showed that the mean value of the students 'knowledge about hepatitis A before counseling in MTsN 02 Bondowoso 2015 was 83.96 with the lowest value of 37.5 and the highest value was 100. The mean value of the students' knowledge about hepatitis A after counseling in MTsN 02 Bondowoso 2015 was 93.21 with the lowest value waf 62.5 and the highest value was 100. Paired t test showed that t (-9.07) > t table (1.98), the null hypothesis (H0) was rejected. There was a difference between students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study showed that routine counseling by healthcare provider was important to prevent hepatitis A infection.; Keywords: counseling, knowledge of students, hepatitis

Melatih Kepemimpinan Perangkat Desa Kebonharjo Kulonprogo: Membangun Sikap Anti Korupsi

2018 ◽  
Vol 1 ◽  
pp. 107
Author(s):  
Adi Heryadi ◽  
Evianawati Evianawati
Keyword(s):  
Transformational Leadership ◽  
Data Collection ◽  
Paired Samples ◽  
Significant Difference ◽  
Before And After ◽  
Post Test ◽  
Sample Test ◽  
Corruption Perception ◽  
Measuring Tool

This study aims to prove whether transformational leadership training is effective for building anti-corruption attitudes of villages in Kebonharjo village, subdistrict Samigaluh Kulonprogo. This research is an experimental research with one group pre and posttest design.Subject design is 17 people from village of 21 candidates registered. Measuring tool used in this research is the scale of anti-corruption perception made by the researcher referring to the 9 anti-corruption values with the value of reliability coefficient of 0.871. The module used as an intervention made by the researcher refers to the transformational leadership dimension (Bass, 1990). The data collected is analyzed by statistical analysis of different test Paired Sample Test. Initial data collection results obtained sign value of 0.770 which means> 0.05 or no significant difference between anti-corruption perception score between before and after training. After a period of less than 1 (one) month then conducted again the measurement of follow-up of the study subjects in the measurement again using the scale of anti-corruption perception. The results of the second data collection were analysed with Paired Samples Test and obtained the value of 0.623 sign meaning p> 0.05 or no significant difference between post test data with follow-up data so that the hypothesis of this study was rejected.

Efektifitas Pendidikan Kesehatan Dengan Metode Ceramah Tentang Vulva Hygiene Terhadap Perilaku Merawat Vulva Hygiene Saat Menstruasi Pada Remaja Putri Kelas VII Di SMPN 1 Gondang Mojokerto

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Titin Dwi Ernawati ◽  
Nikhen Fitrianingtyas Harni ◽  
Jinnani Firdausiyah
Keyword(s):  
Health Education ◽  
Young Women ◽  
Sampling Technique ◽  
Mean Value ◽  
Measurement Tool ◽  
Test Design ◽  
Average Behavior ◽  
Lecture Method ◽  
Before And After ◽  
Post Test

ABSTRAKWanita muda cenderung memiliki perilaku buruk pada kebersihan selama menstruasi. Ketika reproduksi basah dan basah, maka akan meningkatkan keasaman memfasilitasi pertumbuhan jamur. Kondisi seperti gatal pada vulva, area eksternal biasanya terjadi pada wanita muda di masa menstruasi. Perilaku seseorang dipengaruhi oleh tingkat pendidikan dan pengetahuan. Pengetahuan seseorang tentang sesuatu dapat menyebabkan perubahan perilaku. Tujuan penelitian ini adalah untuk menganalisis efektivitas pendidikan kesehatan dengan metode ceramah dalam merawat kebersihan vulva terhadap perilaku kebersihan vulva saat menstruasi pada wanita muda di kelas VII di SMPN 1 Gondang Mojokerto.Jenis penelitian ini adalah pre eksperimental One Group Pre-Post Test Design. Populasi adalah wanita muda di kelas VII di SMPN 1 Gondang Mojokerto. Teknik pengambilan sampel menggunakan total sampling dan diperoleh 21 sampel wanita muda. Alat ukur yang digunakan dalam penelitian ini adalah kuesioner. Analisis data dengan membandingkan perilaku rata-rata memperlakukan kebersihan vulva selama menstruasi sebelum dan sesudah kuliah pendidikan kesehatan.Hasil penelitian sebelum pengobatan (pre-test) menunjukkan nilai rata-rata 9,000 sedangkan penelitian setelah perawatan (post test) menunjukkan nilai rata-rata 14,190. Ada perubahan dalam perilaku rata-rata memperlakukan kebersihan vulva selama menstruasi wanita muda sebelum dan sesudah kuliah pendidikan kesehatan di 5.190.Berdasarkan hasil pendidikan kesehatan dengan metode ceramah efektif untuk meningkatkan perawatan perilaku untuk kebersihan vulva selama menstruasi pada wanita muda. Kuliah pendidikan kesehatan tentang kebersihan vulva dapat digunakan sebagai salah satu cara efektif untuk memperbaiki perilaku kebersihan yang buruk selama menstruasi pada wanita muda.Kata kunci: pendidikan kesehatan, perilaku, kebersihan vulva ABSTRACTYoung women tend to have bad behavior on hygiene during menstruation. When reproduction moist and wet, it will increase the acidity facilitate mold growth. Conditions such as itching of the vulva, the external area usually occurs during young women in the menstrual period. Person's behavior is influenced by the level of education and knowledge. One's knowledge about something can cause behavioral changes. The purpose of the study was to analyze the effectiveness of health education with the lecture method of treating vulva hygiene on the behavior of vulva hygiene during menstruation in young women in class VII at SMPN 1 Gondang MojokertoType of research is pre experimental One Group Pre-Post Test Design. The population was young women in class VII at SMPN 1 Gondang Mojokerto. Sampling technique used total sampling and obtained 21 samples of young women. Measurement tool used in the study was questionnaire. Analysis of the data by comparing the average behavior of treating vulva hygiene during menstruation before and after the health education lecture.The results of the study before treatment (pre-test) showed a mean value of 9,000 while the study after treatment (post test) showed a mean value of 14,190. There is a change in the average behavior of treating vulva hygiene during menstruation young women before and after the health education lecture at 5,190.Based on the results of health education with the lecture method effectively to improved behavioral care for vulva hygiene during menstruation in young women. Health education lecture about hygiene vulva can be used as one of the effective ways to improve the behavior of poor hygiene during menstruation in young women.Key Words: health education, behaviour, vulva hygiene 

Sign in / Sign up

Export Citation Format

Share Document