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Simões, Maurício dos Santos, Jansle Vieira Rocha y Rubens Augusto Camargo Lamparelli. "Growth indices ans productivity in sugarcane". Scientia Agricola 62, n.º 1 (enero de 2005): 23–30. http://dx.doi.org/10.1590/s0103-90162005000100005.
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A knowledge about the temporal development of agronomic variables in sugarcane is a very important aspect for the development of crop yield prediction models using remote sensing, and further studies are still needed. This paper describes the temporal evolution of sugarcane biophysical parameters, such as total biomass, leaf area index, number of plants per meter, and productivity. During two seasons, a commercial field in Araras/SP, planted with variety SP80-1842, on the 4th and 5th cuts, was monitored on eight different dates, and data were obtained for 2 m of sugarcane in three crop rows at 18 sampling points. Linear and multiple regression analyses were used to study growth analysis and to correlate agronomic variables (leaf area index and number of plants per meter) with biomass and productivity. Gompertz model, a sigmoidal curve, was the best adjustment curve for total biomass and yield in relation to days after cutting (r² = 0.8987 and r² = 0.9682, respectively); number of plants and leaf area index showed best fit with a cubic exponential model and a quadratic exponential model, respectively. Total biomass and cane productivity were well correlated with LAI in the first two stages of the sugarcane cycle using linear regression. At the end of the cycle, total biomass and cane productivity were more related to number of plants, and lower r² values than in other stages were obtained by the models.
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Carrión Ordoñez, José Gonzalo, María Elisa Carrión Barreto, Gleici Da Silva Castro Perdoná y Natielle Gonçalves de Sá. "Evaluación de los índices biométricos fetales para el diagnóstico del Retardo del Crecimiento Fetal". Revista Médica del Hospital José Carrasco Arteaga 14, n.º 3 (24 de julio de 2023): 166–72. http://dx.doi.org/10.14410/2022.14.3.ao.25.
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BACKGROUND: Fetal Growth Restriction occurs when a fetus does not reach its intrauterine growth potential due to genetic and/or environmental factors; it is associated with increased perinatal mortality and morbidity and also predisposes to the development of chronic disorders in adulthood. The aim of this study was to evaluate the accuracy of the Biometric Indices: Femur Length/Abdominal Circumference (FL/AC); Transverse Cerebellar Diameter/Abdominal Circumference (TCD/AC) and Humerus, Cerebellum, Femur/Abdominal Circumference Equation (HCF/AC); in predicting fetal growth retardation. METHODS: Diagnostic tests validation study, with a universe of pregnant patients who attended the outpatient clinic of Hospital General Machala, El Oro-Ecuador, for prenatal control, between 32 and 38 weeks of gestation. The following variables were obtained: gestational dating; ultrasound fetal biometry of all the necessary parameters for the described indices calculation; fetal weight estimated by ultrasound, with cut-off point ≤ P° 10. The LH/CA and TCD/CA Indices were calculated, with cut-off points for fetal growth retardation diagnosis of ≥ 23.5 and ≥16.1 respectively. The index proposed by the authors HCF/CA was also applied, taking as cut-off point the 90th percentile: ≥ 1.063. RESULTS: The prevalence of fetal weight less P° 10 in the present study was 12.22%. The biometric index with the highest sensitivity was the HCF CA index with 70.3%; however, the highest specificity was obtained for the LF CA index with 84%. The positive predictive value of the DTC CA index was 24.7%, of the LF CA index: 27.9%, and of the HCF CA index: 31.1%. The negative predictive values found were, DTC CA: 93.9%; LF CA: 91.6% and HCF CA: 95.0%. The positive likelihood ratios obtained were: DTC CA: 2.352; LF CA: 2.781 and HCF CA: 3.25. The negative likelihood ratios were, HCF CA: 0.378, DTC CA: 0.465, LF CA: 0.661. CONCLUSION:The biometric indices for prediction of fetal growth retardation have limited positive predictive accuracy. All indices have high negative predictive accuracy. To confirm the presence of condition disease the HCF CA index has better results, as well as to confirm the absence of the condition disease; the addition of the HCF CA Index increases the predictive results; the Odds Rate obtained indicates that there is 8.595 times higher probability of a positive response, when the condition"fetus in percentile ≤ 10" is present.
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Li, Huaimin, Weipan Lin, Fangrong Pang, Xiaoping Jiang, Weixing Cao, Yan Zhu y Jun Ni. "Monitoring Wheat Growth Using a Portable Three-Band Instrument for Crop Growth Monitoring and Diagnosis". Sensors 20, n.º 10 (20 de mayo de 2020): 2894. http://dx.doi.org/10.3390/s20102894.
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An instrument developed to monitor and diagnose crop growth can quickly and non-destructively obtain crop growth information, which is helpful for crop field production and management. Focusing on the problems with existing two-band instruments used for crop growth monitoring and diagnosis, such as insufficient information available on crop growth and low accuracy of some growth indices retrieval, our research team developed a portable three-band instrument for crop-growth monitoring and diagnosis (CGMD) that obtains a larger amount of information. Based on CGMD, this paper carried out studies on monitoring wheat growth indices. According to the acquired three-band reflectance spectra, the combined indices were constructed by combining different bands, two-band vegetation indices (NDVI, RVI, and DVI), and three-band vegetation indices (TVI-1 and TVI-2). The fitting results of the vegetation indices obtained by CGMD and the commercial instrument FieldSpec HandHeld2 was high and the new instrument could be used for monitoring the canopy vegetation indices. By fitting each vegetation index to the growth index, the results showed that the optimal vegetation indices corresponding to leaf area index (LAI), leaf dry weight (LDW), leaf nitrogen content (LNC), and leaf nitrogen accumulation (LNA) were TVI-2, TVI-1, NDVI (R730, R815), and NDVI (R730, R815), respectively. R2 values corresponding to LAI, LDW, LNC and LNA were 0.64, 0.84, 0.60, and 0.82, respectively, and their relative root mean square error (RRMSE) values were 0.29, 0.26, 0.17, and 0.30, respectively. The addition of the red spectral band to CGMD effectively improved the monitoring results of wheat LAI and LDW. Focusing the problem of vegetation index saturation, this paper proposed a method to construct the wheat-growth-index spectral monitoring models that were defined according to the growth periods. It improved the prediction accuracy of LAI, LDW, and LNA, with R2 values of 0.79, 0.85, and 0.85, respectively, and the RRMSE values of these growth indices were 0.22, 0.23, and 0.28, respectively. The method proposed here could be used for the guidance of wheat field cultivation.
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Bielecki, Tomasz R., Igor Cialenco y Marcin Pitera. "Dynamic Limit Growth Indices in Discrete Time". Stochastic Models 31, n.º 3 (3 de julio de 2015): 494–523. http://dx.doi.org/10.1080/15326349.2015.1053616.
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Alexeev, Alexander G. y Mikhail V. Sokolov. "A theory of average growth rate indices". Mathematical Social Sciences 71 (septiembre de 2014): 101–15. http://dx.doi.org/10.1016/j.mathsocsci.2014.05.004.
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Jain, R. C., R. Agrawal y M. P. Jha. "Use of Growth Indices in Yield Forecast". Biometrical Journal 27, n.º 4 (1985): 435–39. http://dx.doi.org/10.1002/bimj.4710270415.
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Kakade, Vikas Chintaman y Anil Prabhakar Mokashi. "Development of Local Percentile Growth Charts of Children between Birth to Ten Years". International Journal of Research and Review 8, n.º 11 (11 de noviembre de 2021): 26–31. http://dx.doi.org/10.52403/ijrr.20211105.
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Growth pattern of human population changes with time and place. Particularly developing countries, country like India, is in a stage of nutritional transition hence it is necessary to update growth references regularly. The present study is carried out on 0-10 years from Baramati from Pune district of Maharashtra. We considered that children from maternity homes, BCG camps, well baby clinics, immunization camps, private clinics, ‘Anganwadis and Balwadis’, Nurseries’ and schools etc. Our study shows that growth performance of Anthropometric indices for Baramati children is much less than National Centre of Health Statistics (NCHS) and slightly less than Indian Council of Medical Research ICMR and Affluent Indians (AI). We have proposed growth charts for Baramati region to monitor growth parameters. Keywords: Anthropometric Indices, NCHS, ICMR, AI.
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Naik, M. Tagore, D. Srihari, A. V. D. Dorajeerao, K. Sasikala, K. Umakrishna y D. R. S. Suneetha. "Growth Indices Influenced by Plant Growth Regulators in Seed Cluster Bean". International Journal of Current Microbiology and Applied Sciences 7, n.º 11 (10 de noviembre de 2018): 3104–17. http://dx.doi.org/10.20546/ijcmas.2018.711.356.
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Petrin, Rumen. "GROWTH-RATE INDICES AND GROWTH TYPE COEFFICIENTS IN HEIGHT OF BROADLEAVES FOREST STANDS". Forestry Engineering Journal 12, n.º 4 (1 de enero de 2023): 47–59. http://dx.doi.org/10.34220/issn.2222-7962/2022.4/4.
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Based on published data about the growth in height of model and other stands of seed-tree common beech, oak, deciduous and coppice deciduous stands have their rates of growth been investigated within one and the same age interval. New indicators have been used for establishing the respective growth rates – growth-rate indi-ces. New coefficients have been suggested for estimating the types of growth, and their applicability to use has been proved as these coefficients have been compared with the zero natural indicators of types of growth. A high level of correlation has been found with that. An analysis was made of the height growth rates of the studied stands based on their index curves. Further on, by applying the new coefficients of types of growth, the values and intervals of growth-rate indices according to types of growths, have been found for the stands of the tree spe-cies investigated. It has been concluded thatthe coefficients of types of growth, as well as the growth-rate indices, are rather convenient instruments for finding differences in the rates and types of the growth of forest stands in height.
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Kwesi Nyarko, Peter y Christiana Cynthia Nyarko. "Modelling Forest Growth Indices on Vegetation Pattern Formation". American Journal of Applied Mathematics 9, n.º 4 (2021): 108. http://dx.doi.org/10.11648/j.ajam.20210904.13.
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Bishop, R. E., J. J. Torres y R. E. Crabtree. "Chemical composition and growth indices in leptocephalus larvae". Marine Biology 137, n.º 2 (15 de septiembre de 2000): 205–14. http://dx.doi.org/10.1007/s002270000362.
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Shi, Xiaopei, Richard Smith, Colin Seymour y Carmel Mothersill. "Ra-226 bioaccumulation and growth indices in fish". International Journal of Radiation Biology 93, n.º 6 (14 de marzo de 2017): 617–26. http://dx.doi.org/10.1080/09553002.2017.1297900.
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Gupta, R. K. "NOAA/AVHRR vegetation indices as agrometeorological growth parameter". Advances in Space Research 13, n.º 5 (mayo de 1993): 223–32. http://dx.doi.org/10.1016/0273-1177(93)90549-q.
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Daniels, Richard F., Harold E. Burkhart y Terry R. Clason. "A comparison of competition measures for predicting growth of loblolly pine trees". Canadian Journal of Forest Research 16, n.º 6 (1 de diciembre de 1986): 1230–37. http://dx.doi.org/10.1139/x86-218.
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Five families of competition indices were evaluated and compared on the basis of simple correlation with loblolly pine individual tree growth and multiple correlation with growth in the presence of other tree and stand attributes. The family of distance-independent indices included various relative size measures in the form of tree size to mean size ratios. Crown ratio was also included as a distance-independent measure. The four families of distance-dependent indices included various influence area overlap indices, distance-weighted size ratio indices, Spurr's point density, and Brown's point density or area potentially available (APA). All indices were significantly correlated with dbh and basal area growth. The relative size ratio indices, crown ratio, Spurr's point density, and several APA variations were judged best in simple correlations after accounting for tree size and stand density. The best distance-dependent indices had little if any advantage, either in simple or multiple correlation, over the best distance-independent indices. However, the point density index of Spurr and especially APA contributed significantly to growth prediction even in the presence of tree size, stand density, and the distance-independent size ratio and crown ratio indices. Further, APA had the highest partial correlation when all variables were included in this multiple correlation. It was concluded the APA would be a good index for growth prediction models when other tree and stand attributes are already known.
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Shi, Haijin y Lianjun Zhang. "Local Analysis of Tree Competition and Growth". Forest Science 49, n.º 6 (1 de diciembre de 2003): 938–55. http://dx.doi.org/10.1093/forestscience/49.6.938.
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Abstract The relationships between the Local Indicator of Spatial Association (LISA) and traditional tree competition indices and individual tree growth were investigated. The results show that like most of the competition indices, LISA had moderate correlations with tree basal area growth. For predicting the tree basal area growth in a linear regression model, the local Gi performed better than many (73%) competition indices at a plot aggregation level and had higher explanatory power than most (91%) competition indices at an individual plot level. LISA also had linear and strong relationships with some traditional competition indices, such as the Lorimer index. The relationships were stronger (ρ >0.90) at an individual plot level than for all plots combined (ρ>0.75). More importantly, LISA could be statistically tested to identify local clusters of trees of similar or dissimilar sizes, even though there was no discernible pattern as summarized by a global statistic of spatial autocorrelation. These significant “hot spots” (clusters of trees of similar sizes) or “cold spots” (clusters of trees of dissimilar sizes) indicated subareas in a forest stand where the competition among trees may be more severe than the average. Therefore, LISA can replace the traditional competition indices for exploring the competitive status of neighboring trees, investigating the relationships between tree competition and growth, and estimating individual tree growth as a predictor variable in a forest growth simulator. The hot spots or cold spots identified by LISA provide useful information for the design of silvicultural and management treatments, such as selection thinning. Furthermore, LISA can be readily incorporated into visualization tools, such as a geographic information system (GIS), because it provides georeferenced information at a local level.
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Tomé, Margarida y Harold E. Burkhart. "Distance-Dependent Competition Measures for Predicting Growth of Individual Trees". Forest Science 35, n.º 3 (1 de septiembre de 1989): 816–31. http://dx.doi.org/10.1093/forestscience/35.3.816.
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Abstract Modified distance-dependent competition indices were developed for predicting tree growth in plantations. These modified indices adjust the growth of an average tree up and down depending on the size of competitors as compared to the subject tree. A neighbor larger than the subject tree--dominant neighbor--places the subject tree at a competitive disadvantage, whereas a smaller neighbor--suppressed competitor--places it at a competitive advantage. Dead neighbors are included as a special kind of suppressed neighbor. Based on this philosophy, new versions and modifications of distance-weighted size ratio and area overlap indices were developed and compared to some previously published indices. Data from a spacing study established in eucalypt plantations in Portugal were used for the empirical aspects of this study. Single correlations with growth, on a spacing X age basis, were generally higher for the modified indices than for their original unmodified counterparts. Modified indices, in conjunction with stand-level variables, also performed well in multiple linear regression equations for predicting growth of individual trees. For. Sci. 35(3):816-831.
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Nucci, Anita M., Jorge Reyes, Jane Anne Yaworski, George Mazariegos, Natalie Beserock y Edward M. Barksdale. "Serum growth factors and growth indices pre- and post-pediatric intestinal transplantation". Journal of Pediatric Surgery 38, n.º 7 (julio de 2003): 1043–47. http://dx.doi.org/10.1016/s0022-3468(03)00188-x.
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LeBlanc, David C. "Relationships between breast-height and whole-stem growth indices for red spruce on Whiteface Mountain, New York". Canadian Journal of Forest Research 20, n.º 9 (1 de septiembre de 1990): 1399–407. http://dx.doi.org/10.1139/x90-185.
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This paper describes relationships between tree growth indices based on ring width measurements at 1.4 m aboveground and indices derived from whole-stem analysis for red spruce (Picearubens Sarg.) in a high-elevation spruce-fir forest on Whiteface Mountain, New York. Coefficients of determination for linear regressions between mean, standardized chronologies for breast-height ring width versus whole-stem ring width and basal area increment versus annual volume increment are 0.89 and 0.93, respectively. However, substantial variability is apparent in breast-height versus whole-stem relationships for individual trees, particularly for unstandardized growth indices. Also, relationships between unstandardized growth indices exhibit temporal instability associated with individual tree maturation and stand dynamics. Nonetheless, strong relationships between mean standardized chronologies of breast-height and whole-stem growth indices validate the use of breast-height growth indices to represent year-to-year variation in mean growth performance of red spruce. A volume-equation-based procedure is described that provides better dendrochronological estimates of annual volume increment than estimates based on basal area increment alone.
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Firmino, Paulo Neves, Margarida Tomé y Joana Amaral Paulo. "Do Distance-Dependent Competition Indices Contribute to Improve Diameter and Total Height Tree Growth Prediction in Juvenile Cork Oak Plantations?" Forests 14, n.º 5 (22 de mayo de 2023): 1066. http://dx.doi.org/10.3390/f14051066.
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Competition indices may improve tree growth modelling in high-density stands, found often in new cork oak plantations. Distance-dependent competition indices have hardly been considered for juvenile cork oak plantations since existing models were developed for low-density mature stands. This study aims at inspecting the potential of including distance-dependent competition indices into diameter at breast height (d) and total height (h) growth models for Quercus suber L., comparing several distance-dependent and distance-independent competition indices. Annual d and h growth were modelled with linear and non-linear growth functions, formulated as difference equations. Base models were initially fitted considering parameter estimates depending only on site index (S) and/or stand density (N). They were refitted, testing the significance of adding each competition index to the model parameters. Selected models included the best-performing distance-dependent or -independent competition indices as additional predictors. Best base d and h growth models showed a modelling efficiency (ef) of ef = 0.9833 and ef = 0.9900, respectively. Adding a distance-dependent competition index slightly improved growth models, to an ef = 0.9851 for d and ef = 0.9902 for h. Best distance-dependent competition indices slightly overperformed distance-independent ones in diameter growth models. Neither S nor N were included on best fitted models. If inter-tree competition is present in juvenile undebarked cork oak plantations, it does not yet strongly impact individual tree growth, which may diminish the importance of using, at this stage, more complex spatially explicit competition indices on predicting individual tree growth.
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Sun, Shuaichao, Quang V. Cao y Tianjian Cao. "Evaluation of distance-independent competition indices in predicting tree survival and diameter growth". Canadian Journal of Forest Research 49, n.º 5 (mayo de 2019): 440–46. http://dx.doi.org/10.1139/cjfr-2018-0344.
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Competition indices play a significant role in modeling individual-tree growth and survival. In this study, six distance-independent competition indices were evaluated using 200 permanent plots of loblolly pine (Pinus taeda L.). The competition indices were classified into three families: (1) size ratios, which include diameter ratio and basal area ratio; (2) relative position indices, which include basal area of larger trees (BAL) and tree relative position based on the cumulative distribution function (CDF); and (3) partitioned stand density index and relative density. Results indicated that different families of competition indices were suitable for different tree survival or diameter growth prediction tasks. The diameter ratio was superior for predicting tree survival, whereas the relative position indices (BAL and CDF) performed best for predicting tree diameter growth, with CDF receiving the highest rank.
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娟 (Ma Wei Juan), 马玮. "Growth surveillance indices and Kashin-Beck Disease in children". Journal of Medicine and Life 15, n.º 2 (febrero de 2022): 292–97. http://dx.doi.org/10.25122/jml-2021-0125.
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Selenium, manganese, and calcium are necessary elements for maintaining normal growth and skeleton formation. Kashin-Beck disease mostly occurs in children, resulting in deformities, dwarfism, and disabilities. Selenium deficiency was considered a risk factor in China, while manganese was reportedly involved in it in Russia. Single-element regulation cannot be used in diagnosis because of unclear boundaries in patients compared to healthy individuals. In this study, new indices of elements were designed to predict the status of disease. MS (Mn/Se), CS (Ca’/Se), and MC (Mn/Ca’) values were designed, and prediction formulas were generated by comparing healthy children with those with Kashin-Beck disease via multiple linear regression analysis and discriminant analysis. In the disease group, 42.86% of patients had positive MS, CS, and MC values, and 57.14% of patients had positive MS and CS values. In the treatment group, the patients presented improved indices. In the prediction group, subjects with negative clinical criteria features were predicted by new indices, and 26.67% of them presented with positive MS, CS, and MC values, whereas 40.00% had positive MS and CS values. The 3D model of MS, CS, and MC refers to the setup of elements. The MS, CS, and MC indices are helpful in disease prediction, diagnosis, prognosis, and surveillance. The distribution model of the indices could serve in the growth surveillance of children.
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Biging, Gregory S. y Matthias Dobbertin. "Evaluation of Competition Indices in Individual Tree Growth Models". Forest Science 41, n.º 2 (1 de mayo de 1995): 360–77. http://dx.doi.org/10.1093/forestscience/41.2.360.
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Abstract In this paper we explore how well distance-independent competition measures explain variation in the height and diameter squared growth of individual conifer trees. We investigated a number of stand-level density indices and individual tree competition indices which incorporate tree sizes, but do not include location. We model growth of individual trees as potential growth reduced by competition. The reduction in mean square error relative to no competition index was used to judge performance of each competition index which varies by species and growth component (height or diameter squared growth). Results are summarized by species and type of competition index. The distance-independent measures are also compared to selected distance-dependent measures shown in recent research work to perform well for conifer species. It was found that a new class of distance-independent indices that includes estimated crown parameters performs on par with the best distance-dependent competition indices when used in conjunction with models of individual tree height and diameter squared growth. For. Sci. 41(2):360-377.
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Ewuola, E. O., B. A. Omoniyi y J. O. Omotoso. "Growth indices, haematological and serum biochemical response of weaned rabbits fed growth promoters". Nigerian Journal of Animal Production 41, n.º 2 (10 de enero de 2021): 61–70. http://dx.doi.org/10.51791/njap.v41i2.2446.
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The use of feed additives and plant extracts in rabbit husbandry offers an acceptable way to improve welfare, health and meat quality of rabbits as alternative to the use of antibiotics. In a six-week feeding trial, growth rate, nutrient digestibility, haematology and serum biochemical indices of weaned rabbits fed dietary prebiotics and probiotics as natural growth promoters were investigated. Thirty–two weaned crossbred rabbits of 6–week old with average weight of 446.75±32.1g were randomly allotted to 4 dietary treatments. Diet 1 served as the control without test ingredients while diets 2 (prebiotics-Biotronic®at 4kg/ton), 3 (probiotics- Biovet®-YC at 500g/ton) and 4 (symbiotics: Biotronic® SE and Biovet®-YC) were other treatments. Feed intake, weight gain, feed conversion ratio, feed efficiency, nutrient digestibility, haematological and serum biochemical variables were monitored. The design of the experiment was a completely randomized design. Feed intake was similar among dietary treatments while weight gain of rabbits fed diets 1, 2 and 3 was the same but significantly (p<0.05) higher than rabbits fed diet 4. Feed conversion ratio was not significantly influenced by the treatments. Feed efficiency was significantly (p<0.05) higher in rabbits fed symbiotic supplemented diets compared to others. The dry matter, crude protein, crude fibre, ash, nitrogen free extracts and ether extract digestibility were significantly (p<0.05) higher in rabbits fed diets 2 and 3 than those on diets 4 and the control. Packed cell volume and haemoglobin were significantly (p<0.05) higher in rabbits fed diets 3 and 4 than diets 1 and 2. Erythrocyte and leukocyte count were not significantly different among the treatments. Total protein, albumin and globulin examined revealed that they were not significantly influenced by the dietary treatments, however, alkaline phosphatase was significantly (p<0.05) higher in rabbits fed test diets than the control. Biotronic®SE and Biovet® -YC in this study had a potential to enhance growth in rabbit when used as feed additive without any adverse effect on health status of the animal.
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Tao, Huilin, Haikuan Feng, Liangji Xu, Mengke Miao, Huiling Long, Jibo Yue, Zhenhai Li, Guijun Yang, Xiaodong Yang y Lingling Fan. "Estimation of Crop Growth Parameters Using UAV-Based Hyperspectral Remote Sensing Data". Sensors 20, n.º 5 (27 de febrero de 2020): 1296. http://dx.doi.org/10.3390/s20051296.
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Above-ground biomass (AGB) and the leaf area index (LAI) are important indicators for the assessment of crop growth, and are therefore important for agricultural management. Although improvements have been made in the monitoring of crop growth parameters using ground- and satellite-based sensors, the application of these technologies is limited by imaging difficulties, complex data processing, and low spatial resolution. Therefore, this study evaluated the use of hyperspectral indices, red-edge parameters, and their combination to estimate and map the distributions of AGB and LAI for various growth stages of winter wheat. A hyperspectral sensor mounted on an unmanned aerial vehicle was used to obtain vegetation indices and red-edge parameters, and stepwise regression (SWR) and partial least squares regression (PLSR) methods were used to accurately estimate the AGB and LAI based on these vegetation indices, red-edge parameters, and their combination. The results show that: (i) most of the studied vegetation indices and red-edge parameters are significantly highly correlated with AGB and LAI; (ii) overall, the correlations between vegetation indices and AGB and LAI, respectively, are stronger than those between red-edge parameters and AGB and LAI, respectively; (iii) Compared with the estimations using only vegetation indices or red-edge parameters, the estimation of AGB and LAI using a combination of vegetation indices and red-edge parameters is more accurate; and (iv) The estimations of AGB and LAI obtained using the PLSR method are superior to those obtained using the SWR method. Therefore, combining vegetation indices with red-edge parameters and using the PLSR method can improve the estimation of AGB and LAI.
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Makinde, Akeem. "Sensitivity of Okra Growth Indices to Various Moisture Conditions". American Journal of Agricultural and Biological Sciences 17, n.º 1 (1 de enero de 2022): 51–57. http://dx.doi.org/10.3844/ajabssp.2022.51.57.
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Wharton, Sonia y Matthias Falk. "Climate indices strongly influence old-growth forest carbon exchange". Environmental Research Letters 11, n.º 4 (1 de abril de 2016): 044016. http://dx.doi.org/10.1088/1748-9326/11/4/044016.
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Yihyun Kim, Thomas Jackson, Rajat Bindlish, Sukyoung Hong, Gunho Jung y Kyuongdo Lee. "Retrieval of Wheat Growth Parameters With Radar Vegetation Indices". IEEE Geoscience and Remote Sensing Letters 11, n.º 4 (abril de 2014): 808–12. http://dx.doi.org/10.1109/lgrs.2013.2279255.
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Yuan, Ke-Hai, Zhiyong Zhang y Lifang Deng. "Fit indices for mean structures with growth curve models." Psychological Methods 24, n.º 1 (febrero de 2019): 36–53. http://dx.doi.org/10.1037/met0000186.
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Schreyer, Paul. "Computer Price Indices and International Growth and Productivity Comparisons". Review of Income and Wealth 48, n.º 1 (marzo de 2002): 15–31. http://dx.doi.org/10.1111/1475-4991.00038.
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Kang, So-young, Chan Kook y Yong-Gyu Shin. "Physical Indices Characteristics of Water Sound Influencing Plant Growth". Journal of the Korean Society for Environmental Technology 24, n.º 6 (31 de diciembre de 2023): 374–80. http://dx.doi.org/10.26511/jkset.24.6.2.
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Maleki, Kobra, Andres Kiviste y Henn Korjus. "Analysis of Individual Tree Competition on Diameter Growth of Silver Birch in Estonia". Forest Systems 24, n.º 2 (27 de julio de 2015): e023. http://dx.doi.org/10.5424/fs/2015242-05742.
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<p><em>Aim of study:</em> The present study evaluates a set of competition indices including spatially explicit indices combined with different competitor selection approaches and non-spatially explicit competition indices. The aim was to quantify and describe the neighbouring effects on the tree diameter growth of silver birch trees.<em></em></p><p><em>Area of study:</em> Region throughout Estonia. <em></em></p><p><em>Material and methods:</em> Data from the Estonian Network of Forest Research Plots was used. After quantifying the selected indices, the best non-spatial indices and spatial indices (combined with neighbour selection methods) were separately devised into a growth model as a predictor variable to assess the ability of the diameter growth model before and after adding competition measures. To test the species-specific effect on the competition level, the superior indices were recalculated using Ellenberg’s light indicators and incorporated into the diameter growth model. <em></em></p><p><em>Main results:</em> Statistical analyses showed that the diameter growth is a function of neighbourhood interactions and spatial indices were better growth predictors than non-spatial indices. In addition, the best selections of competitive neighbours were acquired based on the influence zone and the competition elimination angle concepts, and using Ellenberg’s light values had no significant improvement in quantifying the competition effects. <em></em></p><p><em>Research highlights: </em>Although the best ranking spatial competition measures were superior to the best non-spatial indices, the differences were negligible.</p><p><strong>Keywords:</strong> Competition indices; zone of influence; stem diameter increment; <em>Betula pendula </em>Roth<em>.</em><strong></strong></p>
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Psiroukis, Vasilis, George Papadopoulos, Aikaterini Kasimati, Nikos Tsoulias y Spyros Fountas. "Cotton Growth Modelling Using UAS-Derived DSM and RGB Imagery". Remote Sensing 15, n.º 5 (22 de febrero de 2023): 1214. http://dx.doi.org/10.3390/rs15051214.
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Modeling cotton plant growth is an important aspect of improving cotton yields and fiber quality and optimizing land management strategies. High-throughput phenotyping (HTP) systems, including those using high-resolution imagery from unmanned aerial systems (UAS) combined with sensor technologies, can accurately measure and characterize phenotypic traits such as plant height, canopy cover, and vegetation indices. However, manual assessment of plant characteristics is still widely used in practice. It is time-consuming, labor-intensive, and prone to human error. In this study, we investigated the use of a data-processing pipeline to estimate cotton plant height using UAS-derived visible-spectrum vegetation indices and photogrammetric products. Experiments were conducted at an experimental cotton field in Aliartos, Greece, using a DJI Phantom 4 UAS in five different stages of the 2022 summer cultivation season. Ground Control Points (GCPs) were marked in the field and used for georeferencing and model optimization. The imagery was used to generate dense point clouds, which were then used to create Digital Surface Models (DSMs), while specific Digital Elevation Models (DEMs) were interpolated from RTK GPS measurements. Three (3) vegetation indices were calculated using visible spectrum reflectance data from the generated orthomosaic maps, and ground coverage from the cotton canopy was also calculated by using binary masks. Finally, the correlations between the indices and crop height were examined. The results showed that vegetation indices, especially Green Chromatic Coordinate (GCC) and Normalized Excessive Green (NExG) indices, had high correlations with cotton height in the earlier growth stages and exceeded 0.70, while vegetation cover showed a more consistent trend throughout the season and exceeded 0.90 at the beginning of the season.
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Urban, S. T., V. J. Lieffers y S. E. Macdonald. "Release in radial growth in the trunk and structural roots of white spruce as measured by dendrochronology". Canadian Journal of Forest Research 24, n.º 8 (1 de agosto de 1994): 1550–56. http://dx.doi.org/10.1139/x94-202.
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We used a new technique to examine the response of the trunk and structural roots of white spruce (Piceaglauca (Moench) Voss) to an increase in wind exposure. Ring widths were measured in the roots and trunks of trees located within a 120-year-old, boreal mixedwood stand (control) and at the edge of a road built through the stand 16 years before sampling (released). The observed ring widths were divided by widths predicted from regression to produce ring indices. Response indices were produced by subtracting the ring indices of control trees from those of released trees. Allocation indices were produced by subtracting the ring indices of trunks from those of roots. A final index, quantifying the change in allocation to the root and trunk after road clearing, was produced by subtracting allocation indices of control trees from those of released trees. Following the road clearing, the rate of trunk diameter growth remained unchanged for 3–9 years, while root diameter growth increased. These observations suggest that trunk growth may be suppressed for some years following road clearing as a result of increased root growth. The increase in root growth may help stabilize trees after exposure to increased wind stress by increasing the amount of root wood anchoring and supporting them.
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Xu, Hongyan, Guangsheng Chen, Hari Mohan Srivastava, Hong Li, Zuxing Xuan y Yongqin Cui. "A Study of the Growth Results for the Hadamard Product of Several Dirichlet Series with Different Growth Indices". Mathematics 10, n.º 13 (24 de junio de 2022): 2220. http://dx.doi.org/10.3390/math10132220.
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In this paper, our first purpose is to describe a class of phenomena involving the growth in the Hadamard–Kong product of several Dirichlet series with different growth indices. We prove that (i) the order of the Hadamard–Kong product series is determined by the growth in the Dirichlet series with smaller indices if these Dirichlet series have different growth indices; (ii) the q1-type of the Hadamard–Kong product series is equal to zero if p Dirichlet series are of qj-regular growth, and q1<q2<⋯<qp, qj∈N+, j=1,2,…,p. The second purpose is to reveal the properties of the growth in the Hadamard–Kong product series of two Dirichlet series—when one Dirichlet series is of finite order, the other is of logarithmic order, and two Dirichlet series are of finite logarithmic order—and obtain the growth relationships between the Hadamard–Kong product series and two Dirchlet series concerning the order, the logarithmic order, logarithmic type, etc. Finally, some examples are given to show that our results are best possible.
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Lu, Laura y Zhiyong Zhang. "How to Select the Best Fit Model among Bayesian Latent Growth Models for Complex Data". Journal of Behavioral Data Science 2, n.º 1 (23 de junio de 2022): 1–24. http://dx.doi.org/10.35566/jbds/v2n1/p2.
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Bayesian approach is becoming increasingly important as it provides many advantages in dealing with complex data. However, there is no well-defined model selection criterion or index in a Bayesian context. To address the challenges, new indices are needed. The goal of this study is to propose new model selection indices and to investigate their performances in the framework of latent growth mixture models with missing data and outliers in a Bayesian context. We consider latent growth models because they are very flexible in modeling complex data and becoming increasingly popular in statistical, psychological, behavioral, and educational areas. Specifically, this study conducted five simulation studies to cover different cases, including latent growth curve models with missing data, latent growth curve models with missing data and outliers, growth mixture models with missing data and outliers, extended growth mixture models with missing data and outliers, and latent growth models with different classes. Simulation results show that almost all proposed indices can effectively identify the true model. This study also illustrated the application of these model selection indices in real data analysis.
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Wang, Qi, Xiaokai Chen, Huayi Meng, Huiling Miao, Shiyu Jiang y Qingrui Chang. "UAV Hyperspectral Data Combined with Machine Learning for Winter Wheat Canopy SPAD Values Estimation". Remote Sensing 15, n.º 19 (22 de septiembre de 2023): 4658. http://dx.doi.org/10.3390/rs15194658.
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Chlorophyll is an important indicator for monitoring crop growth and is vital for agricultural management. Therefore, rapid and accurate estimation of chlorophyll content is important for decision support in precision agriculture to accurately monitor the SPAD (Soil and Plant Analyzer Development) values of winter wheat. This study used winter wheat to obtain canopy reflectance based on UAV hyperspectral data and to calculate different vegetation indices and red-edge parameters. The best-performing vegetation indices and red-edge parameters were selected by Pearson correlation analysis and multiple stepwise regression (MSR). SPAD values were estimated using a combination of vegetation indices, vegetation indices and red-edge parameters as model factors, two types of machine learning (ML), a support vector machine (SVM), and a backward propagation neural network (BPNN), and partial least squares regression (PLSR) for four growth stages of winter wheat, and validated using independent samples. The results show that for the same data source, the best vegetation indices or red-edge parameters for estimating SPAD values differed at different growth stages and that combining vegetation indices with red-edge parameters gave better estimates than using only vegetation indices as an input factor for estimating SPAD values. There is no significant difference between PLSR, SVM, and BPNN methods in estimating SPAD values, with better stability of the estimated models using machine learning methods. Different growth stages have a large impact on winter wheat SPAD values estimates, with the accuracy of the four growth stage models increasing in the following order: booting < heading < filling < flowering. This study shows that using a combination of vegetation indices and red-edge parameters can improve SPAD values estimates compared to using vegetation indices alone. In the future, the choice of appropriate factors and methods will need to be considered when constructing models to estimate crop SPAD values.
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Lv, Qiuna, Liyan Han, Yipeng Wan y Libo Yin. "Stock Net Entropy: Evidence from the Chinese Growth Enterprise Market". Entropy 20, n.º 10 (19 de octubre de 2018): 805. http://dx.doi.org/10.3390/e20100805.
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By introducing net entropy into a stock network, this paper focuses on investigating the impact of network entropy on market returns and trading in the Chinese Growth Enterprise Market (GEM). In this paper, indices of Wu structure entropy (WSE) and SD structure entropy (SDSE) are considered as indicators of network heterogeneity to present market diversification. A series of dynamic financial networks consisting of 1066 daily nets is constructed by applying the dynamic conditional correlation multivariate GARCH (DCC-MV-GARCH) model with a threshold adjustment. Then, we evaluate the quantitative relationships between network entropy indices and market trading-variables and their bilateral information spillover effects by applying the bivariate EGARCH model. There are two main findings in the paper. Firstly, the evidence significantly ensures that both market returns and trading volumes associate negatively with the network entropy indices, which indicates that stock heterogeneity, which is negative with the value of network entropy indices by definition, can help to improve market returns and increase market trading volumes. Secondly, results show significant information transmission between the indicators of network entropy and stock market trading variables.
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Holmes, Michael J. y David D. Reed. "Competition Indices for Mixed Species Northern Hardwoods". Forest Science 37, n.º 5 (1 de noviembre de 1991): 1338–49. http://dx.doi.org/10.1093/forestscience/37.5.1338.
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Abstract Several competition indices are evaluated to determine their relationship with annual diameter growth in mixed species northern hardwood stands in upper Michigan. Indices are evaluated on four species with different shade tolerance. A new index which incorporates factors representing both root and crown competition is formulated and tested. Simple size ratio indices perform as well or better in their correlation with annual diameter growth than growing space, area overlap, and root/crown indices. Hegyi's index and several forms of the new root/crown index show the most consistent performance across study species. For. Sci. 37(5):1338-1349.
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Rumyantsev, Denis Evgenievich, Mariya Alekseevna Lyapicheva, Denis Viktorovich Illarionov y Elizaveta Maksimovna Lebedeva. "The correlation in the dynamics of the growth of European spruce and the dynamics of potato and winter rye yields". Сельское хозяйство, n.º 2 (febrero de 2023): 49–61. http://dx.doi.org/10.7256/2453-8809.2023.2.69664.
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The subject of the study was the meteorological conditionality of fluctuations in the radial growth of European spruce in a single local old-age stand, as well as the conjugacy in fluctuations in the growth indices of European spruce and crop yield indices (winter rye, potatoes) over an 80-year time interval. The study uses time series of yields of winter rye (Secale cereale L.) and potatoes (Solanum tuberosum L.) obtained in the long-term experience of the Timiryazev Agricultural Academy (originally laid down by D.N. Pryanishnikov) for the period 1912-1991. The long chronology of the European spruce (Picea abies (L.) H.Karst.) was obtained on the basis of cuts selected after the wind in the Alekseevskaya grove of the Losiny Ostrov National Park and covers the period 1812-2017. To identify the conjugacy between fluctuations in the indices of radial growth of spruce and meteorological parameters, as well as to identify the conjugacy in fluctuations in the indices of growth of spruce and Correlation analysis was used for the yield indices of winter rye and potatoes. Correlation analysis showed that the formation of spruce growth is positively influenced by elevated temperatures in December and January, negatively affected by elevated temperatures in June in the calendar year of the formation of the annual ring and elevated temperatures in August in the year preceding it. Reliable correlation coefficients of spruce growth indices with monthly precipitation amounts were not found in the ecotope under consideration. Significant correlations were revealed between the dynamics of spruce growth indices and the dynamics of crop yields: the relationship with potato yields in the experiment without lime, without crop rotation and with the application of NPK fertilizers and manure (correlation coefficient 0.22) and the relationship with rye yields in the experiment without lime, without crop rotation and without fertilizers (correlation coefficient 0.23).
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Xie, Min, Jun Luo, Lijun Li, Peng Zhang, Qiang Wu, Mengyuan Li, Haixia Wang y Yongping Zhang. "Correlation between Spring Wheat Physiological Indicators and UAV Digital Image Index in Hetao Irrigation Area". Applied Sciences 14, n.º 6 (8 de marzo de 2024): 2294. http://dx.doi.org/10.3390/app14062294.
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To accurately and non-destructively monitor the growth of spring wheat in the Hetao irrigation area, UAV remote sensing was employed during various fertility stages. Digital image indices from diverse fertilization treatments were calculated and compared with physiological indices to identify the most sensitive digital image indices corresponding to these indices. The study underscored the critical importance of the flowering stage in the growth of spring wheat, thus highlighting the necessity of focusing on this stage. This finding reiterated that the flowering stage was pivotal for spring wheat development in the Hetao Irrigation Area. Several digital image indices, such as GLA, R, G, INT, g, GRVI, MGRVI, RGBVI, EXG, and GRRI, exhibited a high frequency of significant correlations with physiological indices during the four primary reproductive stages of wheat. Consequently, these sensitive digital image indices during the flowering stage can more effectively characterize the physiological indices of spring wheat.
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Nathasri, Winai, Witsaroot Witoontorn y Surachai Chaitusaney. "Substation Expansion Considering Reliability of Various Bus Configurations and Load Growth". Applied Mechanics and Materials 781 (agosto de 2015): 258–61. http://dx.doi.org/10.4028/www.scientific.net/amm.781.258.
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This paper proposes a method for electrical substation expansion by considering reliability indices of various types of bus configuration in electrical substation. The reliability indices LOLF, LOLP, and EENS are evaluated by using Newton-Raphson power flow calculation with minimal cut sets. The yearly load growth, together with power capacity of components (capacity limit of components), and the operation of protective components are also taken into account. Two types of failures, i.e. active failure and passive failure, are considered. Finally, the reliability of all bus configuration types in electrical substation is compared by the reliability indices.
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Filipescu, Cosmin N. y Philip G. Comeau. "Aspen competition affects light and white spruce growth across several boreal sites in western Canada". Canadian Journal of Forest Research 37, n.º 9 (septiembre de 2007): 1701–13. http://dx.doi.org/10.1139/x07-011.
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The effectiveness of competition indices for predicting light transmittance and white spruce ( Picea glauca (Moench) Voss) growth were examined across trembling aspen ( Populus tremuloides Michx.) density gradients using sites from a long-term study of mixedwood growth and development in Alberta and Saskatchewan. Competition indices based on density (number of trees, basal area, and spacing factor), distance-dependent and -independent size ratio (Hegyi’s and Lorimer’s), and crown characteristics (crown volume, surface area, and cross-sectional area) were tested. Transmittance was effectively predicted by crown competition indices followed closely by aspen basal area and size ratio indices. Models of spruce growth indicated better results for stem volume compared with diameter or height. Competition alone accounted for less than 60% of stem growth variation, with basal area and transmittance providing some of the best models. The predictive ability of spruce growth was increased up to 93% by adding initial size as a second explanatory variable. In this respect, initial diameter was superior to initial height, crown volume, and surface area. Relationships between competition, transmittance, and spruce growth were found to differ significantly between geographical locations. These results suggest the need for local development of models relating tree growth to competition.
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Bartha, Jose L., Eva M. Moya y Blas Hervías-Vivancos. "Three-Dimensional Power Doppler Analysis of Cerebral Circulation in Normal and Growth-Restricted Fetuses". Journal of Cerebral Blood Flow & Metabolism 29, n.º 9 (10 de junio de 2009): 1609–18. http://dx.doi.org/10.1038/jcbfm.2009.70.
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The objective of the present study was to evaluate fetal cerebral circulation by using three-dimensional (3D) power Doppler ultrasound in normal and growth-restricted fetuses. A total of 100 normal grown fetuses were compared with other 25 with growth restriction (FGR). Three-dimensional power Doppler ultrasound was used to assess fetal cerebral 3D vascular indices: vascularization index, flow index (FI), and vascularization flow index (VFI). Both FI and VFI correlated positively with gestational age. On average, all the 3D vascular indices were increased in fetuses with FGR. The proportion of fetuses detected as having hemodynamic redistribution was higher when using 3D power Doppler indices than by means of the middle cerebral artery pulsatility index (52% versus 20%, P = 0.002). In conclusion, two of the three indices increased during gestation. All the fetal cerebral 3D vascular indices are increased in fetuses with FGR. In these fetuses, there were more cases suggesting hemodynamic redistribution than expected by conventional Doppler studies.
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BELLO, N. J. "AN INVESTIGATION OF THE AGROCLIMATIC POTENTIAL OF THE FOREST–SAVANNA TRANSITION ZONE OF NIGERIA FOR THE CULTIVATION OF SORGHUM". Experimental Agriculture 33, n.º 2 (abril de 1997): 157–71. http://dx.doi.org/10.1017/s0014479797000057.
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The agroclimatic potential of the forest–savanna transition zone of Nigeria for the cultivation of sorghum (Sorghum bicolor) was investigated. Five phenological stages of the crop formed the basic unit of time for the investigation. Selected agroclimatological thermal and moisture indices were measured daily and processed into ten-day (decadal) averages for the 1993 and 1994 cropping seasons. The thermal indices, temperature and photoperiods were optimal for sorghum growth but, on the basis of the distribution of rainfall and actual water availability in relation to the crop's water consumption, the moisture indices were above optimum. However by relating effective water availability to the indices of moisture adequacy for the growth of the crop, it was found that the agroclimatological moisture indices were optimum during the moisture sensitive stages. A comparison of the vegetative growth and grain yield of sorghum in the study area and elsewhere in the savanna region confirmed the agroclimatic potential of the forest–savanna transition zone for sorghum production.
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Miresan, Vioara, Petru Taran, Camelia Raducu, Aurelia Coroian y Daniel Cocan. "Growth Dynamic and Physiological Status of Calves for Meat Production". Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies 73, n.º 2 (28 de noviembre de 2016): 248. http://dx.doi.org/10.15835/buasvmcn-asb:12222.
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Cattle farming for meat is an activity specific for Romanian zootechnics. Generally, beef cattle farmers acquire claves from the local population. The condition and welfare of calves can be determined based on weight gain and hematological indices. The purpose of our research was to determine the growth dynamic of calves subjected to fattening and to determine the physiological status on growth stages, by hematological investigations. Our research was conducted at the SC ITL AGROCOMPLEX farm – Lechinţa, Bistriţa-Năsăud County. Growth indices (TG – total gain; ADG – average daily gain) were determined based on successive measurements and weightings. The physiological status was determined by hematological analyses (WBC, RBC, HGB, HCT, MCV, MCH, MCHC, leukocytic formula). The experiment lasted for 33 days, 10 calves being studied. The initial mean weight was 53.5±0.513 kg, and the final mean weight was 91.7±0.445 kg, resulting a total gain (TG) of 38.2 kg and an average daily gain (ADG) of 1.158 kg/day. Generally, the obtained hematological values showed a gradual improvement of the physiological status of the calves. Starting with somewhat higher leukocyte values (WBCinitial=10.61±0.329 x 109/L), their level slowly decreased towards the end of the experiment (WBCfinal=8.92±0.204 x 109/L). Regarding other hematological indices, these presented relatively constant values: RBCinitial=9.44±0.151 x 1012/L vs. RBCfinal=9.35±0.114 x 1012/L; HGBinitial= 9.92±0.234 g/dl vs. HGBfinal=9.24±0.155 g/dl; HCTinitial=30.5±0.604% vs. HCTfinal=30.15±0.389%. The obtained results show optimum values for growth dynamic. Also, the hematological indices indicate good maintenance, growth and feeding conditions existent in the farm, the indices improving during the experiment.
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MacDonald, Blake, Dave M. Morris y Peter L. Marshall. "Assessing components of competition indices for young boreal plantations". Canadian Journal of Forest Research 20, n.º 7 (1 de julio de 1990): 1060–68. http://dx.doi.org/10.1139/x90-141.
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Important components of interspecific competition affecting apical and cambial growth in young plantations of black spruce (Piceamariana (Mill.) B.S.P.) and jack pine (Pinusbanksiana Lamb.) in northern Ontario were identified. The relative importance of competition, initial seedling status, and some soil factors was also assessed. Measures of perennial competition were calculated using hemispherical photographs, stand maps, and mensurational data from 360 seedling-centred plots (1.4 m radius) for each of the two species. Fractal geometry was used to quantify the textures of the competing canopies. Reliable competition indices should include horizontal and vertical dimensions and express the amount of competition relative to the size of the seedling. The total canopy fraction on the photographs and some simple field measurements of competition correlated significantly with seedling growth. Complex expressions of competition were unjustified, and measures of dispersion and canopy texture correlated weakly with growth. The consistently good correlations between growth and some components of competition revealed that an index applicable to all species, stock types, and growth responses could be developed.
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Wang, Haoyue, Wei Qi, Yuefeng Guo y Yajie Xu. "Effects of stumping on fine root architecture, growth, and physiology of Hippophae rhamnoides". PeerJ 11 (9 de marzo de 2023): e14978. http://dx.doi.org/10.7717/peerj.14978.
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Background Fine roots are vital to a plant’s ability to absorb water and nutrients. Stumping is a practice that may encourage fine root growth and the rapid recovery of decaying Hippophae rhamnoides plants. However, the effect of stumping on the fine roots and physiological indices is still unknown. The differential indices between stumped forests and non-stumped forests must also be defined. Methods We recorded the changes in the fine roots of structure H. rhamnoides one year after stumping. Using single factor analysis of variance and general linear models we comprehensively analyzed the number of root tips and the plant’s growth and physiological indices in response to stumping. Partial least squares discriminant analysis (PLS-DA) was used to compare fine root growth and physiological indices with and without stumping in order to identify the differential indices. Results The proportion of root tips in the vertical layers at 30–40 cm and 40–50 cm and in the horizontal layers at 60–80 cm and 80–100 cm, increased after stumping by 1.85%, 2.60%, 1.96% and 4.32%, respectively. In the 0–50 cm soil layer, the fine root dry weight rose by 27.6% compared with the control, which was not significant. However, other indices were significantly different from the control. The proportions in the growth indices in the 30–40 cm and 40–50 cm layers increased after stumping. Stumping had a significant, negative effect on proline and malondialdehyde content, which dropped by 40.95% and 55.32%, respectively, indicating that the harms caused by these two chemicals was alleviated. Stumping had a significant positive effect on root activity and soluble sugar contents, which increased by 68.58% and 36.87%, respectively, and improved the growing ability of fine roots. PLS-DA revealed that malondialdehyde, soluble sugars, root density, and the number of root tips ranked from having the least to greatest effect on the classification of stumping and no-stumping. Conclusions The process of stumping may promote fine roots growth in H. rhamnoides, and is favorable for their longitudinal development. The fine root growing indices of H. rhamnoides responded positively to this process. Stumping promotes root activity and the creation of soluble sugar to maintain the growth and development of fine roots. It also inhibits the negative effects of proline and malondialdehyde on fine roots. Our study showed that the differential physiological indices were more important for classification than the differential growing indices.
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De Freitas Melo, Cynthia, Marina Braga Teófilo, Gabriel Huet Borges de Arruda, Elisa Kern de Castro, Normanda Araújo de Morais y Icaro Moreira Costa. "Stress and Post-traumatic Growth of people with cancer: identification of associated factors". Psicooncología 21, n.º 1 (11 de abril de 2024): 111–24. http://dx.doi.org/10.5209/psic.94817.
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Objectives: Evaluate indicators and identify associated factors of post-traumatic stress disorder (PTSD) and post-traumatic growth (PTG) in individuals undergoing oncological treatment. Method: Quantitative, cross-sectional, analytical survey design with a non-probabilistic sample of 74 participants. Six instruments measuring PTSD, PTG, spiritual well-being, illness perception, and social support were employed. Data were analyzed using descriptive and inferential statistics in the Statistical Package for Social Science (SPSS). Results: It was evidenced that 21.60% of patients presented clinical indices of PTSD, and 85.12% showed a high index for PTG. High satisfaction indices were also observed for social support (86.48%), spiritual well-being (95.94%), and in identifying cancer as a potential threat to life (71.57%). Females, unmarried individuals, those inactive or unemployed, and those receiving public health support exhibited higher PTG indices. Women exhibit higher PTSD indices than men. Negative correlations were found between PTSD and spiritual well-being, and positive correlations with illness perception. Illness perception emerged as the variable with the greatest predictive power for PTSD indices. Conclusions: It is concluded that the threatening perception of the illness is a predictor of PTSD, highlighting it as a risk factor that requires attention in health prevention plans.
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Peña-Gallardo, Marina, Sergio Vicente-Serrano, J. Camarero, Antonio Gazol, Raúl Sánchez-Salguero, Fernando Domínguez-Castro, Ahmed El Kenawy et al. "Drought Sensitiveness on Forest Growth in Peninsular Spain and the Balearic Islands". Forests 9, n.º 9 (30 de agosto de 2018): 524. http://dx.doi.org/10.3390/f9090524.
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Drought is one of the key natural hazards impacting net primary production and tree growth in forest ecosystems. Nonetheless, tree species show different responses to drought events, which make it difficult to adopt fixed tools for monitoring drought impacts under contrasting environmental and climatic conditions. In this study, we assess the response of forest growth and a satellite proxy of the net primary production (NPP) to drought in peninsular Spain and the Balearic Islands, a region characterized by complex climatological, topographical, and environmental characteristics. Herein, we employed three different indicators based on in situ measurements and satellite image-derived vegetation information (i.e., tree-ring width, maximum annual greenness, and an indicator of NPP). We used seven different climate drought indices to assess drought impacts on the tree variables analyzed. The selected drought indices include four versions of the Palmer Drought Severity Index (PDSI, Palmer Hydrological Drought Index (PHDI), Z-index, and Palmer Modified Drought Index (PMDI)) and three multi-scalar indices (Standardized Precipitation Evapotranspiration Index (SPEI), Standardized Precipitation Index (SPI), and Standardized Precipitation Drought Index (SPDI)). Our results suggest that—irrespective of drought index and tree species—tree-ring width shows a stronger response to interannual variability of drought, compared to the greenness and the NPP. In comparison to other drought indices (e.g., PDSI), and our results demonstrate that multi-scalar drought indices (e.g., SPI, SPEI) are more advantageous in monitoring drought impacts on tree-ring growth, maximum greenness, and NPP. This finding suggests that multi-scalar indices are more appropriate for monitoring and modelling forest drought in peninsular Spain and the Balearic Islands.
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LeBlanc, David C. y Jeffrey R. Foster. "Predicting effects of global warming on growth and mortality of upland oak species in the midwestern United States: a physiologically based dendroecological approach". Canadian Journal of Forest Research 22, n.º 11 (1 de noviembre de 1992): 1739–52. http://dx.doi.org/10.1139/x92-228.
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This study combined an ecophysiological model and dendroecological analyses to evaluate potential effects of global warming on the physiology, growth, and mortality of white oak (Quercusalba L.) and black oak (Quercusvelutina Lam.) in the Ohio River region. The model integrated data for ecophysiology of oak species, site attributes, and daily temperature and precipitation to model nonlinear responses of stomatal conductance (gs), net photosynthesis (Pnet), and woody respiration (Rw) to variations in temperature and soil water content. Relationships between modeled physiological response indices and actual white and black oak annual radial growth indices were evaluated by regression analyses, using growth and weather data for the period 1900–1987 for seven upland oak–hickory forests. Modeled physiological response indices explained 40–60% of variation in radial growth indices. To evaluate the effects of global warming, daily temperature values for the period 1900–1987 were increased by 2 or 5 °C, without changing precipitation values, and physiological response indices were computed. Model indices generated in warming simulations were entered into dendroclimatic regression models calibrated under conditions without any warming to predict radial growth under warming scenarios. Under the warming scenarios, OAKWBAL predicted a substantial increase in growing season Rw, but little change in growing season Pnet. Warming merely shifted the period of near-maximal Pnet earlier in the growing season, without changing its duration. However, this result was somewhat dependent upon the ability of leaf-out phenology to track changes in temperature regime. The net effect of increased Rw, with little change in Pnet, was a reduction in radial growth and a higher frequency of years with climatic conditions stressful to oaks on upland sites. A historical association between severe drought and increased incidence of oak growth decline and mortality indicated that global warming could increase the incidence of decline and mortality in oak populations on upland sites similar to those in this study.