scholarly journals (347) Identifying Common Reflectance Properties in Diverse Ornamental Species to Nondestructively Determine Nitrogen Status

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1060C-1060
Author(s):  
Jonathan M. Frantz ◽  
Dharmalingam S. Pitchay ◽  
Glen Ritchie ◽  
Heping Zhu

Nitrogen (N) is often supplied to plants in excess to minimize the possibility of encountering N deficiency that would reduce the plant quality due to leaf chlorosis and necrosis. This is not only costly, but it can reduce the quality of plants, predispose the plants to biotic stress such as Botrytisgray mold, and extend the production cycle. Several tools can be used to identify N deficiency in plants, and most are based on chlorophyll reflectance or transmittance. While sensitive when plants are experiencing N deficiency, spectral signals can saturate in an ample N supply and make it difficult to discern sufficient and supra-optimal N nondestructively. Three diverse ornamental species (begonia, Begoniacea×tuberhybrida; butterflybush, Buddlejadavidii; and geranium, Pelargonium×hortorum) were grown with a broad range of N supplied (1.8 to 58 mm) in three separate studies that resulted in a range of 1.8% to 6% tissue N concentration. Using a spectroradiometer, we measured reflectance from the whole plants twice over a period of 3 weeks. A first-derivative analysis of the data identified six wavebands that were strongly correlated to both begonia and butterflybush tissue N concentration (r2 ∼ 0.9), and two of these also correlated well to geranium N concentration. These wavebands did not correlate to chlorophyll peak absorbance, but rather blue, green, red, and far-red “edges” of known plant pigments. These wavebands hold promise for use as a nondestructive indicator of N status over a much broader range of tissue N concentration than current sensors can reliably predict.

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 937
Author(s):  
Francisco Javier López-Moreno ◽  
Santiago Atero-Calvo ◽  
Eloy Navarro-León ◽  
Begoña Blasco ◽  
Teresa Soriano ◽  
...  

Green asparagus (Asparagus officinalis L.) is a widely grown and consumed crop which provides high-level nutritional interest. In recent years, the decline syndrome in asparagus plantations has been rapidly augmenting. This syndrome causes the early death of whole plants, also negatively affecting the new replanting. Decline causes notable economic losses in the sector. The objective of this work was to verify the effect of different treatments against asparagus decline syndrome on the physiological parameters and nutritional quality of the spears. To meet the objective, four different treatments were applied to asparagus plots strongly affected by decline syndrome: (T1) untreated control soil, (T2) biofumigation with Brassica pellets, (T3) biofumigation with chicken manure pellets, and (T4) disinfestation of the soil with Dazomet. The cumulative yield and physiological and quality parameters of green asparagus spears were studied. Thus, malondialdehyde (MDA), photosynthetic pigments, glutathione (GSH), ascorbate (AsA), total phenols, flavonoids, anthocyanin, antioxidant test, mineral nutrients, and the amino acid profile were measured on asparagus spears. The results showed that the Brassica pellets and Dazomet treatments were the most effective against the damage caused by the decline syndrome. However, it would be necessary to monitor the evolution in the following years.


Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 261
Author(s):  
María Teresa Ariza ◽  
Luis Miranda ◽  
José Antonio Gómez-Mora ◽  
Juan Jesús Medina ◽  
David Lozano ◽  
...  

Strawberry (Fragaria×ananassa Duch.) production requires the input of large amounts of water provided by irrigation during the entire production cycle. However, water availability is shrinking in many important strawberry cropping areas, such as Huelva (in Europe), compromising the environmental sustainability and economic viability of strawberry production. Besides technical approaches, water-saving strategies are necessary for improving strawberry water productivity such as the use of low water-consumptive cultivars with high productivity or cultivars allowing deficit irrigation (DI) strategies. A two-year field experiment was conducted to compare the physiological and agronomical response of six commercial strawberry cultivars (‘Sabrina’, ‘Fortuna’, ‘Splendor’, ‘Primoris’, ‘Rabida’ and ‘Rociera’) to six different water treatments ranging from 65% to 140% of estimated ‘Sabrina’ evapotranspiration (ETcSab; ~224–510 mm year−1). Cultivars differed substantially in yield and water consumption linked to their biomass partitioning into reproductive/ vegetative organs, determining different yield efficiency (YE). Their water needs (IN) conditioned their response to different water supplies, involving significant yield losses in DI treatments (<20% IN) but not decreasing fruit quality. The highly-consumptive and productive ‘Rabida’ and ‘Rociera’, reduced yields by DI (<40%) but were still profitable; the low-water-consumptive but still productive ‘Fortuna’, ‘Splendor’ and ‘Primoris’ represent significant water-savings (<20%) in strawberry cultivation.


2020 ◽  
Vol 105 (7) ◽  
pp. 2430-2441
Author(s):  
Åse Bjorvatn Sævik ◽  
Anna-Karin Åkerman ◽  
Paal Methlie ◽  
Marcus Quinkler ◽  
Anders Palmstrøm Jørgensen ◽  
...  

Abstract Context Contrary to current dogma, growing evidence suggests that some patients with autoimmune Addison disease (AAD) produce corticosteroids even years after diagnosis. Objective To determine frequencies and clinical features of residual corticosteroid production in patients with AAD. Design Two-staged, cross-sectional clinical study in 17 centers (Norway, Sweden, and Germany). Residual glucocorticoid (GC) production was defined as quantifiable serum cortisol and 11-deoxycortisol and residual mineralocorticoid (MC) production as quantifiable serum aldosterone and corticosterone after &gt; 18 hours of medication fasting. Corticosteroids were analyzed by liquid chromatography–tandem mass spectrometry. Clinical variables included frequency of adrenal crises and quality of life. Peak cortisol response was evaluated by a standard 250 µg cosyntropin test. Results Fifty-eight (30.2%) of 192 patients had residual GC production, more common in men (n = 33; P &lt; 0.002) and in shorter disease duration (median 6 [0-44] vs 13 [0-53] years; P &lt; 0.001). Residual MC production was found in 26 (13.5%) patients and associated with shorter disease duration (median 5.5 [0.5-26.0] vs 13 [0-53] years; P &lt; 0.004), lower fludrocortisone replacement dosage (median 0.075 [0.050-0.120] vs 0.100 [0.028-0.300] mg; P &lt; 0.005), and higher plasma renin concentration (median 179 [22-915] vs 47.5 [0.6-658.0] mU/L; P &lt; 0.001). There was no significant association between residual production and frequency of adrenal crises or quality of life. None had a normal cosyntropin response, but peak cortisol strongly correlated with unstimulated cortisol (r = 0.989; P &lt; 0.001) and plasma adrenocorticotropic hormone (ACTH; r = –0.487; P &lt; 0.001). Conclusion In established AAD, one-third of the patients still produce GCs even decades after diagnosis. Residual production is more common in men and in patients with shorter disease duration but is not associated with adrenal crises or quality of life.


EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
D Tachmatzidis ◽  
D Filos ◽  
I Chouvarda ◽  
A Tsarouchas ◽  
D Mouselimis ◽  
...  

Abstract Background A manually beat-to-beat P-wave analysis has previously revealed the existence of multiple P-wave morphologies in patients with paroxysmal Atrial Fibrillation (AF) while on sinus rhythm, distinguishing them from healthy, AF free patients. Purpose The aim of this study was to investigate the effectiveness of an Automated Beat Exclusion algorithm (ABE) that excludes noisy or ectopic beats, replacing manual beat evaluation during beat-to-beat P-wave analysis, by assessing its effect on inter-rater variability and reproducibility. Methods Beat-to-beat P-wave morphology analysis was performed on 34 ten-minute ECG recordings of patients with a history of AF. Each recording was analyzed independently by two clinical experts for a total of four analysis runs; once with ABE and once again with the manual exclusion of ineligible beats. The inter-rater variability and reproducibility of the analysis with and without ABE were assessed by comparing the agreement of analysis runs with respect to secondary morphology detection, primary morphology ECG template and the percentage of both, as these aspects have been previously used to discriminate PAF patients from controls. Results Comparing ABE to manual exclusion in detecting secondary P-wave morphologies displayed substantial (Cohen"s k = 0.69) to almost perfect (k = 0.82) agreement. Area difference among auto and manually calculated main morphology templates was in every case &lt;5% (p &lt; 0.01) and the correlation coefficient was &gt;0.99 (p &lt; 0.01). Finally, the percentages of beats classified to the primary or secondary morphology per recording by each analysis were strongly correlated, for both main and secondary P-wave morphologies, ranging from ρ=0.756 to ρ=0.940 (picture) Conclusion The use of the ABE algorithm does not diminish inter-rater variability and reproducibility of the analysis. The primary and secondary P-wave morphologies produced by all analyses were similar, both in terms of their template and their frequency. Based on the results of this study, the ABE algorithm incorporated in the beat-to-beat P-wave morphology analysis drastically reduces operator workload without influencing the quality of the analysis. Abstract Figure.


2009 ◽  
Vol 38 (5) ◽  
pp. 857-862
Author(s):  
Fernando Guilherme Perazzo Costa ◽  
Janaine Sena da Costa ◽  
Cláudia de Castro Goulart ◽  
Denise Fontana Figueiredo-Lima ◽  
Raul da Cunha Lima Neto ◽  
...  

This study was carried out to evaluate the energy levels in the diet to obtain better performance rates and quality of eggs from laying hens in the second production cycle. One hundred and eighty Bovans Goldline laying hens with 62 weeks of age were used during four 28-day periods. A completely randomized experimental design was used with four metabolizable energy levels (2,650, 2,725, 2,800, 2,875 and 2,950 kcal/kg), each with six replicates of six birds. The energy level of diet did not affect the weight of the egg, yolk, albumen and eggshell, the percentages of yolk, albumen and eggshell, yolk color and egg specific gravity. Feed intake, egg production, egg mass and feed conversion per egg mass and per dozen eggs increased significantly with increasing levels of metabolizable energy. Feed intake decreased linearly as the energy level in the diet increased. The metabolizable energy levels showed a quadratic effect on egg production, egg mass and feed conversion per egg mass and per dozen eggs. The metabolizable energy level of 2,830 kcal/kg was the most appropriate to promote better performance and quality of eggs from laying hens in the second production cycle.


2018 ◽  
Vol 19 (10) ◽  
pp. 2907 ◽  
Author(s):  
Miyako Kurihara-Shimomura ◽  
Tomonori Sasahira ◽  
Chie Nakashima ◽  
Hiroki Kuniyasu ◽  
Hiroyuki Shimomura ◽  
...  

Head and neck cancers, including oral squamous cell carcinoma (OSCC), are the sixth most common malignancies worldwide. OSCC frequently leads to oral dysfunction, which worsens a patient’s quality of life. Moreover, its prognosis remains poor. Unlike normal cells, tumor cells preferentially metabolize glucose by aerobic glycolysis. Pyruvate kinase (PK) catalyzes the final step in glycolysis, and the transition from PKM1 to PKM2 is observed in many cancer cells. However, little is known about PKM expression and function in OSCC. In this study, we investigated the expression of PKM in OSCC specimens and performed a functional analysis of human OSCC cells. We found that the PKM2/PKM1 ratio was higher in OSCC cells than in adjacent normal mucosal cells and in samples obtained from dysplasia patients. Furthermore, PKM2 expression was strongly correlated with OSCC tumor progression on immunohistochemistry. PKM2 expression was higher during cell growth, invasion, and apoptosis in HSC3 cells, which show a high energy flow and whose metabolism depends on aerobic glycolysis and oxidative phosphorylation. PKM2 expression was also associated with the production of reactive oxygen species (ROS) and integration of glutamine into lactate. Our results suggested that PKM2 has a variety of tumor progressive functions in OSCC cells.


Author(s):  
Jennifer Raybin ◽  
Verna Hendricks-Ferguson ◽  
Paul Cook ◽  
Catherine Jankowski

Symptom distress and decreased quality of life (QOL) among children with cancer are well documented. Research is emerging on the child’s voice in QOL-symptom reports, but existing QOL questionnaires are burdensome and objective biologic markers are lacking. We examined children’s symptoms and QOL from parent and child perspectives and compared the results to one biologic marker (body posture). A cross-sectional secondary analysis of prospective data from children receiving creative arts therapy explored potential associations among demographics with and between QOL measures (PedsQL, Faces Scale, posture). Children (n = 98) ranged in age from 3-17 years (M = 7.8) and were in the first year of cancer treatment. No significant associations were found among the child’s sex, race/ethnicity, socioeconomic status (SES), or distance from hospital and total PedsQL. Older age was associated with worse total PedsQL, pain, nausea, worry, and posture (all ps < .05). Greater worry (β = 0.51) and worse posture (β = 0.41) were the QOL variables most strongly correlated with older age. Poorer posture was associated with worse child PedsQL (total score, nausea, treatment anxiety, cognitive) and parent PedsQL (pain, nausea). Worse scores on the Faces Scale, PedsQL, and posture were all correlated (rs = .21 - .39, all ps < .05). Interventions to improve QOL could target nausea, worry, and older patients. Accuracy and interpretation of symptom distress in children is problematic. The Faces Scale and posture may be suitable, readily obtained measures of QOL in pediatric oncology that hold promise.


1998 ◽  
Vol 123 (4) ◽  
pp. 563-568 ◽  
Author(s):  
Anil P. Ranwala ◽  
William B. Miller

Experiments were conducted to evaluate storage temperature, storage irradiance and prestorage foliar sprays of gibberellin, cytokinin or both on postharvest quality of Oriental hybrid lilies (Lilium sp. `Stargazer'). Cold storage of puffy bud stage plants at 4, 7, or 10 °C in dark for 2 weeks induced leaf chlorosis within 4 days in a simulated consumer environment, and resulted in 60% leaf chlorosis and 40% leaf abscission by 20 days. Cold storage also reduced the duration to flower bud opening (days from the end of cold storage till the last flower bud opened), inflorescence and flower longevity, and increased flower bud abortion. Storage at 1 °C resulted in severe leaf injury and 100% bud abortion. Providing light up to 40 μmol·m-2·s-1 during cold storage at 4 °C significantly delayed leaf chlorosis and abscission and increased the duration of flower bud opening, inflorescence and flower longevity, and reduced bud abortion. Application of hormone sprays before cold storage affected leaf and flower quality. ProVide (100 mg·L-1 GA4+7) and Promalin (100 mg·L-1 each GA4+7 and benzyladenine (BA)) effectively prevented leaf chlorosis and abscission at 4 °C while ProGibb (100 mg·L-1 GA3) and ABG-3062 (100 mg·L-1 BA) did not. Accel (10 mg·L-1 GA4+7 and 100 mg·L-1 BA) showed intermediate effects on leaf chlorosis. Flower longevity was increased and bud abortion was prevented by all hormone formulations except ProGibb. The combination of light (40 μmol·m-2·s-1) and Promalin (100 mg·L-1 each GA4+7 and BA) completely prevented cold storage induced leaf chlorosis and abscission.


2020 ◽  
Author(s):  
Marta Kolczynska ◽  
Paul - Christian Bürkner

Social scientists can choose from among multiple quality of governance indicators which use different conceptualizations of governance and its components, rely on different data sources, and employ different aggregation and scaling techniques. Despite all differences, these indicators are commonly found to be strongly correlated, which makes the choice of indicator for a given analysis seem inconsequential. We demonstrate that the correlations between governance indicators are indeed high when comparing across countries or using pooled country-year data sets, but are surprisingly low -- sometimes even negative -- within countries. Given the increased interest of researchers in longitudinal analyses with country time series, low agreement between country time trends in the quality of governance is concerning. We illustrate the problem with an analysis of the effect of rule of law on support for democracy, which leads to opposite conclusions depending on which measure of rule of law is used.


2016 ◽  
Vol 3 ◽  
pp. 48
Author(s):  
Carlos Rodríguez ◽  
Juan A. Quiñones ◽  
Rodrigo Arias

The trial was conducted at the Centro de Producción Agrícola of ICfA in Cuyuta, Escuintla-Guatemala in order to generate information on the yield and quality of edible mulberry (Morus sp.) roughage treatments consisted of three harvest frequencies (6; 9 and 12 weeks and three fertilization levels of nitrogen (0.40 and 80 kg/ha). A complete randomized block experimental design, with a factorial arrangement (3x3) was used. The cutting height was 0.3 m above the ground level with two sequencies: from August 2nd to September 13 th and from September 13th to December 6th, 1990. In both cases, the 12 week frequency cutting and 80 kg of N were superior to the others (P<=0.01), yielding 6.87 and 6.15 t/ha of dry matter respectively. The yields at 9 weeks were statistically higher than those at 6 weeks. The highest protein percentage of the whole plant, leaves and stalks were produced at 6 weeks. The dry matter digestibility values in vitro showed little variability among treatments, with averages for whole plants, leaves and stalks of 65, 91 and 41 %, respectively. The preceeding data suggests that the mulberry has an excellent potential as a balanced supplement (protein and energy) for dual purpose cattle on the Southern coast of Guatemala.


Sign in / Sign up

Export Citation Format

Share Document