Nitrogen (N) fertilizer rate is important for high yield and good quality of potato tubers. In this dissertation, I seek to study the response of different potato cultivars under different N fertilizer rates and how that can impact tuber quality, examine the performance of active optical sensors in improving a potato yield prediction algorithm, and evaluate the ability of active optical sensors (GreenSeeker (GS) and Crop Circle (CC)) to optimize a N recommendation algorithm that can be used by potato growers in Maine. This research was conducted at 11 sites over a period of two years (2018–2019) in Aroostook County, Maine; all sites depended on a rainfed system. Three potato cultivars, Russet Burbank, Superior, and Shepody, were planted under six rates of N (0-280 kg ha-1), ammonium sulfate and ammonium nitrate, and were applied in a randomized complete block design (RCBD) with four replications. Active optical sensor readings (normalized difference vegetation index (NDVI)) were collected weekly after the fourth leaf stage began. The coefficient of determination (R2) between soil organic matter (OM) content and total tuber yield for all sites combined was 0.78**. Sites with ≥ 30 g kg-1 of soil OM produced higher total tuber yield, marketable yield, and tuber weight per plant (39.45%, 45.22%, and 54.94%, respectively) than sites with ≤ 30 g kg-1 of OM. Specific gravity increased by 0.18% in the sites with ≥ 30 g kg-1 of OM. The total tuber yield for the three cultivars was maximized at 168 kg N ha-1. Vegetation indices measurements obtained at stages of 16 or 20 fully expanded leaves were significantly correlated with tuber yield, which can be used in the yield prediction model. Sensor measurements obtained at the 20th leaf stage were significantly correlated with tuber yield, with the exponential model showing the best fit for the regression curve. The recommended N rate calculated based on in-season sensor readings was reduced by approximately 12–14% compared to the total N rate that growers currently apply based on the conventional approach.
يكشف هذا المقال عن مشكلة الصفات ذات المكون الكمي والتي تعتبر واحدة من اقوى الموارد المكونة للكلمات التعبيرية والتقويمية و يتم تحليل التركيبات الدلالية ذات الاوجه المتعددة التي تنشا من عملية توظيف الصفات المشتقة بمساعدة اللواحق والتي تدل على الاتجاه العام للغات السلافية وذلك لتطوير الدلالات العاطفية والتقييمية في الكلمات ذات معنى الميزة او الخاصية يتم تقديم تعريف انماط تكوين المعاني الضمنية في دلالات
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Enzyme activity were studied in the sera of children with leukemia than healthy children, where 31 cases were studied, including 21 cases of patients with acute lymphatic leukemia
Infection of the gastric mucosa with Helicobacter pylori is strongly associated with chronic gastritis, peptic ulcer and gastric cancer. Helicobacter pylori virulence factors include a variety of proteins that are involved in its pathogenesis, such as VacA and CagA. Another group of virulence factors is clearly important for colonization of H.pylori in the gastric mucosa. These include urease, motility factors (flagellin), and Superoxide dismutase (SOD). Because of this organism's microaerophilic nature and the increased levels of reactive oxygen in the infected host, we expect that other factors involved in the response to oxidative stress are likely to be required for virulence. Superoxide dismutase is a near
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This study was conducted to investigate thyroid function and Anti-Müllerian hormone (AMH) in (Chronic kidney disease) CKD patients by evaluating their levels in CKD patients, 50 patients were diagnosed to have CKD stage-5, their ages ranged between 20-50 years (25 males and 25 females) who attended the Nephrology and Transplant Center in Medical City of Baghdad- Iraq, they were recruited from April 2018 to July 2018 and were enrolled into the study. The control group consisted of 20 healthy individuals, their ages ranged between 20-48 years (10 males and 10 females). The study showed non-significant (p>0.05) increase in AMH level in CKD patients compared to the control group. On the other hand, TSH was recorded a highly significant (
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The present study aims at assessing the effects of chronic kidney disease (CKD) on thyroid hormone and leptin by evaluating the level of: leptin hormone along with thyroid hormone in CKD patients. The study has been conducted on 70 subjects, 50 patients with an age range between 20-50 years (25 males and 25 females) who were diagnosed to have CKD stage-5, and 20 normal controls whose ages ranged between 20-48 years (10 males and 10 females), who attended the Nephrology and Transplant Center in Medical City of Baghdad- Iraq from April 2018 to July 2018. The study showed a highly significant (P<0.01) increase in TSH level in CKD patients in comparison with controls. While T3 and T4 levels observed highly significant decrea
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