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New Delhi, India

Harrell D.L.,Louisiana State University | Tubana B.S.,Louisiana State University | Walker T.W.,Mississippi State University | Phillips S.B.,Cross Roads
Agronomy Journal

Normalized difference vegetation index (NDVI) measurements have the potential to improve mid-season N crop management decisions in rice (Oryza sativa L.). The objectives of this study were to determine the optimum sensing timing and establish a yield prediction model using NDVI measurements acquired with the Green Seeker sensor. Weekly sensor readings were collected over a 5-wk period from multi-rate N fertilization trials established at six different locations from 2008 to 2010. Categorizing sensing timing by growth stage demonstrated that late sensing timings beyond panicle differentiation (PD) were impractical and reduced yield potential estimation as opposed to panicle initiation (PI) and PD timings. Regression analysis produced two viable yield potential prediction equations at PI (r 2 = 0.36) and PD (r 2 = 0.42). When sensor timings were categorized by cumulative growing degree days (GDD), 1301 to 1500 and >2100 GDD groupings (r 2 = 0.28 and 0.37, respectively) were found to be inferior yield predictors as compared with 1501 to 1700 and 1701 to 1900 GDD groupings (r 2 = 0.41 for both). In almost all instances, normalization of NDVI data using days from seeding (DFS; NDVI/DFS) or GDD (NDVI/GDD) did not improve yield potential prediction as compared with NDVI alone. Yield potential, response index, and N response to fertilization are the three major components needed to produce a working algorithm capable of predicting mid-season N fertilization needs in rice. The four yield prediction models gleaned from this study provide the yield potential component for this algorithm. Multiple yield prediction models give crop managers freedom to select a model based on either physical growth stage or by accumulated GDD units. © 2011 by the American Society of Agronomy. Source

Otwell J.L.,Auburn University | Phillippe H.M.,Cross Roads | Dixon K.S.,Huntsville Hospital
American Journal of Health-System Pharmacy

Purpose. The efficacy and safety of i.v. alteplase up to 4.5 hours after acute ischemic stroke (AIS) onset were evaluated. Summary. Stroke is the leading cause of disability in the elderly, and i.v. alteplase (recombinant tissue plasminogen activator) is the only Food and Drug Administration (FDA)-approved thrombolytic agent for the treatment of AIS. Alteplase has been shown to decrease the percentage of patients disabled by a stroke. Until recently, the use of alteplase was only recommended within 3 hours of the onset of AIS symptoms. However, two clinical trials published in 2008 demonstrated that therapy with i.v. alteplase remains safe and effective when given 3-4.5 hours after AIS onset. Although FDA has not yet approved expanding the time interval to 4.5 hours for treatment with i.v. alteplase, the American Stroke Association recently published a statement recommending administration of alteplase in eligible patients 3-4.5 hours after symptom onset. There is clinical evidence supporting the safety and efficacy of i.v. alteplase administration to eligible patients who present within 4.5 hours of AIS symptom onset. Treatment with alteplase decreases the likelihood of disability from an AIS and is not associated with an increased rate of mortality. Expanding the time window for treatment with alteplase would likely increase the percentage of AIS patients who are able to receive alteplase and thus ultimately decrease the percentage of those left disabled from an AIS. Conclusion. Evidence supports the safety and efficacy of i.v. alteplase administration to eligible patients within 4.5 hours of AIS symptom onset. Copyright © 2010, American Society of Health-System Pharmacists, Inc. All rights reserved. Source

Trivedi P.D.,K B Institute of Pharmaceutical Education and Research | Maheshwari D.G.,Cross Roads
International Journal of ChemTech Research

A new absorption ratio method was developed and validated for the determination of Esomeprazole and Domperidone in capsules. The method involved Q-absorption analysis based on the measurement of absorbance at two wavelengths, i.e λmax of Esomeprazole (301 nm) and Iso-absorptive point of both drugs (290 nm). Beer's law was obeyed in the concentration range between 1-11μg for both Esomeprazole and Domperidone. The results of analysis have been validated statistically and by recovery studies. The method was found to be simple, precise, reproducible, less time consuming and economical. Hence it is more suitable for routine analysis of these drugs in combined dosage forms. Source

Thomason W.E.,Virginia Polytechnic Institute and State University | Phillips S.B.,Cross Roads | Davis P.H.,Virginia Cooperative Extension | Warren J.G.,Oklahoma State University | And 2 more authors.
Precision Agriculture

Variable rate nitrogen (N) application based on in-season remote sensing can potentially improve wheat (Triticum aestivum L.) N management and N use efficiency (NUE). The goal of this study was to evaluate the potential of improving in-season soft red winter wheat (SRWW) variable rate N recommendations based on crop canopy reflectance. Small-plot N rate response calibration studies guided development of the Virginia Wheat Algorithm (VWA) for grain yield prediction and variable rate N fertilizer rate determination for SRWW. Large plot, replicated validation studies conducted for 15 site-years included an N-rich strip installed at growth stage (GS) 25 and various treatments at GS 30; four or five fixed-rate treatments applied to evaluate site N response, a variable rate based on the VWA applied using a GreenSeeker ® RT 200 system and a "standard" fixed rate based on GS 30 wheat tissue N concentration. All sites responded positively to GS 30 N application. When data from one site were excluded, rates were 8 and 3 kg ha -1 below the economically optimal N rate (EONR) for the VWA and standard methods, respectively. Based on these data, the GreenSeeker ® RT 200 system employing the VWA was equivalent to the current standard method and offers real-time rate prescriptions with less labor and less delay than the current tissue N concentration sufficiency standard. © 2010 Springer Science+Business Media, LLC. Source

A modified technique for externalizing the haptics in the Agarwal method of glued intrascleral fixation of a posterior chamber intraocular lens (IOL) is described. This technique eliminates the role of an assistant in holding the haptic during the entire surgical maneuver and subsequent complications associated with inappropriate handling of the haptic. The technique was used in 45 cases and was reproducible in all cases with no intraoperative complications. This technique is an attempt to make the process of haptic externalization, considered the most technically demanding part of the surgery, more easy and feasible. Financial Disclosure: The author has no financial or proprietary interest in any material or method mentioned. © 2013 ASCRS and ESCRS. Source

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