Effects of Optical Sensing and Variable Rate Technology on Nitrogen Fertilizer Use, Lint Yields, and Profitability in Cotton Production

Nitrogen (N) fertilizer is expensive and can be harmful to the environment. Precision agriculture (PA) has the capability to reduce the amount of excess N from crop production released into the environment, increase net returns to the grower, and reduce the risk of profit loss due to spatial and temporal variability. The objectives of this study were to evaluate the profitability, risk management potential, and N use efficiency of using real-time optical sensing with variable-rate technologies (VRT) to manage spatial variability in cotton production. Data collected from 29 field trials in Tennessee, Louisiana, Mississippi, and Missouri from 2011 to 2014 included lint yields harvested and N rates calculated from three N rate management strategies. The first N treatment was the existing farmer practice (FP), the second was a VRT treatment using optical sensing technology Greenseeker™, and the third was a VRT treatment using Greenseeker™ and yield monitor information. The two PA strategies were compared to the existing farmer practice. In addition, soil properties and weather were examined to determine their effects on lint yields, net returns, N rates, and N use efficiency. Three methods used in this study each include an analysis of lint yields, N rates, net returns, and N use efficiency. The first model was an analysis of variance (ANOVA) to identify treatment mean differences. The second model was an ANOVA that measured soil and weather effects on mean differences between technology and FP. The third model was a logistic analysis to test for risk of a loss using VRT. Results indicated differences in technology net returns versus the FP and no differences between VRT and FP in yields, N rates, or N use efficiency. Warmer temperatures were negatively associated and a greater percentage of organic matter had positive associations with VRT net returns and N use efficiency relative to FP. Profit risk management benefits were identified using Greenseeker™ versus the FP. Results can be used by Extension offices and cotton farmers in Tennessee, Mississippi, Louisiana, and Missouri to determine if adopting optical sensing and VRT would be beneficial to their operations

Ruminations on Contract Drafting: Best Practices in Drafting Offshore and Onshore Form Agreements

The purpose of this paper is to address a number of recommended practices for preparation of agreements typically utilized in the energy industry. Specifically, this paper is meant to assist attorneys in preparing and drafting a forms library of agreements for a client in the oil and gas business. For example, imagine that a new client seeking to enter into the oil and gas business asks the attorney to prepare all of the standard documents that will be necessary in these transactions. How and where does one begin

Characteristics of temporal fluctuations in the hyperpolarized state of the cortical slow oscillation

We present evidence for the hypothesis that transitions between the low- and high-firing states of the cortical slow oscillation correspond to neuronal phase transitions. By analyzing intracellular recordings of the membrane potential during the cortical slow oscillation in rats, we quantify the temporal fluctuations in power and the frequency centroid of the power spectrum in the period of time before “down” to “up” transitions. By taking appropriate averages over such events, we present these statistics as a function of time before transition. The results demonstrate an increase in fluctuation power and time scale broadly consistent with the slowing of systems close to phase transitions. The analysis is complicated and limited by the difficulty in identifying when transitions begin, and removing dc trends in membrane potential

Single mother families : a participant observation study of human service agencies, organizations / by Melissa Reynolds.

The purpose of this mixed methods study was to better understand single mother families by integrating both qualitative data describing the lived experiences and needs of single mother families, with quantitative data detailing the formal services/programs currently available to meet these needs of single mother families living in Thunder Bay, Ontario, Canada. Qualitative analysis consisted of continual reflection and interpretation of day-to-day life experiences of 8 young single mother families through participant observations for a total of 180 hours of participant observation. In the quantitative approach, statistical analysis using SPSS 15.0 was completed on survey data from 30 human service agencies and organizations to learn about their extent of involvement with services/programs for single mother families in Thunder Bay. Analysis of the participant observation data revealed that the single mothers demonstrated resourcefulness, dignity, caution, astuteness, maturity, adaptability, coping, and tenacity in maintaining daily family living, along with hopefulness towards their futures. Additionally, the single mothers often relied on support from family and friends to maintain and provide for their families. The results of the statistical analysis revealed that only 33 percent of the agencies/organizations provided special services/programs for single mother families and 70 percent of these agencies/organization provided regular programs in which single mother families are eligible to participate. From the perspective of the experiences of the single mother families it was revealed that the needs of single mother families living in Thunder Bay are not sufficiently met by the services/programs available

"Turn-of-the-Nut" Method Is Not Appropriate for Use in Cancellous Bone.

Author version made available in accordance with publisher policy.OBJECTIVE: The level to which bone screws are tightened is determined subjectively by the operating surgeon. It is likely that the tactile feedback that surgeons rely on is based on localized tissue yielding, which may predispose the screw-bone interface to failure. A limited number of studies have investigated the ratio between clinical tightening torque and stripping torque. The purpose of this study was to measure, for the first time, the ratio between yield torque (T yield) and stripping torque (T max) during screw insertion into the cancellous bone and to compare these torques with clinical levels of tightening reported in the literature. Additionally, a rotational limit was investigated as a potential end point for screw insertion in cancellous bone. METHODS: A 6.5-mm outer diameter commercial cancellous bone screw was inserted into human femoral head specimens (n = 89). Screws were inserted to failure, while recording insertion torque, compression under the screw head, and rotation angle. RESULTS: The median, interquartile ranges, and coefficient of variation were calculated for each of the following parameters: T yield, T max, T yield/T max, slope, T plateau, and rotation angle. The median ratio of T yield/T max and rotation angle was 85.45% and 96.5 degrees, respectively. The coefficient of variation was greatest for the rotation angle compared with the ratio of T yield/T max (0.37 vs. 0.12). CONCLUSIONS: The detection of yield may be a more precise method than the rotation angle in cancellous bone; however, bone-screw constructs that exhibit a T yield close to T max may be more susceptible to stripping during insertion. Future work can identify factors that influence the ratio of T yield/T max may help to reduce the incidence of screw stripping

Time-elapsed screw insertion with microCT imaging

Author version made available following 12 month embargo from date of publication (18 Dec 2015) in accordance with Publisher copyright policy. Licensed under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Time-elapsed analysis of bone is an innovative technique that uses sequential image data to analyze bone mechanics under a given loading regime. This paper presents the development of a novel device capable of performing step-wise screw insertion into excised bone specimens, within the microCT environment, whilst simultaneously recording insertion torque, compression under the screw head and rotation angle. The system is computer controlled and screw insertion is performed in incremental steps of insertion torque. A series of screw insertion tests to failure were performed (n=21) to establish a relationship between the torque at head contact and stripping torque (R2=0.89). The test-device was then used to perform step-wise screw insertion, stopping at intervals of 20%, 40%, 60% and 80% between screw head contact and screw stripping. Image data-sets were acquired at each of these time-points as well as at head contact and post-failure. Examination of the image data revealed the trabecular deformation as a result of increased insertion torque was restricted to within 1 mm of the outer diameter of the screw thread. Minimal deformation occurred prior to the step between the 80% time-point and post-failure. The device presented has allowed, for the first time, visualization of the micro-mechanical response in the peri-implant bone with increased tightening torque. Further testing on more samples is expected to increase our understanding of the effects of increased tightening torque at the micro-structural level, and the failure mechanisms of trabeculae

How does innovation emerge in a service ecosystem?

To advance the study of innovation in complex settings, this study integrates the innovation, institutional theory, philosophy, and service-dominant logic literatures. Exploring the emergence of innovation and service ecosystem dynamics, researchers take an abductive approach anchored in over 4 years of case study data regarding a high technology solution in an Internet-of-Things setting. By framing innovation as a systemic process, the study reveals that (1) institutional reconciliation is an overlooked phase of innovation, (2) ideas are refined by four types of institutional reconciliation pressures (tensions, divergences, expected value, and service), and (3) innovation is influenced by plasticity in four ways (recursivity, temporality, complementarity, and continuity). Based on these findings, the authors outline a research agenda regarding four principles of innovation as a systemic process. The findings suggest that managers should nurture norms, rules, and beliefs through a systemic process that facilitates the emergence of innovation

More than teacher directed or child initiated: Preschool curriculum type, parent involvement, and children's outcomes in the child-parent centers.

This study investigated the contributions of curriculum approach and parent involvement to the short- and long-term effects of preschool participation in the Title I Chicago Child-Parent Centers. Data came from the complete cohort of 989 low-income children (93% African American) in the Chicago Longitudinal Study, who attended preschool in the 20 Child-Parent Centers in 1983-1985 and kindergarten in 1985-1986. We found that implementation of an instructional approach rated high by Head Teachers in teacher-directed and child-initiated activities was most consistently associated with children’s outcomes, including school readiness at kindergarten entry, reading achievement in third and eighth grades, and avoidance of grade retention. Parent involvement in school activities, as rated by teachers and by parents, was independently associated with child outcomes from school readiness at kindergarten entry to eighth grade reading achievement and grade retention above and beyond the influence of curriculum approach. Findings indicate that instructional approaches that blend a teacher-directed focus with child-initiated activities and parental school involvement are origins of the long-term effects of participation in the Child-Parent Centers