EC71-771 Furrow Irrigation of Nebraska Soils

Extension Circular 71-771: Furrow Irrigation of Nebraska Soils; how much water to apply, distributing water uniformly, furrow slope, length of run, intake rates, furrow stream size, alternate furrow irrigation, and instruction for how to use tables provided

Tracking Transfer: New Measures of Institutional and State Effectiveness in Helping Community College Students Attain Bachelor’s Degrees

This report is designed to help improve transfer student outcomes by helping institutional leaders and policymakers better understand current outcomes and providing them with metrics for benchmarking their performance. The authors propose a common set of metrics for measuring the effectiveness of two- and four-year institutions in enabling degree-seeking students who start college at a community college to transfer to four-year institutions and earn bachelor’s degrees. These include three community college measures—transfer-out rate, transfer-with-award rate, and transfer-out bachelor’s completion rate—and one measure for four-year institutions—transfer-in bachelor’s completion rate. They also examine a fifth measure: the overall rate at which the cohort of students who start at a community college in a given state go on to earn a bachelor’s degree from a four-year institution. Using a rich set of data from the National Student Clearinghouse on more than 700,000 degree-seeking students who first enrolled in community college in 2007, the authors calculated the average outcomes on these measures six years after these students entered college. Performance on all measures varied widely across individual institutions and states. Institutional characteristics were not strongly correlated with student outcomes at community colleges, suggesting that institutions that serve transfer students well can have better-than-expected outcomes even if they have relatively few resources or more disadvantaged students. Among four-year institutions, transfer students had better outcomes at public institutions, very selective institutions, and institutions with higher socioeconomic status students. Lower income transfer students had worse outcomes than higher income students on almost all measures, though in a few states, the success gap between lower and higher income students was small or nonexistent

Nuclear magnetic resonance spectroscopy: Abnormal splitting of ethyl groups due to molecular asymmetry

Nuclear magnetic resonance (n.m.r.) spectroscopy provides an excellent means for qualitative identification of ethyl groups by use of the familiar three-four pattern of spin-spin splitting (1). It has been observed previously (2) that the methylene protons of systems of the type R-CH2-CR1R2R3 (where R1 can be the same as R or different) may be magnetically nonequivalent and display AB rather than A2-type spectra (3). We now wish to report several examples of this type of behavior with ethyl groups, particularly ethoxy groups, knowledge of which could be important to anyone using n.m.r. for organic qualitative analysis

Economics of farmer early retirement policy

We estimate the structural effects, costs and potential efficiency gains that might arise from the introduction of an Early Retirement Scheme for farmers in Northern Ireland using data from the Farm Business Survey and a separate survey of 350 farmers aged between 50 and 65. Modelling results suggest that farm scale is a significant determinant of profit per hectare but that operator age is not. The economic gains from releasing land through a Scheme were conditional on transfers bringing about significant farm expansion and changes in land use. When these conditions were satisfied pensions payments of only about one-third the statutory maximum could be justified. Survey responses indicated that participation in the Scheme would bring forward farmers' retirement age by an average of four years. Moreover, 'deadweight' payments would equate to about 23 per cent of potential total expenditure. Overall, the economic case for the introduction of an Early Retirement Scheme to Northern Ireland is judged to be weak

Early Momentum Metrics: Leading Indicators for Community College Improvement

As community colleges across the country implement large-scale reforms to improve student success, they need timely and actionable metrics to determine if the changes they are making in a given year or term will likely improve student outcomes in the long run. In this brief, the authors examine how well nine measures of students’ progress in their first year predict student completion in subsequent years, and thus how suitable these early momentum metrics are as leading indicators of the effectiveness of institutional reforms. Based on analysis of student data from all community colleges in three states, the authors find that early momentum metrics do predict longer term success for students. They also find that a key factor in low completion rates, as well as in equity gaps in completion rates, is that many students do not gain early momentum in their first year. College outcomes would be substantially higher if more students met early momentum metrics. These findings indicate the need for comprehensive reforms to community college organization and practice to help more students gain early momentum on their way to earning a credential

Is It Really Cheaper to Start at a Community College? The Consequences of Inefficient Transfer for Community College Students Seeking Bachelor’s Degrees

For many students who intend to complete a bachelor’s degree, the savings from starting their undergraduate education at a community college is a major factor in their college choice. Yet, given inefficiencies in pathways through college and in the credit transfer process, initially attending a two-year college may be a false economy. In this paper we investigate whether it is more efficient for students to start at a two-year or four-year college if their intent is to complete a bachelor’s degree. We use data from two state systems, including term-by-term course-level information with matching student demographics and degree records on entering cohorts of students at each state’s public two- and four-year institutions. We combine these data with cost and tuition data to estimate the relative efficiency of starting at a two-year versus a four-year college. We find that the optimal choice about where to start varies across a number of dimensions: low rates of credit transfer are important, but the most salient factor is the diversionary effect of two-year colleges on ever transferring to a four-year college. Sensitivity testing and break-even analyses illustrate how findings vary across student pathways

On-Chip Cavity Optomechanical Coupling

On-chip cavity optomechanics, in which strong co-localization of light and mechanical motion is engineered, relies on efficient coupling of light both into and out of the on-chip optical resonator. Here we detail our particular style of tapered and dimpled optical fibers, pioneered by the Painter group at Caltech, which are a versatile and reliable solution to efficient on-chip coupling. First, a brief overview of tapered, single mode fibers is presented, in which the single mode cutoff diameter is highlighted. The apparatus used to create a dimpled tapered fiber is then described, followed by a comprehensive account of the procedure by which a dimpled tapered fiber is produced and mounted in our system. The custom-built optical access vacuum chambers in which our on-chip optomechanical measurements are performed are then discussed. Finally, the process by which our optomechanical devices are fabricated and the method by which we explore their optical and mechanical properties is explained. It is our expectation that this manuscript will enable the novice to develop advanced optomechanical experiments.Comment: 31 pages, 9 figure