Video Evidence That London Infants Can Resettle Themselves Back to Sleep After Waking in the Night, as well as Sleep for Long Periods, by 3 Months of Age

Objective: Most infants become settled at night by 3 months of age, whereas infants not settled by 5 months are likely to have long-term sleep-waking problems. We assessed whether normal infant development in the first 3 months involves increasing sleep-period length or the ability to resettle autonomously after waking in the night. Methods: One hundred one infants were assessed at 5 weeks and 3 months of age using nighttime infrared video recordings and parental questionnaires. Results: The clearest development was in sleep length; 45% of infants slept continuously for 5 hours or more at night at 3 months compared with 10% at 5 weeks. In addition, around a quarter of infants woke and resettled themselves back to sleep in the night at each age. Autonomous resettling at 5 weeks predicted prolonged sleeping at 3 months suggesting it may be a developmental precursor. Infants reported by parents to sleep for a period of 5 hours or more included infants who resettled themselves and those with long sleeps. Three-month olds fed solely breast milk were as likely to self-resettle or have long sleep bouts as infants fed formula or mixed breast and formula milk. Conclusions: Infants are capable of resettling themselves back to sleep in the first 3 months of age; both autonomous resettling and prolonged sleeping are involved in “sleeping through the night” at an early age. Findings indicate the need for physiological studies of how arousal, waking, and resettling develop into sustained sleeping and of how environmental factors support these endogenous and behavioral processes

FARMERS' PERCEPTIONS OF SPATIAL YIELD VARIABILITY AS INFLUENCED BY PRECISION FARMING INFORMATION GATHERING TECHNOLOGIES

This study evaluated how farmers' perceptions of spatial yield variability are influenced by precision technologies. Farmer estimates from a mail survey were regressed on use of alternative information technologies and personal characteristics. Results indicate that farmers who adopted yield monitors with GPS for cotton perceived significantly higher spatial yield variability.Research and Development/Tech Change/Emerging Technologies,

Effects of Herbicide-Resistant Technology Fees on the Plant Population Decision for Cotton Production

This study evaluated effects on cotton net revenues of four herbicide-resistant technology policies used since 1996 by Monsanto. Results indicate that farmers may have an incentive to switch from narrow-row to wide-row cotton and to use a lower plant density when the technology fee is tied to the seeding rate.Farm Management,

The Variable-Rate Decision for Multiple Inputs with Multiple Management Zones

Research has evaluated the relative profitability of variable-rate versus uniform-rate application of a single input in fields with multiple management zones. This paper addresses the variable-rate decision for multiple inputs. The decision-making framework is evaluated for nitrogen and water applied to irrigated cotton in fields with three management zones.Crop Production/Industries,

OPTIMAL PLANT POPULATION FOR ULTRA-NARROW-ROW COTTON PRODUCTION AS INFLUENCED BY LINT AND TRANSGENIC SEED PRICES

Farmers are concerned about the high costs of transgenic seed and technology fees associated with the large plant population densities recommended for ultra-narrow row cotton. This study evaluated the effects of alternative plant population density decision criteria on net revenues under different lint price and transgenic seed cost scenarios. Results indicate that farmers may be able to maximize profits by seeding for a target plant population density of approximately 15.5 plants m-2.Crop Production/Industries,

The Variable-Rate Input Application Decision for Multiple Inputs with Interactions

Research has evaluated the relative profitability of variable-rate (VRT) versus uniform-rate (URT) application of a single input in fields with multiple management zones. This study addresses map-based VRT decisions for multiple inputs in fields with multiple management zones. The decision-making framework is illustrated for nitrogen and water applied to irrigated cotton in fields with three management zones. Results suggest traditional methods of determining VRT application of a single input may by suboptimal if interactions exist among VRT inputs and URT inputs. Implications are that a systems approach to multiple-input VRT decisions can produce increased net returns to VRT.breakeven analysis, cotton, economic feasibility, multiple-inputs, precision farming, variable-rate technology, Crop Production/Industries,

Extensive lava flow fields on Venus: Preliminary investigation of source elevation and regional slope variations

Large-volume lava flow fields have been identified on Venus, the most areally extensive of which are known as fluctus and have been subdivided into six morphologic types. Sheetlike flow fields (Type 1) lack the numerous, closely spaced, discrete lava flow lobes that characterize digitate flow fields. Transitional flow fields (Type 2) are similar to sheetlike flow fields but contain one or more broad flow lobes. Digitate flow fields are divided further into divergent (Types 3-5) and subparallel (Type 6) classes on the basis of variations in the amount of downstream flow divergence. As a result of our previous analysis of the detailed morphology, stratigraphy, and tectonic associations of Mylitta Fluctus, we have formulated a number of questions to apply to all large flow fields on Venus. In particular, we would like to address the following: (1) eruption conditions and style of flow emplacement (effusion rate, eruption duration), (2) the nature of magma storage zones (presence of neutral buoyancy zones, deep or shallow crustal magma chambers), (3) the origin of melt and possible link to mantle plumes, and (4) the importance of large flow fields in plains evolution. To answer these questions we have begun to examine variations in flow field dimension and morphology; the distribution of large flow fields in terms of elevation above the mean planetary radius; links to regional tectonic or volcanic structures (e.g., associations with large shield edifices, coronae, or rift zones); statigraphic relationships between large flow fields, volcanic plains, shields, and coronae; and various models of flow emplacement in order to estimate eruption parameters. In this particular study, we have examined the proximal elevations and topographic slopes of 16 of the most distinctive flow fields that represent each of the 6 morphologic types

Adoption of Conservation-Tillage Methods and Genetically Modified Cotton

Adoption of herbicide-tolerant cotton and conservation tillage may be simultaneously related. Bayes' theorem and a two-equation logit model were used to test the simultaneity hypothesis. Evidence for Tennessee suggests that adoption of these technologies reduced residual herbicide use and soil erosion more than if adoption of these technologies were independent.Bayes' theorem, conservation tillage, cotton, genetically modified crops, herbicide tolerant crops, simultaneous logit model, technology adoption, Crop Production/Industries, Q12, Q16, Q24, O33,

Adoption of No-Tillage Practices, Other Conservation-Tillage Practices and Herbicide-Resistant Cotton Seed, and Their Synergistic Environmental Impacts

If adoption of herbicide-resistant seed and adoption of conservation-tillage practices are determined simultaneously, adoption of herbicide-resistant seed could indirectly reduce soil erosion and adoption of conservation-tillage practices could indirectly reduce residual herbicide use and increase farm profits. Our objective was to evaluate the relationship between these technologies for Tennessee cotton production. Evidence from simultaneous estimation of a trinomial logit model for adoption of no-tillage, other conservation-tillage, and conventional-tillage practices and a binomial logit model for adoption of herbicide-resistant and conventional cotton seed suggests a simultaneous relationship. The elasticity for acreage in herbicide-resistant seed with respect to the probability of adopting conservation-tillage practices was 3.98. The elasticities for acreages in no-tillage practices and other conservation-tillage practices with respect to the probability of adopting herbicide-resistant cotton seed were 0.34 and 0.10, respectively. Adoption of herbicide-resistant cotton seed in Tennessee reduced soil erosion by 9.2 million tons through its effects on adoption of conservation-tillage practices. By 2004, increases in adoption of conservation-tillage practices increased adoption of herbicide-resistant cotton seed by 445 thousand acres, substituting non-residual herbicides for residual herbicides on those cotton acres.Environmental Economics and Policy,

Factors Affecting Hay Supply and Demand in Tennessee

Understanding the interactions between supply and demand for hay is important because of hay’s significance to the agricultural sector and economy, and because hay is an important crop on highly erodible soils. As an example, Tennessee has the most erodible cultivated cropland in the United States (Denton, 2000), nearly half of the state’s current CRP acreage contracts are set to expire in 2007 (U.S. Department of Agriculture, 2006), and hay is one of the most economically important crops produced in the state (U.S. Department of Agriculture, 2004). Cross (1999) attributed the upward trend in Tennessee hay acreage since 1980 to an increasing number of farmers who were searching for alternative production activities, such as hay, pasture and livestock, to replace row crops on erodible soils (U.S. Congress, House of Representatives and Senate, 2002). Hay ranked tenth in value of receipts in Tennessee at $49.25 million in 2006 and cattle and calf production ranked first at$500 million. Hay ranked second in value of production at $262 million in 2003 and averaged$248 million over a five period from 2002 – 2006. Underscoring the importance of hay in Tennessee was the state’s national ranking of fourth in the production of other hay (excluding alfalfa) at 4.25 million tons in 2006 (U.S. Department of Agriculture, 2007). To quantify these supply and demand relationships, one must understand the characteristics of hay markets. Markets are usually localized because of the weight and bulky physical characteristics of hay. Although hay species are not identical, in many livestock production situations most are close substitutes, with the possible exception of alfalfa hay. In Tennessee, alfalfa is a differentiated hay product used mostly by dairy and equine producers. Nevertheless, alfalfa constituted only 2.5% of all hay produced in Tennessee in 2003 (U.S. Department of Agriculture, 2004) and its price tends to move proportionally with other hay prices; thus, for modeling purposes alfalfa and other hay can be aggregated as in Shumway’s (1983) study of Texas field crops and treated as a composite commodity (Nicholson, 2005) called hay. In 2002, 47,000 operations within the state produced forage, while on the demand side, 50,000 operations were involved in beef and dairy production with another 24,000 equine operations (U.S. Department of Agriculture, 2004). Despite the lack of national and state central markets for hay (Cross, 1999), buyers and sellers seem to be aware of the current prices in their area. Word of mouth, a hay directory website (Tennessee Farm Bureau Federation, 2005), and the Farm Facts bulletin (Tennessee Agricultural Statistics Service, 2004) are among the primary outlets for price discovery (Rawls, September 2004). Hay producers are typically assumed to be price takers (Shumway, 1983) because of the large numbers of sellers and buyers; nevertheless, search costs and price differentials can result from the lack of a central market. Even though hay and livestock producers have avenues for price determination in the short run, they have little information about what causes supply and demand for hay to change from year to year. The overall objective of this research was to illustrate how the understanding of hay markets can provide valuable information to hay and livestock producers and agricultural policymakers. Using the Tennessee hay market as an example, the specific objectives were to: 1) determine the factors that influence Tennessee hay supply and quantify their effects, 2) determine the factors that influence Tennessee hay demand and quantify their effects, and 3) briefly illustrate the importance of hay supply and demand information to policymakers. Estimating factors that influence hay supply and demand can help to provide hay and livestock producers with valuable information for making more informed business decisions and policymakers with insight into how proposed agricultural policies might affect hay and livestock producers. To accomplish the objectives, Tennessee hay supply and demand were modeled econometrically, and the coefficients of the models were used to quantify hay acreage, yield, and price responses to the factors that influence the Tennessee hay market. The results were then used to briefly illustrate the potential impacts on the 2008 Tennessee hay price from the retirement of Conservation Reserve Program (CRP) acreage in 2007. Hay acreage proved to be fairly unresponsive to output and input prices in both the short and long runs. The weak response of hay acreage to own and substitute crop prices may result from many hay producers also being cattle producers that harvest their own hay in an effort to guarantee a reliable supply of roughage to feed their herds throughout the winter months. They might be willing to give up potentially higher profits from a production alternative to avert the risk of feed shortages for their cattle. The hay price appeared to be responsive to real per capita income with a price flexibility of 1.55. This finding is reasonable because an increase in real per capita income results in more purchasing power for a typical household. As purchasing power increases, one would expect beef consumption to increase because beef is a normal good (Schroeder and Mark, 1999). Increased beef consumption would positively influence the derived demand for beef production inputs; hence, increased demand for hay. A weak response of hay price to the quantity of hay produced (HPRODt) could be explained by the hay market structure. First, some livestock farmers may produce large amounts of hay for their own livestock, much of which is not sold on the market. These farmers may be able to produce hay at a lower cost than market price, or they may be willing to forgo the potential cost savings from buying hay from an off-farm source to avert the risk of feed shortages for their cattle. Additionally, unlike the market for corn or cattle, the hay market is much less organized and structured. Farmers producing hay for the cash market have no nearby and convenient grain elevator or auction market at which to sell their product. Weak response to changes in hay quantity and price suggests that hay farmers may not be driven solely by the profit motive. Instead, other motives may also enter into their objective functions as utility maximizers.acreage response, derived demand, elasticities, hay, inverse demand function, price flexibilities, yield response, Crop Production/Industries, Demand and Price Analysis, D,