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Prediction of geomagnetic variability depends on the accuracy of geomagnetic field modeling, dynamical modeling of source regions that contribute to geomagnetic signals, and advanced assimilation algorithms that combine effectively the results of geomagnetic field and dynamic models to make accurate estimates of the dynamic states of the sources and, therefore, accurate forecast of geomagnetic variations. Here, an overview of recent research efforts in these three research areas is provided, focusing primarily on geomagnetic variations from the dynamic outer core and from solar and lunar tidal effects, but also including a review of relevant research results and developments. Prediction of weak but periodic tidal phenomena, and of strong but chaotic secular variation showcases two very important new developments which will lead to new opportunities in geomagnetic research and application.
New cranial and postcranial material of the baenid turtle Neurankylus from the Paleocene Nacimiento Formation (Torrejonian NALMA) of northwestern New Mexico represents a new species, Neurankylus torrejonensis. The material consists of a fragmented but mostly complete skull, a partial carapace and plastron, portions of both humeri, a partial pelvis, a complete right femur, and a distal phalanx. The small, undivided cervical scale, wide vertebrals, complete ring of marginals, and large size (carapace length 520 mm) diagnose the new taxon as belonging to Neurankylus. The narrow fifth vertebral scale and scalloped posterior shell margin reveal affinities with Neurankylus baueri Gilmore, 1916, which is known from Campanian sediments in New Mexico and Utah. The holotype of Neurankylus torrejonensis is the youngest known specimen of the Neurankylus lineage, which is known to reach at least back to the Late Cretaceous (Santonian). A nearly complete species-level analysis of baenids confirms the basal placement of Neurankylus outside of Baenodda and the split of Baenodda into two primary subclades, herein named Palatobaeninae and Eubaeninae.
Little is known about the impact of corn and energy prices on the profitability of irrigating corn in Tennessee. We evaluated the probability of a positive net present value (NPV) for center-pivot irrigation in Tennessee corn production. Three corn price series were employed to evaluate the effects of the shift in corn prices on the feasibility of irrigation. The recent rise in corn prices increased the probability of NPV being positive for irrigation investment. Future corn prices will need to remain high for investment in center-pivot irrigation to remain profitable under Tennessee growing conditions.
Restoration in Mediterranean-climate grasslands is strongly impeded by lack of native propagules and competition with exotic grasses and forbs. We report on a study testing several methods for exotic plant control combined with planting native grasses to restore prairies in former agricultural land in coastal California. Specifically we compared tarping (shading out recently germinated seedlings with black plastic) once, tarping twice, topsoil removal, herbicide (glyphosate), and a control treatment in factorial combinations with or without wood mulch. Into each treatment we planted three native grass species (Elymus glaucus, Hordeum brachyantherum, and Stipa pulchra) and monitored plant survival and cover for three growing seasons. Survival of native grass species was high in all treatments, but was slightly lower in unmulched soil removal and control treatments in the first 2 yr. Mulching, tarping, and herbicide were all effective in reducing exotic grass cover and enhancing native grass cover for the first 2 yr, but by the third growing season cover of the plant guilds and bare ground had mostly converged, primarily because of the declining effects of the initial treatments. Mulching and tarping were both considerably more expensive than herbicide treatment. Topsoil removal was less effective in increasing native grass cover likely because soil removal altered the surface hydrology in this system. Our results show that several treatments were effective in enhancing native grass establishment, but that longer term monitoring is needed to evaluate the efficacy of restoration efforts. The most appropriate approach to controlling exotics to restore specific grassland sites will depend not only on the effectiveness, but also on relative costs and site constraints.
Deterministic and stochastic yield response plateau functions were estimated to determine the expected profit-maximizing nitrogen rates, yields, and net returns for corn grown after corn, cotton, and soybeans. The stochastic response functions were more appropriate than their deterministic counterparts, and the linear response stochastic plateau described the data the best. The profit-maximizing nitrogen rates were similar for corn after corn, cotton, and soybeans, but relative to corn after corn, the expected corn yield plateaus increased by 12% and 16% after cotton and soybeans, respectively. Expected net returns increased for corn after cotton and soybeans relative to corn after corn.
Pulses, including peas, have long been important components of the human diet due to their content of starch, protein and other nutrients. More recently, the health benefits other than nutrition associated with pulse consumption have attracted much interest. The focus of the present review paper is the demonstrated and potential health benefits associated with the consumption of peas, Pisum sativum L., specifically green and yellow cotyledon dry peas, also known as smooth peas or field peas. These health benefits derive mainly from the concentration and properties of starch, protein, fibre, vitamins, minerals and phytochemicals in peas. Fibre from the seed coat and the cell walls of the cotyledon contributes to gastrointestinal function and health, and reduces the digestibility of starch in peas. The intermediate amylose content of pea starch also contributes to its lower glycaemic index and reduced starch digestibility. Pea protein, when hydrolysed, may yield peptides with bioactivities, including angiotensin I-converting enzyme inhibitor activity and antioxidant activity. The vitamin and mineral contents of peas may play important roles in the prevention of deficiency-related diseases, specifically those related to deficiencies of Se or folate. Peas contain a variety of phytochemicals once thought of only as antinutritive factors. These include polyphenolics, in coloured seed coat types in particular, which may have antioxidant and anticarcinogenic activity, saponins which may exhibit hypocholesterolaemic and anticarcinogenic activity, and galactose oligosaccharides which may exert beneficial prebiotic effects in the large intestine.
New and reemerging infectious diseases, such as pandemic viruses and resistant bacteria, pose a serious threat in the 21st century. Some of these agents represent global security threats. This review provides an overview of diagnostic challenges presented by pandemic influenza and biothreat agents. The article summarizes recent pandemics and disease outbreaks, point-of-care influenza diagnostic tests, biothreat agents, biothreat instrument systems, and technologies in development. It highlights how medical innovation and health care initiatives can help prepare health care professionals and public health personnel to handle future crises. Based on gap analysis for current point-of-care testing deficiencies, it concludes with policy recommendations that will enhance preparedness. (Disaster Med Public Health Preparedness. 2009;3(Suppl 2):S193–S202)