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Cover crops have increased in popularity in midwestern U.S. corn and soybean systems in recent years. However, little research has been conducted to evaluate how cover crops and residual herbicides are effectively integrated together for weed control in a soybean production system. Field studies were conducted in 2016 and 2017 to evaluate summer annual weed control and to determine the effect of cover crop biomass on residual herbicide reaching the soil. The herbicide treatments consisted of preplant (PP) applications of glyphosate plus 2,4-D with or without sulfentrazone plus chlorimuron at two different timings, 21 and 7 d prior to soybean planting (DPP). Cover crops evaluated included winter vetch, cereal rye, Italian ryegrass, oat, Austrian winter pea, winter wheat, and a winter vetch plus cereal rye mixture. Herbicide treatments were applied to tilled and nontilled soil without cover crop for comparison. The tillage treatment resulted in low weed biomass at all collection intervals after both application timings, which corresponded to tilled soil having the highest sulfentrazone concentration (171 ng g–1) compared with all cover crop treatments. When applied PP, herbicide treatments applied 21 DPP with sulfentrazone had greater weed (93%) and waterhemp (89%) control than when applied 7 DPP (60% and 69%, respectively). When applied POST, herbicide treatments with a residual herbicide resulted in greater weed and waterhemp control at 7 DPP (83% and 77%, respectively) than at 21 DPP (74% and 61%, respectively). Herbicide programs that included a residual herbicide had the highest soybean yields (≥3,403 kg ha–1). Results from this study indicate that residual herbicides can be effectively integrated either PP or POST in conjunction with cover crop termination applications, but termination timing and biomass accumulation will affect the amount of sulfentrazone reaching the soil.Nomenclature: 2,4-D; chlorimuron; glyphosate; sulfentrazone; Austrian winter pea, Pisum sativum ssp. arvense (L.) Poir; cereal rye, Secale cereal L.; corn, Zea mays L.; Italian ryegrass, Lolium perenne L. ssp. multiflorum (Lam.) Husnot; oat, Avena sativa L.; waterhemp, Amaranthus tuberculatus (Moq.) J. D. Sauer.; winter wheat, Triticum aestivum L.; winter vetch, Vicia villosa Roth ssp. varia (Host) Corb.; soybean, Glycine max (L.) Merr.

The ASCE/SEI 7 Standards Committee has incorporated a new Chapter 6, “Tsunami Loads and Effects,” in the 2016 edition of the ASCE 7 Standard, Minimum Design Loads and Associated Criteria fo...

Everyday communities seem to juggle their technology use largely through the contributions and knowledge brought by its members. This contrasts with work settings where there is a greater focus on strategic choices to acquire new technologies and competencies. We focus on how artifact ecologies are shaped in community settings by personal and community relationships, and on the methodological possibilities of understanding these communities for the purpose of design, and making informed technology choices in communities. We applied interview and visual mapping methods, before undertaking a ‘remapping’ process as part of our data analysis, thus contributing methodologically to the investigation of artifact ecologies at large and community artifact ecologies in particular. Theoretically, we extend the understanding of dynamics in artifact ecologies and highlight the ways these dynamics are shaped by the social interactions taking place, around technological artifacts, in everyday situations.

Contrary to the provisions in many seismic design codes, plate girder superstructures of steel bridges should be explicitly designed for lateral load to ensure the adequacy of the load path from the deck above the girders to the bearings below. These structures should either be designed to behave elastically, or allow selected components to yield (e.g., end crossframes). In the latter case, significant reductions in the lateral shears transmitted to the substructures may be achieved, but special detailing of the connection between the crossframe and the deck is necessary to protect the girders from distortion and the girder-deck joint from degradation.

We previously demonstrated that lesions of the nucleus accumbens (NAc) core enhanced locomotion and locomotor sensitization to repeated injections of nicotine in rats (Kelsey & Willmore, 2006). In this study, we compared the effects of separate lesions of the NAc core, NAc medial shell, and basolateral amygdala on context-specific locomotor sensitization to repeated injections of 0.4 mg/kg nicotine. Electrolytic lesions of the NAc core increased locomotion, and lesions of the core (but not the shell) and the basolateral amygdala enhanced context-specific locomotor sensitization by enhancing the development of sensitization in paired rats and decreasing expression in unpaired rats relative to sham-operated rats when challenged with an injection of 0.4 mg/kg nicotine in the locomotor chambers. These data are consistent with findings that the NAc core and the basolateral amygdala share a variety of behavioral functions and anatomical connections. The findings that lesions of these structures enhance context-specific locomotor sensitization while typically impairing other reward-related behaviors also indicate that the processes underlying locomotor sensitization and reward are not identical.

The food system of the 20th century has failed to eliminate the tragedy of malnutrition in developing countries. Partial explanations for this failure lie in 3 critical but often ignored realities about efforts to improve nutrition: 1) agriculture is likely to continue as the principal nutrient source for decades to come; 2) nutrition strategies have very important economic implications and to overlook them is to ask for disaster; and 3) economists need to take into account the nutritional implications of their plans. The biggest reality is actually the lack of communication between nutritionists and economists.

Ductile end cross frames have been shown to reduce the transverse seismic demand in composite steel plate girder bridge superstructures. However, the effectiveness of these cross frames is strongly influenced by the transverse flexibility of the superstructure and its capacity for potentially large relative transverse displacements between the deck slab and bearing supports. A simplified method is developed in this paper for the calculation of these displacements based on the elastic girder stresses and transverse girder stiffnesses, which are shown to compare well with results given by the finite element method. In addition the method is shown to give results that compare well with experimental data from a 0.4 scale model subject to shake table excitation. Parametric studies are then described that show typical I -girder superstructures are able to accommodate large transverse drifts (up to 17% of the girder height) while remaining in the elastic range. These large drifts are possible without distress to the slab-to-girder connection, by omitting shear studs over a short length of the girder at the support cross frame locations. Based on the above, a step-by-step procedure is proposed for evaluating the transverse displacement, stiffness and capacity of the steel girder superstructures in the region of the end and intermediate supports.

Unstiffened, unbraced steel beams used in bridge falsework are subjected to patch loads from timber or steel posts. This paper investigates the critical web limit states in these types of beams experimentally and through finite-element analysis. Existing equations were appropriate for calculating the web yielding and crippling capacity, as observed in experiments, except that a 1:1 stress gradient through the flange and fillet of the web is found to be more appropriate and conservative for web yielding than the 2.5:1 gradient assumed in the current AISC specifications. Lateral deformation of a beam flange, due to buckling of the web, was also observed experimentally. The capacity of the web for resisting lateral buckling can be calculated assuming that the web of the beam acts like a column with an appropriate effective area and length factor. The effect of accidental eccentricity between the flange and post is not significant if limited to three times the web thickness. Blocking is approximately 50% effective in increasing the web yielding and crippling capacity. Bracing or stiffeners should be used to prevent lateral buckling of a web where necessary.

An evaluation of a single story unprotected steel structure exposed to repeated fire during the training of fire fighters is described. Temperatures are monitored on the structure using resistance temperature detectors connected to a data acquisition system. Temperatures of up to 384 °C are measured in the steel of the structures, which are below levels likely to cause much degradation in stiffness or strength. Uniform heating of the columns was shown to result in minimal stresses in the structure as the columns were relatively free to deform axially. Differential temperatures, however, where one side of the member is heated by a greater amount than the opposite side of the member, resulted in stresses calculated using an elastic analysis, up to 16 times greater than the yield strength and can thus explain large permanent curvatures observed in the columns. Coupon tests on steel samples from the columns exposed to repeated fire showed some hardening of the steel, possibility attributed to the plastic deformations in the columns, although the ultimate strain in the material was not greatly affected. Based on the monitoring and analysis, no aspects of the structure are considered to present an immediate hazard to the safety of the users. However, without improved cooling, plastic deformation of some members is expected.

Recent field observations during bridge construction revealed excessive localized deformations in sill and cap beams that support falsework posts. Hence, possible limit states associated with flange and web deformations in W and HP sections subjected to patch loading are investigated in this paper. Critical limit states were found to be related to flange bending, post compression, and the interactions associated with patch loading between a beam flange and timber or steel post. Other limit states are associated with web deformations. Two alternative methods based on yield line analyses that establish upper-bound limiting loads for these limit states are proposed. The first method accounts for an interaction between flange bending and post compression strength, whereas the second method uses an effective bearing area of the post. The former method is most effective in characterizing flange–timber posts interactions, while the effective bearing area method was found to be more accurate for steel posts. For beams with relatively thick webs, such as those typically used in bridge falsework, the web was found to have a greater capacity than the flange and post, with the critical web limit state due to web yielding. It was shown that current recommended equations were appropriate with modifications to account for the patch loading condition.

The use of an intraoperative lung-protective ventilation strategy through tidal volume (TV) size reduction and positive end-expiratory pressure (PEEP) has been increasingly investigated. In this article, we describe the current intraoperative lung-protective ventilation practice patterns and trends.By using the Multicenter Perioperative Outcomes Group database, we identified all general endotracheal anesthetics from January 2008 through December 2013 at 10 institutions. The following data were calculated: (1) percentage of patients receiving TV10 mL/kg predicted body weight (PBW); (2) median initial and overall TV in mL/kg PBW and; (3) percentage of patients receiving PEEP ≥ 5 cm H2O. The data were analyzed at 3-month intervals. Interinstitutional variability was assessed.A total of 330,823 patients met our inclusion criteria for this study. During the study period, the percentage of patients receiving TV10 mL/kg PBW was reduced for all patients (26% to 14%) and in the subpopulations of obese (41% to 25%), short stature (52% to 36%), and females (39% to 24%; all P values0.001). There was a significant reduction in TV size (8.90-8.20 mL/kg PBW, P0.001). There was also a statistically significant but clinically irrelevant difference between initial and overall TV size (8.65 vs 8.63 mL/kg PBW, P0.001). Use of PEEP ≥ 5 cm H2O increased during the study period (25%-45%, P0.001). TV usage showed significant interinstitutional variability (P0.001).Although decreasing, a significant percentage of patients are ventilated with TV10 mL/kg PBW, especially if they are female, obese, or of short stature. The use of PEEP ≥ 5 cm H2O has increased significantly. Creating awareness of contemporary practice patterns and demonstrating the efficacy of lung-protective ventilation are still needed to optimize intraoperative ventilation.

Male Sprague-Dawley rats were trained and tested in the fear-potentiated startle (FPS) paradigm to examine the involvement of the bed nucleus of the stria terminalis (BST) in the expression of conditioned fear. Studies were designed to (a) detect physiological changes in the BST that might correlate with different levels of FPS expression and (b) determine if chemical inactivation of the BST with muscimol (1 ng) had any effect on FPS expression. The data suggest that the BST plays a role in the expression of conditioned fear and that GABA-mediated inhibition at this level may influence the level of this expression.

The neuropeptide corticotropin-releasing factor (CRF) is believed to play a role in a number of psychiatric conditions, including anxiety disorders and depression. In the present study, male Sprague Dawley rats were used to examine the behavioral effects of altering dopamine transmission on CRF-enhanced startle, a behavioral assay believed to reflect stress- or anxiety-like states. Systemic administration of the selective dopamine D1receptor antagonist SCH 23390 [R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride] (0, 0.01, 0.05, 0.1, 0.5 mg/kg) dose dependently blocked the effect of CRF (1 μg, i.c.v.) on startle at doses that had no effect on baseline startle response. Immunohistochemical studies showed that most CRF-containing cells in the dorsolateral division of the bed nucleus of the stria terminalis (BSTld), part of the critical brain area mediating CRF-enhanced startle, are surrounded by a dense plexus of tyrosine hydroxylase (TH)-positive fibers. Intra-BSTld injections of the retrograde tracer Fluorogold (FG) into the TH field identified neurons in the major dopaminergic areas (A8-A10), but not the major noradrenergic areas [A5, A6 (locus ceruleus), A7], as a significant source of TH-positive innervation. The majority of FG-filled cells double-labeled for TH were found in the dorsocaudal A10 cell group (A10dc) located in the periaqueductal gray area. Together, these data suggest that neuronal regulation of the BSTld by specific dopaminergic pathways and receptors may be an important mechanism for controlling CRF-dependent moods and affective states. These data also suggest that compounds with D1receptor antagonist properties might have anxiolytic-like effects that could be useful for treating conditions associated with hyperactive CRF systems.

Ductile end cross frames have been proposed in the past as a seismic design and retrofit strategy for steel plate girder bridges. In this paper it is shown that with good connection details, single angles are able to undergo large cyclic deformations in excess of 6% average axial strain before failure occurs. Large-scale shake table experiments were performed on a straight steel I-girder bridge model to evaluate the performance of a superstructure with ductile end cross frames using single angle X braces. The cross frames exhibited no apparent overall strength degradation, but also a comparatively low postyield stiffness, allowing the cross frames to act as effective structural fuses. The measured base shear was 61% of the elastic base shear in response to 2.0 times the El Centro earthquake at an average drift of 3.4%. Large girder drifts were achieved without distress in the deck slab by removing selected studs between the slab and top flange of the girders at the end cross frame locations, with axial deformations in the angles well below their deformation capacity based on component experiments.

Ductile end cross frames have been proposed in the past for seismic design of steel plate girder bridges. In this paper buckling-restrained braces (BRBs) are investigated as ductile end cross frames and compared against the performance of yielding X braces. Component experiments on the BRBs showed that these braces dissipated energy very efficiently and have stable hysteretic behavior. Shake-table experiments on a large scale bridge model investigated the performance of braces with both pin-ended connections and fixed-end connections. Despite slippage, the pin-ended connections are considered more effective as flexural action in the relatively short braces is prevented. The base shear in the bridge model in response to 2.0 times the El Centro earthquake was 69% of the elastic base shear at an average drift of 2.5% during experiments. The relatively large deformation capacity of the BRBs, although not as great as the X braces, is necessary to achieve a significant reduction in base shear. The maximum cross frame displacements with the BRBs are consistently smaller than those in X braces at the same level of base shear.

The amygdala plays key roles in several aspects of addiction to drugs of abuse. This brain structure has been implicated in behaviours that reflect drug reward, drug seeking, and the aversive effects of drug withdrawal. Using a model that involves repeated cocaine injections to approximate 'binge' intoxication, we show in rats that during cocaine withdrawal, the impact of rewarding brain stimulation is attenuated, as quantified by alterations in intracranial self-stimulation (ICSS) behaviour. These behavioural signs of withdrawal are accompanied by enhancements of glutamatergic synaptic transmission within the lateral amygdala (LA) that occlude electrically induced long-term potentiation (LTP) in tissue slices. Synaptic enhancements during periods of cocaine withdrawal are mechanistically similar to LTP induced with electrical stimulation in control slices, as both forms of synaptic plasticity involve an increase in glutamate release. These results suggest that mechanisms of LTP within the amygdala are recruited during withdrawal from repeated exposure to cocaine. As such, they raise the possibility that the development and maintenance of addictive behaviours may involve, at least in part, mechanisms of synaptic plasticity within specific amygdala circuits.

Recent earthquakes have shown that a large magnitude, long period pulse is often prevalent in ground motion records at sites within a few kilometres of the active fault during an earthquake. Near-field earthquake ground motion containing forward directivity effects can result in a larger response in flexible structures, such as seismically isolated structures, compared to that predicted for conventional ground shaking. Hence, a study was performed on a number of generic seismically isolated structures designed to the 1997 Uniform Building Code, as well as a case study on the William Clayton building in Wellington, to determine the impact of near-field ground motion. In optimising the performance of the buildings for both near-field and original "design level" earthquakes, it is concluded that linear viscous dampers added to the existing isolation systems are effective in controlling the response during large magnitude near-field earthquakes with minimal impact on the design response. Additional viscous damping is more effective than hysteretic damping in limiting isolator displacements while also preventing an increase in base shear and floor accelerations for far-field "design level" earthquakes.

Two full-length glutamate-gated chloride channel (GluCl) cDNAs, encoding GluClalpha3 and GluClbeta subunits, were cloned from ivermectin-susceptible (IVS) and -resistant (IVR) Cooperia oncophora adult worms. The IVS and IVR GluClalpha3 subunits differ at three amino acid positions, while the IVS and IVR GluClbeta subunits differ at two amino acid positions. The aim of this study was to determine whether mutations in the IVR subunits affect agonist sensitivity. The subunits were expressed singly and in combination in Xenopus laevis oocytes. Electrophysiological whole-cell voltage-clamp recordings showed that mutations in the IVR GluClalpha3 caused a modest but significant threefold loss of sensitivity to glutamate, the natural ligand for GluCl receptors. As well, a significant decrease in sensitivity to the anthelmintics ivermectin and moxidectin was observed in the IVR GluClalpha3 receptor. Mutations in the IVR GluClbeta subunit abolished glutamate sensitivity. Co-expressing the IVS GluClalpha3 and GluClbeta subunits resulted in heteromeric channels that were more sensitive to glutamate than the respective homomeric channels, demonstrating co-assembly of the subunits. In contrast, the heteromeric IVR channels were less sensitive to glutamate than the homomeric IVR GluClalpha3 channels. The heteromeric IVS channels were significantly more sensitive to glutamate than the heteromeric IVR channels. Of the three amino acids distinguishing the IVS and IVR GluClalpha3 subunits, only one of them, L256F, accounted for the differences in response between the IVS and IVR GluClalpha3 homomeric channels.

Recent earthquakes exposed the vulnerabilities of steel plate girder bridges when subjected to ground shaking. This paper discusses the behavior of steel plate girder bridges during recent earthquakes such as Petrolia, Northridge, and Kobe. The paper also discusses the recent experimental and analytical investigations that were conducted on steel plate girder bridges and their components. Results of these investigations showed the importance of shear connectors in distributing and transferring the lateral forces to the end and intermediate cross frames. Also, these investigations showed the potential of using end cross frames as ductile elements that can be used to dissipate the earthquake input energy. The paper also gives an update on specifications and guidelines for the seismic design of steel plate girder bridges in the United States.

The last decade of destructive tsunamis in the Indian Ocean, and Pacific Ocean near Samoa, Chile and Japan have demonstrated the increasing vulnerability of coastal populations and built infrastructure to this hazard. In the United States, a new chapter has been developed for the ASCE 7 loading standard to design important buildings and other structures for tsunami loads and their effects. The application of the proposed ASCE 7 tsunami design provisions is demonstrated in the context of reinforced concrete and structural steel buildings analyzed for tsunami loads from the March 2011 Tohoku Tsunami, where the details of their structural performance were surveyed. Based on the case studies, the Energy Grade Line method of analysis is shown to be a reliable and generally conservative method to determine flow depth and velocity at a site based on a known maximum runup, with a modification to the Froude number coefficient for the bore condition. The load equations and conditions of ASCE 7 resulted in reasonable and conservative estimates of forces on components for hydrostatic buoyancy, lateral hydrostatic and hydrodynamic forces. Mid- to high-rise buildings, which are optimal for tsunami refuge, can be economically designed for life safety or better performance for large tsunamis with local strengthening of relatively few components.

Experiments are being performed on a 0.4 scale model of a steel girder bridge superstructure with a reinforced concrete deck to investigate means of improving the seismic performance of typical slab and girder bridges. During the early stages of experimentation, the need to understand the influence of composite action became apparent. Accordingly, an analytical study was undertaken. The first of several finite element analyses on a typical continuous four-span, four-girder bridge model assumed shear studs along the entire length of the bridge to provide full composite action. A second model omitted the shear connectors in the negative moment regions, a common design practice to avoid fatigue concerns in the top flange. It was found that the shear connectors in the fully composite model were sufficient to ensure composite action when subjected to transverse loading and provided an adequate load path through the superstructure and into the substructure. However, the lack of shear connectors in the negative moment regions caused the load to be transferred into the steel girders at the points of contraflexure, resulting in damage to these girders and inadequate formation of the ultimate limit state in the columns. The lack of composite action was also found to change the distribution of transverse shear forces in the cross frames, which is important for design of the end cross frames. Making the top chord of the cross frames composite with the deck, at the column bent locations, proved effective in minimizing damage to the superstructure.

The Tohoku Tsunami of March 11, 2011 caused tremendous damage to many coastal buildings, bridges and port facilities. During field surveys following this event, the authors documented a number of structures that were damaged to a near-collapse condition as a result of hydrodynamic loading. Analysis of survivor videos provided information on the tsunami flow characteristics at these locations, allowing for an assessment of current hydrodynamic loading expressions under full-scale conditions. Based on laboratory experiments performed at Oregon State University, the lead author and colleagues developed a new hydrodynamic loading expression for a broken bore striking a vertical wall [1]. This expression was applied to a case study of a large vertical reinforced concrete (RC) wall damaged by an incoming bore strike during the Tohoku Tsunami. The damaged wall is on the seaward side of a high-bay building in the Minami Gamou Sewage Treatment plant near the Sendai coastline. A non-linear finite element model of the building was subjected to the hydrodynamic pressure distribution derived from the laboratory experiments. It is shown by structural analysis of the wall that using this loading expression generates the same yielding response in the wall as observed in the field, as reflected in the deflected shape measured by LiDAR. Similar analysis using current Japan Tsunami design provisions indicates that these provisions are considerably more conservative from a structural perspective than is necessary to resist hydrodynamic loading from a tsunami bore. This paper presents the application of hydrodynamic loading by the leading edge of a bore, determined based on laboratory experiments, to the non-linear analysis of a reinforced concrete building damaged during the Tohoku Tsunami.

The purpose of this MBA Project is to investigate and provide a comprehensive overview of the current state of affairs with regard to the privatized security industry. The project focuses on a business plan that will cover three phases for a start-up company to enter the private security market. The purpose of Advanced Security Operations Corporation (ASOC) is to enter and profit from the growing Privatized Military Industry (PMI) trend. This proposal looks at establishing a network of centralized SWAT teams whose sole mission is to train and conduct SWAT operations. These teams will greatly increase the chance of success and minimize casualties, while greatly reducing cost. ASOC will use collaborative efforts with local, state and national law enforcement agencies in order to maximize this innovative and value-added plan. The goal of government should be to drastically reduce the cost of redundant and inefficient services. By following the trend to outsource services and create a privately run and centrally located SWAT Team, the local, state, and federal government can create a long term capability that is less expensive, yet has a greater capability for mission success. The costs-benefits and problems/solutions that would face such an endeavor are the focus of this project.

MBA Professional Report The purpose of this MBA Project is to investigate and provide a comprehensive overview of the current state of affairs with regard to the privatized security industry. The project focuses on a business plan that will cover three phases for a start-up company to enter the private security market. The purpose of Advanced Security Operations Corporation (ASOC) is to enter and profit from the growing Privatized Military Industry (PMI) trend. This proposal looks at establishing a network of centralized SWAT teams whose sole mission is to train and conduct SWAT operations. These teams will greatly increase the chance of success and minimize casualties, while greatly reducing cost. ASOC will use collaborative efforts with local, state and national law enforcement agencies in order to maximize this innovative and value-added plan. The goal of government should be to drastically reduce the cost of redundant and inefficient services. By following the trend to outsource services and create a privately run and centrally located SWAT Team, the local, state, and federal government can create a long term capability that is less expensive, yet has a greater capability for mission success. The costeffectiveness and problems/solutions that would face such an endeavor are the focus of this project. http://archive.org/details/theadvancedsecur109459893 Lieutenant, United States Navy Captain, United States Army Lieutenant, United States Naval Reserve Approved for public release; distribution is unlimited.

There are approximately 250,000 tank batteries in the United States1. These tanks store crude oil and condensate prior to transportation to sales via pipeline, barge or trucking. The sources of the vent gases from tanks are from flash, standing and working losses. There are approximately 8,000 to 10,000 mechanical vapor recovery units (VRUs) installed at oil production sites with four tanks typically connected to each VRU2. Most of these tanks are fixed-roof storage tanks. This project demonstrated the use of an alternative method for handling low-pressure natural gas that is typically vented to the atmosphere, flared or recovered with a mechanical compressor by oil and gas production facilities. This application used a venturi jet ejector as a device to compress natural gas from crude oil/water storage tanks to an intermediate pressure for use at the location or ultimate injection into the sales pipeline. Upon injection of the oil into the storage tanks, lower molecular weight hydrocarbons dissolved in the crude oil come out of solution or "flashes" when the pressure drops as the oil enters the tank. The storage tanks are typically downstream of a low-pressure vessel such as a two or three phase separator or heater treater. The hydrocarbons that flash include methane, ethane, volatile organic compounds and hazardous air pollutants. These gases collect in the plenum of the fixed roof storage tanks that are typically used in oil and gas production operations.

Using preparations derived from whole mouse brain, we have demonstrated that insecticidal arylalkylbenzhydrolpiperidines inhibit the depolarization of synaptoneurosomes as measured by rhodamine 6G fluorescence and block 22Na+ uptake into synaptosomes, when veratridine is used as the activator. These insecticides also have the ability to potently displace the binding of [3H]batrachotoxinin A 20-alpha-benzoate ([3H]BTX-B) to neuronal sodium channels in a concentration-dependent manner. The study compounds can be classified as competitive inhibitors of radioligand binding, since they decrease the affinity of [3H]BTX-B for site 2 without affecting the concentration of sites labelled by this radioligand. Our kinetic analyses revealed that at its IC50, the 4-carbomethoxyaminobenzyl-piperidine analogue reduces the rate of association of [3H]BTX-B with site 2, whereas higher concentrations were required to accelerate dissociation of the [3H]BTX-B:sodium channel complex. These results indicate an ability to interact with both non-activated and persistently activated states of the voltage-sensitive sodium channel, but higher affinity for the former. Such a profile also implies that inhibition of [3H]BTX-B binding to site 2 occurs via an allosteric mechanism. In addition, arylalkylbenzhydrolpiperidines interact with presynaptic voltage-sensitive calcium channels, since we demonstrate that they inhibit increases in [free Ca++] and 45Ca++ uptake when evoked by high KC1 concentration in mouse brain synaptosomal preparations. Such effects generally occur at concentrations that are higher than those required to inhibit sodium channels. Blockade of sodium and calcium channels may therefore contribute to the in vivo neurological effects observed in rodents exposed to these insecticides.

This paper discusses the use of high-power lasers to remotely process material for decommissioning and dismantlement of nuclear facilities. Process requirements are established and suitable laser systems are compared. The chemical oxygen- iodine laser was identified as the leading candidate for long term dismantlement activities because it offers a high-power, high-brightness beam that can be remotely delivered into radiation containment by optical fibers.

A recently discovered spider toxin (DTX9.2) induced a rapid paralysis when injected into insects. In neurophysiological experiments, DTX9.2 elevated spike discharges in sensory nerves and at the neuromuscular junction, and also caused a depolarization of the membrane potential in cockroach giant axons. All these effects were reversed by treatment with the specific sodium channel blocker, tetrodotoxin. These findings suggest that DTX9.2 acts upon the voltage-dependent sodium channels of insect nerve membrane.

This report provides an item-by-item description and explanation of the new Act, which will guide agricultural programs from 1996-2000. Signed into law in April, the act makes significant changes in long-standing U.S. agricultural policies. Major changes in U.S. commodity programs are included in the Act's Title I, known as the Agricultural Market Transition Act.

Agricultural economists are appropriately concerned about their profession's contributions to policy decisions. An examination of alternative approaches to transforming policy analyses is in order. There are opportunities to (a) focus on income and wealth distribution, (b) give attention to the public as a primary client, (c) avoid advocacy, and (d) adjust institutions in ways that encourage participation in policy analyses including the development of data systems.

Agricultural economists are appropriately concerned about their profession's contributions to policy decisions. An examination of alternative approaches to transforming policy analyses is in order. There are opportunities to (a) focus on income and wealth distribution, (b) give attention to the public as a primary client, (c) avoid advocacy, and (d) adjust institutions in ways that encourage participation in policy analyses including the development of data systems.

Magnetic data acquired over a range of lithologies show the following: the Deer Park Complex of Clew Bay exhibits different magnetic characteristics east and west of Croagh Patrick. Very large magnetic signatures (4000-8000nT) occur in the west but the anomahlies are significantly lower in the east. In addition, the peak anomaly bounds the northern edge of the Deer Park Complex in the west but the southern edge to the east Lower Palaeozoic volcanics flanking the Leinster Granite yield anomalies of 300nT with a variance of 5-30nT, whereas those in the Kildare Inlier have a variance of 20-100nT and anomalies of 700nT. The background variation in magnetism for the Northern, Upper Liffey Valley and Lugnaquillia Units of the Leinster Gramnite is 2-5nT (similar to the Lower Palaeozoic sediments into which the gramnite is intruded) and structures are associated with anomalies of 30nT. The magnetic variance within the Dalradian in County Tyrone is about 5nT and peak anomalies of around 30nT have been obtained. Structures within Tertiary basalts and gabbros produce anomalies of a similar magnitude (1000-2000nT), but the variance for the basalts (300nT) is an order of magnitude greater than the variance of the gabbros. Structures in a range of hlithologies (including Carboniferous limestone) exhibit similar magnetic patterns, though the amplitude of the peak anomaly.

Ground magnetometer traverses over drift-covered Tertiary basalt areas in north- east Ireland have revealed large-amplitude anomalies (>2000nT). Fault zones produce characteristic wide-zoned, large-variance, high-frequency anomalies, while faults that juxtapose basalts with different magnetic properties, or basalt against a non-magnetic lithology, can be identified. Plugs and relict fissures both produce large magnetic anomalies (up to 4000nT). Dykes associated with the basalts generally give anomalies of

An interview with Csaba Csaki, Rector, Budapest University of Economics.

An interview with Csaba Csaki, Rector, Budapest University of Economics.

In early February, the Administration presented its proposal for the 1990 Farm Bill. Because of its great relevance to the ensuing debate and the eventual choices made by the Congress and the Administration, we are pleased to include this interview with U.S. Secretary of Agriculture, Clayton Yeutter.

In early February, the Administration presented its proposal for the 1990 Farm Bill. Because of its great relevance to the ensuing debate and the eventual choices made by the Congress and the Administration, we are pleased to include this interview with U.S. Secretary of Agriculture, Clayton Yeutter.