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Laser-induced incandescence (LII) is a widely used technique for measuring soot concentrations. For flame applications LII is frequently deployed as a planar diagnostic to measure the two-dimensional soot field. However, when the laser sheet is focused, as is typical to reach the requisite laser fluence level and achieve good spatial resolution, the complex laser power dependence of the LII signal generation process can introduce a large variation in LII signal sensitivity across an LII image. In this work, this effect is quantified for the first time as a function of laser pulse fluence, using a typical planar LII excitation scheme with a clipped Gaussian YAG laser beam focused with a 1 m focal length lens. Furthermore, the cross-sectional energy distribution in the laser sheet was measured across the image plane, to relate the details of the laser sheet focal properties with the resultant LII behavior. The results show that a unique laser fluence level (referenced to the focal plane) exists whereby there is essentially no dependence of LII signal on position relative to the focal plane. However, at lower or higher fluences, the radial signals either decrease (low fluence) or increase (high fluence) rapidly with increasing distance away from the focal point. For measurements using an LII ‘plateau’ laser fluence level, as is usual in environments with significant optical depth (i.e. sufficiently strong soot levels), the LII signals are found to be 2.5X larger 40 mm away from the focal point. An analysis conducted by combining a previously measured LII fluence dependence for a top-hat laser profile with the laser sheet cross-sections measured in this work shows general agreement with the measured results for LII signal variation. Further, the sensitivity of LII signals at high fluences to the laser beam spatial profile, particularly away from the sheet focus, is highlighted.

Non-premixed oxy-fuel combustion of natural gas is used in industrial applications where high-intensity heat is required, such as glass manufacturing and metal forging and shaping. In these applications, the high flame temperatures achieved by oxy-fuel combustion increase radiative heat transfer to the surfaces of interest and soot formation within the flame is desired for further augmentation of radiation. However, the high cost of cryogenic air separation has limited the penetration of oxy-fuel combustion technologies. New approaches to air separation are being developed that may reduce oxygen production costs, but only for intermediate levels of oxygen enrichment of air. To determine the influence of oxygen enrichment on soot formation and radiation, we developed a non-premixed coannular burner in which oxygen concentrations and oxidizer flow rates can be independently varied, to distinguish the effects of turbulent mixing intensity from oxygen enrichment on soot formation and flame radiation. Local radiation intensities, soot concentrations, and soot temperatures have been measured using a thin-film thermopile, planar laser-induced incandescence (LII), and two-color imaging pyrometry, respectively. The measurements show that soot formation increases as the oxygen concentration decreases from 100% to 50%, helping to moderate a decrease in overall flame radiation. An increase in turbulence intensity has a marked effect on flame height, soot formation and thermal radiation, leading to decreases in all of these. The soot temperature decreases with a decrease in the oxygen concentration and increases with an increase in turbulent mixing intensity. Overall, the results suggest that properly designed oxygen-enriched burners that enhance soot formation for intermediate levels of oxygen purity may be able to achieve thermal radiation intensities as high as 85% of traditional oxy-fuel burners utilizing high-purity oxygen.

The high-resolution human leukocyte antigen (HLA) genotyping assay that we developed using 454 sequencing and Conexio software uses generic polymerase chain reaction (PCR) primers for DRB exon 2. Occasionally, we observed low abundance DRB amplicon sequences that resulted from in vitro PCR ‘crossing over’ between DRB1 and DRB3/4/5. These hybrid sequences, revealed by the clonal sequencing property of the 454 system, were generally observed at a read depth of 5%–10% of the true alleles. They usually contained at least one mismatch with the IMGT/HLA database, and consequently, were easily recognizable and did not cause a problem for HLA genotyping. Sometimes, however, these artifactual sequences matched a rare allele and the automatic genotype assignment was incorrect. These observations raised two issues: (1) could PCR conditions be modified to reduce such artifacts? and (2) could some of the rare alleles listed in the IMGT/HLA database be artifacts rather than true alleles? Because PCR crossing over occurs during late cycles of PCR, we compared DRB genotypes resulting from 28 and (our standard) 35 cycles of PCR. For all 21 cell line DNAs amplified for 35 cycles, crossover products were detected. In 33% of the cases, these hybrid sequences corresponded to named alleles. With amplification for only 28 cycles, these artifactual sequences were not detectable. To investigate whether some rare alleles in the IMGT/HLA database might be due to PCR artifacts, we analyzed four samples obtained from the investigators who submitted the sequences. In three cases, the sequences were generated from true alleles. In one case, our 454 sequencing revealed an error in the previously submitted sequence.

The human leukocyte antigen (HLA) class I and class II loci are the most polymorphic genes in the human genome; distinguishing the thousands of HLA alleles is challenging. Next generation sequencing of exonic amplicons with the 454 genome sequence (GS) FLX System and Conexio Assign ATF 454 software provides high resolution, high throughput HLA genotyping for eight class I and class II loci. HLA typing of potential donors for unrelated bone marrow donor registries typically uses a subset of these loci at high sample throughput and low cost per sample. The Fluidigm Access Array System enables the incorporation of 48 different multiplex identifiers (MIDs) corresponding to 48 genomic DNA samples with up to 48 different primer pairs in a microfluidic device generating 2304 parallel polymerase chain reactions (PCRs). Minimal volumes of reagents are used. During genomic PCR, in this 4-primer system, the outer set of primers containing the MID and the 454 adaptor sequences are incorporated into an amplicon generated by the inner HLA target-specific primers each containing a common sequence tag at the 5' end of the forward and reverse primers. Pools of the resulting amplicons are used for emulsion PCR and clonal sequencing on the 454 Life Sciences GS FLX System, followed by genotyping with Conexio software. We have genotyped 192 samples with 100% concordance to known genotypes using 8 primer pairs (covering exons 2 and 3 of HLA-A, B and C, and exon 2 of DRB1, 3/4/5 and DQB1) and 96 MIDs in a single GS FLX run. An average of 166 reads per amplicon was obtained. We have also genotyped 96 samples at high resolution (14 primer pairs covering exons 2, 3, and 4 of the class I loci and exons 2 of DRB1, 3/4/5, DQA1, DQB1, DPB1, and exon 3 of DQB1), recovering an average of 173 sequence reads per amplicon.

The implementation of safety codes and standards for hydrogen-based energy systems will require a scientific basis for evaluating credible safety issues and for developing safety codes and standards applicable to the future hydrogen infrastructure. The characterization of unintended releases from hydrogen components has been identified as an area of particular interest to codes and standards development. In the present study, measurements were performed in small-scale hydrogen leaks to characterize the dimensional properties and flow characteristics of the resulting ignitable hydrogen cloud. Specifically, the data will provide a technological basis for determining hazardous length scales associated with the formation of ignitable mixtures due to unintended releases. In contrast to previous studies where large-scale momentum-dominated releases were considered, the present study focuses on smaller-scale releases more characteristic of low-pressure electrolyzers, leaky fittings or O-rings seals where moderate pressure drops and lower flow rates might occur. A turbulent jet flow is selected as representative of releases in which the leak geometry is circular. Laser-based Rayleigh scattering is used to characterize the hydrogen concentration field downstream of the leak. Time-averaged mean and fluctuating hydrogen concentration statistics and the corresponding probability density distributions are presented and the results for a pure hydrogen jet are compared with literature data for other gases such as methane and propane. At the moderate Froude number (Fr = 268) flow condition studied, the global jet features such as H2 centerline decay, jet spreading rate, and the mean and fluctuating H2 concentration distributions are similar to other variable density jets in the momentum-dominated regime and follow similar scaling laws. The database presented should provide a good test for the validation of CFD models being developed to predict unintended hydrogen release scenarios.

Measurements were performed in small-scale hydrogen leaks to characterize the dimensional properties and flow characteristics of the resulting ignitable hydrogen cloud. The data are intended to provide a technological basis for determining hazardous length scales associated with the formation of ignitable mixtures due to unintended releases. In contrast to a previous study where momentum-dominated releases were considered, the present study focuses on smaller-scale releases at lower flow rates where buoyancy becomes important. A turbulent jet flow is selected as representative of releases in which the leak geometry is circular. Laser-based Rayleigh scattering is used to characterize the hydrogen concentration field downstream of the leak. Particle Image Velocimetry (PIV) is also used to characterize the flow velocity. Time-averaged mean and fluctuating hydrogen concentration statistics are presented and compared with results in momentum-dominated flows to elucidate the effects of buoyancy on the H 2 dispersion process. Over the range of Froude numbers investigated ( Fr = 268, 152 and 99), increasing effects of buoyancy are seen as the Fr is reduced and at downstream locations where the influence of buoyancy increases relative to jet momentum. The primary effect of buoyancy is to increase the centerline decay rate of the time-averaged H 2 mass fraction relative to momentum-dominated flows. Acceleration due to buoyancy also results in a slower decay of the time-averaged axial velocity component along the centerline. Radial profiles of the time-averaged H 2 mass fraction also collapse onto the same curves as results in momentum-dominated flows when plotted against the same similarity/scaling variables. While buoyancy is found to have a negligible effect on centerline velocity fluctuations, the maximum H 2 mass fraction fluctuation intensity increases by 70 percent in the buoyant regime and the peak value shifts from the mixing region to the jet centerline. The database presented should provide a good test for the validation of CFD models being developed to predict unintended hydrogen releases under conditions where buoyancy is important.

Future energy systems based on gasification of coal or biomass for co-production of electrical power and fuels may require gas turbine operation on unusual gaseous fuel mixtures. In addition, global climate change concerns may dictate the generation of a CO2 product stream for end-use or sequestration, with potential impacts on the oxidizer used in the gas turbine. In this study the operation at atmospheric pressure of a small, optically accessible swirl-stabilized premixed combustor, burning fuels ranging from pure methane to conventional and H2-rich and H2-lean syngas mixtures is investigated. Both air and CO2-diluted oxygen are used as oxidizers. CO and NOx emissions for these flames have been determined from the lean blowout limit to slightly rich conditions (ϕ ∼ 1.03). In practice, CO2-diluted oxygen systems will likely be operated close to stoichiometric conditions to minimize oxygen consumption while achieving acceptable NOx performance. The presence of hydrogen in the syngas fuel mixtures results ...

Measurements were performed to characterize the dimensional and radiative properties of large-scale, vertical hydrogen-jet flames. This data is relevant to the safety scenario of a sudden leak in a high-pressure hydrogen containment vessel and will provide a technological basis for determining hazardous length scales associated with unintended hydrogen releases at storage and distribution centers. Jet flames originating from high-pressure sources up to 413 bar (6000 psi) were studied to verify the application of correlations and scaling laws based on lower-pressure subsonic and choked-flow jet flames. These higher pressures are expected to be typical of the pressure ranges in future hydrogen storage vessels. At these pressures the flows exiting the jet nozzle are categorized as underexpanded jets in which the flow is choked at the jet exit. Additionally, the gas behavior departs from that of an ideal-gas and alternate formulations for non-ideal gas must be introduced. Visible flame emission was recorded on video to evaluate flame length and structure. Radiometer measurements allowed determination of the radiant heat flux characteristics. The flame length results show that lower-pressure engineering correlations, based on the Froude number and a non-dimensional flame length, also apply to releases up to 413 bar (6000 psi). Similarly, radiative heat flux characteristics of these high-pressure jet flames obey scaling laws developed for low-pressure, smaller-scale flames and a wide variety of fuels. The results verify that such correlations can be used to a priori predict dimensional characteristics and radiative heat flux from a wide variety of hydrogen-jet flames resulting from accidental releases.

The flame structure of laminar inverse diffusion flames (IDFs) was studied to gain insight into soot formation and growth in underventilated combustion. Both ethylene–air and methane–air IDFs were examined, fuel flow rates were kept constant for all flames of each fuel type, and airflow rates were varied to observe the effect on flame structure and soot formation. Planar laser-induced fluorescence of hydroxyl radicals (OH PLIF) and polycyclic aromatic hydrocarbons (PAH PLIF), planar laser-induced incandescence of soot (soot PLII), and thermocouple-determined gas temperatures were used to draw conclusions about flame structure and soot formation. Flickering, caused by buoyancy-induced vortices, was evident above and outside the flames. The distances between the OH, PAH, and soot zones were similar in IDFs and normal diffusion flames (NDFs), but the locations of those zones were inverted in IDFs relative to NDFs. Peak OH PLIF coincided with peak temperature and marked the flame front. Soot appeared outside the flame front, corresponding to temperatures around the minimum soot formation temperature of 1300 K. PAHs appeared outside the soot layer, with characteristic temperature depending on the wavelength detection band. PAHs and soot began to appear at a constant axial position for each fuel, independent of the rate of air flow. PAH formation either preceded or coincided with soot formation, indicating that PAHs are important components in soot formation. Soot growth continued for some time downstream of the flame, at temperatures below the inception temperature, probably through reaction with PAHs.

In a study on syngas combustion in a swirl-stabilized combustor, red deposits quickly formed on the quartz combustor walls, preventing laser diagnostic measurements. Analysis of the deposit showed that is was composed of iron and nickel. A literature review revealed that typical pressurized cylinders of CO, even at the highest CO purity level, contain up to 100 ppmv of iron pentacarbonyl and somewhat smaller levels of nickel tetracarbonyl. Only semiconductor grade CO stored in aluminum cylinders has sub-ppm levels of carbonyls. The demonstrated strong flame inhibition effect of carbonyls suggests that the use of CO from steel cylinders in combustion experiments may affect studies of flame ignition or extinction, in addition to the effect of particle formation and deposition observed here.

The dimensionless extinction coefficient ( K e ) of soot must be known to quantify laser extinction measurements of soot concentration and to predict optical attenuation through smoke clouds. Previous investigations have measured K e for post-flame soot emitted from laminar and turbulent diffusion flames and smoking laminar premixed flames. This paper presents the first measurements of soot K e from within laminar diffusion flames, using a small extractive probe to withdraw the soot from the flame. To measure K e, two laser sources (635 nm and 1310 nm) were coupled to a transmission cell, followed by gravimetric sampling. Coannular diffusion flames of methane, ethylene and nitrogen-diluted kerosene burning in air were studied, together with slot flames of methane and ethylene. K e was measured at the radial location of maximum soot volume fraction at several heights for each flame. Results for K e at both 635 nm and 1310 nm for ethylene and kerosene coannular flames were in the range of 9–10, consistent with the results from previous studies of post-flame soot. The ethylene slot flame and the methane flames have lower K e values, in some cases as low as 2.0. These lower values of K e are found to result from the contributions of (a) the condensation of PAH species during the sampling of soot, (b) the wavelength-dependent absorptivity of soot precursor particles, and, in the case of methane, (c) the negligible contribution of soot scattering to the extinction coefficient. RDG calculations of soot scattering, in combination with the measured K e values, imply that the soot refractive index is in the vicinity of 1.75–1.03 i at 635 nm.

Oxy-fuel combustion is a well-known approach to improve the heat transfer associated with stationary energy processes. Its overall penetration into industrial and power markets is constrained by the high cost of existing air separation technologies for generating oxygen. Cryogenic air separation is the most widely used technology for generating oxygen but is complex and expensive. Pressure swing adsorption is a competing technology that uses activated carbon, zeolites and polymer membranes for gas separations. However, it is expensive and limited to moderate purity O₂ . MOFs are cutting edge materials for gas separations at ambient pressure and room temperature, potentially revolutionizing the PSA process and providing dramatic process efficiency improvements through oxy-fuel combustion. This LDRD combined (1) MOF synthesis, (2) gas sorption testing, (3) MD simulations and crystallography of gas siting in pores for structure-property relationship, (4) combustion testing and (5) technoeconomic analysis to aid in real-world implementation.

In turbulent buoyant fire plumes, local inverse diffusion flames of air injected into gaseous fuel or fuel vapors occur, but little is known about the tendency to form soot and produce thermal radiation in these flame structures. To investigate these phenomena, steady and pulsed normal and inverse jet diffusion flames of methane/air and ethylene/air have been stabilized on a slot burner, which has advantages over a coannular flame geometry for performing flame imaging measurements in sooty flames. OH and PAH laser-induced fluorescence (LIF), soot laser-induced incandescence (LII), and soot thermal emission at 850 nm have been measured in the lower flame region of steady and pulsed flames. These measurements reveal that the relative positions of these different structural features are very similar in the normal and inverse steady flames of each fuel. Also, the OH signals are nearly identical in the normal and inverse flames. The inverse flame PAH signals and soot concentrations are somewhat smaller than for the normal flames, and the near-infrared radiation is approximately 25% lower for the inverse flame. When the central slot is pulsed, the primary buoyant vortex roll-up occurs on the fuel-rich side of inverse flames, resulting in strongly enhanced PAH signals and soot concentrations. The near-infrared radiation also increases in the pulsed flames, but not from the soot within the vortex roll-up region. In general, enhancements in peak signals from soot and near-infrared radiation similar to those in pulsed normal diffusion flames are apparent in pulsed inverse diffusion flames. PAH signals are clearly greatest in the pulsed inverse flames.

Autumnal migration was studied with high-resolution radar, ceilometer, and daily census in the area of Franconia Notch, a major pass in the northern Appalachian Mountains. Under synoptic conditions favorable for migration, broadfront movements of migrants toward the south passed over the mountains, often above a temperature inversion. Birds at lower elevations appeared to be influenced by local topography. Birds moving southwest were concentrated along the face of the mountain range. Birds appeared to deviate their flights to follow local topography through the pass. Specific migratory behavior was not associated with species or species groups. Under synoptic conditions unfavorable for southward migration, multimodal movements probably associated with local flights were as dense as the southward migrations described above. Avian migrants reacting to local terrain may result in concentrations of migrants over ridge summits or other topographic features.

Intensified charge-coupled devices (ICCDs) are used extensively in many scientific and engineering environments to image weak or temporally short optical events. To optimize the quantum efficiency of light collection, many of these devices are chosen to have characteristic intensifier gate times that are relatively slow, on the order of tens of nanoseconds. For many measurements associated with nanosecond laser sources, such as scattering-based diagnostics and most laser-induced fluorescence applications, the signals rise and decay sufficiently fast during and after the laser pulse that the intensifier gate may be set to close after the cessation of the signal and still effectively reject interferences associated with longer time scales. However, the relatively long time scale and complex temporal response of laser-induced incandescence (LII) of nanometer-sized particles (such as soot) offer a difficult challenge to the use of slow-gating ICCDs for quantitative measurements. In this paper, ultraviolet Rayleigh scattering imaging is used to quantify the irising effect of a slow-gating scientific ICCD camera, and an analysis is conducted of LII image data collected with this camera as a function of intensifier gate width. The results demonstrate that relatively prompt LII detection, generally desirable to minimize the influences of particle size and local gas pressure and temperature on measurements of the soot volume fraction, is strongly influenced by the irising effect of slow-gating ICCDs.

Na(+)-dependent nucleoside transport was examined in bovine renal brush-border membrane vesicles. Two separate Na+/nucleoside cotransporters were shown to be present: (1) a system specific for purine nucleosides and uridine, designated as the N1 carrier, and (2) an Na(+)-dependent nucleoside transporter that accepts pyrimidine nucleosides, adenosine and analogues of adenosine, designated as the N2 system. Both systems exhibit a high affinity for nucleosides (apparent Km values approximately 10 microM), are insensitive to inhibition by facilitated-diffusion nucleoside transport inhibitors, are rheogenic and exhibit a high specificity for Na+. Na+ increases the affinity of the influx of guanosine and thymidine, nucleosides that serve as model permeants for the N1 and N2 nucleoside transporters respectively. The Na+/nucleoside coupling stoichiometry is consistent with 1:1 for both carriers.

Intensified charge-coupled devices (ICCDs) are used extensively in many scientific and engineering environments to image weak or temporally short optical events. Care has to be taken in interpreting the images from ICCDs if quantitative results are required. In particular, nonuniform gain (flat field) and nonlinear response effects must be properly accounted for. Traditional flat-field corrections can only be applied in the linear regime of the ICCD camera, which limits the usable dynamic range. This paper reports a more general approach to image correction whereby the nonlinear gain response of each pixel of the ICCD is characterized over the full dynamic range of the camera. Image data can then be corrected for the combined effects of nonuniform gain and nonlinearity. The results from a two-color pyrometry measurement of soot field temperature are used to illustrate the capabilities of the new correction approach.

Planar Laser Induced Fluorescence (PLIF) measurements of the hydroxyl radical in lean, premixed natural gas flames augmented with hydrogen are presented. The experiments were conducted in the SimVal combustor at the National Energy Technology Laboratory (NETL) at operating pressures from 1 to 8 atmospheres. The data, which was collected in a combustor with well controlled boundary conditions, is intended to be used for validating Computational Fluid Dynamics (CFD) models under conditions directly relevant to land-based gas turbine engines. The images, which show significant effects of hydrogen on local flame quenching are discussed in terms of a turbulent premixed combustion regime and non-dimensional parameters such as Karlovitz number. Pressure was found to thin the OH region, but only had a secondary effect on overall flame shape compared to the effects of hydrogen addition which was found to decrease local quenching and shorten the turbulent flame brush. A method to process the individual images based on local gradients of fluorescence intensity is proposed and results are presented. Finally, the results of several Large Eddy Simulations (LES) are presented and compared to the experimental data in an effort to understand the issues related to model validation, especially for simulations that do not includemore » OH as an intermediate species.« less

Future energy systems based on solid fuel gasification for co-production of power and fuels may require gas turbine operation on unusual gas fuel mixtures. In addition, global climate change concerns may dictate the production of a CO2 product stream for end-use or sequestration, with potential impacts on the oxidizer used in the gas turbine. In this study the operation at atmospheric pressure of a small, optically accessible swirl-stabilized premixed combustor is investigated when burning fuels ranging from pure methane to shifted or filtered syngas mixtures. Both air and CO2 -diluted oxygen are used as oxidizers. CO and NOx emissions for these flames have been determined over the full operation range from lean blowout to slightly rich conditions. In practice, CO2 -diluted oxygen systems will likely be operated close to stoichiometric conditions to minimize oxygen consumption. The presence of hydrogen in the syngas fuel mixtures results in compact, high temperature flames, resulting in increased flame stability and higher NOx emissions. The lean blowout limit decreases with increasing H2 content in the syngas. Similarly, CO emissions for lean stoichiometries decrease with increasing H2 content. CO emissions near the stoichiometric combustion point do not become significant until φ > 0.95, at which point CO emissions rise more rapidly for combustion in O2 -CO2 mixtures than for combustion in air.Copyright © 2007 by ASME

Flame heights of co-flowing cylindrical ethylene-air and methane-air laminar inverse diffusion flames were measured. The luminous flame height was found to be longer than the height of the reaction zone determined by planar laser-induced fluorescence (PLIF) of hydroxyl radicals (OH) because of luminous soot above the reaction zone. However, the location of the peak luminous signals along the centerline agreed very well with the OH flame height. Flame height predictions using Roper’s analysis for circular port burners agreed with measured reaction zone heights when using values for the characteristic diffusion coefficient and/or diffusion temperature somewhat different from those recommended by Roper. The fact that Roper’s analysis applies to inverse diffusion flames is evidence that inverse diffusion flames are similar in structure to normal diffusion flames.

Fires pose the dominant risk to the safety and security of nuclear weapons, nuclear transport containers, and DOE and DoD facilities. The thermal hazard from these fires primarily results from radiant emission from high-temperature flame soot. Therefore, it is necessary to understand the local transport and chemical phenomena that determine the distributions of soot concentration, optical properties, and temperature in order to develop and validate constitutive models for large-scale, high-fidelity fire simulations. This report summarizes the findings of a Laboratory Directed Research and Development (LDRD) project devoted to obtaining the critical experimental information needed to develop such constitutive models. A combination of laser diagnostics and extractive measurement techniques have been employed in both steady and pulsed laminar diffusion flames of methane, ethylene, and JP-8 surrogate burning in air. For methane and ethylene, both slot and coannular flame geometries were investigated, as well as normal and inverse diffusion flame geometries. For the JP-8 surrogate, coannular normal diffusion flames were investigated. Soot concentrations, polycyclic aromatic hydrocarbon (PAH) laser-induced fluorescence (LIF) signals, hydroxyl radical (OH) LIF, acetylene and water vapor concentrations, soot zone temperatures, and the velocity field were all successfully measured in both steady and unsteady versions of these various flames. Inmore » addition, measurements were made of the soot microstructure, soot dimensionless extinction coefficient (&), and the local radiant heat flux. Taken together, these measurements comprise a unique, extensive database for future development and validation of models of soot formation, transport, and radiation.« less

Aim To investigate the origin of an extremely high AT1r result in a 0% PRA pediatric kidney recipient and history of nonspecific positive flow crossmatch. Methods Pt was HLA typed by rSSOP and 0% PRA was documented by LABScreen Single Antigen Assay (OL). Patient’s serum (P’s.S) was tested with AT1r ELISA (OL). The identical solid phase plate Maxisorp (Nunc) without the AT1r antigen was incubated with P’s.S and the kit Negative Control (NC). The plate was also treated with casein (Sigma) and BSA (Thermo Fisher), two reagents commonly used to block nonspecific reactions. A human serum (HS) sample with a negative AT1r reaction was used as a different source of protein. The secondary anti-IgG antibody conjugated with HRP and TMB from the AT1r kit was used to complete the reaction. Results Serum from a pediatric Pt with history of nonspecific flow crossmatch was used as part of the AT1r assay validation in our lab. Results with the undiluted serum were outside of the range as defined by the calibrator curve. Serial dilutions obtained an OD = 2034 and a concentration of 58.72 U/ml at titer 1:2048. The Pt was transplanted October 2013 with Thymo induction without any complications and maintains an excellent kidney graft function at the time of this abstract. With a history of no sensitization events and the graft outcome we suspect a nonspecific AT1r reaction. The P’s.S was incubated in an untreated plate to evaluate a positive reactivity against the polystyrene surface. We obtained an OD = 56 below the OD of the NC. When the P’s.S was added to the plate blocked with 0.5% casein in PBS the result was: P’s.S-OD = 3617/NC-OD = 43. The reading in the well blocked with 0.5% BSA in PBS was: P’s.S OD = 3071/NC-OD = 39. The reaction with the plate treated with HS (Neg: AT1r) was: P’s.S OD = 811/NC-OD = 777, both values are elevated but significantly lower than the well treated with the casein or BSA. Conclusions The lack of sensitization events, a favorable graft outcome, and these results lead us to believe that nonspecific reactions are to blame with regards to P’s.S reacting with the AT1r kit. Negative OD values with the untreated surface or treated with a HS versus high OD values with the surface treated with casein and BSA suggest a reaction against a protein of bovine origin present in the kit components. Further work will be needed to demonstrate this observation.

Aim Next generation sequencing of HLA exonic amplicons with the 454 Life Sciences GS FLX System and Conexio Assign TM -ATF software provides high resolution, high throughput HLA genotyping for 8 class I and class II loci (Bentley et al., 2009 1 , Holcomb et al., 2011 2 ). HLA typing of potential donors for Unrelated Bone Marrow Donor Registries requires using a subset of these loci at high sample throughput and low cost per sample. To maximize the throughput, we have incorporated the Fluidigm ® Access Array TM system to simplify amplicon library preparation and allow the efficient introduction of MIDs (Multiplex Identifiers) or barcodes. Methods For this application, a streamlined amplicon sequencing workflow employing many different Multiplex Identifiers (MIDs) enables multiplexed sequencing of a large number of samples, allowing researchers to meet these cost targets. The Fluidigm ® 48 x 48 Access Array TM system and the “4 primer” approach provides an efficient way to achieve parallel semi-automated genomic PCRs with simultaneous incorporation of 48 different MIDs corresponding to 48 genomic DNA samples, and up to 48 different primer pairs, making possible 2,304 reactions in one amplification run. Minimal volumes (calculated to be about 45% less cost per run) of reagents are used in this micro- fluidics-based system. During genomic PCR, the outer set of primers containing the MIDs and the 454 adaptor sequences are incorporated into the amplicons generated by the inner set of HLA specific primers containing a complementary “universal” Fluidigm tag. Pools of the resulting amplicons are used for emulsion PCR and clonal sequencing on the 454 GS FLX System, as well as genotyping with Conexio Assign TM -ATF software. Results Using the Access Array system, we have successfully (100% concordance with known genotypes) genotyped 192 samples with 8 primer pairs (covering exons 2 and 3 in HLA-A, B, C and Exon 2 in DRB1, DRB3/4/5 and DQB1) using 96 MIDs per region in a single GS FLX run on a 2 region PicoTiterPlate™ (PTP) and 96 samples using 48 MIDs per region in a 4 region PTP. An average of 166 and 137 sequence reads per amplicon were recovered respectively. We have also genotyped, in a single run, 96 samples at high resolution (14 primer pairs covering exons 2, 3, and 4 of the class I loci and exons 2 of DRB1,3/4/5, DQA1, DQB1, DPB1, and exon 3 of DQB1) recovering an average of 175 sequence reads per amplicon at 100% concordance. The system reduces the overall time for the entire process (192 samples) from 8 days for manual processing to about 4 days with 1 FTE.

Mutations in the estrogen-receptor gene have been thought to be lethal. A 28-year-old man whose estrogen resistance was caused by a disruptive mutation in the estrogen-receptor gene underwent studies of pituitary-gonadal function and bone density and received transdermal estrogen for six months. Estrogen-receptor DNA, extracted from lymphocytes, was evaluated by analysis of single-strand-conformation polymorphisms and by direct sequencing.The patient was tall (204 cm [80.3 in.]) and had incomplete epiphyseal closure, with a history of continued linear growth into adulthood despite otherwise normal pubertal development. He was normally masculinized and had bilateral axillary acanthosis nigricans. Serum estradiol and estrone concentrations were elevated, and serum testosterone concentrations were normal. Serum follicle-stimulating hormone and luteinizing hormone concentrations were increased. Glucose tolerance was impaired, and hyperinsulinemia was present. The bone mineral density of the lumbar spine was 0.745 g per square centimeter, 3.1 SD below the mean for age-matched normal women; there was biochemical evidence of increased bone turnover. The patient had no detectable response to estrogen administration, despite a 10-fold increase in the serum free estradiol concentration. Conformation analysis of his estrogen-receptor gene revealed a variant banding pattern in exon 2. Direct sequencing of exon 2 revealed a cytosine-to-thymine transition at codon 157 of both alleles, resulting in a premature stop codon. The patient's parents were heterozygous carriers of this mutation, and pedigree analysis revealed consanguinity.Disruption of the estrogen receptor in humans need not be lethal. Estrogen is important for bone maturation and mineralization in men as well as women.

This paper details the design of a premixed, swirl-stabilized combustor that was designed and built for the express purpose of obtaining validation-quality data for the development of large eddy simulations (LES) of gas turbine combustors. The combustor features nonambiguous boundary conditions, a geometrically simple design that retains the essential fluid dynamics and thermochemical processes that occur in actual gas turbine combustors, and unrestrictive access for laser and optical diagnostic measurements. After discussing the design detail, a preliminary investigation of the performance and operating envelope of the combustor is presented. With the combustor operating on premixed methane/air, both the equivalence ratio and the inlet velocity were systematically varied and the flame structure was recorded via digital photography. Interesting lean flame blowout and resonance characteristics were observed. In addition, the combustor exhibited a large region of stable, acoustically clean combustion that is suitable for preliminary validation of LES models.

Both search and height-finding radars were used to observe the airborne behavior of free-tailed bats, Tadarida brasiliensis mexicana , near several caves in the southwestern United States. Radar echoes from dense groups of bats covered areas as large as 400 square kilometers and rose to altitudes of more than 3000 meters. The presence of large numbers of bats within these areas was confirmed by visual observation from a helicopter. Bat flights appeared on radar at dusk and at dawn as a slowly expanding or contracting target, usually located near a known roost. The direction in which the echo expanded most rapidly was not due to drift of the bats by winds. This leading edge often moved at more than 40 kilometers per hour, indicating the capacity for rapid, well-directed, high altitude flight in these animals. Bats flying at such high altitudes must employ sensory systems other than echolocation for orientation and navigation.

Several species of shorebirds migrate between eastern Asia and the southern Pacific islands, Australia, and New Zealand. Observations made from Guam (13?25'N, 144?45'E) during autumn 1983 indicate that a significant number of birds take a direct route over the western Pacific Ocean. Radar observations and ground counts of migrants on Guam showed two periods of autumnal migratory activity. The first, largely adult birds, was in August and September. The second, largely juveniles, was in late September and October. Radar indicated that large numbers of birds passed over the island to the south with no evidence of compensation for drift by the easterly winds. Comparison of radar and ground observations on Guam showed that only a small subset of migrants stop on the island, suggesting that some species may make nonstop flights between eastern Asia and the South Pacific. Received 3 August 1987, accepted 22 February 1988. ORNITHOLOGISTS in Europe and North America can draw on more than a century of migration studies using bird banding and on 40 years of radar observations. The study of migration patterns from Asia to Australia and the South Pacific is comparatively recent. McClure (1974) reviewed autumn banding records of several species of shorebirds (Charadriiformes) from southeast Asia, the Philippines, eastern China, and Japan. The movement was primarily southwest along the mainland coast to southeast Asia and the Philippines, with a few recoveries as far south as Australia. Weishu and Purchase (1983) reviewed the preliminary results of the Australian Bird Banding Scheme and reported several recoveries of northbound shorebird migrants to China from Australia but no recoveries of southbound birds returning to Australia. These data suggest a southward movement over open water rather than along a coastal route. Reviews of the distribution of shorebirds indicate that several species migrate between eastern Asia and Micronesia (Baker 1951; Owen 1977; Pyle and Engbring 1985, 1987), Australia (Lane 1987), and New Zealand (Davies 1986, Sagar 1986). In the western Pacific islands the primary migrant shorebirds are Lesser Golden-Plovers (Pluvialis dominica fulva) and Ruddy Turnstones (Arenaria interpres) (Bell 1948; Johnson 1973, 1979; Smart 1973; Thompson 1973; Jenkins 1981; Schipper 1985; Pyle and Engbring 1985; Williams and Grout 1985; Hayes 1986). Nonshorebird migrants to Micronesia are rare, with the exception of the Cattle Egret (Bubulcus ibis) (Pyle and Engbring 1985, 1987; Williams and Grout 1985). We conclude from these studies that significant numbers of Lesser Golden-Plovers and Ruddy Turnstones, as well as smaller numbers of other shorebirds, including both tattler species (Heteroscelus incanus and H. brevipes), migrate annually from northern breeding grounds to small islands and atolls in the western and southern Pacific. Bar-tailed Godwits (Limosa lapponica) and Red Knots (Calidris canutus) also make regular migrations in large numbers from breeding grounds in northern and eastern Asia to New Zealand. These species and the Great Knot (C. tenuirostris), Rufous-necked Stint (C. ruficollis), Sharp-tailed Sandpiper (C. acuminata), and Curlew Sandpiper (C. ferruginea) make regular annual migrations to Australia. There is insufficient evidence at present to determine whether their flights are primarily over southeast Asia or whether they take a more direct route over the western Pacific. Migrants not regularly seen in Micronesia may make a long, nonstop flight passing over the islands, as suggested for the Hudsonian Godwit (Limosa haemastica) in the Atlantic (Hager 1966). The Great Knot is large enough to fly nonstop between the north coast of Australia and Shanghai, a distance of 5,500 km (Barter 1986). Southward migratory activity of shorebirds in Micronesia commences in early to mid-August and continues through October, with two peak periods of arrivals. This migratory pattern 460 The Auk 105: 460-466. July 1988 This content downloaded from 207.46.13.52 on Fri, 21 Oct 2016 05:50:54 UTC All use subject to http://about.jstor.org/terms July 1988] Shorebird Migration over Guam 461 is similar to that on Hawaii, where most adult Lesser Golden-Plovers arrive in late August and either remain as residents during the nonbreeding ("winter") season or resume migration to more southerly islands throughout the Pacific. Juveniles arrive in Hawaii in late September and October (Johnson et al. 1981, Johnson and Johnson 1983). A similar 4-6 week time lapse occurs between adult and juvenile Ruddy Turnstones passing through the Pribilof Islands on their southward migration (Thompson 1973). Southward movements over the western Pacific are comparable to southward migrations over the western North Atlantic Ocean (Williams et al. 1977, Richardson 1980, Williams 1985). This nonstop overwater flight significantly shortens the route from eastern North America to South America and makes use of prevailing wind patterns to assist the flight. If the patterns of migration in the western Atlantic are determined primarily by geography and wind patterns, we would predict similar migration routes for the western Pacific where a direct overwater crossing offers similar advantages. Guam, located in the Mariana Islands 130 north of the equator and about 3,000 km from the Asian mainland, offered a location well suited to test this prediction. Comparisons of radar observations with counts of birds on the ground at continental sites often report poor agreement on the density of migration (Eastwood 1967, Williams et al. 1981). The poor correlation might be due either to groups of birds flying over large areas of a continent without landing or to the observers' inability to survey systematically a significant part of a continental area. Such comparisons gave good agreement at Maui, Hawaii, where a significant proportion of the island habitat could be surveyed and the island was a terminus of migration (Kloeckner et al. 1982). Observations on Guam offered an opportunity to test whether the correlations on Maui were due to the better survey conditions on isolated islands or to the fact that most migrants in the area landed on the island. MATERIALS AND METHODS Visual observations were made daily from 16 August through 22 October 1983 at Dungcas Beach on Guam, Mariana Islands (13?25'N, 144?45'E) as close as possible to 23 cm above mean low water on a rising tide (Fig. 1). Two observers counted shorebirds on the D

Two hypotheses for the orientation of autumnal migration over the western North Atlantic Ocean, proposed by Williams and Richardson, were tested by simulating the flight of birds from North to South America through calculated wind fields in the western North Atlantic Ocean. Use of a constant compass heading proved to be a tenable strategy for birds departing from the North American coast as far north as Nova Scotia. The range of successful headings, however, became increasingly restricted at northern latitudes. Airspeed, heading, altitude, and point of departure all had major effects on migratory success. Time required for successful non-stop migration was found to lie between 70 and 100 h for passerines and 40 to 60 h for shorebirds.

The transport of uridine into rabbit renal outer-cortical brush-border and basolateral membrane vesicles was compared at 22 degrees C. Uridine was taken up into an osmotically active space in the absence of metabolism for both types of membrane vesicles. Uridine influx by brush-border membrane vesicles was stimulated by Na+, and in the presence of inwardly directed gradients of Na+ a transient overshoot phenomenon was observed, indicating active transport. Kinetic analysis of the saturable Na+-dependent component of uridine flux indicated that it was consistent with Michaelis-Menten kinetics (Km 12 +/- 3 microM, Vmax. 3.9 +/- 0.9 pmol/s per mg of protein). The sodium:uridine coupling stoichiometry was found to be consistent with 1:1 and involved the net transfer of positive charge. In contrast, uridine influx by basolateral membrane vesicles was not dependent on the cation present and was inhibited by nitrobenzylthioinosine (NBMPR). NBMPR-sensitive uridine transport was saturable (Km 137 +/- 20 microM, Vmax. 5.2 +/- 0.6 pmol/s per mg of protein). Inhibition of uridine flux by NBMPR was associated with high-affinity binding of NBMPR to the basolateral membrane (Kd 0.74 +/- 0.46 nM). Binding of NBMPR to these sites was competitively blocked by adenosine and uridine. These results indicate that uridine crosses the brush-border surface of rabbit proximal renal tubule cells by Na+-dependent pathways, but permeates the basolateral surface by NBMPR-sensitive facilitated-diffusion carriers.

Growth hormone (GH) previously was available in limited supply and only for the treatment of GH-deficient children. The recent production of GH by recombinant DNA technology has provided a potential surfeit of this hormone and raises the possibility of its use in other conditions. In addition, the isolation, characterization, and synthesis of GH-releasing hormone (GRH) provides an opportunity to use this peptide in conditions in which increased circulating levels of GH are desired. Both GH and GRH have potential therapeutic uses in conditions other than growth retardation.

For more than two decades radar has been used to observe autumnal bird migration over the western North Atlantic Ocean and the Caribbean Sea (see Richardson 1980). Richardson (1976) used search radars to observe from the island of Puerto Rico from mid-August to early or mid-November, 1970 and 1971. Williams et al. (1977) made simultaneous short-term observations with a network of radars on the windward islands of Antigua, Tobago, and Barbados during each October from 1970 to 1973. Radar observations obtained over Antigua from 20 August to 30 September 1978 provided coverage of the fall migratory season comparable to that obtained at Puerto Rico. All data from the windward islands have been rescored and reanalyzed. The results presented here revealed an error in our previously published results and allow the development of a more unified theory of autumnal migratory behavior of birds in the Caribbean area. The FPQ-6, a long-range tracking radar (5-cm wavelength, 3-MW peak power, 0.40 beam width at 3 db points), was used on Antigua in 1970 and 1971, and the RC-32-B, a meteorological radar (10-cm wavelength, 500-kW peak power, 1.9? beam width), was used on Antigua-in 1972, 1973, and 1978 and Tobago and Barbados in 1973. Additional information on the radars may be found in Williams et al. (1977). Data were recorded from the radar Plan Position Indicator (PPI) screens on Polaroid type 107 film. In time exposures of 3-10 min slowly moving targets, such as birds, produced streaks on the film that were used to determine the direction, speed of movement, and density of migrants as described in Gauthreaux (1970) or Williams and Williams (1972). During the last minute of exposure the camera shutter was closed for 30 s and then reopened, producing a dot at the leading end of each complete track. Altitude was computed from range, angle of elevation, and correction factors for curvature of the earth and index of refraction of the atmosphere. Density of migration was determined from the maximum density observed in any PPI photograph during a 1-h period. Light, moderate, and heavy migrations were arbitrarily defined as fewer than 10 echoes in 4 min, 1020 echoes, and more than 20 echoes. Winds aloft were measured by radiosondes launched within 5 km of the radar sites, except at Tobago where the radiosonde site is located 40 km to the southwest. In almost all cases these wind data were measured within 4 h of our radar observations. Radars in the Caribbean usually operate from 0800 to 1600 local time (1200-2000 GMT). In 1978, our final observation at Antigua was at 2200 GMT daily. At all sites observations occasionally were interrupted by equipment failures or other projects with higher priority. These interruptions are shown in Fig. 1. Within the limitations of the work schedules at the radars, we obtained three observation periods/day with two or more photographs at different angles of elevation / observation period. The methods of analysis used here differ in several important respects from those used by Hilditch et al. (1973) and Williams et al. (1977). To insure uniform treatment for different years, I rescored all the original PPI photographs and rejected all tracks that could not be scored accurately for speed and altitude even if direction was unambiguous. This criterion may bias the data against small birds and those flying singly. The resulting data set of more than 2,000 tracks was used for all analyses unless otherwise indicated in the text. All statistical tests and correlations were calculated with individual tracks, not daily means. Track and ground speed refer to the velocity of a bird relative to the ground. Heading and airspeed refer to the velocity of the bird relative to the air mass and are calculated from track and ground speed by vector addition of the negative velocity of the wind measured at the altitude of the bird. Radar data show that autumnal migration over the island occurred as early as late August, with peaks in early September and again in October (Fig. 1). The heaviest migrations occurred in mid-October. Averaging tracks/observation over several years obscured the peak numbers observed during individual years. Heavy migrations in October commonly produced photographs with more than 40 complete tracks and at least 20 incomplete tracks. No photograph taken before October exceeded 14 complete tracks. Mean track by day varied from 1270 to 2070 with mean heading by day showing much less variation (128?1660). Neither tracks nor headings were significantly (P > 0.05) correlated with date. I divided migrants into two groups, those observed before 15 September (early) and those observed after 20 September (late). There were no moderate or heavy migrations between those dates. Observations of the departure of migrants from North America (Drury and Nisbet 1964; Nisbet 1970; Williams et al. 1977; Richardson 1979, 1980) and ground observations in the Caribbean (McCandless 1961, Richardson 1976, Holland and Williams 1978) suggest this division corresponds to the peak migrations of shorebirds (early) and wood warblers (late). Histograms of the distributions of observed tracks

The effects of insulin- and proinsulin-induced hypoglycemia on pituitary hormone and catecholamine secretion were compared in normal men to search for possible hypothalamic or pituitary inhibitory effects of proinsulin on glucocounterregulatory responses. When subjects received 0.1 U/kg i. v. human insulin and 25–38 μg/kg i.v. human proinsulin on separate occasions, plasma glucose decreased more rapidly after insulin, and the nadir was slightly lower, but integrated hypoglycemic responses were similar. Cortisol, growth hormone (GH), prolactin, epinephrine, and norepinephrine responses occurred more rapidly after insulin than after proinsulin. Peak and integrated cortisol, GH, and catecholamine responses to insulin and proinsulin were similar, but those of prolactin were reduced after proinsulin when compared with insulin by 42% (P < .01) and 34% (P < .05), respectively. When euglycemia was maintained by a variable glucose infusion rate after the injection of insulin and proinsulin, no differences were observed in plasma levels of any of the hormones. The intravenous injection of a dose of proinsulin (6 μg/kg), which did not produce hypoglycemia but was the molar equivalent of insulin used in the first protocol, failed to modify the GH or prolactin responses to a combined injection of GH-releasing hormone (1 μg/kg) and thyrotropin-releasing hormone (500 (xg). Our results indicate that the onset of pituitary hormone and catecholamine responses to hypoglycemia are related to the rate of plasma glucose decline, with the slower responses to proinsulin reflecting a more gradual onset of hypoglycemia. The magnitude of the cortisol, GH, and catecholamine responses, however, was comparable with proinsulin- and insulin-induced hypoglycemia. In contrast, the reduced peak and integrated prolactin responses to proinsulin imply that proinsulin-induced hypoglycemia is a submaximal stimulus for prolactin secretion or that proinsulin inhibits prolactin secretion at the hypothalamic level.

Summary o 1. The neotropical bat Phyllostomus hastatus studied in Trinidad, West Indies, showed a superior homing performance to any previously reported for bats of temperate latitudes. In one night 94 per cent of seventy-four returned from 3 to 6 miles, 57 per cent of 257 from 7 to 21 miles, and 26 per cent of 112 at 25–33 miles. None of fifty returned the first night from 39 to 40 miles, but 12 per cent were observed over the next several days. 2. On one occasion two out of five bats returned from 6 miles within 1 hr and after some releases at 15–20 miles 40 per cent of the bats returned within 3–4 hr. The homing performance was not significantly affected by intervening mountains of 2000–3000 ft or by up to 10 miles of open water. Bats released 1 mile apart homed as well or better than those released in groups. 3. Blindfolded P. hastatus flew normally and appeared to live normal lives for several days. From distances of 5–8 miles a considerable number of blindfolded bats homed during the first night. The data do not suffice to demonstrate whether or not there was a significant difference in homing performance from these distances between blindfolded bats and controls equipped with goggles similar to the blindfolds except for clear plastic windows over the eyes. But at 15 to 20 miles none of thirty-six blindfolded bats returned in one night with their eyes effectively covered, even though half those equipped with goggles did so. 4. It thus seems likely that within familiar territory these bats can find their way without the need for vision, but that at 15–20 miles they are severely handicapped if deprived of visual orientation. One simple explanation would be use of the northern range of mountains for visual piloting.

We compared the ability of SRIH and SRIH analog, SMS 201-995 (SMS), to inhibit stimulated GH and TSH secretion in men who received 120-min iv infusions of saline, SRIH (5, 50, and 500 micrograms/h), and SMS (3, 30, and 300 ng/kg.h) together with a bolus iv injection of GHRH (1 microgram/kg) and TRH (500 micrograms). Integrated GH secretion during the 60 min after GHRH plus TRH injection was decreased compared to that after saline by (mean +/- SE) 32 +/- 14% (P = 0.059), 78 +/- 5% (P less than 0.001), and 88 +/- 3% (P less than 0.001) during the 5, 50, and 500 micrograms/h SRIH infusions, and by 13 +/- 7% (P = NS), 50 +/- 15% (P less than 0.05), and 80 +/- 6% (P less than 0.001) during the 3, 30, and 300 ng/kg.h SMS infusions. In contrast, integrated TSH secretion was unaltered during the 5 micrograms/h SRIH and 3 ng/kg.h SMS infusions; it decreased by only 43 +/- 5% (P less than 0.001) and 66 +/- 4% (P less than 0.001) during the 50 and 500 micrograms/h SRIH infusions and by 33 +/- 8% (P less than 0.05) and 50 +/- 3% (P less than 0.001) during the 30 and 300 ng/kg.h SMS infusions. Analysis of the dose-response curves indicated approximately 10- and 5-fold greater potencies of SRIH and SMS, respectively, in inhibiting GH as compared to TSH secretion. These results quantify the effect of SRIH as an inhibitor of GH secretion and suggest that if SRIH has a physiological role in the inhibition of TSH secretion in man, it is limited to conditions associated with marked suppression of GH.

Somatostatin (SRIH) sensitivity in acromegaly was evaluated in vivo by comparing the inhibition of GHRH (1 microgram/kg, iv)-stimulated GH secretion in eight acromegalic and six normal subjects. A SRIH infusion (50 micrograms/h) that inhibited the mean plasma GH response to GHRH by 74 +/- 5% (+/- SE) in normal subjects had no significant effect in the acromegalic patients. However, when two acromegalic patients in whom SRIH had no suppressive effect were excluded from the analysis, the effect of SRIH in the other six (82 +/- 7%) was comparable to that in the normal subjects. Within the acromegalic group, the percent suppression of basal and GHRH-stimulated GH secretion was inversely correlated with both basal plasma GH (r = -0.751; P = 0.03 and r = -0.727; P = 0.04, respectively) and insulin-like growth factor I (r = -0.800; P = 0.02 and r = -0.727; P = 0.04, respectively) concentrations. The in vitro sensitivity to SRIH was studied in pituitary adenomas from five of the acromegalic patients in 3- to 4-day monolayer cultures of dispersed cells. The SRIH IC50 values were lowest in the tumors (8.6-44 pmol/L) from the three patients who had in vivo SRIH sensitivity (suppression of GHRH-stimulated GH secretion) comparable to that in the normal subjects. The IC50 values were higher in the tumors (150 and 21,000 pmol/L) from the two patients that were least responsive to SRIH in vivo. These results indicate that there is considerable variability of SRIH sensitivity in patients with acromegaly. Although the role of this defect in the pathogenesis of acromegaly is uncertain, it may be an important determinant in the degree of elevation of plasma GH levels.

This study evaluated the effects of medroxalol on prolactin secretion. Twelve normal subjects received medroxalol, 1 mg/kg, intravenously and on a separate occasion, 5% dextrose in water. Integrated prolactin secretion during the 3 hours after medroxalol injection was significantly increased as compared with dextrose (P less than 0.001). Intravenous administration of medroxalol, 2 mg/kg, to 10 hypertensive subjects resulted in significant elevation of mean prolactin levels above basal levels at all time intervals measured from 30 to 240 minutes after injection. Oral medroxalol administration to 11 hypertensive subjects for up to 15 months did not alter mean prolactin levels. Medroxalol neither stimulated prolactin release nor decreased dopamine suppression of prolactin release from pituitary cell cultures. In conclusion, intravenous medroxalol stimulates prolactin secretion in both normal and hypertensive subjects. This effect is not likely mediated by a direct action of the drug on the pituitary but rather by an effect either within the central nervous system or of a drug metabolite.

Observations from a network of radars on ships and on islands in the western North Atlantic Ocean and on the eastern coast of North America suggest that successful autumnal migrants moving between North and South America utilize simple compass orientation and do not require bicoordinate navigation. Successful migrants maintained a southeast heading from the North American coast to the Caribbean, Unsuccessful migrants became disoriented over the Atlantic. Visual observations suggest that successful migratory behavior is restricted to certain taxonomic groups of passerines.

Excerpt Hemochromatosis is a disorder characterized by the deposition of iron in various tissues and organs. Studies have shown altered pituitary target organ dysfunction associated with this disea...

Bird migration through an imposed ELF field was studied at the U.S. Navy Wisconsin Test Facility at Clam Lake, Wisconsin. More than 15,000 birds were followed with a small, mobile, short range, high resolution search radar, the ORNITHAR, as they flew over the WTF antenna system which was activated in pre-determined sequences without the knowledge of the observers in the mobile radar. Observations in the vicinity of the transmitter at the WTF revealed a significant association of several migratory behavior variables with antenna state. The most regular of these was a 5 deg. to 20 deg. deviation in the track direction of migrants when the north-south antenna leg was activated. This and other effects did not occur on all nights of observation and neither the occurrence not the magnitude of the effect could be predicted from weather variables or direction or intensity of migration. Subsequent radar observations near the WTF antenna but remote from the transmitter site failed to reveal any effects regularly associated with antenna state such as those noted near the transmitter. The factors responsible for the observed effects near the transmitter site are not known but may still be due to an electromagnetic field.

Neotropical bats, Phyllostomas hastatus, were released 10 kilometers from their home roost, and their homeward flights were tracked by radio. Flights of bats with unimpeded vision were strongly oriented in the homeward direction, while the flights of blindfolded bats did not show this marked orientation.