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Nonpolar resistive switching (RS), a combination of bipolar and unipolar RS, is demonstrated for the first time in a single nanowire (NW) system. Exploiting Ag@TiO2 core–shell (CS) NWs synthesized by postgrowth shell formation, the switching mode is controlled by adjusting the current compliance effectively, tailoring the electrical polarity response. We demonstrate ON/OFF ratios of 105 and 107 for bipolar and unipolar modes, respectively. In the bipolar regime, retention times could be controlled up to 103 s, and in the unipolar mode, >106 s was recorded. We show how the unique dual-mode switching behavior is enabled by the defect-rich polycrystalline material structure of the TiO2 shell and the interaction between the Ag core and the Ag electrodes. These results provide a foundation for engineering nonpolar RS behaviors for memory storage and neuromorphic applications in CSNW structures.

Plant defences may negatively affect the oviposition behaviour of insect herbivores. We exposed adult female mountain pine beetles Dendroctonus ponderosae (Hopkins) to monoterpene vapours and assessed their subsequent oviposition in lodgepole pine Pinus contorta. Exposure to 31.25 and 125 p.p.m. of α-pinene and limonene for 24 h did not affect the survival or establishment of oviposition galleries compared with controls. Females had fewer, smaller eggs and therefore lower cumulative reproduction after exposure to 125 p.p.m. compared with the other treatments. Limonene negatively affected oviposition more than did α-pinene. Female body condition, a measure of energetic state, influenced the responses (i.e. significant interactions between condition and monoterpene concentration). With exposure to 31.25 p.p.m., females in better condition tended to have fewer, larger eggs, whereas females in poorer condition tended to have more, smaller eggs, compared with controls. Overall, reproductive investment declined with body condition when exposed to monoterpenes. Egg size and number increased with female body size. The findings of the present study may indicate the toxic effects of monoterpenes or may be a result of females choosing not to invest in adverse environments depending on body condition. In either case, reduced reproduction when exposed to high plant defences may be increasingly important as climate change affects plant defences.

Radiological imaging remains the cornerstone of follow-up of patients with urolithiasis. Plain abdominal X-ray (XRKUB) of these patients is largely becoming obsolete in favor of noncontrast computed tomography of the abdomen and pelvis (CTKUB), which offers superior sensitivity and specificity. Contentiousness exists, however, related to the radiation doses associated with CT. Calcium oxalate remains the most common stone composition across most populations. These calculi are radiopaque and thus follow-up with XRKUB may be appropriate in some settings, avoiding the higher radiation doses associated with standard protocol CT. With the emergence of low-dose CT, however, and the modest accuracy of XRKUB, the ongoing role for XRKUB in the management of urolithiasis is debatable. In this study, we assessed the proportion of pure calcium urolithiasis visible on XRKUB to assess the utility of XRKUB for follow-up of pure calcium urolithiasis. Hospital laboratory databases were analysed to identify patients who had undergone urological intervention and extraction of urolithiasis composed of pure calcium salts, who had undergone CTKUB and XRKUB during the same episode for diagnosis of the calculus. One hundred five calculi were included and the imaging for each patient analyzed. 79/105 calculi (75%) identified on CT were visible on XRKUB. The median calculus visible on XRKUB was 7.0 mm (interquartile range [IQR] 5.0-10.0 mm), the median calculus not seen was 4.25 mm (IQR 3.5-7.0 mm) as measured on CT (p 0.01). XRKUB accuracy varied according to calculus position within the renal tract. Calculi were most often visible in the renal pelvis and proximal ureter (86%), 50% of mid-ureteral and 72% of distal ureteral calculi were visible (p = 0.01). Until low-dose CT protocols become widely adopted, XRKUB still has a limited role in the management of pure calcium urolithiasis in selected patients. Due to its modest accuracy in many settings, this role is limited mainly to larger proximal urolithiasis.

Dissolution testing of solid oral dosage forms plays a critical role in product development by providing a link (1) between drug release and bioavailability (BA) and bioequivalence (BE) and (2) between drug release and formulation and manufacturing process variables (1–4). The importance of dissolution in quality assurance and regulatory science is well known (5–7). In vivo–in vitro correlations and relationships (IVIVC/R) can be established when in vivo absorption is solubility- or dissolution rate-limited. A correlated dissolution test allows waiver of clinical studies for the documentation of BA, BE, and, scale-up and post-approval changes (SUPAC; 5,7). USP dissolution apparatus 1 and 2 are widely used for testing solid oral dosage forms (8). As with any analytical equipment, and perhaps particularly with dissolution assemblies, installation qualification (IQ), operational qualification (OQ), and performance qualification (PQ) are important. For a dissolution assembly, mechanical calibration provides OQ. For the assembly, analysis, and analytical procedure, the USP dissolution procedure as described in General Chapter Dissolution and other General Chapters, together with USP Prednisone Reference Standard (RS) and other Reference Standard Tablets provides PQ (9). Beyond these cGMP approaches, USP’s physical tablets support proficiency testing, thus leading to USP’s new term Performance Verification Test (PVT) for the term apparatus suitability in (10,11). USP has extensively studied the quality attributes of USP Lot P Prednisone RS Tablets and their sensitivity to selected variables of the dissolution test procedure using apparatus 1 and 2 (12–14). Some have argued that dissolution testing is specific to a particular product and thus have recommended the use of in-house standards for PQ of dissolution equipment (15,16). Some members of the scientific community are also of the opinion that USP RS Tablets contribute much of the variability observed in dissolution testing (17). The purpose of the study reported here was to determine the dissolution variability associated with selected commercial dosage forms in comparison to USP Lot P Prednisone RS Tablets. The secondary purpose was to gain data that would inform the process of choosing an RS for dissolution PQ. A product that displayed low variability (repeatability) and sensitivity to selected variables during dissolution testing would be an ideal dissolution RS. This study did not attempt to evaluate the quality of the commercial medicines for their intended therapeutic use.

Diabetes care has become increasingly complex. We set out to quantify recent trends in the complexity of medication regimens and test ordering for diabetes patients continuously enrolled in health plans affiliated with a large, regional US health maintenance organization, with representation in the South and Midwest.We provide descriptive trends analysis of overall diabetes care complexity (number of components [i.e., glucose, blood pressure, cholesterol control], number of medications/tests) from 1995 to 2003 for adults with diabetes (N = 304,233).The main outcomes were (1) the proportion of patients receiving diabetes-related medications (blood glucose, blood pressure, and cholesterol control agents), (2) the average number of medications, (3) the proportion of patients receiving diabetes-related tests (glycosylated hemoglobin [HbA1c], urine microalbumin, and serum cholesterol), (4) and the average number of tests ordered within the first year that a patient had any indication of diabetes.The proportion of patients on cholesterol lowering drugs (18% --39%, p0.01) and blood pressure lowering drugs (51% --62%, p = 0.04) rose significantly, while the proportion on glucose lowering drugs fell (76% --47%, p0.01). Among patients prescribed medications, the average total number of diabetes-related medications rose from 2.96 to 3.70 medications (p0.01) with smaller increases seen for glucose lowering (1.45 --1.65, p0.01) and blood pressure lowering regimens (2.14 --2.51, p0.01), and no change for cholesterol lowering drugs (1.23 --1.19, p = 0.19). For laboratory tests, the proportion receiving cholesterol (40% --58%), and urine microalbumin (4% --18%) (all p's0.01) rose significantly, while the testing rates for HbA(1c) remained unchanged. The average total number of tests ordered per year increased significantly from 3.34 to 4.10 (p0.01) with more modest increases observed for individual tests.Trends analyses are unadjusted for many clinical characteristics that might influence the complexity of diabetes care.Diabetes care grew more complex with the largest change in the number of patients receiving multi-component diabetes care. While the use of blood pressure and cholesterol lowering drugs rose overall, the proportion of patients using glucose lowering drugs declined and the average number of prescribed glucose lowering drugs did not increase in a clinically significant manner.

This study evaluated the sensitivity of USP Prednisone tablets (Reference Standard Lot P0E203) to dissolved gas in the medium in USP Apparatus 2. This lot will be introduced into commerce over the summer of 2006 as a replacement for current Lot O0C056. The effect of deaeration techniques and water purification methods on dissolution was also studied. Dissolution tests were performed in water containing nine different concentrations of dissolved gas. The oxygen and total dissolved gas pressure was monitored using a dissolved gas and oxygen meter. Other experimental variables such as the equipment,shaft position,and vessel position were kept constant throughout the study. The same analyst performed all studies. The study tablets were highly sensitive to dissolved gas in USP Apparatus 2. An increase in both the amount of prednisone dissolved and the variability of results was observed when the dissolved oxygen concentration exceeded 6 mg/L. The corresponding sum of the partial pressure of gases other than oxygen and the percent saturation were 510 mm Hg and 68%,respectively.

This study estimates the impact of the price of alcoholic beverages on latent dimensions of current alcohol dependence and abuse. A three-part econometric model is used to estimate the impact of price on three latent dimensions (factors). For heavier drinking, the estimated price elasticity is -1.325 (P = 0.027); for physical and other consequences of drinking, -1.895 (P = 0.003); for increased salience of drinking, -0.411 (P = 0.339). For a single latent factor characterized simply as dependence/abuse, estimated price elasticity is -1.487 (P = 0.012). These results suggest that higher prices for alcohol reduce important dimensions of current alcohol dependence and abuse.

This study explored the use of near-infrared spectroscopy (NIRS) for the rapid analysis of organic C (Corg) and organic N (Norg) in the A horizon of soil within a single field. Soil was sampled throughout a field in Manitoba, Canada to capture soil variability associated with topography. The soil samples were oven-dried and treated with acid to remove carbonates, after which C and N were determined by dry combustion. In this study, portions of the dried soil samples not treated with acid were scanned with a near-infrared scanning spectrophotometer between 1100 and 2500 nm. Correlating the spectral and the chemical analytical data using multiple linear regression or principal component analysis/partial least squares regression gave useful correlations for Corg. Over the range of 0–40 mg g-1 Corg, NIR-predicted values explained 75–78% of the variance in the chemical results. Results were improved to 80% for calibrations developed for the 0–20 mg g-1 organic C range. Useful results were not obtained for Norg although the literature shows that total N in soil is predictable using NIRS. It is likely that the acid treatment altered the composition of the samples in an inconsistent manner such that the chemically analyzed samples and those scanned by NIRS were different from each other in Norg concentration or composition. Extrapolation of these Corg results to the landscape scale implies that NIRS has potential to be a suitable method for mapping C for the purposes of monitoring C sequestration. Key words: Near-infrared spectroscopy, soil, carbon, nitrogen, topography, soil monitoring

The development of a thin-layer chromatography method for the separation and identification of polymyxin B sulfate, neomycin sulfate, and bacitracin zinc in ointments, either alone or in combinations, is described. The ointments were dispersed in chloroform and the components of interest were extracted into an aqueous 0.1 N hydrochloric acid layer. The stationary phase was silica gel G and the mobile phase consisted of a mixture of methanol, ethanol, methylene chloride, ammonium hydroxide, and water (3 : 3 : 2 : 2 : 1.5, v/v) or methanol, isopropanol, methylene chloride, ammonium hydroxide, and water (4 : 2 : 2 : 2 : 1.5, v/v). Detection was performed by spraying with a 0.2% solution of ninhydrin in 1-butanol. A number of commercial samples were analyzed using the described method. Our method worked on all brands tested, except one brand of the three-component ointment (Brand A), which contained interfering excipients. A sample clean-up step was developed to remove the interferences. The method described ...

The use of discrete management units for variable-rate N fertilization requires that factors influencing grain yield response to N fertilizer are adequately characterized by delineating landscapes into such management units. The objective of this study was to compare the use of topographically derived landform element complexes (LEC) and the use of individual soil series as management units. Soil volumetric moisture content, nitrate-N, exchangeable ammonium-N, extractable phosphorus, exchangeable potassium, and sulphate-sulphur were studied in 10 intensively sampled transects in an undulating glacial till landscape near Miniota, Manitoba. The study site was delineated into upper, mid and lower LEC using a digital elevation model derived from relative elevation data. The LEC were useful in capturing gross variability at a manageable landscape scale. Among LEC there was a general trend of lower > mid > upper for median values of soil moisture, nitrate, phosphate, potassium and sulphate, as these attributes generally increased with convergent landscape character. Differences among LEC were often statistically significant, and relative distributions exhibited temporal persistence. The site was also stratified by soil series, including Newdale, Varcoe and Angusville soils (Black Chernozems), which were identified by examination of individual soil cores at each sample point. Stratifying the site into management units using soil genetic information, which is reflective of historical moisture conditions and biomass production, was expected to be superior. There was little advantage, however, in using soil series rather than LEC. Spatial distributions of the most agronomically relevant attributes (soil moisture and nitrate) were expressed at a landscape scale broader than that at which soil series occurred within the site. While there were important differences among soil series with respect to nutrients such as phosphate and sulphate, the site was better stratified by LEC with respect to soil moisture and nitrate. Key words: Soil-landscape, soil series, soil moisture, soil residual nitrate, extractable phosphorus

Methyl bromide has been the foundation of chemical weed control in strawberry (Fragaria ×ananassa) in California for over 40 years. The impending phaseout of methyl bromide may leave strawberry producers dependent on less efficacious alternative fumigants for weed control. The use of herbicides to supplement fumigants is a potential weed control strategy for strawberry. A 2-year field study was conducted in California to evaluate 10 herbicides as possible supplements for methyl bromide alternative fumigants. Herbicides were applied immediately after transplanting (immediate posttransplant), and 3 weeks after transplanting (delayed posttransplant). Napropamide applied immediate posttransplant was included as a commercial standard. Immediate posttransplant treatments that were safe in strawberry include carfentrazone at 0.075 and 0.15 lb/acre (0.084 and 0.168 kg·ha-1), flumioxazin at 0.063 lb/acre (0.071 kg·ha-1) and sulfentrazone at 0.175 and 0.25 lb/acre (0.196 and 0.28 kg·ha-1). Triflusulfuron at 0.016 lb/acre (0.017 kg·ha-1) was the only delayed posttransplant treatment with acceptable selectivity. Among the selective herbicides applied immediate posttransplant, flumioxazin and napropamide provided the most consistent control of bur clover (Medicago polymorpha) and shepherd's purse (Capsella bursa-pastoris). Triflusulfuron applied delayed posttransplant did not significantly reduce bur clover densities, but did reduce shepherd's purse densities.

This study evaluated the utility of (S)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-(3-[18F]fluoropropyl)-2,3-dimethoxybenzamide ([18F]fluoropropylepidepride), [18F]5-FPrEpid, as a ligar d for PET studies of cerebral dopamine D2 receptors. The in vitro affinity for the rat striatal dopamine D2 receptor, KD 138 pM, was determined by Scatchard analysis of in vitro binding to rat striatal homogenate. The apparent lipophilicity, log kw 1.6, was measured with reverse phase HPLC at pH 7.5. The receptor specificity was determined by competitive displacement of [18F]5-FPrEpid by a variety of neurotransmitter ligands. Only dopamine D2 ligands displaced [18F]5-FPrEpid with high affinity. Positron tomographic imaging studies in primates of [18F]5-FPrEpid demonstrated a stable striatal uptake. of 0.02% injected dose/ml for up to 5 h after injection. The striatal: cerebellar ratio increased from 2 at 15 min, to 7 at 200 min, and to 10 at 300 min. Striatal uptake was displaceable by haloperidol (1 mg/kg) or raclopride (2.5 mg/kg) to cerebellar levels with a t1/2 of washout of 9 or 15 min. Striatal uptake was mildly susceptible to displacement by d-amphetamine (1–2 mg/kg) released endogenous dopamine; d-amphetamine administration produced a 10%/h increase in the rate of striatal washout. Although uptake in the striatum is reversible, an equilibrium between receptor bound [18F]5-FPrEpid in striatum and [18F]5-FPrEpid in plasma is not reached within 5 h postinjection. © 1993 Wiley-Liss. Inc.

Tetrafluoroethylene (TFE) is commonly used as a slide surface mating with polished stainless steel in bridge bearings that accommodate translation and rotation of the superstructure relative to the substructure. The primary requirement of the slide surface is a low coefficient of friction that is maintained throughout the service life of the bearing. The paper reports on a laboratory investigation comprising 14 tests undertaken at room temperature under simulated field conditions that was performed to determine the effect of contamination on the coefficient of friction in a lubricated TFE/stainless steel interface. It is shown that the friction of a lubricated surface increases significantly with a relatively low amount of contamination in the form of unhydrated portland cement in the interface, emphasizing the need for assembling bearings in a dust-free environment and avoiding disassembling of bearings on site. The influences of the degree of contamination on the coefficient of friction at initial movement and after 200 cycles of movement, as well as on the peak value of the coefficient of friction recorded during a test, are discussed.

A prospective observational study was conducted to investigate the effects of nutrition and related factors on the outcome of pregnancy in nulliparous African American women 16–35 years of age. Blood samples from a subset of these subjects were taken during the first (1st), second (2nd) and third (3rd) trimesters of pregnancy and at delivery. Cord blood samples were also collected at delivery. Levels of selected biochemical variables including serum ferritin, vitamin B 12 and folate as well as whole blood folate, and selected hematologic indices were determined and correlated with pregnancy outcome variables. During the second trimester of pregnancy, values for hematocrit and hemoglobin were less than 30% and 11 g/dL, respectively, in 16% and 30% of the participants, respectively. Serum and whole blood (WB) folate increased sequentially during pregnancy. Cord concentrations of serum folate were significantly higher than maternal concentrations at delivery (P 2 =0.21), while gestational age was inversely correlated with 3rd trimester vitamin B 12 (R 2 =0.34). These data suggest that vitamin B 12 and folate play an important role in the outcome of pregnancy in this population.

The presence and the extent of the plume of Hamilton Harbour water extending into Lake Ontario was determined in order to assess the importance of metal contaminant transport from Hamilton Harbour into Lake Ontario. Industrially derived Fe compounds, wustite and hematite, were used as plume tracking parameters. Wustite, particularly, proved to be a good tracer of the plume. Annual loadings of particulate heavy metals to Lake Ontario were calculated using the concentrations of heavy metals in suspended solids from the connecting Burlington Canal, Hamilton Harbour and western Lake Ontario. Annual loadings of heavy metals to lake Ontario are ∼266 × 103 kg Fe, 9.33 × 103 kg Zn, 1356 kg Pb, 273 kg Cu, 8.7 kg Cd. The relative contribution of the total metal load from Hamilton Harbour to Lake Ontario is negligible when compared to the load from the Niagara River. Lake-harbour water exchange and the high Fe concentrations in benthic sediments of Hamilton Harbour increase P retention in the harbour sediments, thus are beneficial to water quality in Hamilton Harbour.

(S)-(−)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-[123I]iodo-2,3-dimethoxybenzamide (TDP 517) (proposed generic name, [123I]epidepride) is the iodine-123 substituted analogue of isoremoxipride (FLB 457), both of which are very potent dopamine D-2 antagonists (epidepride KD 0.024 nM). [123I]Epidepride was radioiodinated in 60–70% radiochemical yields in 35 min from the corresponding 5-(tributyltin) derivative using Na123I with a specific radioactivity of 3000 Ci/mmol, and oxidized in situ with chloramine-T. The aryltin precursor was prepared from non-labelled epidepride by palladium-catalyzed stannylation using bis(tri-n-butyltin) in triethylamine. Alternatively, using no carrier-added Na125I as the radioisotope, [125I]epidepride at 2000 Ci/mmol specific radioactivity was prepared in 86% radiochemical yield and 99% radiochemical purity after purification by reverse phase HPLC in ethanolic phosphate buffer.

Epidepride, (S)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-iodo-2,3-dimethoxybenzamide+ ++, the iodine analogue of isoremoxipride (FLB 457), was found to be a very potent dopamine D2 receptor antagonist. Optimal in vitro binding required incubation at 25 degrees C for 4 h at pH 7.4 in a buffer containing 120 mM NaCl, 5 mM KCl, 2 mM CaCl2 and 1 mM MgCl2. Scatchard analysis of in vitro binding to striatal, medial frontal cortical, hippocampal and cerebellar membranes revealed a KD of 24 pM in all regions, with Bmax's of 36.7, 1.04, 0.85, and 0.37 pmol/g tissue, respectively. The Hill coefficients ranged from 0.91-1.00 in all four regions. The IC50's for inhibition of [125I]epidepride binding to striatal, medial frontal cortical, and hippocampal membranes for SCH 23390, SKF 83566, serotonin, ketanserin, mianserin, naloxone, QNB, prasozin, clonidine, alprenolol, and norepinephrine ranged from 1 microM to greater than 10 microM. Partial displacement of [125I]epidepride by nanomolar concentrations of clonidine was noted in the frontal cortex and hippocampus, but not in the striatum. Scatchard analysis of epidepride binding to alpha 2 noradrenergic receptors in the frontal cortex and hippocampus revealed an apparent KD of 9 nM. At an epidepride concentration equal to the KD for the D2 receptor, i.e. 25 pM, no striatal alpha 2 binding was seen and only 7% of the specific epidepride binding in the cortex or hippocampus was due to binding at the alpha 2 site. Correlation of inhibition of [3H]spiperone and [125I]epidepride binding to striatal membranes by a variety of D2 ligands revealed a correlation coefficient of 0.99, indicating that epidepride labels a D2 site. In vitro autoradiography revealed high densities of receptor binding in layers V and VI of prefrontal and cingulate cortices as well as in striatum. In vivo rat brain uptake revealed a hippocampal:cerebellar and frontal cortical:cerebellar ratio of 2.2:1 which fell to 1.1:1 following haloperidol pretreatment. These properties suggest that [125I]epidepride is a superior radioligand for the in vitro and in vivo study of striatal and extrastriatal dopamine D2 receptors.

Concentrations of heavy metals and phosphorus were measured in suspended solids collected from Hamilton Harbour in the spring and late summer of 1986. Forms of iron were determined using Mossbauer spectroscopy and related to the concentrations of heavy metals and phosphorus. Two iron forms, wustite and hematite, originating from anthropogenic activities were identified in addition to naturally occurring Fe2+ from chlorite and clays and Fe3+ from amorphous iron oxides. The highest metal concentrations are found in deep water and in areas adjacent to outfalls. The concentrations of wustite and hematite are correlated with the concentrations of heavy metals, particularly Zn and Pb. Heavy metals in suspended solids exceed guidelines for open water disposal of dredged sediments. Annual loadings of heavy metals to the sediments, calculated from the heavy metal concentrations in suspended solids, are ∼477 × 103 kg Fe, 16 × 103 kg Zn, 3 × 103 kg Pb, 958 kg Cu, 469 kg Ni, and 56 kg Cd. Phosphorus concentrations in suspended solids are high and range between 3,100 mg kg−1 and 7,300 mg kg−1. Higher than average non-apatite inorganic P (NAI-P) concentrations in solids are observed in samples taken from the vicinity of municipal discharges. Manganese and iron were released from bottom sediments during summer anoxia in the hypolimnion of the deep water; however, no phosphorus release was observed. The results indicate that wustite and hematite are good tracers of industrial pollution and their distribution is of importance in determining the particle dynamics in Hamilton Harbour.

A simple and rapid stability-indicating HPLC assay procedure has been developed and validated for metronidazole benzoate. The HPLC conditions were as follows, column: Waters Symmetry C8, 5 microm packing, 4.6 mm x 250 mm; detection: UV at 271 nm; injection volume: 20 microl; mobile phase: acetonitrile-0.1% glacial acetic acid in monobasic potassium phosphate (0.01 M) (40:60, v/v); isocratic elution under ambient temperature at 2.0 ml min(-1). The procedure separated metronidazole benzoate and its potential degradation products, metronidazole and benzoic acid, in an overall analysis time of about 6 min with metronidazole benzoate eluting at about 5 min. The injection repeatability was 0.03%, and the intraday and interday repeatability were 0.4 and 0.7%, respectively. The procedure provided a linear response over the concentration range 0.2-800 microg ml(-1) (r=1.0000) with the limits of detection and quantitation 0.03 and 0.2 microg ml(-1), respectively. The solubilities of metronidazole benzoate in water, 0.01 M hydrochloric acid and 0.05 M phosphate buffer, pH 6.8, determined each in triplicate using the procedure, were 0.2 mg ml(-1) (R.S.D. 7%), 0.4 mg ml(-1) (R.S.D. 2%) and 0.2 mg ml(-1) (R.S.D. 8%), respectively. The results show no detectable hydrolysis of metronidazole benzoate in 0.01 M hydrochloric acid at 37 degrees C or in the mobile phase at ambient temperature in 10 h.

Thirty-two broilers were reared from 1 to 42 d of age on a diet containing 0 or 20 ppm of capsaicin and then conventionally processed. When the cooked meat was served to untrained consumer panelists in a triangle difference test, there was no difference in flavor between control and capsaicin-fed birds for either the Pectoralis muscle (light meat) or the Biceps femoris muscle (dark meat). These data suggest that incorporation of capsaicin into the diets of broilers at 20 ppm does not result in a change in the flavor of the meat.

Epidermal growth factor (EGF) and TRH both produce enhanced prolactin (PRL) gene transcription and PRL secretion in GH4 rat pituitary tumor cell lines. These agents also activate protein kinase C (PKC) in these cells. Previous studies have implicated the PKCepsilon isozyme in mediating TRH-induced PRL secretion. However, indirect studies using phorbol ester down-regulation to investigate the role of PKC in EGF- and TRH-induced PRL gene transcription have been inconclusive. In the present study, we examined the role of multiple PKC isozymes on EGF- and TRH-induced activation of the PRL promoter by utilizing general and selective PKC inhibitors and by expression of genes for wild-type and kinase-negative forms of the PKC isozymes. Multiple nonselective PKC inhibitors, including staurosporine, bisindolylmaleimide I, and Calphostin C, inhibited both EGF and TRH induced rat PRL promoter activity. TRH effects were more sensitive to Calphostin C, a competitive inhibitor of diacylglycerol, whereas Go 6976, a selective inhibitor of Ca(2+)-dependent PKCs, produced a modest inhibition of EGF but no inhibition of TRH effects. Rottlerin, a specific inhibitor of the novel nPKCdelta isozyme, significantly blocked both EGF and TRH effects. Overexpression of genes encoding PKCs alpha, betaI, betaII, delta, gamma, and lambda failed to enhance either EGF or TRH responses, whereas overexpression of nPKCeta enhanced the EGF response. Neither stable nor transient overexpression of nPKCepsilon produced enhancement of EGF- or TRH-induced PRL promoter activity, suggesting that different processes regulate PRL transcription and hormone secretion. Expression of a kinase inactive nPKCdelta construct produced modest inhibition of EGF-mediated rPRL promoter activity. Taken together, these data provide evidence for a role of multiple PKC isozymes in mediating both EGF and TRH stimulated PRL gene transcription. Both EGF and TRH responses appear to require the novel isozyme, nPKCdelta, whereas nPKCeta may also be able to transmit the EGF response. Inhibitor data suggest that the EGF response may also involve Ca(2+)-dependent isozymes, whereas the TRH response appears to be more dependent on diacylglycerol.

[123I]Epidepride, a potent and selective dopamine D2 radioligand, was administered to a 27 year old normal male volunteer. Single photon tomography revealed that peak striatal uptake occurred at 4 h after injection with a striatal:cerebellar ratio of 7.8 rising to over 100 at 18 h post injection. Uptake above the levels seen in cerebellum was also noted in the thalamus, pituitary, hypothalamus and temporal lobe, particularly medially. Single photon tomography with [123I]epidepride allows visualization of extrastriatal dopamine D2 receptors in man.

Although several studies indicate that drinking is responsive to price, little work has focused on whether prices have a differential effect on light, moderate, or heavy drinking. This study examines the price responsiveness of the demand for alcohol: whether heavy drinkers are less sensitive to price than light or moderate drinkers. The study uses data on alcohol consumption on the 1983 National Health Interview Survey. The results indicate that both light and heavy drinkers are much less price elastic than moderate drinkers. Further, we cannot reject the hypothesis that the very heaviest drinkers have perfectly price inelastic demands.

In the past several years our group has synthesized a series of high affinity iodine-123 and fluorine-18 labeled substituted benzamide ligands for SPECT and PET visualization of the dopamine D-2 receptors in brain regions with low receptor density outside the striatum. Radioiodination and radiofluorination in high yield and high specific activity was achieved by using the tributyltin precursor and nucleophilic displacement of the toluensulfonyl ester precursor, respectively.

The hydrogen content of free-standing polycrystalline CVD diamond samples was determined by Fourier Transform Infrared (FTIR) measurements and was quantified by a notched neutron spectrum technique. The latter measures the total bonded and unbonded hydrogen. The concentration of total hydrogen in these samples was of the same order of magnitude. The FTIR measurements, which are sensitive to the bonded hydrogen, indicated different hydrogen to diamond peak ratios.

The regional distribution of striatal and extrastriatal dopamine D2 receptors in human brain was studied in vitro with (S)-N-[(1-ethyl-2- pyrrolidinyl)methyl]-5-[125I]iodo-2,3-dimethoxybenzamide, [125I]epidepride, using post mortem brain specimens from six subjects. Scatchard analysis of the saturation equilibrium binding in twenty-three regions of post mortem brain revealed highest levels of binding in the caudate (16.5 pmol/g tissue) and putamen (16.6 pmol/g tissue) with lower levels seen in the globus pallidus (7.0 pmol/g tissue), nucleus accumbens (7.2 pmol/g tissue), hypothalamus (1.8 pmol/g tissue), pituitary (1.3 pmol/g tissue), substantia innominata (1.0 pmol/g tissue), and amygdala (0.87 pmol/g tissue). Of note was the presence of dopamine D2 receptors in the four thalamic nuclei studied, i.e. anterior nucleus (1.0 pmol/g tissue), dorsomedial nucleus (0.96 pmol/g tissue), ventral nuclei (0.72 pmol/g tissue), and pulvinar (0.86 pmol/g tissue), at levels comparable to the amygdala (0.87 pmol/g tissue) and considerably higher than levels seen in anterior cingulate (0.26 pmol/g tissue) or anterior hippocampus (0.36 pmol/g tissue). The frontal cortex had very low levels of dopamine D2 receptors (0.17-0.20 pmol/g tissue) while the inferior and medial temporal cortex had relatively higher levels (0.31-0.46 pmol/g tissue). Inhibition of [125I]epidepride binding by a variety of neurotransmitter ligands to striatal, ventral thalamic and inferior temporal cortical homogenates demonstrated that [125I]epidepride binding was potently inhibited only by dopamine D2 ligands. The present study demonstrates that dopamine D2 receptors are present in basal ganglia, many limbic regions, cortex and in the thalamus. The density of thalamic D2 receptors is comparable to many limbic regions and is considerably higher than in cortex.(ABSTRACT TRUNCATED AT 250 WORDS)

Studies of [123I]epidepride uptake in rhesus monkey brain were performed using single photon tomography. Striatal uptake peaked at 0.85% of administered dose/g at 107 min post-injection, then declined slowly to 0.70% of administered dose/g at 6 h. Striatal:posterior brain ratios rose from 2 at 25 min to 6.8 at 105 min, to 15 at 4 h and to 58 at 6.4 h. [123I]Epidepride was displaced by haloperidol (0.1 and 1 mg/kg) with a half-life of washout of 55 min. Little displacement of [123I]epidepride was observed following administration of 1 or 2 mg/kg d-amphetamine, respectively, indicating [123I]epidepride is not easily displaced by endogenous dopamine. In vitro equilibrium binding studies using rat striatum revealed a KD of 46 pM and Bmax of 33 pmol/g tissue at 37 degrees C, while at 25 degrees C the KD was 25 pM and the Bmax 32 pmol/g tissue. In vitro kinetic analysis of association and dissociation curves revealed a half-life for receptor dissociation at 37 degrees C of 15 min and 79-90 min at 25 degrees C. Allowing for the temperature difference, there is good correspondence between in vivo and in vitro dissociation kinetics at 25 degrees C. Increasing in vitro incubation temperature from 25 to 37 degrees C caused a 6-fold increase in the dissociation rate, suggesting that there is a change in binding kinetics at the dopamine D2 receptor at 37 degrees C compared to in vivo binding. The results of this study indicate that [123I]epidepride is an excellent radioligand for SPECT studies of the dopamine D2 receptor in man.

Remoxipride (Figure 1), a substituted benzamide analog of sulpiride, was developed as a potential antipsychotic agent on the assumption that the poor bioavailability of sulpiride was due to hydrolysis of the amide bond.1 In the rat, remoxipride was shown to be 10 times weaker than sulpiride in blocking dopamine D2 receptors in vitro, but in vivo was 50 times more potent.2 This observation led to the development of the 6-methoxysalicylamide series, of which raclopride is the best known member and eticlopride is the most potent.3

SUMMARY. One-day-old leghorn chicks were placed in floor pens on previously used poultry litter (potentially providing exposure to normal chicken enteric flora) for 7 days and provided feed containing one of several antibiotics or anticoccidials. On day 7, all groups were challenged orally with an isolate of Salmonella enteritidis (106 colony-forming units) that was resistant to bacitracin, novobiocin, nalidixic acid, and nitrofurazone. All chicks were killed on day 13, and liver, spleen, and cecal tonsils were cultured. Dietary administration of novobiocin (0.385 g/kg) caused a significant increase (P < 0.05) in positive chick colonization rate (either liver and spleen or cecal tonsils) compared with the unmedicated controls. Similarly, chicks administered dietary nitrofurazone (0.3 g/kg) were infected with S. enteritidis at a significantly greater frequency than the unmedicated controls. A significant decrease in cecal volatile fatty acid concentration, previously shown to influence susceptibility to selected enteric pathogens, was observed in the novobiocin- and nitrofurazone-treated groups. Treatment with chlortetracycline (11.4 g/kg), monensin (0.91 g/kg), or nicarbazin (0.49 g/kg) had no effect on S. enteritidis invasion or colonization. Bacitracin (0.49 g/kg) significantly increased S. enteritidis cecal colonization rate when administered continuously throughout the study. These data support and extend previous investigations involving other salmonellae and indicate that selected antibiotics may increase the severity and frequency of S. enteritidis colonization and invasion rate in leghorn chicks. RESUMEN. Efecto de algunos antibi6ticos y anticoccidianos sobre la colonizaci6n cecal por Salmonella enteritidis y la invasi6n de los organos en aves tipo leghorn. Pollitos tipo leghorn de un dia de edad fueron colocados durante siete dias en corrales en piso sobre cama previamente utilizada para asi suministrar una exposici6n a flora enterica de pollos normales. Las aves fueron alimentadas con alimento que contenia uno de varios antibioticos o anticoccidianos. A los siete dias de edad todos los grupos fueron desafiados oralmente con 106 unidades formadoras de colonia de Salmonella enteritidis resistentes a la bacitracina, novobiocina, acido nalidixico y nitrofurazona. Todos los pollos se sacrificaron al dia 13 y se cultivaron el higado, bazo y tonsilas cecales. La administraci6n de novobiocina en el alimento a dosis de 0.385 g/kg caus6 un aumento significante (P < 0.05) en al procentaje de colonizaci6n en los pollos en el higado, bazo o tonsilas cecales, comparados con los controles no medicados. Asi mismo, los pollos que recibieron nitrofurazona en el alimento a dosis de 0.3 g/kg fueron infectados con S. enteritidis a una frecuencia significantemente mayor que los controles no medicados. En los grupos tratados con novobiocina y nitrofurazona se observ6 una disminuci6n significante en la concentraci6n de acidos grasos volatiles en el ciego, que influencian la susceptibilidad frente a algunos pat6genos ent&ricos. El tratamiento con clortetraciclina (11.4 g/kg), monensina (0.91 g/kg), o nicarbacina (0.49 g/kg) no tuvo efecto sobre la invasi6n o colonizaci6n de S. enteritidis. La bacitracina (0.49 g/kg) significantemente aument6 la colonizaci6n cecal de S. enteritidis cuando fue administrada continuamente durante el estudio. Estos datos respaldan los resultados obtenidos en investiga

SUMMARY. The effect of continuous (42 days) dietary administration of 5 or 20 ppm capsaicin to broiler chickens on Salmonella enteritidis susceptibility, body weight, and feed efficiency was investigated. Chickens were weighed at 1, 21, and 42 days of age. No significant differences in body weight or feed efficiency were observed. Chickens were challenged with 1 x 108 colony-forming units of S. enteritidis at 21, 28, or 42 days of age. The S. enteritidispositive culture rate for cecal tonsils was significantly lower (P < 0.05) in the treatment groups receiving 5 ppm or 20 ppm dietary capsaicin than in the untreated control group at all challenge times. Dietary capsaicin (5 and 20 ppm) resulted in protection against S. enteritidis organ invasion at 28 days in one experiment and at both 21 and 42 days in the other. These results indicate that continual dietary capsaicin administration increases resistance to S. enteritidis colonization and organ invasion throughout the normal growth period without detrimental effects on growth in broiler chickens.

The effect of oral inoculation with anaerobic cultures of cecal microflora and providing lactose in the feed on colonization resistance to invasive Salmonella enteritidis was evaluated in newly hatched leghorn chicks. Salmonella colonization of the ceca, tissue invasion and organ colonization, horizontal transmission, and seroconversion were significantly decreased (P less than 0.01) in chicks inoculated with cecal flora. The addition of lactose to the feed, in the absence of cecal microflora, failed to provide protection. Dietary lactose enhanced colonization resistance in chicks that were inoculated with anaerobic cultures of cecal flora. The results indicated that establishment of normal cecal flora in layer chicks together with the addition of lactose to the diet markedly increases resistance to cecal colonization and organ invasion, and decreases horizontal transmission of S. enteritidis.

New procedures are reported for the specification of caging yields in nuclear recoil chemistry experiments. All five hot 18F substitution channels in CH3CF3 and CH3CHF2 exhibit caging at large density. The respective total caged yields at 195 °K are 4.0%±0.6% and 5.6%±0.6%, and the total yields of stabilized substitution products are 8.9%±0.4% and 8.6%±0.6%. The simplest plausible caging mechanism involves primary Franck–Rabinowitsch radical recombination of 18F atoms with aliphatic radicals. Density‐variation results cannot be used for the qualitative detection of caging reactions unless excitation‐stabilization complications have been shown to be unimportant.

Nuclear recoil 18F reactions in CH3CHF2 have been investigated throughout the effective pressure range 0.3–190 atm. The principal reaction channel is F‐to‐HF abstraction for which the combined yield from quasithermal and energetic processes in the presence of 5 mole% H2S additive is 83.4%±0.2%. A reaction mechanism is proposed that involves the organic product forming channels F‐for‐F, F‐for‐αH, F‐for‐βH, F‐for‐ĊH3 and F‐for‐ĊHF2. The results are compared with those reported for the 18F+CH3CF3 system.

The forms of phosphorus and iron have been determined in suspended solids collected from within and off the Grand River estuary, Lake Erie, in August and October of 1985. Concentrations of organic and inorganic carbon, aluminum, and manganese were also measured. These chemical parameters were then used to assess the importance of processes such as input of stream solids, biological productivity, shoreline erosion, and lake sediment resuspension in regulating suspended solids composition in the studied area. Considerable spatial and temporal variation was found in the distribution of the measured parameters. Both total and bioavailable P (BAP) in suspended solids were higher in the summer than in the fall, BAP accounting for about 34.5% of total P in August and about 17.5% in October. The BAP distribution is consistent with the distribution of ferric ion, whereas apatite-P follows the distribution of aluminum and ferrous ion in chlorite and other clay minerals. The concentration of BAP is generally higher in the near-surface solids and increases with increasing distance from the river mouth. The seasonal and spatial trend in total P, BAP, organic carbon, and Fe3+ concentrations reveal that a large proportion of particulate P is associated with particles of biogenic origin, rather than inorganically bound to Fe oxides. The apatite-P, Al, and Fe2+ concentrations reveal the importance of sediment resuspension processes, within the distance of ∼4 km, particularly in the fall. The same parameters point to loss of terrigennous material of riverine origin and from the shoreline erosion within the short distance from the river mouth.

The limiting low pressure yield behavior has been characterized for gas phase substitution reactions of energetic 3H and 18F atoms with aliphatic and alicyclic substances. The limiting yields correlate well with the respective critical energies for secondary unimolecular decomposition. The interpretation of this behavior leads to quantitative descriptions for the hydrogen-for-hydrogen and F-for-F primary product internal excitation energy distributions together with approximate descriptions of total energy disposal for the threshold hydrogen-for-hydrogen processes.

Nuclear recoil 18F reactions in CH3CF3 have been investigated throughout the effective pressure range 0.3–170 atm. The principal reaction channel is F‐to‐HF abstraction for which the combined yield from thermal and energetic processes in the presence of 5 mol% H2S additive is 84.4%±0.1%. Organic‐product‐forming channels include F‐for‐F, F‐for‐2F and F‐for‐H atomic substitution and F‐for‐CH3 and F‐for‐CF3 alkyl replacement with respective primary absolute yields of 4.21%±0.10%, 0.26%±0.03%, 5.75%±0.14%, 1.04%±0.03%, and 1.33%±0.04%. With the exception of the F‐for‐2F channel substantial portions of the organic primary products contain sufficient internal excitation to induce secondary decomposition. At low pressures the average fractional decompositions following single substitution (F‐for‐X) and alkyl replacement (F‐for‐R) reactions are 0.80±0.03 and 0.27±0.04. Alkyl replacement products are fully stabilized through collisional deactivation at pressures below ∼13 atm. At 170 atm only 0.60±0.05 of the single‐substitution products have undergone collisional stabilization, representing 0.50±0.04 of the species capable of decomposition. Experiments with CH3CF3/C3F6 mixtures demonstrated average reaction energy differences for F‐to‐HF and organic‐product‐forming processes in CH3CF3 vs olefinic addition in C3F6.

The rate constant for the reaction of O (P-3) atoms with ClONO2 at 10 torr total pressure is assessed over the temperature range 225-273 K by the flash photolysis resonance fluorescence technique. The data, taken together with results given by Molina et al. (1977), have been used to formulate an Arrhenius expression suitable for stratospheric modeling applications. Comparison of the rate of ClONO2 destruction via the oxygen atom reaction with the solar photolysis rate shows that chemical reaction accounts for less than 15% of the CLONO2 removal at altitudes between 20 and 30 km.

Fluorine-18 has been standardized using three counting systems: (i) the NBS pressurized “4π”γ ionization chamber, (ii) a 4πβ liquid-scintillation counter, and (iii) a Ge(Li) gamma-ray spectrometer previously calibrated with sodium-22. The results of the three measurements agreed to within 1 percent. Solution standards of fluorin-18 were used at the NIH to calibrate counting systems used in positron-emission tomography (PET) for nuclear medicine.

A technique involving flash photolytic production and resonance fluorescence detection of O atoms coupled with cw production of vibrationally excited reactant molecules using a CO2 laser is described. The method relies on the high sensitivity and precision of the flash photolysis resonance fluorescence technique to compare reaction rates measured with the laser off with those measured with the laser on, thereby assessing any effect of reactant vibrational energy on the dynamics of the chemical reaction. The limiting value of the laser enhancement that can be discerned depends ultimately on two factors: (1) the equilibrium concentration of vibrationally excited reactant that can be experimentally realized (i.e., absorption of laser flux vs deactivation losses), and (2) the magnitude of the activation energy for the thermal reaction. This determines the extent of a purely thermal (heating) effect. We observed little or no effect of vibrational energy in C2H4 on the rate of reaction with O atoms. Because of ...

1. The effect of reducing food intake to 75% of the ad libitum intake was determined from hatching to 8 weeks in young Light Sussex chickens. 2. Restricted birds were lighter throughout the experiment. 3. Relative adrenal weight tended to be greater in restricted birds but the difference decreased with time. 4. There was no depletion of adrenal cholesterol: from week 5 there was a significantly greater amount in the adrenals of restricted birds. 5. After 1 week of restriction plasma corticosterone concentration was 73% greater than in controls. It decreased progressively, falling within the normal range at 5 weeks. 6. Restricted birds were hypoglycaemic from weeks 2 to 7 and hyper‐lipacidaemic throughout. A negative correlation between plasma glucose and free fatty acids was found.

Samples of chloritoid (a “layered” orthosilicate) from three distinct geological sources have been examined, both in the naturally occuring and heat-treated forms, by Mossbauer spectroscopy. This technique is shown to elucidate the environment of the iron present constitutionally: there is, for example, only one type of site (with octahedral symmetry in the so-called L1 layer) occupied by Fe2+. The Fe3+ ions are present to such a small extent that it did not prove feasible to evaluate their preferred siting. One of the samples (that coming from Rhode Island) displayed an anomalous Fe2+ doublet which, by a combination of energy dispersive analysis and electron diffraction (i.e., analytical electron microscopy) and spectrochemical analysis, was shown to arise from minute intergrowths of ilmenite (FeTiO3).

The partitioning of radiotracer 152/151Eu between aqueous sodium oxalate (Na2L) solutions and toluene solutions of thenoyltrifluoroacetone (HTTA) has been studied as a function of the oxalate concentration. The pH of the aqueous phase was controlled by means of sodium acetate – acetic acid mixtures and the ionic strength (I) by NaCl or NaClO4.At low ionic strengths (~0.05) and [L] ~10−4 M EuL+ formed, but at I = 0.95 and [L] ~10−3 M EuL2− also formed. Stability constants for the 1:1 and 1:2 (metal:ligand) complexes are reported.The magnitudes of the stepwise stability constant ratios are discussed.

The distribution of thorium and a number of lanthanides between nitric acid and solutions of dibutyl butyl phosphonate in odorless kerosene has been examined as a function of the aqueous nitric acid concentration. Experiments were conducted at trace metal concentration using radioisotopes. Separation factors (denoted by S and defined as the ratio of the distribution coefficients, K, for two metal species) have been measured for some lanthanide–lanthanide couples and also for some thorium–lanthanide couples. Results indicate that separation factors between successive lanthanides (given by S = KZ+1/KZ) at the lower end of the rare-earth series are superior to those obtained with either tributyl phosphate (TBP) (D. Scargill et al. J. Inorg. & Nuclear Chem. 4, 304 (1957)) or trioctyl phosphine oxide (TOPO) (J. M. Schmitt. Oak Ridge National Laboratory. Unpublished data), but as Z increases, SDBBP ~STBP > STOPO. For thorium–lanthanide couples, S′DBBP > S′TBP. Measurements over a range of extractant concentrations indicate that the lanthanides are extracted as trisolvates.

From a study of the partitioning of the carrier-free radioisotopes Tm170, Ce144, Eu152/154, Tb160, Lu177, and Y91 between nitric acid and organic solutions containing various proportions of thenoyltrifluoroacetone (HTTA) and dialkyl alkyl phosphonates (S) in odorless kerosene, concentration equilibrium constants (k2) have been computed for the reaction[Formula: see text]where M represents a metal ion, and "w" and "o" are aqueous and organic species respectively.When used in conjunction with the data of Bronaugh and Suttle, the equilibrium constants determined in this study yielded comparative equilibrium constants (k3) for the solvation process [Formula: see text]for the rare-earth metals listed.In the extraction of Sc46, however, the species extracted is dependent on the alkyl groups of the phosphonates, the butyl and 2-ethylhexyl derivatives giving mono- and di-solvates respectively.It is concluded that steric effects are dominant in these synergic systems.

Solvent extraction and radiotracer techniques have been applied to the study of metal – tartrate ion association in water at 25 °C. Trace concentrations of the radioisotopes Tb160 and Eu152/154 were equilibrated between aqueous sodium tartrate solutions and organic phases of thenoyltrifluoroacetone in toluene. The ionic strength (0.0597) and the pH (4.53) of the aqueous phase were kept constant by means of sodium perchlorate and sodium acetate.Metal complexing with the d-, dl-, and meso isomers of the ligand was examined. For all isomers two complex species were identified with metal:ligand ratios of 1:1 and 1:2, and stability constants for both stages of ion association have been estimated. No third (1:3) complex was detected.Metal coordination numbers and the formation of tartrate–tartrate hydrogen bridges in the 1:2 complex are discussed.