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Impacts of aircraft deicer and anti-icer runoff on receiving waters from Dallas/Fort Worth International Airport, Texas, U.S.A.

From October 2002 to April 2004, data were collected from Dallas/Fort Worth (DFW) International Airport (TX, U.S.A.) outfalls and receiving waters (Trigg Lake and Big Bear Creek) to document the magnitude and potential effects of aircraft deicer and anti-icer fluid (ADAF) runoff on water quality. Glycol concentrations at outfalls ranged from less than 18 to 23,800 mg/L, whereas concentrations in Big Bear Creek were less because of dilution, dispersion, and degradation, ranging from less than 18 to 230 mg/L. Annual loading results indicate that 10 and 35% of what was applied to aircraft was discharged to Big Bear Creek in 2003 and 2004, respectively. Glycol that entered Trigg Lake was diluted and degraded before reaching the lake outlet. Dissolved oxygen (DO) concentrations at airport outfalls sometimes were low (<2.0 mg/L) but typical of what was measured in an urban reference stream. In comparison, the DO concentration at Trigg Lake monitoring sites was consistently greater than 5.5 mg/L during the monitoring period, probably because of the installation of aerators in the lake by DFW personnel. The DO concentration in Big Bear Creek was very similar at sites upstream and downstream of airport influence (>5.0 mg/L). Results of toxicity tests indicate that effects on Ceriodaphnia dubia, Pimephales promelas, and Selanastrum capricornutum are influenced by type IV ADAF (anti-icer), not just type I ADAF (deicer) as is more commonly assumed.

Aircraft↗

Preanalytical phase in coagulation testing: state of the art in the laboratories of the Piedmont region, Italy.

The control of preanalytical variables is critical, particularly for coagulation assays, since this has a direct influence on the quality of results and on their clinical reliability. The aim of the study was to evaluate the extent of information about preanalysis in the laboratories of a large region of northern Italy that perform tests of haemostasis. A questionnaire was sent concerning the number of coagulation analyses per year, the system of blood drawing, the anticoagulants and the tubes in use, the amount of blood collected, the tendency to reject unsuitable specimens, the storage temperatures, the times between collection and analysis, the conditions of tube centrifugation and identification, and the presence of staff specifically occupied in coagulation testing. Complete answers were offered by 136 laboratories (81%; 69 private and 67 public) that reported a total amount of 3,648,000 determinations per year. Statistical analysis was carried out on the findings of the investigation, in order to assess their significance and to detect possible correlations between the variables under consideration. The results show significant attention being given by laboratories to the preanalytical phase. This is also indicated by the large percentage of complete answers obtained. Some of the important positive aspects shown in the study are: (1) the preference for the closed system for blood sampling; (2) the prevalent use of primary tubes for testing; (3) a strong tendency to reject incorrect samples for analysis. On the other hand, a major problem seems to lie in the delay, particularly in some big centres, in processing of specimens, which can be critical for the correct performance of coagulation assays. The data obtained reflect with good reliability the overall situation in coagulation-testing laboratories in northern Italy.

Anticoagulants↗

Endothelin-converting enzyme activity in human cerebral circulation.

OBJECTIVE: An increased level of endothelin (ET)-1 seems to be involved in the development of augmented cerebrovascular resistance in different pathological conditions, most notably vasospasm after subarachnoid hemorrhage. Therefore, interfering with the ET synthesis or ET receptor blockade may be a promising approach in the treatment of cerebral vasospasm after subarachnoid hemorrhage. Although the receptors mediating the effects of ET-1 human cerebrovasculature are well characterized, data concerning the functionally relevant ET-converting enzyme (ECE) activity are scarce. METHODS: ECE activity was determined in organ bath studies by the use of intraoperatively harvested human pial arteries. The level of ECE activity was analyzed by comparing the shift in the concentration effect curves obtained for ET-1 and its precursor, big ET-1. In addition, the presence of ECE-1alpha immunoreactivity was studied in human cerebral tissue. RESULTS: ECE-1alpha immunoreactivity was found, although not consistently, in human cerebral arteries and was restricted to the endothelium. In isolated pial arterial segments, ET-1 and big ET-1 induced concentration-related contractions with mean pD(2) values of 9.25 +/- 0.34 and 7.13 +/- 0.17, respectively, yielding a 123-fold shift of big ET-1 versus mature ET-1. Preincubation with phosphoramidon (10(-4) mol/L) resulted in a small yet significant inhibition of the contraction induced by big ET-1. CONCLUSION: The results of our study indicate the presence of functional ECE activity and ECE-1alpha immunoreactivity in human cerebral arteries. Furthermore, the data suggest the presence of ECE-like activity that differs from that of ECE-1alpha.

Adult↗

[Re-evaluation of Tsuji's psycholexical study in terms of the Big Five personality factors].

The purpose of this study is to evaluate the psycholexical study by Tsuji (2001) in terms of the Big Five personality factors. First, the study by Tsuji is described after reviewing shortly the history of psycholexical studies in Japan, and the need for the re-evaluation of his result by confirmatory factor rotation is stressed. Second, after obtaining the Factor Parsimony solution for Tsuji's psycholexical data, the application of the orthogonal incomplete procrustes factor rotation method discussed by Browne (1972) and Kashiwagi (1989) is proposed. Finally, the result is examined in terms of the Big Five personality traits. Although some differences appeared compared to the past works in Japanese adjectives for personality traits, the Big Five personality factors hypothesis has been confirmed through the present work in the sense of the markers discussed by Goldberg (1992).

Personality↗

Supine position in labor and associated fetal heart rate changes.

Presented is an investigation of the relationship of fetal heart rate (FHR) deceleration and position of the patient in labor. In a group of 902 laboring patients, 126 (14%) demonstrated late decelerations. Of the 126, 24 (19%) patients demonstrated late decelerations in the supine position only. These occurred during uterine contractions and were associated with reduced femoral arterial blood pressure and amplitude of the capillary pulse of the big toe. A drop in capillary blood pH of the fetal scalp could also be demonstrated. These effects reproducibly appeared and disappeared when supine and lateral positions were alternated. These data would suggest that maternal aortic compression by the pregnant uterus plays a role in the etiology of fetal stress as expressed by changes in fetal heart rate and acid base balance. This effect can be evaluated and monitored simply by recording the pulse pressure of the big toe and femoral arterial pressure. These atraumatic procedures can be applied to any patient.

Aorta, Abdominal↗

[Cholelithiasis. Post-choledochostomy intraductal pressure (without and with sphinctero-infundibulostomy].

In 72 patients operated on for lithiasis of the main biliary duct (MBD), the intraductal pressure was measured through the choledochostomy T-tube. This measure was done, both in upright and lying positions, fasting and after lunch. Two groups were considered: A (of 52 cases) and B (of 20 cases). In both groups a choledochotomy was performed, and only in group B a long, although partial, sphincterotomy was also done. Three patients in group B had the upper part of the sphincter of Oddi (SO) dilated by big stones. 1) When groups A and B were compared, no significant differences of pressures in MBD was found. 2) Highly significant differences (p = 0.0001) were always found when paired data related to positions were compared: in the upright position pressures in MBD were higher than on the lying position. Group A, during fasting (9.90 +/- 4.1 cm H2O, in upon position, and 7.76 +/- 3.6 when lying) and group B, also at fasting (8.95 +/- 3.0 in the upright position and 6.57 +/- 3.0, when lying). The three patients included in group B with big stones impacted in the upper part of SO, showed low pressures in MBD, specially one (2 and 1 cm H2O, upright lying positions), but the group is too small have statistical significance. We conclude that the long but partial sphincterotomy does not modify significantly the pressures in MBD whether upright or lying, and when paired data related to positions were compared, upright pressures were always higher than on the lying position (p = 0.0001).

Choledochostomy↗

Studies of Root Function in Zea mays: IV. Effects of Applied Pressure on the Hydraulic Conductivity and Volume Flow through the Excised Root.

The volume flux, J(v), and the osmotic driving force, sigma big up tri, openpi, across excised root systems of Zea mays were measued as a function of big up tri, openP, the hydrostatic pressure difference applied across the root, using the pressure jump method previously described (Miller DM 1980 Can J Bot 58: 351-360). J(v) varied from 5.3% to 142% of its value in intact transpiring plants as a result of the application of pressure differences from -2.4 to 2.4 bar. The calculated hydraulic conductivity was 5.9 x 10(-4) cubic centimeters per second per bar per gram root and was independent of pressure. A model of root function similar to those appearing in the literature failed to provide quantitative accord with the data. A proposed model, which includes the effect of volume flux on the distribution of solutes in the symplasm, predicts accurately J(v) big up tri, openpi, and the xylem solute concentration as a function of big up tri, openP.

Journal Article↗

[Epidemiology and management of psychosomatic patients in Austria].

The problem of epidemiological surveys of psychosomatic patients particularly in view of their requirements and willingness for treatment is discussed. Since there are no data available for Austria data from FRG are presented. These data are compared with the provision of psychotherapeutic and psychosomatic care in Austria. In addition the provision of in-patient treatment for psychosomatic patients is presented. Whereas the outpatient provision of care for psychosomatic patients can be considered acceptable in the big cities, there is a big gap in the rural areas and smaller towns. The provision of in-patient treatment is at present well below of what is considered necessary by the ministry of social affairs. From these data a serious lack of provision of care for psychosomatic patients in Austria can be deduced.

Adult↗

Presence of endothelin-1 in porcine spinal cord: isolation and sequence determination.

We investigated the molecular forms of endothelin (ET) related peptides in porcine spinal cord by high performance liquid chromatography coupled with radioimmunoassays using three antisera raised against ET-1 and C-terminal fragments of ET-1 and big ET-1. ET-1 and its oxidized form were isolated as major immunoreactive peptides and sequenced. Furthermore, immunoreactivities like ET-3 and big ET-1(22-39) (contents: less than 8% and less than 1% of ET-1, respectively) were detected based on their chromatographic retention times and characteristics of immunoreactivity to the antisera. Big ET-1 was only scarcely detected. Immunohistochemical study showed the presence of ET-1-like immunoreactivity in motoneurons, dorsal horn neurons and dot- and fiber-like structures in the dorsal horn of lumbar spinal cord. These results indicate that ET-1 is present not only in endothelial cells but also in spinal cord, and that big ET-1 is converted into ET-1 in spinal cord by specific processing between Trp21-Val22. The data also indicate that ET-1 may act as a neuropeptide in the central nervous system.

Amino Acid Sequence↗

Importance of the phenotypic state of vascular smooth muscle cells on the binding and the mitogenic activity of endothelin.

Smooth muscle cells of the rabbit aorta, when grown in vitro, express distinguishable forms of phenotypes (contractile and synthetic). On contractile cells, ET-1 specifically bound to a single class of high affinity (KD = 128 pM) and high capacity (Bmax = 66,000 sites/cell) binding sites. But, whereas affinity of [125I]-ET-1 was not significantly affected by phenotypic modulation, synthetic cells displayed a 10-fold lower [125I]-ET-1 binding capacity than contractile smooth muscle cells. Similarly, the mitogenic effect of ET-1 on smooth muscle cells was considerably lower for synthetic than for contractile cells. The ET-1 receptor on primary cells was recognized by sarafotoxin S6b and the different ET-related peptides with an order of potency [ET-1 greater than S6b greater than ET-3 greater than Big ET-1 much greater than ET(16-21)] identical to that inducing smooth muscle cell growth. Therefore, these data indicate that the binding and the mitogenic effects of ET-1 on smooth muscle cells might be of different magnitudes depending on the phenotypic state of these cells.

Animals↗

Molecular forms of gastrin in antral mucosa of the horse.

The predominant form of gastrin in the antral mucosa of the stomach of virtually all species previously examined is the 17 amino acid peptide little gastrin (G17). This report describes the occurrence in equine antral mucosa of an immunoreactive form of gastrin with elution properties on Sephadex G-50 superfine similar to human unsulfated big gastrin (G34-I). This putative equine big gastrin was a major component of the gastrin immunoreactivity present. A second peak of activity in equine antral mucosa eluted in an identical manner to human little gastrin (hG17-I). Inhibition curves of equine big and little gastrin, with the gastrin radioimmunoassay utilized in this study, were parallel. This observation indicates that there was no spurious increase in the apparent relative amount of big gastrin due to significant differences in the RIA antibody cross-reactivity to big and little equine gastrin. The equine big gastrin peak was resolved by ion exchange chromatography into unsulfated and sulfated forms in approximately equal amounts. This data implies that posttranslational processing of gastrin in horses may differ from that of species previously studied.

Animals↗

Molecular phylogeny and evidence for an adaptive radiation of geophagine cichlids from South America (Perciformes: Labroidei).

Nucleotide sequences from the mitochondrial ND4 gene and the nuclear RAG2 gene were used to derive the most extensive molecular phylogeny to date for the Neotropical cichlid subfamily Geophaginae. Previous hypotheses of relationships were tested in light of these new data and a synthesis of all existing molecular information was provided. Novel phylogenetic findings included support for : (1) a 'Big Clade' containing the genera Geophagus sensu lato, Gymnogeophagus, Mikrogeophagus, Biotodoma, Crenicara, and Dicrossus; (2) a clade including the genera Satanoperca, Apistogramma, Apistogrammoides, and Taeniacara; and (3) corroboration for Kullander's clade Acarichthyini. ND4 demonstrated saturation effects at the third code position and lineage-specific rate heterogeneity, both of which influenced phylogeny reconstruction when only equal weighted parsimony was employed. Both branch lengths and internal branch tests revealed extremely short basal nodes that add support to the idea that geophagine cichlids have experienced an adaptive radiation sensu Schluter that involved ecomorphological specializations and life history diversification.

Animals↗

For enzymes, bigger is better.

Previously published data are re-examined in order to address two fundamental questions concerning enzyme catalysis: Why are enzymes so big? How is the substrate binding energy realized in the transition state? Relationships are shown that demonstrate (1) an increased enzyme:substrate mass ratio is associated with greater stabilization of the transition state and with increased substrate binding energy, and (2) tighter substrate binding is associated with greater transition state stabilization. It is argued that the conventional view of enzyme catalysis cannot account for these trends while the Shifting Specificity Model can. It is postulated that enzymes have evolved to be massive so that the interaction of the substrate with the active site alters the global conformation of the enzyme in a meaningful way; that is, the interaction alters the active site from an initial substrate-specific geometry to a transition state-specific geometry. It is also postulated that strong enzyme-substrate interactions better facilitate this active site transformation, thus, providing a mechanism for the realization of the substrate binding energy in the transition state of the chemical transformation.

Catalysis↗

Benchmarking methods for measuring biosynthetic gene cluster similarity and determination of gene cluster families.

MOTIVATION: Natural products are often produced by a set of biosynthetic enzymes that are encoded by genes clustered together in the producer's genome, referred to as a biosynthetic gene cluster (BGC). The ability to compare and cluster BGCs is essential for several applications, including predicting which bacteria will make a known product and assessing the potential diversity of natural products produced by a set of bacteria. There are multiple methods for comparing and clustering BGCs based on their similarity, but there has been a lack of investigation into how strongly BGC similarity relates to product structural similarity and how these methods perform relative to each other. RESULTS: Using publicly available databases, we developed a benchmark dataset to assess how well different BGC similarity metrics correlate with the structural similarity of their products and how well these methods cluster BGCs. We found that all methods showed moderate correlation between BGC and structural similarity, with correlations improving for more similar BGCs and varying significantly by BGC biosynthetic class. Analysis of outliers revealed some outliers were due to mistakes or omissions in public datasets, while others represented deviation between BGC similarity and product structural similarity. All methods generally performed better on clustering metrics, with BiG-SCAPE performing the best after errors in the public datasets had been corrected. AVAILABILITY AND IMPLEMENTATION: Scripts and data required to reproduce the results are available at https://github.com/aswalker-lab/BGC-clustering-benchmark and processed similarity, clusters, and scaffolds are also available at https://huggingface.co/datasets/allie-walker/BGC-clustering-benchmark. Code is also available at Zenodo: 10.5281/zenodo.17373546.

Multigene Family↗