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Simple expressions are presented to determine if a binary system will exhibit a minimum or maximum boiling azeotrope using conventional free energy calculations using molecular simulation or electr...

The SMx (x = 12, 8, or D) universal solvent models are implicit solvent models which using electronic structure calculations can compute solvation free energies at 298.15 K. While solvation free energy is an important thermophysical property, within the thermodynamic modeling of phase equilibrium, limiting (or infinite dilution) activity coefficients are preferred since they may be used to parameterize excess Gibbs free energy models to model phase equilibrium. Conveniently, the two quantities are related. Therefore the present study was performed to assess the ability to use the SMx universal solvent models to predict limiting activity coefficients. Two methods of calculating the limiting activity coefficient where compared: (1) the solvation free energy and self-solvation free energy were both predicted and (2) the self-solvation free energy was computed using readily available vapor pressure data. Overall the first method is preferred as it results in a cancellation of errors, specifically for the case in which water is a solute. The SM12 model was compared to both the Universal Quasichemical Functional-group Activity Coefficients (UNIFAC) and modified separation of cohesive energy density (MOSCED) models. MOSCED was the highest performer, yet had the smallest available compound inventory. UNIFAC and SM12 exhibited comparable performance. Therefore further exploration and research should be conducted into the viability of using the SMx models for phase equilibrium calculations.

Soil fertility is the basis for production of high green mass, which has numerous essential benefits in urban areas. This study aimed to investigate the soil fertility of urban land. This was done by comparing soils from a vegetable garden and its surrounding arable land. A local brickwork dump was included. The soils were Hortisols, slightly stagnogleyic Luvisols, and a Regosol from sandy loamy silt. The location of the study was in the center of one of the world’s largest urban, hard-coal mining and heavy industry areas, the Ruhr area in Germany. The investigations for identifying the characteristic features of the soil fertility involved determination of the profile horizons, texture, pH, bulk density, C/N ratio, content and stocks of organic carbon, total nitrogen, available phosphorus and potassium, and soil water by field capacity. As they are expected to become construction land, the sites were already in a derelict state. The results show that all three soil types had high fertility characteristics. However, the fertility of the garden soils was much greater than that of the local arable land. This was due to the strong and deep accumulation of organic carbon due to compost application. The available phosphorus and potassium contents and field capacity were also distinctly increased in the garden soils. The spatial distribution and distribution with depth of pH, bulk density, organic carbon, nitrogen, available phosphorus, and potassium were extremely heterogeneous among the individual garden soils. In contrast, in the arable land, they were uniform. The organic carbon accumulation in the dump was in the range of that of the garden soils, but the nutrient contents were lower. These results show that the diversity of properties of urban soils is much higher than that of arable soils. The dereliction of arable, garden, and dump soil and vegetation by bushes and trees also affect the soil properties. There should be greater awareness of the high fertility of urban soils, such as vegetable garden soils. Vegetable garden soils have a high potential for contributing to solving urban problems by producing high volumes of biomass and storing water. Therefore, it should be demanded that vegetable garden soils receive a high protection status, and they should not be used for the establishment of construction.

Background Berberis orthobotrys Bien ex Aitch. (Berberidaceae) is a plant indigenous of Pakistan that is locally used for the treatment of hypertension. Hypothesis This study evaluated the vasoactive properties of a Berberis orthobotrys root extract and its fractions, and investigated the role of the endothelium and the underlying mechanism. Study design An aqueous methanolic extract of Berberis orthobotrys roots was prepared and submitted to a multi-step liquid-liquid fractionation with solvents of increasing polarity. Vascular reactivity of the different fractions was assessed using porcine coronary artery rings either with or without endothelium, and in the presence or absence of specific pharmacological tools. The ability of Berberis orthobotrys extracts to affect phosphodiesterase (PDE) activity was evaluated using a radioenzymatic method and purified phosphodiesterases. Results The aqueous methanol extract induced similar relaxations in coronary artery rings with and without endothelium, and, amongst the three derived preparations, the butanol fraction (BFBO) was slightly but significantly more effective than the ethyl acetate fraction and the aqueous residue in rings without endothelium. Analysis of the butanol fraction (BFBO) by LC-ELSD-MS indicated the presence of four major isoquinoline alkaloids including berberine. BFBO significantly potentiated the relaxations induced by cyclic GMP- and cyclic AMP-dependent relaxing agonists, and inhibited contractions to KCl, CaCl2, and U46619 in endothelium denuded rings. In contrast, BFBO did not affect relaxations to endothelium-dependent vasodilators. BFBO concentration-dependently inhibited the cyclic GMP-hydrolyzing activity of basal PDE1, calmodulin-activated PDE1 and PDE5, and of cyclic AMP-hydrolyzing activity of PDE3 and PDE4 with IC50 values ranging from 40 to 130 µg/ml. Conclusion The butanol fraction of the aqueous methanol extract of Berberis orthobotrys roots induced pronounced endothelium-independent relaxations and inhibited contractile responses by acting directly at the vascular smooth muscle in the coronary artery. Moreover, BFBO potentiated relaxations induced by both cyclic GMP- and cyclic AMP-dependent vasodilators most likely due to its ability to inhibit several vascular PDEs, and in particular PDE4 and PDE5.

In den Beobachtungen von ADS 8119 ausert sich das unaufgeloste Untersystem nicht nur durch seine Bewegung, sondern auch merklich durch seine Storung der Bahnlage des sichtbaren Paares. Nach der Ermittlung spezieller Storungen erster Ordnung werden die visuellen und spektroskopischen Elemente und die Massen des vierfachen Sterns neu bestimmt. Die Parallaxe ist 0″.130.

Following the diversified topic of this conference, let me present a variety of comments — not all new, but resulting from a long string of stars drifting across the desk. The chase after visual orbital elements is not exactly a self-purpose but is aiming at further data, in particular, at good masses. The last published lists of high-quality mass determination represent the status of 20 years ago; but a compilation at this time would probably not last long as the progress promises to quicken.We have 1000 positional (visual/photographic/speckle) orbits, among them about 700 acceptable in the range from fair to definitive. Yet less than 10% of them give good component masses. Most of them are outside the range of parallax measures with the requisite, high precision (that unfortunatly holds for the Hyades); some frustrate the parallax measurer by displaying wedge– and peanut–shaped images, and the more exciting cases of abnormal, non-main–sequence components often cannot get good mass ratios owing to large distances or long periods.

The objective of astronomy is the exploration of all phenomena outside the Earth. Its realm is the whole of space, out to the remotest distances. Thus the astronomer is spatially separated from his research objects (except those few celestial bodies now within reach of spacecraft exploration); he cannot approach them at will in order to experiment with them. He must make his observations often at those times and under those conditions that Nature prescribes. Furthermore, the objects and the movements he has to measure in astrometric work, and the amount of light available for astrophysical analysis are usually so small that observations are subject to considerable natural uncertainty. If, in spite of all this, in speaking of the numerical conquest of celestial motions, the term astronomical accuracy has become a household word, the reason lies in the fact that these calculations can be based on a large amount of observed data and on a careful consideration of all possible sources of error.

n-Octyl-5-dithio-2-nitrobenzoic acid (ODNB), the reaction product of n-octane-1-thiol and Ellman's reagent, can be isolated in crystalline form. Like Ellman's reagent, ODNB can be used for the titration of SH groups in proteins, but with considerable advantages: Due to the absence of one negative charge and the presence of a lipophilic hydrocarbon chain, titrations of protein thiols are significantly faster. Normally, endpoints are reached after 5-30 min, while the corresponding reaction with Ellman's reagent may take 1-2 h. Another advantage of ODNB is that it finds access to thiol groups which normally remain undetected. With myosin S1, for example, ODNB reacts with a thiol group which is not reactive with Ellman's reagent. Although ODNB has detergent properties, reaction of this thiol group as a consequence of denaturation seems unlikely, because ODNB was used below its critical micelle concentration and all other thiols of myosin S1 remained buried. The n-octylthiol derivatives of proteins formed by reaction with ODNB can be used for transient protection of thiols, for example, during purification procedures, or for a reversible blocking of SH groups involved in biochemical reactions.

In a controlled clinical trial in patients admitted for general surgery (mainly abdominal and thyroid), histamine release following nalbuphine 1 mg/kg i.v. versus fentanyl 5 micrograms/kg i.v. was studied in the course of an otherwise routine induction with promethazine/pethidine as premedication 30 min before the opioids and alcuronium-flunitrazepam-thiopental 5 min later. Succinylcholine was given before intubation and further analgesia was obtained by repeated administration of either nalbuphine or fentanyl. Plasma histamine levels were measured by a specific fluorometric assay, heart rate and blood pressure were measured for assessing hemodynamics, and clinical signs of anaphylactoid reactions such as skin eruptions and arrhythmias were registered. RESULTS. Nalbuphine and fentanyl both released histamine with an incidence of more than 40%. In addition, nalbuphine potentiated the histamine release evoked by the sequential administration of alcuronium-flunitrazepam-thiopental in one complex of application. The incidence of histamine release in the nalbuphine group was 6/13 = 46%, in the fentanyl group only 1/11 = 9% (chi2 test, P less than 0.05). Furthermore, this study showed high histamine levels after succinylcholine and intubation in a relation to time of administration that suggested histamine release as a stress response to intubation. Finally, the incidence of histamine release after a second injection of the opioids was still 30%. A direct correlation between plasma histamine levels, hemodynamic changes, and skin reactions could not be shown. A detailed causality analysis with histamine release as a contributory determinant showed histamine release less detrimental to hemodynamic stability than the opposite, which had been expected. However, the promethazine administered 30 min before induction of anaesthesia had strong H1- and H2-receptor antagonistic activity and was given with optimum timing for H1- and H2-prophylaxis. CONCLUSION. The study demonstrated that histamine release during anaesthesia and surgery depends strongly on the time sequence of drugs and measures used. Histamine release is not predictable from studies in human volunteers alone; studies in patients have to be added. Histamine release is not always detrimental. H3-receptor-mediated effects after H1- and H2-prophylaxis may help patients to counteract the effects of a series of vasoactive drugs given during induction of anaesthesia.

Schon aus dem Mittelalter sind Brandschutzvorschriften uberliefert. Die Kenntnis der Rechtsentwicklung, besonders zur Zeit Preusens, ist fur das Verstandnis moderner Baugesetzgebung unumganglich. Die durch das Grundgesetz vorgegebene Gesetzgebungszustandigkeit von Bund und Landern bestimmt heute die Aufteilung In Planungs- und Bauordnungsrecht. Im Rahmen des nach Artikel 23 erfolgten Beitritts der DDR zum Geltungsbereich des Grundgesetzes wurde inzwischen auch dort neues Recht geschaffen.

Operative risks should be assessed before surgical intervention not only by heuristic means, but in addition also by quantitative methods. ASA-classification and Recovery Index (McPeek) are offered for a critical routine assessment of global perioperative risk.

10054 Background: GIST size is one of the most important prognostic markers for recurrence and poor survival. However, little information exists regarding the relationship between tumor volume and clinical outcome after treatment with IM. A phase II randomized clinical trial of two dose levels of IM (400 vs. 600 mg daily) in pts with incurable GIST was previously presented (Proc ASCO 2001; Combined GI Symp 2004 and 2007). With median follow-up of 64 months, we report additional analyses of the relationship between tumor volume and IM efficacy. Methods: Data on initial tumor bulk were prospectively collected, and 146 pts were separated into quartiles according to total tumor volume: < 39.1 cm2 (n=36), 39.1 = 102.16 cm2 (n=37), 102.16 = 262.6 cm2 (n=36), = 262.6 cm2 (n=37). Tumor bulk was correlated with standard efficacy outcomes. Results: The overall response rate (CR + PR) for all pts was 68.1% (95% CI 59.8% - 75.5%). Median time-to-progression (TTP) was 24 months, and overall survival (OS) was 57 months. The overall response rates for the four quartiles according to tumor burden (lowest to highest) were: 64%, 70%, 75%, and 65% respectively. Median TTP by quartile was: 57, 25, 18, and 17 months. Median OS for these same groups: not reached, 57, 47, and 35 months. The Kaplan-Meier estimates of patients alive at 64 months based on tumor bulk were 62%, 40%, 44%, and 31% respectively. Disease bulk was an independent prognostic factor for overall survival using a Cox regression model including sex, performance status, IM dose, gender, age, prior chemotherapy, and tumor volume, but not when baseline hemoglobin was included. Conclusions: Pts with bulky GISTs progress sooner and die more quickly than those with lesser tumor volumes, though other factors may contribute as well. Even pts with the bulkiest tumors frequently respond to treatment with IM, however. TTP for this population approaches 1.5 yrs, and median survival for these pts approximates 3 yrs. One-third of pts with extraordinarily bulky GISTs are long-term survivors. The potential relationship between baseline hemoglobin and tumor bulk requires further investigation. [Table: see text]

The distance and masses of the components of the triple star Algol (Beta Persei) are derived from photographic and electronic data collected with the two 0.76 m objectives of the Thaw Refractor at the University of Pittsburgh's Allegheny Observatory and with the 0.61 m visual refractor at Swarthmore College's Sproul Observatory. These datasets constitute the major narrow-field astrometric collections of this star. The newly derived weighted mean trigonometric parallax of Algol is now +0.0343 +/- 0.00085 corresponding to a distance modulus of 2.32 +/- 0.054 mag. The total mass of the Algol system is estimated at 6.05 +/- 0.45 solar mass. The photocentric semimajor axis of the AB/C orbit is determined in the blue, yellow, and red bandpasses of the three independent astrometric systems. The total mass for the A and B component stars is found to be 4.63 +/- 0.35 solar mass and the mass of the C component is determined to be 1.42 +/- 0.13 solar mass. Residuals to this solution showed no meaningful correlation to the orbital motion of A/B. Thus it is probable that the photocenter is located near the center of mass of the A/B subsystem. There is no evidence of a previously suggested 32 yr orbital motion and no significant acceleration is evident in the 60 yr photographic series. It is therefore unlikely that the system has a fourth stellar mass component. It is noted that the visual band interferometric studies of the Algol system have the AB and C components interchanged.

Completion of long-term astrometric plate series yields revised results on the orbits and parallaxes. The subdwarf mu Cas seems to be overluminous; the distance of the supergiant epsilon Aur is near 600 pc. The unresolved companion in the red dwarf pair BD +6degree398 is of very low mass, and the companion of BD +67degree552 massive but probably underluminous.

The visual binary containing the well-known eclipsing pair VW Cep is studied with combined visual and astrometric data: P = 29.0 yr, a = 0.428". The orbit and parallax 0.038" give masses in agreement with radial-velocity and light-curve results: 0.8, 0.3, and 0.6 solar masses, respectively.

The orbital elements of this visual binary are revised; we find a=0.91" and P=129 yr. The mass ratio measured from a 75-yr series of astrometric plates supports the spectroscopically suspected presence of a third body.

191 trigonometric parallaxes, 19 binary-star mass ratios, and three new unresolved red-dwarf binaries are listed and annotated

This system consists of three red-dwarf components with masses from 0.4 to 0.1 solar masses. The orbits with periods of 16 and 323 years are rediscussed from astrometric plates to 1991.

We present an improved orbit of the astrometric binary alpha Ophiuchi (V = 2.08, spectral class = A5 III), as derived by supplementing existing observational material from the Allegheny and Sproul Observatories covering the periods 1934-63 (A) and 1946-64 (S) with heretofore unmeasured Sproul plates covering the intervals 1965-67 and 1985-90. The combined data over 6 revolutions yield an orbit with P = 8.67 yr; the semimajor axis is alpha = 0."0.81 ± 0."005. The Sproul data yielded an absolute parallax of piabs = +0."069 ± 0."005, and the weighted mean of five independent determinations is piabs = +0."065 ± 0."004. This gives an absolute magnitude of MV = +1.2, which suggests that the more massive component of alpha Oph is a subgiant.

Astrometric measures are inconclusive concerning the suspected duplicity but make the star much overluminous.

Commission 26 has changed its name. The new denomination, warmly promoted by Dommanget, represents more adequately the actual field of the Commission Itself and appears as a good start for extending its interest beyond the traditional aspects (morphology and statistics) and plunging into problems connected with the origin, evolution, mass spectrum and dynamics of small star associations.

The report period 1982-84 was characterized by an again increased volume of material processed in data and abstracting centers, and by a growing clientele particularly of online services. The Working Groups of Commission 5 seek continued consultation with research object commissions so that the advanced documentation technology be efficiently employed toward specific demands of subject areas as to indexing, tagging, comprehensive, selective and inter-discliplinary retrievals. The guideline library for these purposes has been augmented by the First Dictionary of the Nomenclature of Celestial Objects by A. Fernandez, M.-C. Lortet and F. Spite (Astr. Astrophys. Suppl. 52 no.4, 1983) and by the Guide to the Presentation of Astronomical Data by G.A. Wilkins (CODATA Bull.46 1982); a new draft of the IAU Style Manual is before the IAU EC.