Calculation of the relative basicities of methylamines in solution

1990

Abstract The relative basicities in solution of the methylamines have been calculated using the model of Miertus, Scrocco and Tomasi to describe the solvent effect. The surface of the cavity is defined with the GEPOL method. The ab initio calculations have been performed using a 4-31G basis set. The relative order is reproduced using a combination of the gas-phase proton affinities obtained with quantum-mechanical methods by Eades, Weil, Dixon and Douglass and the solvation values obtained by us. The results seem to point out that the irregular order is not due to solvent but to basis-set effects.

Antiproton-proton annihilation at rest in H2 gas into π+ π− π0

1990

Antiproton-proton annihilation at rest into π+ π− π0 has been studied by stopping antiprotons from LEAR in a H2 gas target at normal temperature and pressure. The reaction is observed in coincidence withL X-rays which are emitted in the cascade of\(\bar pp\) atoms. The X-rays populate one of the angular momentumL=1 states of a\(\bar pp\) atom which then annihilates. A spinparity analysis of the π+ π− π0 Dalitz plot gives contributions from the threeP states from which annihilation into three pions is allowed. The most striking features of the Dalitz plot are production of charged and neutral ϱ(770) and off2(1270) mesons. Production of ϱ(770) mesons proceeds via the isoscalar part of the1P1 …

Carcinoma of the prostate. Guidelines for treatment: the role of antiandrogens.

1990

Our preliminary experience shows that flutamide is effective in patients with stage C or D prostate cancer. Local and distant response rates are comparable to those obtained with "classic" hormone therapy. Libido and sexual potency generally are unaffected. Palliation of symptoms, which is frequent, is usually accompanied by improved performance status and quality of life. Side effects are slight or moderate, but elevated transaminase levels in patients with borderline liver insufficiency are possible.

Study of low-lying states of 51V, 50,52,53Cr, 59Co and 63Cu nuclei by α-particle inelastic scattering

1990

Abstract Differential cross sections for inelastic scattering of α -particles to various levels in 51 V, 50,52,53 Cr, 59 Co and 63 Cu have been measured at incident α-particle energy of 25 MeV. Data corresponding to the odd nuclei have been analyzed in terms of the weak-coupling model and the symmetric rotor model. Even-even nuclei data have been analyzed in the framework of the coupled channels formalism in terms of two collective models: the harmonic vibrational model and the symmetric rotor model. Model predictions reproduce quite satisfactorily experimental angular distributions.

( E )‐ und ( Z )‐Enole von β‐Ketocarbonsäureamiden

1990

(E)- and (Z)-Enols of β-Ketocarboxylic Acid Amides Reaction of dimesitoyldiazomethane (1) with ammonia (3a), primary and secondary amines (3b – o and 3p – v, respectively) leads to the completely enolized amides 4a – v. Besides the chelated Z configuration the unusual E isomer exists in the most cases, too. The Z/E distribution in the equilibrium depends on the steric and electronic effects present in the amide group CONR2R3 and on the solvent.

Studies on the mechanism of photosystem II photoinhibition II. The involvement of toxic oxygen species.

1990

In a previous paper it was shown that photoinhibition of reaction centre II of spinach thylakoids was predominantly caused by the degradation of D1-protein. An initial inactivation step at the QB-site was distinguished from its breakdown. The present paper deals with the question as to whether this loss of QB-function is caused by oxygen radical attack. For this purpose the photoinhibition of thylakoids was induced at 20°C in the presence of either superoxide dismutase and catalase or the antioxidants glutathione and ascorbic acid. This resulted in comparable though not total protection of D1-protein, photochemistry and fluorescence from photoinhibition. The combined action of both the enzy…

Director orientation in chevron surface-stabilized ferroelectric liquid crystal cells. Verification of orientational binding at the chevron interface…

1990

Abstract We present results of theoretical modelling and experimental study of director distributions and the associated optical properties of chevron surface stabilized ferroelectric liquid crystal (SSFLC) cells. Chevron cells are modelled as being two stacked FLC slabs, described by distinct orientation distributions of the director [ncirc]-polarization P([ncirc] – P) couple. In each slab the [ncirc] – P distribution is governed by bulk Frank elastic and electric field-induced torques and by surface torques at the FLC-solid interface and at the chevron interface, where the two distributions are coupled. The optical properties of such structures are calculated numerically and the results t…

Erythropoietin for the treatment of anemia of malignancy associated with neoplastic bone marrow infiltration.

1990

This clinical trial was performed to study the effects of intravenously (IV) administered recombinant human (rh) erythropoietin (EPO) at escalating doses (150, 300, and 450 U/kg, administered as an IV bolus injection, twice weekly, for 6, 4, and 4 weeks, respectively) in five patients with low-grade non-Hodgkin's lymphoma (Ig NHL) and bone marrow involvement and one patient with multiple myeloma (MM). All patients were anemic due to underlying disease. None of the patients had a history of bleeding, hemolysis, renal insufficiency, or other disorders causing anemia in addition to bone marrow infiltrating malignancy. Endogenous EPO serum levels were significantly increased in all patients (7…

Temperature sensation: the "3-bowls experiment" revisited.

1990

The "3-bowls experiment", usually attributed to E. H. Weber*, will be remembered by many from their first lab course in human physiology. The left and right hands are immersed for several minutes in bowls containing water at 10 and 40°C, respectively. When both hands are then placed in a third bowl of water at 27 °C, the left hand feels distinctly warm and the right hand distinctly cool. Until now nobody has been able to reconcile this apparent unreliability of the sense of temperature with the observation that humans regularly make judgements of the temperatures of objects; for example, mothers seldom use a thermometer to check the temperature of a baby's milk, but rather hold the bottle a…

Evidence for intruder states in111Rh

1990

Levels in111Rh have been investigated via the γ -rays following the β−-decay of 2.1 s111Ru. The Ru activity was produced in the fission of249Cf and separated chemically from the fission product mixture. The emitted γ-rays were studied by γ singles and γ(t) coincidence measurements. Evidence for intruder states in111Rh has been obtained. Their properties are discussed and compared with those in the lighter Rh isotopes.

Anomalous thermoelastic behavior of (KI)1-x(NH4I)x

1990

Abstract An anomalous softening of the shear mode c 44 is observed in (KI) 1- x (NH 4 I) x with Brillouin scattering (10 K ⩽ T ⩽ 300 K ). It is caused by the weak quadrupolar moment of the NH 4 + ion, induced by the C 3 v symmetry of the potential. A parallel decrease of the lifetime of this transverse phonon at lower temperatures is observed. Static random strain fields due to admixing KI with NH 4 I are small. The results have been treated in terms of a mean field theory. The c 11 elastic constant does not show any anomalous behavior. Also are given the elastic constants c 11 and c 44 for x =0.14, 0.43 and 1 and 1 at T = 300 K and 10 K .

Observation of the decay KL→π0γγ

1990

Abstract The decay mode K L → π 0 γγ has been observed with a signal of 21 events and an expected background of 1.5±0.9 events. A branching ratio for decays with invariant γγ masses above 280 MeV of (2.1±0.6)×10 −6 is calculated. This result is compared with the values estimated from theoretical models and has implications for the CP conserving contribution to K L → π 0 e + e − decay.

Untersuchungen zur Herstellung von ZSM-5-Schalen- und Vollkatalysatoren

1990

Quantitative and qualitative analysis of DNA extracted from postmortem muscle tissues

1990

DNA extracted from 33 postmortem muscle specimens was analyzed using MZ 1.3, a hypervariable minisatellite probe, as well as locus-specific minisatellite probes (g3, MS1 and MS43). After storage at -25 degrees C for 10 months, DNA from all the samples was partially (approximately 21% of total DNA) degraded even when autopsy was performed 1 day postmortem. However, more than 90% of DNA samples up to at least 3 days postmortem were suitable to obtain good restriction fragment length polymorphism (RFLP) patterns. When small strips of specimen were stored for 8 days at room temperature in moist chambers, approximately 42% of total DNA was degraded. Only 30% of these DNA samples still showed goo…

Spermatocyte chromosome banding studies inBuccinulum corneum (Prosobranchia: Neogastropoda): Variation in silver-NOR banding pattern

1990

Diploid number (2n=72), and haploid number (n=36) forBuccinulum corneum (L. 1758) collected from the Gulf of Palermo in December 1987 were determined. A simple method to obtain nucleolar organizer regions (NOR), and constitutive heterochromatin regions (C-bands) of chromosomes ofB. corneum is described. Analyses of silver-stained chromosome preparations ofB. corneum suggest that a within-individual variability in NOR-banding pattern is present in each of the five specimens analysed.

Salmonella serovars identified at the centre for enterobacteriaceae of palermo over the 5-year period 1983-87

1990

Salmonellosis is become an increasing public health problem in many countries. Serotyping and assessment of antibiotic resistance are useful tools, which assist in understanding the epidemiology of Salmonella infections. In this respect, the Centre of Enterobacteriaceae of Southern Italy provides helpful information on the changing pattern of Salmonella serovars in this geographic area. This paper reports the distribution of serovars and their antibiotic susceptibility in the years 1983-1987. In particular, because of their peculiar trends during this 5-year period, epidemiological features of Mbandaka, Corvallis, Dublin, Infantis and Wien serovars are described.

Untersuchungen zum Agglomerationsmechanismus bei der Herstellung von extrudierbaren Tonerdepasten

1990

Martensitic phase transformation cubic-orthorhombic of NaCN and (NaCN)0.98 (KCN)0.02

1990

The ferroelastic cubic-orthorhombic transition of single crystals NaCN and (NaCN)0.98 (KCN)0.02 has been studied by x-ray diffraction. The domain configuration obtained is consistent with the Wechsler, Lieberman, Read-model for martensitic transformations.

Superconducting hollow and solid fibers and thin films of YBa2Cu3OX from a polymeric precursor

1990

LE DISRAFIE SPINALI CISTICHE: casistica e attuali orientamenti terapeutici in età neonatale

1990

Gli Autori riportano la loro esperienza sul trattamento delle disrafie spinali cistiche in età neonatale e, dopo una revisione della letteratura, ne sottolineano gli aspetti deontologici, clinici e terapeutici

Bildgebende Diagnostik der Peritonealkarzinose

1990

Two hundred and eighty-seven radiological and sonographic examinations in 142 patients with confirmed peritoneal carcinosis were evaluated retrospectively. The examinations included abdominal films (19), infusion urograms (20), contrast examinations of the intestine (26), small bowel enemas (2), double-contrast examinations of the colon (40), demonstrations with water-soluble contrast (6), sonographies (80) and CTs (96). CT and colonic double-contrast studies were complementary and valuable methods for diagnosing peritoneal carcinosis and should both be used.

Influence of culture conditions on production of flavour compounds by 29 ligninolytic Basidiomycetes

1990

The odorous volatile metabolites produced by 29 ligninolytic Basidiomycete strains (identified by gas chromatography coupled to mass spectroscopy — GC-MS) and the flavour quality of their cultures were investigated on 6 different liquid media tested with and without agitation. 113 compounds were identified, the most numerous being alcohols (2-methyl 1-propanol, 2-methyl 1-butanol, 3 methyl 1-butanol, 2 phenyl ethanol, 3,4, dimethoxy phenyl methanol, 4 vinyl phenol), aldehydes (3, 4 dimethoxybenzaldehyde) and ketones (4-hydroxy 3-methyl 2-phenyl 2-cyclopentene 1-one). One third of these compounds possessed an aromatic skeleton. The influences of medium composition and agitation conditions on…

A microplate version of the DNA-synthesis inhibition test for rapid detection of DNA-alteration potentials.

1990

A microplate version of the DNA-synthesis inhibition test (DIT) for fast detection of DNA-alteration potentials has been developed. The DIT is based on the concept that DNA damage causes inhibition of DNA synthesis that becomes detectable some time after replicating cells have been in contact with genotoxic agents. In this test procedure human tissue culture cells (HeLa S3), prelabeled with [14C]thymidine, arfe exposed for 90 min to the substances in question. After the cells are rinsed, they are allowed to recover for 2 1/2 h in fresh culture medium, thereby unspecific interactions interfering with DNA replication are practically eliminated. Next, [3H]thymidine is added for 30 min, and the…

Evaluation by reverse phase HPLC of [3H]acetylcholine release evoked from the myenteric plexus of the rat.

1990

Myenteric plexus-longitudinal muscle strips isolated from the small intestine of rats were incubated with [3H]choline to measure the synthesis and the release of [3H]acetylcholine. To separate different radioactive compounds (acetylcholine, choline, phosphorylcholine) from both the tissue and the overflow a new method, the reverse phase HPLC, was used. The radiochromatogram following the injection of a [3H]choline-standard and a [14C]acetylcholine-standard onto the HPLC showed a clear separation of both isotopes with a recovery rate of roughly 100%. Incubation of the muscle strips with [3H]choline caused the synthesis of [3H]acetylcholine (30,000 dpm/preparation) that increased 2-fold, when…

Proboscidea: a preliminary note

1990

Abstract Proboscidean remains collected during the 1983–1989 field seasons are described here. They are assigned to Deinotherium aff. levius (14 isolated teeth) and to Gomphotherium pasalarense (44 isolated teeth). No evidence was found for another subspecies described by Gaziry from Pasalar. The proboscidea are probably indicative of woodland conditions at Pasalar.

13C NMR study of aromatic ring-substituted (E)-3-phenylpropenals and (2E,4E)-5-phenylpenta-2,4-dienals

1990

13C and 1H chemical shifts together with C,H and H,H coupling constants are presented for (E)-3-phenylpropenal, (2E,4E)-5-phenylpenta-2,4-dienal and their o-OCH3- and o-, m- and p-NO2-substituted derivatives. The SCSs calculated for the aldehyde chains show similar effects on the ring carbons, except in the para position where the shorter chain causes a 3.3 ppm deshielding and the longer chain a 1.0 ppm shielding effect. This shift difference is reflected in all the ring-substituted derivatives of the two series of aldehydes, but not in the one-bond C,H coupling constants. The effect of aromatic ring substitution on 2J(C,CHO) seems to be mainly inductive in origin. The importance of the str…

Maux de l'économie, mots des économistes

1990

International audience; La méthodologie économique a largement séparé les discours (hypthèses, théorie, corps de pensée) de l'action (représentée essentiellement par les applications ou les descriptions monographiques). Dans cet essai, avec la plus large prudence répondant à une démarche balbutiante, nous tentons de donner des représentations synthétiques, sur longue période, de l'évolution de la littérature économique ; ceci au moyen des méthodes usuelles de l'analyse des données. Il reste, quelque soit les résultats auxquels nous parvenons, que ce type de traintement repose sur l'hypothèse d'avoir pris en compte chaque production de littérature comme un objet statistique simple. L'applica…

Seasonal variation of hypolaetin 8-glucoside inSideritis mugronensis borja

1990

A quantitative analysis of the antiinflammatory flavonoid hypolaetin 8-glucoside from Sideritis mugronensis during an annual growth cycle was carried out. After an irregular increase in spring, the maximum levels were reached and maintained in early summer samples.

Studies on the mechanism of photosystem II photoinhibition I. A two-step degradation of D1-protein

1990

The role of D1-protein in photoinhibition was examined. Photoinhibition of spinach thylakoids at 20°C caused considerable degradation of D1-protein and a parallel loss of variable fluorescence, QB-independent electron flow and QB-dependent electron flow. The breakdown of D1-protein as well as the loss of variable fluorescence and QB-independent electron flow were largely prevented when thylakoids were photoinhibited at 0°C. The QB-dependent electron flow markedly decreased under the same conditions. This inactivation may represent the primary event in photoinhibition and could be the result of some modification at the QB-site of D1-protein. Evidence for this comes from fluorescence relaxati…

Structure of theN=59 nucleus97Sr: coexistence of spherical and deformed states

1990

A band with a rotational pattern based on a state at 585.1 keV has been identified in theN=59 neutron-rich nucleus97Sr. Its properties lead to the [422] 3/2 Nilsson-orbital assignment for the band head. There is evidence for a second band with the head at 644.7 keV and the configuration [541] 3/2. Since the ground state and the lowest excited levels are spherical, shape coexistence is established for97Sr. A deformed nature of several levels at 500–600 keV results also from QRPA-model calculations. The structure of the low-lying spherical levels has been studied in the frame of the IBF model. The results of the present investigations lead to a better understanding of theN=59 isotones which c…

Self-consciousness Scale: a study of Spanish housewives.

1990

The purpose of this study was to examine the applicability with 93 Spanish housewives of the translated Self-consciousness Scale. We present reliability measures and normative data, and we also include data for two clinical samples (31 depressive and 31 asthmatic women patients).

The mammalian geochronology and biogeography of Paşalar (Middle Miocene, Turkey)

1990

Abstract The Pasalar fauna includes 56 mammalian species of European. Asian, African and North American origin. Evidence provided on the stage-of-evolution of the primates Sivapithecus darwini and cf. Kenyapithecus, the rodent Turkomys pasalarensis, insectivores, carnivores, rhinos, suids and ruminants suggests that Pasalar is correlative with the Late Langhian marine stage and European Mammal Neogene Zone 6., circa 15 Ma (million years ago). A review of the Pasalar fauna's biogeographic history suggests that it was aggregated by a succession of pulsed intercontinental geographic extensions tied to global sea-level lowering events during the earlier half of the Miocene.

Systematics of nuclear ground state properties inSr78–100by laser spectroscopy

1990

Hyperfine structures and isotope shifts of strontium isotopes with A=78 to A=98 and A=100 were measured by collinear fast beam laser spectroscopy. Nuclear spins, moments and changes in mean square charge radii are extracted from the data. The spins and moments of most of the odd isotopes are explained in the framework of the single particle model. The changes in mean square charge radii are compared with predictions of the droplet model and of Hartree-Fock-plus-BCS calculations. For the isotopes in the transitional regions below and above the N=50 shell closure, the inclusion of quadrupole zero point motion in the Droplet model describes part of the observed shell effect. An additional chan…

Phase diagrams of monolayers of the long chain fatty acids

1990

Non-zero chemical potential and the shape of the pT-distribution of hadrons in heavy-ion collisions

1990

Abstract The pT-spectra of negative particles from 200 GeV/nucleon O + Au and S + S collisions, measured at CERN by the NA35 collaboration, are fitted by a thermal distribution of massive pions which are strongly out of chemcial equilibrium. Both sets of data are consistent with the same values of temperature and chemical potential, T ≈ 165 MeV and μ ≈ 120 MeV. The low pT behaviour of the measured spectra seems to indicate that the transverse flow in these collisions is not strong.

Sublingual administration of captopril versus nitroglycerin in patients with severe congestive heart failure.

1990

Angiotensin-converting enzyme inhibition has proven to be a successful approach for the long-term treatment of patients with congestive heart failure. This investigation compared the acute hemodynamic changes after sublingual administration of the angiotensin-converting enzyme inhibitor captopril with those after nitroglycerin. A total of 24 patients with severe left heart failure (New York Heart Association classes III and IV) were given 25 mg captopril and 0.8 mg nitroglycerin sublingually in this randomized, cross-over study. Hemodynamic monitoring revealed a clear improvement in pre- and afterload parameters for both drugs (P less than 0.01 and P less than 0.001), while captopril induce…