Explicit solutions of two-point boundary value operator problems

1988

Soit H un espace de Hilbert, complexe, separable et soit L(H) l'algebre de tous les operateurs lineaires bornes sur H. On etudie des conditions d'existence non triviales pour le probleme aux valeurs limites operateurs: t 2 X (2) +tA 1 X (1) +A 0 X=0; M 11 X(a)+N 11 X(b)+M 12 X (1) (a)+N 12 X (1) (b)=0, M 21 X(a)+N 21 X(b)+M 22 X (1) (a)+N 22 X (1) (b)=0, 0<a≤t≤b ou M ij , N ij , pour 1≤i, j≤2 et A 0 , A 1 sont des operateurs de L(H). Sous certaines hypotheses concernant l'existence des solutions d'une equation operateur algebrique X 2 +B 1 X+B 0 =0, on obtient des solutions explicites au probleme aux limites

In vivo hypotensive activity ofPistacia lentiscus L

1988

The present studies were undertaken to explain the mechanism of action of the hypothesive effect of Pistacia lentiscus L. aqueous extract. The potassium, calcium and magnesium content of the aqueous extract was determined and synthetic mixtures of salts evaluated in rats. The urinary excretion volume and the sodium and potassium concentrations in urine were also determined. In an effort to explain the effects of the extract, in vivo pharmacological experiments were conducted.

Quantitative Coronary Angiography and Digital Densitometric Perfusion Measurements?How to Assess the Success of Intracoronary Balloon Dilatation

1988

Densitometric evaluation of digital subtraction angiocardiograms allows the assessment of local myocardial perfusion before and after pharmacological stimulation of coronary flow reserve during the catheterization procedure. This report deals with a case of a severe stenosis of the left coronary artery in which PTCA was regarded successful based on an appropriate increase in luminal diameter while an intima and media dissection at the dilatation site was documented. The perfusion measurements, however, pointed out a clear impairment of poststenotic myocardial perfusion after PTCA.

17O NMR study of chlorinated anisoles

1988

The 17O NMR chemical shifts of anisole and all 19 chlorinated anisoles measured in CDCI3 at ambient temperature show a dispersion of approximately 40 ppm. The substituent chemical shifts (SCS) of di- or more highly chlorinated compounds cannot be reproduced by addition of single substituent effects. Theoretical calculations of the 17O NMR chemical shifts have been attempted by molecular mechanical and semi-empirical molecular orbital methods at the INDO level, but the results are not satisfactory.

La geometria asintotica delle foglie « eccezionali » delle foliazioni di Anosov

1988

On considere les feuilletages d'Anosov de T1S, avec S surface hyperbolique fermee, et on etudie la geometrie asymptotique des feuilles « exceptionnelles ».

Changes of the renin-angiotensin and of the kallikrein-kinin system after administration of saline, christalloid and colloid solution in the rat. Eff…

1988

Some geometric consequences of the Weitzenböck formula on Riemannian almost-product manifolds; weak-harmonic distributions

1988

On demontre des consequences geometriques obtenues a partir de certaines relations lineaires entre invariants lineaires de variete de Riemann presque-produit. On definit et on etudie des distributions faible-harmoniques

Nuclear structure of97Y in the interacting boson-fermion model

1988

Unique-parity states of97Y are studied in the framework of the interacting boson-fermion model (IBFM). Spin assignments for the levels of the unique-parity yrast band are proposed on the basis of nuclear systematics and the IBFM band pattern associated with coupling of a particle-type quasiparticle (g9/2) to the SU(5) core3896Sr58. The good fit of the experimental data with the IBFM calculations confirms the single particle character of this immediate neighbour of the doubly sub-magic nucleus96Zr.

Die Wirkung von Säure und Aluminiumionen auf den Nährelementgehalt und den histologischen Zustand nichtmykorrhizierter Fichtenwurzeln (Picea abies [L…

1988

Dreijahrige Fichten wurden 2 Jahre lang in einer Spruhhydrokultur gehalten und anschliesend 6 Monate lang mit Nahrlosungen behandelt, die den Lysimeterlosungen unter Fichte im Solling entsprachen, wobei die pH-Werte auf 5.0, 3.5 und 2.5 eingestellt wurden. Ein Teil der Nahrlosungen mit pH 3.5 bzw. 2.5 wurde mit 1 oder 2 mmol Aluminium pro Liter angereichert. Die Ca- und Mg-Werte der Nadeln und Wurzeln sanken unter Saure- und Aluminiumseres nicht unter die Mangelgrenzen, auch wenn die Gehalte beider Elemente um bis zu 35% abnahmen. Weitere Veranderungen wurden fur Kalium, Phosphor und Aluminium beobachtet.

Evaluation of polysialic acid in the diagnosis of Wilms' tumor. A comparative study on urinary tract tumors and non-neuroendocrine tumors.

1988

The polysialic acid moiety of the neural cell adhesion molecule has been shown to represent an onco-developmental antigen which can be detected in both embryonic human kidney and Wilms’ tumor but not in normal adult human kidney. In the present comparative study, Wilms’ tumors, clear cell (bone-metastasizing) sarcomas of kidney, cystic nephromas, renal cell carcinomas, transitional cell carcinomas and papillomas of the renal pelvis, ureter and urinary bladder (as well normal transitional epithelium from these regions), Ewing sarcomas, hepatoblastomas, rhabdomyosarcomas, and carcinomas of the stomach, colon, exocrine pancreas, lung, and esophagus, were investigated immunohistochemically for …

The role of electromagnetic form factors in meson exchange currents

1988

The question of electromagnetic form factors, i.e. F1V versus GEV, to be used in isovector meson exchange currents in nonrelativistic calculations is critically reviewed. None of the various arguments given earlier in favour of F1V have been found valid. Furthermore, model dependence of theoretical calculations on deuteron threshold disintegration due to e.m. form factor fits and potential models is found to be substantial. In view of these results, relativistic effects have to be included for a clear understanding of this process in the high momentum transfer region.

Asymptotic paths for subsolutions of quasilinear elliptic equations

1988

Letu be an entire lower semicontinuous subsolution to the quasilinear elliptic equation divA(x,∇u)=0 in ℝn. It is shown that ifu is not bounded above, then there exists a path going to infinity along whichu tends to infinity. The result extends works of Talpur, Fuglede, and others. Growth aspects of subsolutions are also studied.

61Ni Mössbauer study of the surface hyperfine magnetic field in nickel

1988

61Ni Mossbauer measurements have been performed at 4.2 K on spherical Ni particles with an average diameter of 100 and 30 A, covered with a protective layer of SiO. Their spectra contain a surface component with a significantly reduced hyperfine magnetic field as compared with the field in the bulk. This result confirms recent theoretical predictions.

Patterns of expression of trichocytic and epithelial cytokeratins in mammalian tissues

1988

Abstract Cells forming hair and nail material are characterized by the synthesis of members of a particular group of α-keratin polypeptides (trichocytic cytokeratins, “T cytokeratins”) different from epithelial cytokeratins (“E cytokeratins”). As the precursor cells to trichocytes are derived from fetal epidermal keratinocytes expressing only E cytokeratins, we have studied the patterns of expression of both T and E cytokeratins in developing human hair-and nailforming tissues of different fetal stages, by immunocyto-chemistry using antibodies specific for certain T or E cytokeratins and by two-dimensional gel electrophoresis and immunoblotting. In developing hair follicles up to the early …

Mass spectra of methoxychlorobenzenes (chloroanisoles)

1988

Electron impact mass of all 19 ring-substituted chloroanisoles have been investigated. The fragmentation pathways were elucidated with the aid of the 1st field-free region metastable ions. The greatest disparity between the spectra of the positional isomers is shown with the [M−CH 3 ] + and [M−CH 2 O] +• ions, i.e., the ortho and para isomers preferentially lose • CH 3 , whereas the meta isomers generally show both loss of • CH 3 and elimination of formaldehyde, the latter process being more dominant with the meta-monochloro and di- and trichloro isomers having two meta-chlorine atoms. Characteristic for all isomers is also the abundant M +• and [M−CH 3 −CO] + ions, the other fragmentation …

The metabolism of mono-(2-ethylhexyl) phthalate (MEHP) and liver peroxisome proliferation in the hamster.

1988

This study has investigated the in vivo metabolism of mono-(2-ethylhexyl) phthalate (MEHP), the initial metabolite of di-(2-ethylhexyl) phthalate in mammals, and the hepatic peroxisome proliferation induced by this compound following multiple oral administration to hamsters. Hamsters received [14C]-MEHP, by gavage, at doses of 50 and 500 mg/kg body wt on each of three consecutive days. Urine was collected every 24 hours and metabolite profiles were determined using capillary gas-chromatography. Multiple high doses of MEHP (500 mg/kg) induced a change in the relative proportions of metabolites produced. As previously reported for the rat, metabolites derived from sequential ω-following by β…

Processing requirements for the recognition of insulin fragments by murine T cells.

1988

In this study we investigated aspects of antigen processing using insulin and insulin A chain-derived fragments as model antigens in Ab alpha Ak beta-restricted T-cell stimulation. Similarly to other proteins, the immunodominant region of insulin recognized by these T cells is limited in size. It is located on the insulin A chain and encompasses a portion of the molecule that is represented faithfully by peptide A1-14(SSO3-)3. Efficient presentation of intact insulin and its entire A chain is dependent on uptake and processing by APC. Whereas peptides stemming from various globular proteins are known to be presented to T cells by APC without requiring processing, this is not the case with A…

Anabolic-Androgenic Steroid Effects on Endocrinology and Lipid Metabolism in Athletes

1988

As exhaustive reviews concerning hormonal alteration (Bunt 1986) and lipid metabolism (Goldberg & Elliot 1987; Hurley & Kokkinos 1987) during normal physical exercise and training have recently been published in the Journal, this article is designed to focus only on the biological actions of synthetic anabolic-androgenic steroids on endocrinology and lipid metabolism and the interactions between both of these during training in adult male athletes.

On the metal distribution in the system GeTe−Sb2Te3

1988

The structures of GeSb2Te4, Ge2Sb2Te5 and GeSb4Te7 are not determined completely by means of classical X-ray or electron diffraction studies. We have measured the Mossbauer parameters of121Sb in these compounds as well as in their binary constituent Sb2Te3 as an attempt to improve our knowledge on the question.

Measurement of the electronicgfactor ofH2+

1988

Ion trapping and spin-dependent charge-exchange techniques were used to determine the electron g factor of ${\mathrm{H}}_{2}^{+}$ as a first step to provide a precise test of the theory of molecular g factors. Accessible to us were the vibrational states 4, 5, and 6. Averaged over these vibrational states we obtain g(v=4,5,6) =2.002 2837(18) 7(18) in agreement with the corresponding theoretical value of g=2.002 282 8(8). As a by-product we have measured the rotational g factor to be ${g}_{\mathrm{rot}=0.920(40)}$, compared with the calculated value of ${g}_{\mathrm{rot}=0.9244}$.

Nigral control of hippocampal epilepsy: a dopaminergic hypothesis

1988

The Origin of Life: More Questions Than Answers

1988

AbstractMore than 30 years of experimentation on the origin of life in the fields of chemical and molecular evolution have led to a better perception of the immensity of the problem of the origin of life on Earth rather than to its solution. At present all discussions on principal theories and experiments in the field either end in stalemate or in a confession of ignorance. New lines of thinking and experimentation must be tried. The continued exploration of our solar system, especially a better knowledge of Mars and Venus, of comets and carbonaceous meteorites may also lead to a better understanding of the prebiotic environment on Earth and will thus help us to design more appropriate preb…

La prehistoria de Ibiza y Formentera: estado actual de la investigación

1988

The study of the prehistory of Ibiza and Formentera, the two small islands that form the Pityussae sub-group within the Balearic archipelago, began a few years ago as a consequence of the discovery and excavation of the megalithic chamber tomb of a Ca Na Costa on Formentera. Before then, prehistorians were still in doubt as to whether these islands had been occupied before the Phoenician colonisation. Many sites have come to light in the last decade, allowing us to present for the first time a general survey of the prehistoric settlement of the islands. Nevertheless, many problems are still unsolved, and new excavations are needed to establish the apparently complex cultural sequence, which…

Studies on Holothuriapolii (echinodermata) coelomocyte lysate II. Isolation of coelomocyte hemolysins

1988

The lytic activity of the Holothuria polii coelomocyte lysate resides in two electrophoretically distinct hemolysins identified as He1 and He2. He1 represents the calcium dependent, heat-labile component whereas He2 is calcium independent and heat-stable. The two hemolysins share serological identity. Both hemolysins appear as single protein molecules of 80KDa molecular weight by SDS-PAGE and transblotting analysis under non-reducing conditions. However under reducing conditions, they are doublets of 76 and 80KDa molecular weight. The hypothesis that the two hemolysins could be isoforms is discussed.

Photosynthesis and transpiration of healthy and diseased spruce trees in the course of three vegetation periods

1988

CO2- and H2O-gas exchange of 20- to 25-year-old spruce trees from a plantation in the Hunsruck mountains were investigated over a period of 3 years. All measurements were made as pair comparisons, i.e., in each case the gas exchange of a damaged tree and of a relatively healthy tree in its immediate vicinity was measured simultaneously. A second plantation in the Westerwald mountains consisted of 18-year-old apparently healthy spruce trees. Pair comparison at this location meant comparison of two healthylooking trees. The investigations at both locations included diurnal course measurements of photosynthesis and transpiration, and light saturation curves and CO2-saturation curves of photosy…

Malignes fibröses Histiozytom

1988

Malignant fibrous histiozytoma (MHF) is a pleomorphic sarcoma of ubiquituous origin. The clinical and radiological features of the tumor are illustrated by 23 patients with MFH of soft tissue and 4 MFH of bone. On conventional radiography MFH appears as a soft tissue tumor, sometimes with bone involvement; on sonography it is usually non-homogeneous and hypoechogenic with areas of necrosis. On CT the masses are homogeneous or inhomogeneous (10-60 HU.) containing areas of decreased density. Contrast enhancement was about 10-20 HU. Angiographically the tumor appears as hypo- or hypervascular with pathologic vessels. The morphology of MFH in diagnostic imaging including magnetic resonance tomo…

When a compliance without pressure strategy fails due to a minority dissenter: A case of “behavioral conversion”

1988

While a strategy of compliance without pressure (Joule, 1987) had the effect of inducing almost all of a group of smoking subjects to stop smoking first for 18 hours then for 3 days, simply observing someone (an accomplice) break his or her own initial agreement to abstain from smoking for 18 hours was enough to bring about a substantial reduction in the willingness of other subjects to later abstain for 3 days. However, subjects did not follow the lead of the accomplice immediately, and persisted in their agreement to abstain for 18 hours. This pattern of indirect, but not direct influence, suggests that there may be a type of minority influence at work here that represents a sort of behav…

Study of the interaction of [Cu(bipy)]2+ with oxalate and squarate in aqueous solution

1988

A study of the formation of complexes between [Cu(bipy)]2+ and ox2− and sq2− in aqueous solution, (bipy being 2,2′-bipyridine and ox2− and sq2− the dianions of ethanedioic acid and 3,4-dihydroxy-3-cyclobutene-1,2-dione, respectively), has been carried out with the aim of comparing the coordinating properties of these related ligands. The constants of the equilibria (i) and (ii) $$[Cu(bipy)]^{2 + } + ox^{2 - } \rightleftharpoons [Cu(bipy)ox]$$ (i) $$[Cu(bipy)]^{2 + } + sq^{2 - } \rightleftharpoons [Cu(bipy)sq]$$ (ii) have been determined by potentiometry and spectrophotometry at 25.0°C and 0.1 M NaNO3:logβ=5.78(2) and 2.16(2) for the oxalato- and squarato-complex, respectively. Such differen…

Intercalated cells as a probable source for the development of renal oncocytoma

1988

Renal oncocytoma is a distinct type of epithelial tumor said to arise from the collecting duct system. Here we show that in nine of ten oncocytomas the tumor cells expressed an analog of the erythrocyte anion exchanger band 3. In the normal kidney band 3 is confined to the basolateral surface of the majority of intercalated cells which comprise up to 50% of the cortical collecting duct epithelium. Carbonic anhydrase c is another protein abundant in intercalated cells, and this was also expressed in six of the ten oncocytomas investigated. Immunoreactivity specific for band 3 and carbonic anhydrase c was not detected in any of the 20 renal cell carcinomas examined. At favourable section plan…

Etude en temps réel de la production eEcrite chez des enfants de sept et huit ans

1988

Cette recherche a pour but d’etudier la production ecrite en temps reel chez l’enfant de 7 et 8 ans (CE1 et CE2). On a demande a 12 enfants de 7 ans et a 12 de 8 ans de rediger deux textes-un recit et un compterendu- et on les a filmes en train d’ecrire. On a ensuite etudie les caracteristiques temporelles de leurs compositions: debits, pauses… Nous observons trois phenomenes importants:

A-superharmonic functions and supersolutions of degenerate elliptic equations

1988

Does velocity of dilatation influence the result of dilatation? A postmortem study.

1988

We evaluated the influence of velocity of dilatation on the success of and the vascular damage produced by dilatation. Nonatheroslerotic segments of distal superficial femoral arteries were dilated "fast" (n = 69) or "slow" (n = 45) under standard conditions with balloon catheters. The arterial wall was overstretched between 1% and more than 60%. The success of dilatation rose continuously with increasing overstretching during dilatation. The damage to the arterial wall by dilatation increased discontinuously with increasing overstretching. Dilatation success and damage patterns did not differ in the "slow" and "fast" groups.

Production ofD, D * andD s mesons in 200 GeV/c ?? K ? andp-Si interactions

1988

The NA 32 experiment at the CERN SPS has collected 38 million hadronic interactions with incident 200 GeV/c π−,K− andp beam. Using a segmented silicon active target and a telescope of high resolution silicon microstrip counters we have selected fully reconstructedD0→K−π+,D0→K−π+π+π−,D+→K−π+π+,Ds+→K−K+π+π+ and charge conjugate decays. The integrated cross-sections forDo,D+D*+ andDs+ meson production and the dependence of the cross-section on longitudinal and transverse momentum of theD are presented.

Head-twitch and forepaw-shake responses after single and repeated treatment with rolipram: interaction with noradrenergic and dopaminergic agonists a…

1988

Organoselenum chemistry I. Functional Group Transformations. Von A. Krief und L. Hevesi. Springer, Berlin 1988. XI, 221 S., geb. DM 186.00. – ISBN 3-…

1988

The human chromophobe cell renal carcinoma: its probable relation to intercalated cells of the collecting duct.

1988

In the present study we have examined ten cases of the chromophobe type renal cell carcinoma. This type of tumor is distinguished from the other carcinomas of the kidney with light cytoplasm (formerly called “hypernephroid”) by (a) a positive Hale’s iron colloid stain of the cytoplasm, (b) the occurrence of numerous invaginated vesicles within the cytoplasm that resemble the invaginated vesicles of intercalated cells of the collecting duct system, and (c) a positive immunoreaction of both the plasma membrane and the cytoplasm with antibodies to the epithelial membrane antigen (EMA) and carbonic anhydrase C (CAC), respectively. Unlike oncocytomas, which also express CAC and EMA, the chromoph…