Showing papers by "Bielefeld University published in 1983"
TL;DR: In this paper, a new vector strategy for the insertion of foreign genes into the genomes of gram negative bacteria not closely related to Escherichia coli was developed, which can utilize any gram negative bacterium as a recipient for conjugative DNA transfer.
Abstract: We have developed a new vector strategy for the insertion of foreign genes into the genomes of gram negative bacteria not closely related to Escherichia coli. The system consists of two components: special E. coli donor strains and derivatives of E. coli vector plasmids. The donor strains (called mobilizing strains) carry the transfer genes of the broad host range IncP–type plasmid RP4 integrated in their chromosomes. They can utilize any gram negative bacterium as a recipient for conjugative DNA transfer. The vector plasmids contain the P–type specific recognition site for mobilization (Mob site) and can be mobilized with high frequency from the donor strains. The mobilizable vectors are derived from the commonly used E. coli vectors pACYC184, pACYC177, and pBR325, and are unable to replicate in strains outside the enteric bacterial group. Therefore, they are widely applicable as transposon carrier replicons for random transposon insertion mutagenesis in any strain into which they can be mobilized but not stably maintained. The vectors are especially useful for site–directed transposon mutagenesis and for site–specific gene transfer in a wide variety of gram negative organisms.
7,278 citations
TL;DR: In this article, the authors used perturbative QCD in combination with the nonrelativistic quarkonium model to obtain a complete and detailed picture of charmonium and bottomonium production.
Abstract: Hadronic collisions are quite efficient in producing new quark flavours due to the large gluon content of ordinary hadrons. In particular, one may expect sizable yields of heavy quark-antiquark bound states with various spin and orbital quantum numbers. Using perturbative QCD in combination with the nonrelativistic quarkonium model we present a fairly complete and detailed picture of charmonium and bottomonium production. We compare our results on inclusiveJ/ψ and γ distributions with high energypp data and make predictions onηc and χ production.
245 citations
TL;DR: In this article, the concept of a limit ESS was introduced for two-person games in normal form, and several theorems on the properties of such games were provided for the analysis of specific games.
230 citations
TL;DR: In this article, the Susskind fermionic action is expressed explicitly in terms of flavour Dirac fields defined on hypercubes in position space, and the decay constant of the pseudo-scalar Goldstone boson associated with spontaneous breakdown of the U(1) A symmetry is derived.
206 citations
TL;DR: Within limits, such selectivity in the choice of a song tutor proved to be independent of the relative frequency of song output by the father or the neighbour, respectively.
151 citations
TL;DR: In this article, the authors give a classification of minimal algebras having a preprojective component in their Auslander-Reiten quiver, based on the notion of tilting modules.
Abstract: Let A be a finite dimensional, basic and connected algebra (associative, with 1) over an algebraically closed field k. Denote by e1,...,en a complete set of primitive orthogonal idempotents in A and by Ai= A/AeiA. A is called a minimal algebra of infinite representation type provided A is itself of infinite representation type,whereas all Ai, 1≤i≤n,are of finite representation type. The main result gives the classification of the minimal algebras having a preprojective component in their Auslander-Reiten quiver. The classification is obtained by realizing that these algebras are essentially given by preprojective tilting modules over tame hereditary algebras.
146 citations
TL;DR: In this paper, the authors study spaces generated by translations of a fixed function over lattice points and provide algebraic and approximation properties for these spaces which show their applicability for finite element analysis.
132 citations
TL;DR: A new bacteriochlorophyll g has been isolated from Heliobacterium chlorum as mentioned in this paper, which is extremely sensitive to oxygen in the presence of light and its visible absorption spectrum is different from those of all other known bacterio chlorophylls, and a proposal for the structure of the new BCHG is given on the basis of absorption, CD, and 1H-NMR spectra of the corresponding bacteriopheophytin g and two main transformation products of Bchl g.
Abstract: A new bacteriochlorophyll g has been isolated from Heliobacterium chlorum. Its visible absorption spectrum is different from those of all other known bacteriochlorophylls, and it is extremely sensitive to oxygen in the presence of light. A proposal for the structure of the new bacteriochlorophyll g is given on the basis of absorption, CD, and 1H-NMR spectra of the corresponding bacteriopheophytin g and two main transformation products of Bchl g.
131 citations
TL;DR: In this paper, a two-photon resonant sum and difference frequency mixing (SDF) was used to generate coherent tunable VUV radiation of narrow spectral width by pulsed dye laser radiation in Hg vapor.
Abstract: Coherent tunable VUV radiation of narrow spectral width is generated by two-photon resonant sum and difference frequency mixing (\omega_{vuv}^{\pm} = 2\omega_{uv} \pm \omega_{D}) of pulsed dye laser radiation in Hg vapor. The UV frequency ω uv is tuned to the two-photon resonances 61S 0 - 71S 0 ( \lambda_{uv} = 3127.6 A), 61S 0 -61D 2 ( \lambda_{uv} = 2802.9 A), and 61S 0 - 71D 2 ( \lambda_{uv} = 2594.5 A). A second dye laser produces tunable radiation at ω D ( \lambda_{D} = 4200-6700 A). At input powers of 1-2 MW, the different conversion schemes generate VUV light pulses of typically 0.5-3 kW in spectral regions between 1090 and 1960 A. The experimental results provide information on the wavelength dependence of the generated VUV output, on the conversion efficiency, the phase-matching conditions, and on conversion limiting saturation phenomena. Besides the resonant frequency conversion, nonresonant frequency tripling and mixing is investigated at \lambda_{vuv} = 1800-1880 A in the vicinity of the resonance transition 61S 0 -61P 1 ( \lambda = 1849.5 A).
112 citations
TL;DR: In this article, the finite temperature deconfinement transition in SU(3) Yang-Mills theory was studied using a high statistics Monte Carlo evaluation on a 83 × 3 lattice, and it was shown that at the critical temperature, there is a clear two-state signal; above and below, we have hysteresis behaviour.
111 citations
TL;DR: In this paper, a complete analysis of the one-loop radiative corrections to the associated production of a Higgs boson and a neutral vector boson in e + e − annihilation up to energies and Higgs-boson masses of 1 TeV was presented.
TL;DR: An inexpensive three-step synthesis for large-scale preparation of 1,2,3,4,5-pentamethylcyclopentadiene is reported in this paper, where an improvement of Burger's route involving 2,3.4,6-tetrahydro-2, 3, 4, 6 -tetramethyl-γ-pyrone and 2,4.5,tetramerethyl-cyclopent-2-enone raised the overall yield to about 34% of the desired compound.
TL;DR: Adult patterns and the development of the nucleus of origin of centrifugal innervation of the retina, the nucleus olfacto-retinalis (NOR), were studied with horseradish peroxidase in 2 cichlid fish species to suggest the only known centrifugally projecting nucleus in vertebrates which lacks extensive degenerating patterns during early development.
TL;DR: In this paper, an efficient two-photon resonant frequency conversion of powerful pulsed dye laser radiation generates in Xe intense VUV light at 2π-6p [ \frac{5}{2},2 ] two-poton resonance (α = 255.9 nm).
Abstract: Efficient two-photon resonant frequency conversion of powerful pulsed dye laser radiation generates in Xe intense VUV light at \omega_{VUV} = 2\omega_{UV} - \omega_{D} . The frequency ω UV is tuned to the 5p-6p [ \frac{5}{2},2 ] two-photon resonance ( \lambda_{UV} = 255.9 nm). For dye laser radiation ω D at \lambda_{D} = 300-760 nm ω VUV is tunable in the spectral range of \lambda_{VUV} = 155-220 nm. The resonantly enhanced conversion efficiency is typically 0.05-0.2 percent; the generated VUV pulse power P_{VUV} = 0.5-1 kW. The experimental results provide detailed information on conversion limiting saturation phenomena and their dependence on the input power and the detuning of ω UV from the two-photon resonance.
TL;DR: In this paper, the authors apply Mandelbrot's concept of fractal dimension D to surfaces and describe how surfaces can provide environments (e.g. for adsorbates) with 2⩽D 2 are "ideally irregular" (self-similar) surfaces; and D→3 obtains in the limit where a surface visits every point of a volume.
TL;DR: Current evidence suggests that the electroreceptive ampullary organs are as phylogenetically old as all other vertebrate sensory systems; they are now known to be relatively common among anamniotic vertebrates.
Abstract: The system of lateral-line organs in urodeles was examined by the use of various lightand electron-microscopical techniques. The results show that, in addition to the well-known mechanoreceptive neu-romast organs, a second type of receptor can be identified. This second type of organ was presumably seen by earlier workers, but they seemingly failed to point out the distinction between the two organs. The presently described organs are anatomically similar to the ampullary organs of various anamniotic species such as Brachiopterygii, sturgeons, lungfish, and silurids. In all these species the ampullary organs display only one afferent fiber but no efferent innervation and are situated around an ampullary enlargement in or below the epidermis as in urodeles. All ampullary receptors including those of urodeles are very sensitive to weak electrical fields. Similar to the situation in teleosts, the ampullae of urodeles show numerous microvilli but no kinocilia. All other nonteleostean ampullary receptors appear to possess only kinocilia as apical specializations but no microvilli. Current evidence suggests that the electroreceptive ampullary organs are as phylogenetically old as all other vertebrate sensory systems; they are now known to be relatively common among anamniotic vertebrates. Since all ampullary receptors share many common characteristics, it is assumed that they were derived from one phylogenetic precursor but have evolved certain peculiarities in each species not shared by other ampullary receptors.
TL;DR: In this article, the latent heat of deconfinement in SU(3) Yang-Mills theory is calculated from the difference in energy density between the deconfined and the confined phases at the critical temperature Tc.
TL;DR: In this article, the production of single mesons and opposite side pairs of mesons in hadron-nucleus and nucleus nucleus collisions is calculated in the framework of the QCD parton model, with the assumption that quarks and gluons undergo multiple scattering in the nucleus.
Abstract: Production of single mesons and opposite side pairs of mesons in hadron-nucleus and nucleusnucleus collisions are calculated in the framework of the QCD parton model, with the assumption that quarks and gluons undergo multiple scattering in the nucleus. A comparison with all available data is made. It is also shown that the anomalous nuclear enhancement, especially its dependence on the flavour, can be quantitatively described within the model. Furthermore, we predict no enhancement for symmetric pairs as it seems to be indicated by the data. Predictions for largep
T production in α−α scattering at ISR are made.
TL;DR: Since thecurrent line can be coded only processing the preceding line and the current line one-directionally and simultaneously, implementation of a coder becomes simple and redundancy can be effectively removed regardless of whether the document is simple or complicated.
Abstract: Hybridization tests were carried out with the allopatric and sympatric haplochromine cichlids Haplochromis burtoni (Lake Tanganyika), H. nubilus (L. Victoria), H. elegans (L. George) and H. "black lividus" (L. Victoria). Female H. nubilus crossed with male H. burtoni produce lethal hybrids which do not survive the larval stage. The reciprocal cross, female H. burtoni x H. nubilus, produces F1, F2, F3 hybrids with a normal sex ratio, and fertile backcrosses F1 x H. burtoni and F1 x H. nubilus with a skewed sex ratio. In behavioral tests female H. nubilus spawn readily with H. burtoni males (lethal cross), whereas female H. burtoni spawn rarely with male H. nubilus (fertile cross). The inheritance of coloration, the "egg-dummies" pattern on the anal fin, and reproductive vigor in the hybrids are analysed in detail. Crosses which involve male H. elegans x female H. nubilus and male H. "black lividus" x female H. nubilus are fertile but have skewed sex ratios in favor of the females. The importance of environmental instability, learning and hybridization in cichlid fish speciation are discussed.
01 Jan 1983
TL;DR: A search through the literature indicates that information on the influence of hormones on early developmental processes is only available from a few avian species, and, in most cases, only one steroid has been looked for.
Abstract: The dependence of behaviour patterns on circulating levels of steroids in adult birds is well established (for a survey see Silver et al. 1979). However, only recently has attention been focussed on hormonal and neuronal development in very young birds during their first few days of live (cf. Adkins 1975, 1978, Hutchison 1978; for survey see Goldman 1978, and Plapinger and McEwen 1978). A search through the literature indicates that information on the influence of hormones on early developmental processes is only available from a few avian species (mainly the Japanese quail and the domestic chick), and, in most cases, only one steroid has been looked for.
TL;DR: In this article, the vibrational spectra of the early transition metals (MoOS 3 2−, WOS3 2−, MoS 4 2− and WS 4 2 − ) are discussed in relation to the molecular structure of the compounds and especially to the wide variety of the coordination types of the thiometalate ligands.
TL;DR: In this paper, a theory of the prominence of numbers of the decimal system is discussed. But it is restricted to the case of the powers of 10 and the scale of a decision problem is chosen according to the rule that it is maximal subject to the condition that the range of reasonable alternatives contains at least three prominent numbers.
Abstract: Publisher Summary This chapter discusses a theory of the prominence of numbers of the decimal system. Basic components of the theory are the limited rational principles of rule construction by iterated addition or subtraction of a given amount and the refinement of a scale by adding the means of any two neighbors and its coarsening by omitting all uneven elements. Applying these principles to the powers of 10, various scales with different degrees of exactness can be constructed. Empirical observations suggest that among different scales with about the same exactness generally the one that can be constructed in an easier way is chosen. Empirical results indicate that the prominence of the set of numbers resulting from a specific decision situation is in many cases about one tenth of the numbers in question. The prominence of a specific decision problem seems to be selected according to the rule that it is maximal subject to the condition that the range of reasonable alternatives contains at least three prominent numbers.
TL;DR: In this article, the isomeric lithium compounds exist in a mobile equilibrium and can be transferred to the benzoxazol-2-yltrimethylsilane (I) by reaction with trimethylchlorosilane.
TL;DR: The control system of the femur-tibia joint of the stick insect shows different properties depending on whether the animal is standing or walking, which indicates that the state of the leg does not seem to be controlled by the neural subsystem of the foot itself but by a more generalized system, which differs in its properties depending upon whether the whole animal isStanding or walking.
Abstract: The control system of the femur-tibia joint of the stick insect ( Carausius tnorosus ) shows different properties depending on whether the animal is standing or walking. The properties of the system were examined when the animal was walking on a treadwheel and when the examined leg rested on a platform fixed beside the wheel. The results show that the properties of the system in the standing leg of a walking animal are similar to those of a walking animal rather than those of the standing animal. This indicates that the state of the leg (standing or walking) does not seem to be controlled by the neural subsystem of the leg itself but by a more generalized system, which differs in its properties depending upon whether the whole animal is standing or walking. Furthermore the results show how the behaviour of the system changes for the two alternative states.
TL;DR: In this article, the in 2-position trimethylstannylated heterocycles are formed in good yields by reaction of the lithiated heterocycle benzothiazole, N -methylbenzimidazole, n -methylimidazoles, N-methyltriazole and thiazole with trimethylchlorostannane.
TL;DR: The attempt to incorporate the phenomenon in the coherent Kok model shows that the Oscillatoria sequence fully resembles those with Chlorella, if the first flash signal and 40-50% of the signal observed under the second flash is simply removed from the sequence.
Abstract: When thylakoid preparations of the filamentous blue-green alga Oscillatoria chalybea are exposed to short (2 or 8 μs) saturating light flashes, the oxygen evolution pattern can be distinguished in several respects from the one usually observed in Chlorella. Thus, it appears that a substantial electrochemical signal is already seen under the first flash with maximal flash yield always occurring under the fourth flash. This refers to dark adapted preparations (up to 60 min). Fitting of such an experimental sequence in the 4-state Kok model yields an S-state population consisting of 36-41% S₀, 40-49% S₁, 1-10% S₂ and up to 13% S₃. No abnormality under the first flash is seen in such preparations. Characteristic for sequences with Oscillatoria preparations is a high level of misses which are in the region of 25 per cent, whereas double hits do not seem to play a substantial role in the damping of such sequences. The existence of metastable S₃, anyway inconsistent with the coherent Kok model, is not confirmed by mass spectrometry. No ¹⁸O₂ seems to be evolved under the first flash from Oscillatoria thylakoids suspended in 50% H₂¹⁸O. although, when judged from the absolute amperometric signal amplitude, mass spectrometric detection of O₂ should have been possible. With the same method we are fully able to detect ¹⁸O₂ under the second flash in Chlorella vulgaris. In Chlorella this is true for experimental conditions in which the amperometric signal amplitude under the second flash is even smaller than those under the first or second flash in Oscillatoria. The attempt to correlate the amperometrie signal observed under the first flash with a photoinhibition of respiration in our prokaryotic organism was not successful. However, the attempt to incorporate the phenomenon in the coherent Kok model shows that the Oscillatoria sequence fully resembles those with Chlorella, if the first flash signal and 40-50% of the signal observed under the second flash is simply removed from the sequence. The remaining sequence exhibits the usual properties known from Chlorella or higher plant chloroplasts. If one assumes contribution of the reduced state S₋₁ to the dark population of S-states, a fit in the five rank Kok model yields correct adjustments with a S-state distribution of 6-20% S₋₁, 31-40% S₀, 49-54% S₁, 0% S₂ and 0% S₃ which would be fully consistent with the Kok model and corresponds to the distribution observed with Chlorella or higher plant chloroplasts. The question what the first electrochemical signal is due to remains unanswered.
TL;DR: In this article, a nonresonant frequency tripling of ultraviolet (UV) radiation (λuv = 216-223 nm, generated by sum frequency mixing of the outputs of a frequency doubled pulsed dye laser and of the Nd-YAG pump laser) generates in neon coherent light in the extreme ultraviolet (XUV).
TL;DR: In Pseudomonas aeruginosa strain PAO the chromosome-mobilizing IncP-1 plasmid R68.45 was unstable whereas the parent plasmID R68 was stable, and deletion derivatives were stable.
TL;DR: For instance, the authors argues that what is fashionable world-wide becomes fashionable in Germany as well, and this densely woven net of interchanges makes it difficult to portray German sociology as such.
Abstract: Germany is not an isolated country, nor is social research in Germany a self-insulating process. Especially after World War II, there has been a strong influx of Western thought, Western methods, Western outlooks. What is fashionable world-wide becomes fashionable in Germany as well. This densely woven net of interchanges makes it difficult to portray German sociology as such. An attempt to do so would result in an artificial
01 Aug 1983
TL;DR: In this article, the cross-molecular-beam method has been used to measure relative integral cross sections σ r (υ = 1, j ; E ) of the endothermic (0.75 eV) reaction K + HF(υ, j ) → KF + H as a function of both the rotational quantum number j ( j = 5, 6 and 7) and the translational energy E ( 0.55 ⊽ E ⩽ 1.32 eV), which is about a factor of 200 more efficient in promoting
Abstract: The crossed-molecular-beam method has been used to measure relative integral cross sections σ r (υ = 1, j ; E ) of the endothermic (0.75 eV) reaction K + HF (υ = 1, j ) → KF + H as a function of both the rotational quantum number j ( j = 5, 6 and 7) and the translational energy E (0.55 ⩽ E ⩽ 1.32 eV) of the reagents. The vibrational-rotational (υ, j ) states of HF were populated by infrared pumping with the radiation of a properly tuned pulsed chemical HF laser. In addition, relative cross sections with υ = 0 but averaged with respect to the initial rotational-state distribution of the HF molecules were also determined. The results exhibit three remarkable features: (a) σ r (υ = 1, j ; E ) rises with increasing j , (b) the steepness of the ascent roughly decreases with increasing E , (c) at E = 0.98 eV reagent vibrational energy is about a factor of 200 more efficient in promoting the reaction than reagent translational energy. An intuitive dynamical model suggests that observations (a) and (b) are to be expected for a reaction governed by a potential-energy surface with a late barrier. This is consistent with the well-known interpretation of large vibrational effects as indicated by result (c).