bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructural characterization of stable L‐form cells from Erysipelothrix rhusiopathiae and of accompanying artifacts
Authors: Gumpert J. , Todorov T. , Toshkov As.
Published: July 2010

The stable L‐form of Erysipelothrix rhusiopathiae is a typical protoplast type L‐form. Cells are surrounded by a trilamellar cytoplasmic membrane only. They grow in form of aggregations in liquid media and their diameters vary between 0.1 and 2 μm. Always a large portion of cells undergoes lysis. It seems to be characteristic for L‐form cultures of E. rhusiopathiae that always many artifact structures are formed. The artifacts are spherical particles with diameters of 0.1 μm to more than 3 μm. They can be differentiated from L‐form cells only by electron microscopy. The artifacts consist of electron dense amorphous material and their surface is irregular without a clear boundary line. Obviously, these artifacts are produced from protein components of the medium and from cytoplasmatic components of the lysing L‐form cells.
Elektronenoptische Untersuchungen zur Wirkung von 1‐[p‐(Methylnitrosamino)‐benzylidenamino]‐adamantan auf das Fowl‐Plague‐Virus (FPV) in Zellkultur
Authors: Zöpel P. , Tonew E. , Ulbericht H.
Published: July 2010

The adamantanamine derivative 1‐[p‐(methylnitrosamino)‐benzylidenamino]‐adamantane (MBAA) at a concentration of 40 μg/ml demonstrated no effect on adsorption of fowl plague virus (FPV) on chick embryonal cells. The penetration of the virions took place by means of pinocytosis. In the final stages of penetration the virions became gradually disintegrated. Under the influence of MBAA, after break‐down of the membrane of pinocytic vesicles a swollen part of the virus core remained in cytoplasm. The morphologically visible replication stages were completely blocked by MBAA. From these results it was concluded that the antiviral action of MBAA most probably depends on a block of virus replication between the final stages of the penetration process and the beginning of production of virus specific structural antigens.
Roll der Formiat‐Dehydrogenase in „Serinweg‐Bakterien”︁
Authors: Babel W. , Mothes Gisela
Published: July 2010

Die Formiat‐Dehydrogenase (E. C. 1.2.1.2.) kommt in allen — bisher untersuchten — „Serinweg‐Bakterien”︁ vor, und sie wird induziert durch Methanol und durch Formiat auch bei Bakterienstämmen mit konstitutiver Methanol‐Dehydrogenase, obwohl der von der Formiat‐Dehydrogenase katalysierte Schritt außerhalb des Assimilationszyklus liegt.

Die Formiat‐Dehydrogenase ist bei hinreichend hoher Carbonatkonzentration im Wachstums‐medium für biosynthetische Reaktionen ohne Bedeutung. Sie ist für den Energiehaushalt dieser Bakterien wesentlich. Darauf weist hin, daß die energetisch negative Bilanz des Assimilationszyklus durch Einbeziehung der Formiat‐Dehydrogenase‐Reaktion positiver wird. Gegenüber ATP ist die Formiat‐Dehydrogenase — aus Pseudomonas methylica — unempfindlich. Da dieses Enzym mit der induktiven biosynthetischen Formyltetrahydrofolat‐Synthetase (E.C. 6.3.4.3.) um Formiat konkurriert und letzteres Enzym ATP als Substrat hat, kann ATP trotzdem das Gleichgewicht von Assimilation und Dissimilation allein via Massenwirkungsgesetz wirksam kontrollieren. Bei niedriger ATP‐Konzentration ist die bioenergetische Formiat‐Dehydrogenase begünstigt und bei hoher wird Formiat bevorzugt assimiliert. Aber wesentlicher für die Lage des Gleichgewichts scheint das NAD+/NADH‐Verhältnis, genauer gesagt, die NADH‐Konzentration zu sein, denn NADH hemmt die Formiat‐Dehydrogenase kompetitiv gegenüber NAD+ und nicht‐kompetitiv gegenüber Formiat.

NADH spielt also im methylotrophen Stoffwechsel nicht nur die für andere Ernährungstypen (z. B. aerobe chemoorganoheterotrophe Ernährung) übliche Rolle, sondern es ist außerdem Substrat für biosynthetische Reaktionen und zentrale Regelgröße.
Steroidtransformation mit immobilisierten Mikroorganismen. III. Abbau der Seitenkette von Cholesterolderivaten mit immobilisierten Zellen von Mycobacterium phlei und M. smegmatis
Authors: Atrat P. , Hörhold C. , Buchar M. J. , Koschtschejenko K. A.
Published: July 2010

The cholesterol derivatives 3,3‐ethylenedioxycholest‐5‐en I and 4‐cholesten‐3‐(0‐carboxymethyl)oxime II were transformed into the coresponding androstenedione derivatives by selective cleavage of the sterol side chain with immobilized preparations of Mycobacterium phlei IMET SG 1026 and M. smegmatis IMET H 124. The influence of three immobilization methods on fermentation activity and stability was investigated. The immobilized cells of M. phlei IMET SG 1026 were found to be suitable to transform the structure modified sterol II in a periodic process over a long period into the androstenedione in a yield of 50–70%. Immobilized cells of M. phlei have a higher transformation stability in comparison with free intact cells.
In vivo and in vitro recombination of Lambda DNA in CaCl2 transfection
Authors: Betcke A. , Pfeifer M. , Pöhlmann Ch. , Kurth M. , Hartmann M. , Liebscher D.‐H.
Published: July 2010

Using CaCl2 mediated transfection with Lambda DNA fragments, in vitro joining by ligase and in vivo recombination with helper phage DNA are effective systems for generating artificial recombinants. Recombination effiicencies are 20–30% in the in vitro and in vivo recombination systems.

At 30 to 37 °C T4 ligase mainly joins natural cohesive λ ends, while at 12 °C the EcoRI‐generated termini are preferentially ligated to form biologically active molecules, if the cloning vector λ 401 is used, which has only one EcoRI target. The ligation products were characterized by gel electrophoresis and CaCl2 transfection.

For in vivo recombination a new CaCl2 transfection system was developed, termed postinfectiondependent CaCl2 transfection system, which is based on the infection of recipient cells with helper phages after transfection. In marker rescue experiments using this method not only single but also double recombination occurred between two independent Δ DNA fragments and the helper phage DNA.
Effect of five pesticides on the mycelial growth of some soil and pathogenic fungi
Authors: El‐Hissy F. T. , Abdel‐Kader M. I. A.
Published: July 2010

The effect of three doses (the lowest is the recommended dose in the field) of 5 pesticides namely: Ceresan, Orthocid (fungicides), VCS‐438 (herbicide), and Dursban and Dipterex (insecticides) on the mycelial dry weight of Aspergillus fumigatus, Fusarium moniliforme, Penicillium italicum, and Sclerotium cepivorum was tested 2, 4, 6, 8 and 10 days after treatment. All the pesticides induced inhibition of mycelial growth of the test fungi. Only VCS‐438 at the low dose was stimulatory to F. moniliforme after 4 and 6 days and to P. italicum after 4 days. The rate of inhibition was influenced by the type of fungus, the age of the mycelium, and the dose of the pesticide. At the end of the experiment the two fungicides were detoxified by the test fungi with a rate higher than that of the other pesticides.
Factors which influence CaCl2 dependent transfection of Lambda DNA in Escherichia coli K12 recipients
Authors: Pfeifer M. , Pöhlmann Ch. , Betcke A. , Kurth M. , Liebscher D.‐H.
Published: July 2010

This paper presents further parameters influencing the competence, the process of DNA uptake and the efficiency of plating of CaCl2‐treated E. coli K12 strains. We have found that the process of DNA uptake depends not only on the treatment of bacteria with a certain CaCl2‐concentration but is also influenced considerably by a shift‐down of the CaCl2‐concentration in the reaction mixture. The pH of the growth media and of the reaction mixture plays an important role in maintaining of optimal transfection. The efficiency of plating is influenced by the thickness of the top layer and the concentration of bacteria on the plate.

Without genetic variation of the strains, by only varying the mentioned factors we could improve the efficiency of CaCl2 transfection at about two orders of magnitude to a maximum of 6 × 105 pfu/μ DNA.
Wirkung von Ölen und Fettsäuren auf Wachstum und Enzymbildung bei Thermoactinomyces vulgaris II. Methodik der Wachtumsmessung in einer Submerskultur in Gegenwart von Öl
Authors: Leuchtenberger A. , Schaffner B. , Ruttloff H.
Published: July 2010

Zur Wachstumsmessung einer Kultur des Proteasebildners Thermoactinomyces vulgaris in einem löslichen Nährmedium werden drei Methoden (Bestimmung des Proteingehaltes im Sediment, der Trockensubstanz sowie der Extinktion) hinsichtlich ihrer Reproduzierbarkeit getestet. Dabei wird insbesondere der Einfluß von Rapsölzusätzen – die sich zur Schaumbekämpfung erforderlich machen – auf das Meßergebnis untersucht. Nach den gewonnenen Befunden sind in den Ansätzen ohne Öl alle 3 Methoden, mit Rapsöl hingegen nur die Protein‐ und die Trockensubstanzbestimmung geeignet. Die Streubreite der Ergebnisse ist bei den geprüften Methoden unterschiedlich. Der wachstumsfördernde Einfluß von 0,1% Rapsöl kann in jedem Falle nachgewiesen werden.
Einfluß von Amitrol auf Claviceps fusiformis, Stamm SD 58
Authors: Schmauder H.‐P. , Mater W. , Gröger D.
Published: July 2010

The influence of amitrole (3‐amino‐1.2,4‐triazole) on growth, alkaloid formation and on some aromatic as well as ergoline pathway specific enzymes were studied in Claviceps strain, SD 58. In a phosphate‐rich medium the addition of amitrole can partially reverse the alkaloid‐depressing effect of phosphate. Using a typical fermentation medium amitrole reduces the activities of ergoline specific enzymes but increases drastically tryptophan synthase activity and to a lesser extent transaminases of aromatic amino acids.
Allgemeine Regulation der Aminosäurebiosynthese in Hansenula henricii
Authors: Bode R. , Birnbaum D.
Published: July 2010

The general control of amino acid biosynthesis was investigated in Hansenula henricii. By limitation for single amino acids in wild type strain and mutants no derepression of enzymes was caused. In prototrophic revertants however, obtained from auxotrophic mutants (his, pdx) enzyme activities were 2 – 17 times higher than in the wild type. In these revertants enzymes of the biosynthetic pathways for tryptophan, phenylalanine, tyrosine, arginine, histidine, cysteine, methionine, asparagine, threonine, and isoleucine were derepressed. The amino acid pool pattern of the revertants is completely different from that in the wild type strain. A discussion of possible mechanisms of general control of amino acid biosynthesis in H. henricii is presented.
A mutant of Salmonella typhimurium with an abnormal septation pattern associated with an inhibition of RNA synthesis
Authors: Herrero E. , Guerrero R. , Wolf‐Watz H. , Normark S.
Published: July 2010

A mutant strain of S. typhimurium that is disturbed in the regulation of cell division and macromolecular synthesis is described. The life cycle of the mutant can be divided into two discrete stages. When growing in rich medium at a low cell density, cell division is inhibited and the cells filament at the same time as the relative amount of RNA shows a continuous increase. However, at a certain stage, RNA synthesis stops and the filaments start to septate resulting in chain‐formation. These chains can thereafter segregate into individal cells of unit cell length. The accumulation of RNA is rather due to a regulatory defect in the synthesis of the stable RNA species than to an unusual stability of messenger RNA (mRNA)as the half life of mRNA was estimated to 2.3 minutes during the period of RNA accumulation. Latter inhibition of RNA synthesis affects only stable species of RNA. The ppGpp pools of the strain did not fluctuate during growth, showing that inhibition of RNA synthesis is not correlated to changes in the level of ppGpp. Different treatments that reduce the level of transcription such as sublethal concentrations of rifampicin, a shift‐down or high concentrations of nalidixic acid, all induced cell division of filamentous cells, suggesting that there exists an intimate relationship between macromolecular synthesis and cell division. The behaviour of this mutant fits best with the proposed hypothesis that the biomass to volume ratio is of importance in the regulation of cell division in bacteria.
Torulopsis ethanolitolerans n. sp. and T. ethanolitolerans var. minor n. var.
Authors: Rybářová Johanna , Štros F. , Kocková‐Kratochvílová Anna
Published: July 2010

A new yeasts. Torulopsis ethanolitolerans and its variety minor, both isolated from industrial sulphite fodder yeast cultivated on synthetic ethanol as the only source of carbon, originally designated R 5. R 6 and the variety R 7, are described. This species differs from all recently accepted Torulopsis species (resp., Candida species), which do not assimilate nitrate, not ferment any sugars, not produce urease, by the assimilation of maltose, but not of sucrose, lactose and D‐xylose.
Laugung von uranhaltigen Phosphoriten mit heterotrophen Mikroorganismen
Authors: Kullmann K.‐H. , Schwartz W.
Published: July 2010

The problem of heterotrophic leaching of metals was tested with uranium‐containing phosphorites under laboratory conditions with regard to possible technical applications. As leaching agents we used the acids of citric and lactic acid fermentation, carried out with a strain of Aspergillus niger in sulfite liquor under different conditions and with lactic acid bacteria in wheye. Up to 12% uranium were soluted with citric acid fermentation of Marocco phosphorite containing 153 ppm U in Aspergillus niger cultures within 27 days.
Effects of methionine sulphoximine on protein transients during heterocyst differentiation in Anabaena and Cylindrospermum spp.
Authors: Grover I. S. , Puri S.
Published: July 2010

Heterocystous blue‐green algae normally do not develop heterocysts if grown in the medium enriched with ammonium compounds. If such cultures are resuspended in a medium lacking combined nitrogen, the heterocysts differentiate within 24 h. L‐methionine‐DL‐sulphoximine (MSO) has been reported to induce heterocysts even in the presence of ammonium chloride. The changes in gel electrophoresis protein profiles of cultures developing heterocysts, in the ammonium chloride enriched medium supplemented with MSO suggest that heterocyst differentiation in the presence of ammonium chloride and MSO may be due to derepression of heterocyst formation genes by MSO.
Regulation by repression of urease biosynthesis in Proteus rettgeri
Authors: Zorn C. , Dietrich R. , Kaltwasser H.
Published: July 2010

Measuring the specific enzyme activity in cells of Proteus rettgeri it was shown that urease formation is controlled by repression through ammonia. Derepressed synthesis of the enzyme, as initiated by the absence of ammonia, required an external nitrogen source, which may not only be urea, but also nitrate, glutamate or nutrient broth. In contradiction to earlier reports the observations indicated that urea is not required for the synthesis of this enzyme, and that, therefore, urease is not an inducible enzyme in this microorganism.
AS‐IL—ein neuer, in der DDR aufgefundener Stamm des Cyanophagen AS‐I
Authors: Gorjušin V. A. , Stenz E. , Averkiev A. A.
Published: July 2010

In samples, taken from waters in the surroundings of Leipzig (GDR) in 1978, we found cyanophages in Central Europe for the first time. Among other cyanophages we isolated the new strain AS‐IL. Out of 20 tested cultures of unicellular cyanobacteria seven strains belonging to the genus Synechococcus proved to be susceptible for this cyanophage. In morphology AS‐IL corresponds to the cyanophage AS‐I found in the U.S.A., to which it is related serologically, too. AS‐IL differs from the other strains of AS‐I by a shorter growth cycle, especially a shorter latent period, by the kinetics of inactivation by antiserum, and by a somewhat narrower pH scope of stability. Consequently the isolated cyanophage is to be looked at as a new strain of the cyanophage AS‐I.
Regulation of bistability in glucose metabolism of Escherichia coli ML 30 chemostat cultures by cyclic AMP
Authors: Müller P. J. , Römer W.
Published: July 2010

Evidence is presented that cyclic AMP is engaged in the regulation of a bistability in the glucose and energy metabolism of NH3‐limited chemostat cultures of Escherichia coli ML 30. Cyclic AMP probably reverses the repression of the citric acid cycle by glucose favouring the state of glycogen and energy overproduction.
Aspects of biotechnology in steriod biotransformation
Authors: Malik V. S.
Published: July 2010

Due to the increasing world population, supply of steroids is dwindling. New sources of steroids is dwindling. New Sources of steroids may be found and the existing steroids and sterols may be better utilized. The role of biotechnology in the production and efficient utilization of steroids and sterols is discussed.
Analysis of genetic markers in new breeding stocks of the yeast Saccharomycopsis lipolytica
Authors: Kurischko Cornelia
Published: July 2010

For development of breeding stocks of S. lipolytica for genetic investigations we isolated and identified several auxotrophic mutants. After selection of strains with normal meiotic segregation pattern for the markers metA, lysA, argA, leuA, uraA, hisA it was shown that the loci metA and lysA and the loci argA and leuA are linked, crossing over frequencies are 25 ± 0.9% and 30 ± 1.2%, respectively.

We identified several complementation groups. The marker uraA is allel to ura3 from strains of the Donner Laboratory (USA).

These results are the basis for selection of special mutants for forthcoming investigations.

The existence of linkage fragments makes it possible to use these strains as tester strains for genetic analysis.
Complex principal component analysis of sea‐level pressure over the eastern USA
Authors: Davis Jerry M. , Estis Frank L. , Bloomfield Peter , Monahan John F.
Published: July 2010

The purpose of this study is to identify preferred areas of synoptic‐scale disturbance activity through the use of the objective analysis technique called complex principal component analysis. This technique is applied to a sea‐level pressure data set consisting of twice daily observations (00 and 12 GMT) for the months January through to March for the years 1973–1976 and 1979–1982. These months were chosen to encompass the time frame of the Genesis of Atlantic Lows Experiment (GALE) 1986. The geographical area studied extended from approximately 30°W to 120°W and 25°N to 60°N.

The complex principal component analysis technique allows the detection of propagating features in the pressure data set. The eigenvalues, complex eigenvectors (components), and complex component scores are extracted from an augmented data matrix and are used to compute four measures that define the propagating features within the data set.

Research has indicated a spatial relationship between cyclone and anticyclone tracks and the variance in station or sea‐level pressure, especially when the pressure data have been filtered to examine a frequency window traditionally associated with synoptic‐scale activity. The 2–10‐day period was selected for examination of synoptic‐scale activity in this study.

The results of the analysis produced four components that could be given a preliminary, physical interpretation. The variability pattern produced by component 1 accounts for the movement of cyclones/anticyclones guided by the mean mid‐tropospheric flow. Component 2 represents the cold air outbreak anticyclones that move south‐eastward into the eastern USA. Component 3 is linked to the cold air outbreaks over the western USA and to cyclone movement in the eastern USA and Canada. Component 4 represents cyclones that move out of the central and southern states to become east coast systems. The results are not without ambiguities, which are discussed.
Interrelationships between Indian and northern Australian summer monsoon rainfall values
Authors: Gregory S.
Published: July 2010

Relationships between both the Indian summer monsoon rainfall and the northern Australian summer monsoon rainfall and the Southern Oscillation have been studied previously, and Indian conditions related to Darwin pressure trends, but relationships between the rainfall conditions of the two areas have not been studied. This was effected in terms of generalized regional rainfall values for June‐September for 10 Indian regions and December‐March for four Australian regions. Preceding Australian conditions had virtually no significant correlation with succeeding Indian conditions, but these Indian conditions did show significant correlations with many succeeding Australian regional values. These were examined in terms of simple correlation, quintile tabulation, and multiple correlation and regression, and the more significant relationships were extended further by considering generalized sea‐surface temperature conditions as well. Resultant relationships were evaluated in terms of the 10 years that follow the period of analysis.
A method of agrotopoclimatic division and its practice in China
Authors: Qiyao Lu , Jingming Yu , Baopu Fu
Published: July 2010

The principles, methods, indices, and classification system of agrotopoclimatic division are discussed, as practised for the Shaxi River Basin (SRB) of Fujian Province in China. This paper introduces methods proposed by the authors to calculate the spatial distribution of agroclimatic resources (temperature, humidity, precipitation, and wind speed) in a mountainous area, which may effectively disclose the macro‐ and micro‐variations of the spatial distribution of topoclimate, thereby creating the prerequisites for agrotopoclimatic divisions.
Class—A Canadian land surface scheme for GCMS. I. Soil model
Authors: Verseghy Diana L.
Published: July 2010

A new GCM land surface scheme is introduced, incorporating three soil layers with physically based calculations of heat and moisture transfers at the surface and across the layer boundaries. Snow‐covered and snow‐free areas are treated separately. The energy balance equation is solved iteratively for the surface temperature; the surface infiltration rate is calculated using a simplified theoretical analysis allowing for surface ponding. Snow cover is modelled as a discrete ‘soil’ layer.

The results generated by CLASS are compared with those of an older model incorporating the force‐restore method for the calculation of surface temperature and a bucket‐type formulation for the ground moisture. Several month‐long test runs are carried out in stand‐alone mode. It is shown that the surface temperature in the old scheme responds more slowly to diurnal forcing and more quickly to longer term forcing than that modelled by CLASS, while its one‐layer representation of soil moisture proves incapable of reproducing changes in the surface fluxes owing to surface variations of moisture content. Finally, the lumped treatment of snow and soil in the old scheme results in an extremely fast disappearance of the snow pack under certain conditions.
Indian summer monsoon rainfall and 200‐mbar meridional wind index: Application for long‐range prediction
Authors: Parthasarathy B. , Kumar K. Rupa , Deshpande V. R.
Published: July 2010

Verma and Kamte (1980) and Joseph et al. (1981) identified the association between Indian monsoon rainfall and 200‐mbar meridional wind index for the month of May, and indicated its potential for prediction of the seasonal rainfall.

A detailed investigation has been made of this relationship between the monsoon rainfall over India and the meridional wind index (arithmetic average of 200‐mbar meridional wind component for May at Bombay, Delhi, Madras, Nagpur, and Srinagar) based on the data for the period 1964–1988.

The relationship between all‐India monsoon (June‐September) rainfall (R) and the wind index (Vm) is negative (correlation coefficient = −0.72) and is significant at the 0.1 per cent level and the regression equation based on this data, for the period 1964–1988, is R = 86.98–2.44 Vm. The stability and consistency of the relationship between rainfall and the wind index have been examined over sliding widths of 15 and 21 years, and the relationship is found to be significant at the 1 per cent level for all windows of 21‐year widths. The meridional wind index shows a good potential in the long‐range prediction scheme of the Indian monsoon rainfall, along with other parameters.
Climatological patterns of thunderstorm activity in south‐eastern USA
Authors: Easterling David R.
Published: July 2010

Climatological patterns of summertime thunderstorm activity are examined for most of southeastern USA, excluding the Florida peninsula. Monthly numbers of thunderstorm observations at 61 stations for the period 1951–1977 are analysed by means of principal components analysis (PCA) to identify recurring spatial patterns. The first seven components are found to contain non‐random patterns and are subjected to an oblique rotation. The results indicate that there are approximately six distinct spatial patterns. A high correlation between two of the rotated components and the similarity of their spatial loading patterns implies that they may be manifestations of the same pattern. Months with the highest component scores for each of the first four components are presented as pattern examples, and their upper level circulation patterns are discussed.
Climatic change and future agroclimatic potential in Europe
Authors: Carter T. R. , Parry M. L. , Porter J. H.
Published: July 2010

In this paper, initial results are reported of a study to evaluate the broad‐scale sensitivity of agriculture to climatic change in Europe. The study employs an agroclimatic index, effective temperature sum (ETS), to relate temperature patterns to the cultivable limits of grain maize (Zea mays). A computer mapping system for the European region is adopted to map ETS on the basis both of present‐day and of possible future mean temperatures. In this way, changes in climate can be depicted as geographical shifts of the limit of potential grain maize cultivation.

The results indicate that a mean annual temperature increase of only 1°C (within the present‐day range of interannual variability) would open up large areas in southern England, the Low Countries, eastern Denmark, northern Germany and northern Poland to potential maize cultivation. An increase of 4°C would move the limit into central Fennoscandia and northern Russia. These represent rates of northward shift of approximately 200–350 km °C−1 in western Europe and 250–400 km °C−1 in eastern Europe. Comparison of these shifts with those estimated on the basis of general circulation model (GCM) projections of future temperatures suggests that a 1°C warming will be achieved well before the time the global climate responds fully to an equivalent doubling of atmospheric carbon dioxide, possibly as early as 2010. Shifts comparable with those for a 4°C warming are achieved under all the GCM scenarios of doubled CO2, occurring perhaps as soon as 2050 if the current growth in emission rates of greenhouse gases were to continue unabated. The rate of shift of the grain maize limit implied for this (high) emissions scenario is in the order of 150–200 km per decade over the next 70 years, slower than this during the next few decades, but faster thereafter.

Such shifts would offer new opportunities for farmers in different regions of northern Europe. However, given the possible rapidity of the shifts, in order for these opportunities to be exploited successfully immediate attention should be directed towards more detailed assessments of crop potential in regions identified as currently marginal for grain maize.
Distribution and intensity of frontal rainfall over greece
Authors: Flocas A. A. , Giles B. D.
Published: July 2010

The amounts and intensities of rainfall are related to each front that crossed Greece during the period 1971–1981 by using synoptic messages from 26 meteorological stations and from 26 autographic rain‐gauges. The fronts were related to five depression tracks described by Flocas. The amount of rainfall was considered for periods of 15, 30, and 60 minutes and related to slight, moderate, heavy, and violent intensities. This information will provide a climatological background to forecasts of frontal rainfall.
Derivation of ocean—Atmosphere heat fluxes in a tropical environment using satellite and surface data
Authors: Michael K. J. , Nunez M.
Published: July 2010

Ocean—atmosphere heat fluxes measured at John Brewer Reef (80 km north‐north‐east of Townsville, Australia) were compared with regional heat fluxes estimated from non‐direct surface data and information from a number of satellite sensors. Data from the visible channel of the Japanese Geostationary Meteorological Satellite (CMS) were collected for the location, as well as daily atmospheric soundings from NOAA‐9. Sea‐surface temperatures were obtained from a blend of ship observations and NOAA‐9 data. A relationship was developed that estimated solar radiation from GMS visible reflectance data. Incoming longwave radiation was estimated with the LOWTRAN 6 radiative transfer model applied to profiles of temperature and humidity derived from NOAA‐9 soundings. The bulk aerodynamic formulation was used to form regional estimates of the turbulent heat fluxes, combining wind speed from the Darwin Tropical Wind Analysis, blended sea‐surface temperatures, and near‐surface specific humidity related to satellite‐derived precipitable water vapour. A variety of approaches for estimating the near‐surface specific humidity were examined. The root mean square differences (measured—estimated) between the weekly averaged values of the net solar radiation flux, the net longwave radiation flux, the total turbulent heat flux, and the total ocean—atmosphere heat flux were estimated as 12, 10, 45 and 50 Wm−2 respectively. Time series of the weekly heat fluxes are presented for the period June 1985 to April 1986.
A surface energy exchange model of glacier melt and net mass balance
Authors: Munro D. Scott
Published: July 2010

An energy balance model of surface climate and melt for a glacierized area is described, and applied to simulate ablation and net mass balance on Peyto Glacier. Surface characteristics are assigned according to general knowledge from physical climatology and experimental data from the glacier itself. A known elevational distribution of snow covers the glacier at the beginning of the ablation season, then melts in response to simulated energy input to the surface, thus exposing an ever increasing area of ice. The end result is the annual net mass balance, which is shown to be very sensitive to annual mean temperature, solar energy input, atmospheric emissivity, surface albedo, and climatic regime. Maritime climates produce steeper elevational gradients of net mass balance than do continental climates, which, in turn, are steeper than those created under Arctic conditions. It is also found that, in addition to lag caused by internal drainage development, there must be delay in peak meltwater production owing to changing surface conditions because, as snowline elevation rises, the glacier evolves into a more effective collector of solar energy.
Some aspects of the basic characteristics of the Siberian anticyclone
Authors: Sahsamanoglou H. S. , Makrogiannis T. J. , Kallimopoulos P. P.
Published: July 2010

The presence of the Siberian Anticyclone is continuous from October until March in an area defined by longitude 90°‐110°E and latitude 40°‐55°N. From the point of view of central pressure, this anticyclone is much more intense than the permanent anticyclones in the Atlantic and Pacific Oceans. During the last 116 years there have been periods during which the anticyclone appeared stronger and periods when it appeared weaker. Since 1970 a continuous decrease in central pressure of the anticyclone is observed, and is related to a continuous temperature rise of the 1000–500 hPa layer for the same time interval. Their correlation is found to be negative. After 1950, maximum values of central pressure are observed corresponding to maximum values of solar activity. In some of the time series of the anticyclone central pressure, periodicities of 58, 4.5, 3.5, and 3 years are observed, as well as the Quasi‐biennial Oscillation.
Interaction between beet vinasse and iron fertilisers in the prevention of iron deficiency in lupins
Authors: de Santiago Ana , Delgado Antonio
Published: July 2010

BACKGROUND: Recycling of organic byproducts for use as soil amendments or fertilisers may enhance the productivity of soils. The aim of this study was to investigate the potential of sugar beet vinasse to correct iron chlorosis in crops when applied in conjunction with Fe fertilisers such as vivianite and ferrous sulfate (FS). An experiment involving two factors (Fe source and dialysed sugar beet vinasse (DBV) rate) was performed using white lupin (Lupinus albus L.) and calcareous sand as growing medium.

RESULTS: Although vivianite provided lower chlorophyll contents than Fe‐chelate, dry matter production was not significantly different between the two Fe sources. Vivianite was more effective than FS in preventing iron chlorosis in white lupin, but not when DBV was applied. DBV significantly increased chlorophyll content in plants treated with FS after 3 weeks of growth.

CONCLUSION: DBV increased the effect of FS in preventing iron deficiency chlorosis in white lupin. This was due, at least in part, to the inhibition of the precipitation of Fe oxides by organic compounds and to the increase in the content of Fe complexed by organic compounds in the growing medium, as revealed by sequential Fe fractionation. Copyright © 2010 Society of Chemical Industry
Pedicled facial buccinator (FAB) flap: A new flap for reconstruction of skull base defects
Authors: Rivera‐Serrano Carlos M. , Oliver Christopher L. , Sok John , Prevedello Daniel M. , Gardner Paul , Snyderman Carl H. , Kassam Amin B. , Carrau Ricardo L.
Published: July 2010

Background:

The expansion of endoscopic endonasal skull base surgery has resulted in an increased demand for reconstructive options. Reconstruction with vascularized tissue has proven indispensable for reliably separating the cranial contents from the paranasal sinuses following extended endoscopic endonasal approaches (EEA). The introduction of the Hadad‐Bassagasteguy flap (vascular pedicle nasoseptal flap, HBF) at our institution decreased our postoperative cerebral spinal fluid (CSF) leak rates from more than 20% to less than 5%. The HBF is not always available, as the nasoseptal area or its vascular supply can be compromised by tumor or prior surgery. In an attempt to keep pace with rapidly expanding reconstructive requirements, we present the anatomic and cadaveric foundations for novel modifications of the facial artery musculo (‐mucosal) (FAM[M]) and buccinator flaps to allow vascularized reconstruction of the skull base.

Study Design:

Feasibility. Cadaveric study.

Methods:

Using cadaver dissections and measurements, we investigated the feasibility of transposing pedicled buccinator myo/myomucosal flaps into the nasal cavity and skull base. Both muscular and myomuscular flaps were raised, and techniques for transposition into the nasal cavity were investigated. Three fresh and six preserved human specimens were dissected.

Results:

Pedicled facial buccinator flaps with and without mucosa were transposed into the nasal cavity using a variety of maxillary osteotomies. No facial incisions were required. It was demonstrated that the flaps reach the anterior skull base and planum sphenoidale.

Conclusions:

The transposition of pedicled buccinator muscle flaps with and without mucosa into the nasal cavity could reach the anterior skull base and planum sphenoidale, if the appropriate surgical technique is used. The pedicled Facial Buccinator Flap holds significant potential as a reconstructive alternative for a variety of skull base defects, alone or in combination with existing reconstructive options. Laryngoscope, 2010
Automated high‐level disinfection of nonchanneled flexible endoscopes: Duty cycles and endoscope repair
Authors: Statham Melissa McCarty , Willging J. Paul
Published: July 2010

Purpose:

Guidelines issued by the Association of Operating Room Nurses and the Association of Professionals in Infection Control and Epidemiology recommend high‐level disinfection (HLD) for semicritical instruments, such as flexible endoscopes. We aim to examine the durability of endoscopes to continued use and automated HLD. We report the number of duty cycles a flexible endoscope can withstand before repairs should be anticipated.

Methods:

Retrospective review.

Results:

A total of 4,336 endoscopic exams and subsequent disinfection cycles were performed with 60 flexible endoscopes in an outpatient tertiary pediatric otolaryngology practice from 2005 to 2009. All endoscopes were systemically cleaned with mechanical cleansing followed by leak testing, enzymatic cleaning, and exposure to Orthophthaldehyde (0.55%) for 5 minutes at a temperature of at least 25°C, followed by rinsing for 3 minutes. A total of 77 repairs were performed, 48 major (average cost $3,815.97), and 29 minor (average cost $326.85). On average, the 2.2‐mm flexible endoscopes were utilized for 61.9 examinations before major repair was needed, whereas the 3.6 mm endoscopes were utilized for 154.5 exams before needing minor repairs. No major repairs have been needed to date on the 3.6‐mm endoscopes.

Conclusions:

Automated endoscope reprocessor use for HLD is an effective means to disinfect and process flexible endoscopes. This minimizes variability in the processing of the endoscopes and maximizes the rate of successful HLD. Even when utilizing standardized, automated HLD and limiting the number of personnel processing the endoscopes, smaller fiberoptic endoscopes demonstrate a shortened time interval between repairs than that seen with the larger endoscopes. Laryngoscope, 2010
Enhancement of ischemic wound healing by inducement of local angiogenesis
Authors: Milch Hannah S. , Schubert Shai Y. , Hammond Stephen , Spiegel Jeffrey H.
Published: July 2010

Objective:

To determine if monocytes activated toward an angiogenic phenotype can be used to improve ischemic tissue healing in a rat skin flap model.

Study Design:

Prospective experimental study on Wistar rats.

Methods:

A caudally based 9 × 3 cm dorsal skin/panniculus carnosus flap was raised in 15 rats. The animals were divided into three groups: the monocyte group (N = 5) received subcutaneous topical application of 0.1–0.2 cc of i‐Monogrid™, a collagen gel containing M2 angiogenic monocytes; control group 1 (N = 5) received application of cell‐free collagen; and control group 2 (N = 5) received no treatment. Skin flaps were stapled in place and observed for wound ischemia and necrosis of the skin flap. One week postoperatively, skin and underlying muscle were harvested for histologic analyses.

Results:

No macroscopic differences in wound healing or microscopic differences in skin viability were observed. However, the monocyte group showed significantly greater vascular improvement than C1 (P = .047, χ = 3.96), and a trend toward greater vascular improvement than C2 (P = .103, χ = 2.67).

Conclusions:

Delivery of activated pro‐angiogenic monocytes to an ischemic skin flap tended to improve histologic evidence of vascularity without corresponding microscopic or gross evidence of improved flap survival. These results are encouraging regarding the use of monocytes as a potential method of improving vascularization of ischemic tissue. Laryngoscope, 2010.
What a manager learned and how he learned it
Authors: Drath Wilfred H. , Kaplan Robert E.
Published: July 2010

The use of realistic behavioral simulation for management training is growing. Perhaps the most often asked questions about such simulations are: How do they work? And what can managers learn from them? The authors attempt to answer these questions in narrative from by following one manager in his search for self‐discovery and understanding during the Center's Looking Glass simulation.
Rescuing derailed executives
Authors: Lombardo Michael M. , Eichinger Robert W.
Published: July 2010

A staggering waste of talent and money, derailment is an enormous setback that in many cases can be reversed.
Leadership template: Road map for managers
Authors: Fairhead Anthony J.
Published: July 2010

What might happen when promising managers plan their development in terms of challenging assignments, leadership qualities, and the avoidance of derailment? A card sort technique developed by the authors at Syntex Corp. is beginning to give answers that are leading managers to a broader view of their development.
In Situ X‐Ray Scattering Studies of Poly(ε‐caprolactone) Networks with Grafted Poly(ethylene glycol) Chains to Investigate Structural Changes during Dual‐ and Triple‐Shape Effect
Authors: Wagermaier Wolfgang , Zander Thomas , Hofmann Dieter , Kratz Karl , Narendra Kumar U. , Lendlein Andreas
Published: July 2010

The dual‐ and triple‐shape effects of multiphase polymer networks that contain two crystallizable chain segments have been assessed in situ by combining X‐ray measurements with thermomechanical investigations. The studied polymer, named CLEG, is a multiphase polymer network of crystallizable poly(ε‐caprolactone) (PCL) with grafted poly(ethylene glycol) (PEG) side chains. Wide‐angle (WAXS) and small‐angle X‐ray scattering (SAXS) measurements were combined with temperature‐controlled in situ tensile testing experiments. This integrated approach enables systematic investigation and interpretation of relevant structural features during the programming procedures and the thermally‐induced recovery process. Main results concern the combined effect of PCL and PEG crystals on shape fixation, the specific role of low‐melting PCL crystallites in the fixation of the low temperature temporary shape, and the different orientation behavior of PCL and PEG crystals during certain stages of the programming procedure. These results demonstrate that crystal orientation effects are dominant for the PCL crystals. The effects of the low temperature PCL crystals could only be investigated when synchrotron radiation was applied. These findings indicate the great potential of in situ X‐ray investigations for the creation of design‐relevant knowledge about the microscopic foundations of dual‐ and triple‐shape effects in appropriate polymer systems.

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Durchblick im Treffer‐Dschungel
Authors: Lippold Björn
Published: July 2010

Ein Suchbegriff — eine Million Treffer? Suchmaschinen mit zusätzlichen Filtern schränken das Ergebnis ein. Andere Suchmaschinen erkennen Zusammenhänge und beantworten Fragen.
Fakten und Trends: Chemiestudiengänge 2009
Authors: Schmitz Karin
Published: July 2010

Die Gesellschaft Deutscher Chemiker hat auch 2009 umfangreiche statistische Daten zu den Chemiestudiengängen erhoben. Sowohl die Zahl der Studienanfänger als auch die der Absolventen stieg gegenüber dem Vorjahr. Fast alle Bachelor‐Absolventen an Universitäten und etwa die Hälfte an Fachhochschulen schließen ein Master‐Studium an. An den Universitäten ist der Trend zur Promotion ungebrochen. Der Berufseinstieg war 2009 erwartungsgemäß schwieriger als in den Vorjahren. Die Wirtschaftskrise zeigte sich vor allem in einem Anstieg der befristeten Arbeitsverhältnisse.
Adjustment time and optimal control of neoclassical monetary growth models
Authors: Lewis Stephen D.
Published: July 2010

The problem of adjustment time in neoclassical monetary growth models is examined. Comparisons are made with the neoclassical growth model without money. Discretionary monetary and fiscal policies of a ‘bang‐bang’ type based upon Pontryagin's minimum principle and the ‘minimum‐time’ problem are derived by computer simulation since the models are non‐linear and except in trivial cases cannot be solved analytically. The effectiveness of policies in reducing adjustment time between equilibria is explored. These policies provide for increased confidence in the relevance of comparative static predictions derived from the type of models studied.
Optimal parameter estimation for basic problems of economic operation in electric power systems
Authors: El‐Hawary M. E. , Mansour S. Y.
Published: July 2010

The paper treats the problem of optimal parameter estimation for some basic models commonly used in conjunction with optimal economic operation studies in integrated electric power systems. Three well‐known parameter estimation algorithms are considered for this purpose. The weighted least‐squares, Gauss‐Newton, and Powell's regression algorithms are utilized to obtain optimal parameters for the fuel cost model of thermal generating sources, active power loss model for the electric network, as well as the active‐reactive power loss models. Performance comparisons using some test systems show that the Powell's regression results provide satisfactory optimal estimates.
Unimodal and bimodal optimal design of extensible arches with respect to buckling and vibrations
Authors: Blachut Jan , Gajewski Antoni
Published: July 2010

The problem of determining the optimal cross‐sectional area function along an extensible arch so as to minimize the total volume under given external pressure, fixed frequency, and geometrical constraints is investigated by use of the Pontryagin maximum principle. The optimal design of a clamped‐clamped arch is presented in detail. Optimization with respect to buckling load is also considered.
A Two‐Level optimal final‐value control system for non‐linear plants realized with mini/micro computers
Authors: Asselmeyer B.
Published: July 2010

A two‐level approach for optimal final‐value control of non‐linear systems is considered. On the higher level, an on‐line optimization (using a Ritz parameterization of the control functions1) is performed during each major sampling interval in order to compute the control functions for the next intervals. On the lower level, an explicit model‐following control is used with a minor sampling interval. This allows, even for heavily disturbed systems, sufficiently long major intervals for the on‐line optimization. An ammonia reactor2 is used as an example, and the application of this procedure is discussed. A realization of the controller using a hierarchical computer configuration gives an indication that, with a reasonable amount of hardware, sampling intervals of about one minute for the on‐line optimization and well below one second for the model‐following control may be obtained.
Optimal control of non‐linear advertising models with replenishable budget
Authors: Hartl Richard
Published: July 2010

This paper deals with an optimal advertising model with two state variables. The revenue and efficiency functions are concave. The aim is to choose the rate of advertising expenditures over time in a way that maximizes the present value of net profit streams over an infinite horizon subject to a replenishable budget. It is shown that the optimal advertising expenditures start at a high level and decrease over time if the initial stock of goodwill is low. Low initial budget as well as low initial stock of goodwill can cause shortness of budget. It turns out that, in contrast to comparable linear models, the remaining budget is always positive.
Optimal Coatings, Bang‐Bang Controls, And Gradient Techniques
Authors: Hager William W. , Rostamian Rouben
Published: July 2010

A model for a viscoelastic coating is derived and the coating reflectivity is determined. A coating which minimizes the reflection of sound waves is partly bang‐bang and partly singular. A new gradient type algorithm is presented for computing the optimal control. Formulae for the gradient of the cost in optimal control are derived in various settings.