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Studies of CEO dismissal and founder-CEO departure (Shen and Cannella [2001, 2002] and Boeker and Karichalil [2002]) have identified numerous factors that may influence a board of directors' decision to [...]

The interaction of national culture and work role is studied by comparing and contrasting variations in motivational needs among US and Israeli entrepreneurs and managers. The results show that there is indeed a correlation between the two concepts of Israel and US as regards culture and entrepreneur and manager as regards work roles. The study is important as a springboard for further research on US transnational companies focusing on managers as well as entrepreneurs.

This work presents ferrate(VI) (FeVIO42–, FeVI) oxidation of a wide range of sulfonamide antibiotics (SAs) containing five- and six-membered heterocyclic moieties (R) in their molecular structures. Kinetics measurements of the reactions between FeVIand SAs at different pH (6.5–10.0) give species-specific second-order rate constants, k5and k6of the reactions of protonated FeVI(HFeO4–) and unprotonated FeVI(FeVIO42–) with protonated SAs (HX), respectively. The values of k5varied from (1.2 ± 0.1) × 103to (2.2 ± 0.2) × 104M–1s–1, while the range of k6was from (1.1 ± 0.1) × 102to (1.0 ± 0.1) × 103M–1s–1for different SAs. The transformation products of reaction between FeVIand sulfadiazine (SDZ, contains a six-membered R) include SO2extrusion oxidized products (OPs) and aniline hydroxylated products. Comparatively, oxidation of sulfisoxazole (SIZ, a five-membered R) by FeVIhas OPs that have no SO2extrusion in their structures. Density functional theory calculations are performed to demonstrate SO2extrusion in oxidation of SDZ by FeVI. The detailed mechanisms of oxidation are proposed to describe the differences in the oxidation of six- and five-membered heterocyclic moieties (R) containing SAs (i.e., SDZ versus SIZ) by FeVI.

4-Aza-8-fluoroindolo[2,1-b]quinazoline-6,12-dione (4-aza-8-fluorotryptanthrin) was imaged via scanning tunneling microscopy and barrier height tunneling spectroscopy at the graphite–solution interface. Submolecular resolution was achieved for the apparent barrier height (ϕap) images and revealed that ϕapdisplays significant variation over the area of the molecule. Topographic effects and electrostatic potential effects were found to be insufficient to explain the behavior of the measured ϕapvariations. Specifically, where barrier height images were collected over regions of large molecular orbital (MO) wave function amplitudes, the measured ϕapdid not agree with either affecting phenomenon. The authors attribute the disparity to the fact that electron tunneling is orbital-mediated for these systems. Thus, the ϕapis dominated by the spatial disposition of the mediating MO in locations of large wave function amplitude. This hypothesis is corroborated by excellent agreement with a computational treatment that takes into account only the spatial disposition of the MO wave function. It is possible that these measurements could be used to predict molecular behaviors, especially when a redox event or electron coordination is involved.

Semiquantitative apparent tunneling barrier measurements were collected of stearic acid adsorbed onto highly oriented pyrolytic graphite from 1-phenyloctane. A detailed investigation of the topography revealed an interesting geometric phenomenon, namely, the observation of different conformers within a single monolayer; this phenomenon has not been previously reported, despite the large volume of work on these and similar systems in the literature. Apparent barrier height images showed two separate effects. The apparent barrier height map is dominated by the distribution of surface charge (as tracked by electrostatic potential) in regions where significant polarity exists (i.e., near the carboxyl groups). Conversely, in regions where there is little variation in electrostatic potential (i.e., near the interlaced alkane chains), the manifestation of the topography dominates the apparent barrier height. The electron tunneling involved in imaging these types of monolayers is not mediated by adlayer molecular orbitals since their energies fall outside of the Fermi levels of the substrate and the tip under the tunneling conditions described. These studies provide a basis for further investigations into barrier height tunneling spectroscopy of molecular monolayers on graphite.

Scanning tunneling microscopy was used to observe 8-fluorotryptanthrin, an analogue of indolo[2,1- b]quinazolin-6,12-dione (tryptanthrin). Images were collected of molecules adsorbed at the solution−HOPG (highly oriented pyrolytic graphite) interface, displaying submolecular resolution. Measurements at negative bias are provided where individual molecular orbital lobes were observed, correlating directly to the density functional theory model of the highest occupied molecular orbital (HOMO). Molecules measured approximately 1.3 nm in length. Separate surface domains, displaying an offset of approximately 0.36 nm, were observed from parallel rows of molecules. Two-dimensional enantiomers were observed occupying the domain boundary. Raised features observed in the image suggest that molecules of 8-fluorotryptanthrin experience adsorption-induced stereoisomerization, similar to its parent compound.

A bicyclic decapeptide, GCN4brM1, which was designed to be a helix-locked analog of the DNA-binding basic region from the yeast transcription factor GCN4, was synthesized and characterized using circular dichroism (CD) spectropolarimetry and ¹H-NMR. This peptide has two Lysⁱ, Aspⁱ⁺⁴ side chain lactam bridges incorporated into its structure in overlapping positions in the peptide chain, linking residues 3 and 7 and residues 4 and 8. CD spectra of GCN4brM1 in aqueous solution are consistent with the expected helical conformation, and indicate that this conformation is remarkably resistant to heat denaturation and is essentially unchanged by addition of 50% (v/v) trifluoroethanol (TFE) as cosolvent. NMR spectra measured in aqueous solution at −5°C show long-range nuclear Overhauser effects (NOEs) that are consistent with anα-helical conformation throughout the peptide structure. The measured ³J_HN coupling constants are also in agreement with an α-helical structure. Extremely slow proton-deuterium exchange rates measured for backbone amides in the middle of the peptide indicate that this helix is highly stabilized and rarely unfolds within the side chain bridged sequence. NOE-constrained molecular dynamics simulations gave rise to a single family of converged structures that are fully α-helical throughout the GCN4brM1 backbone, and show a single, well-defined conformation for the two side chain bridges. This study demonstrates that two overlapping Lysⁱ, Aspⁱ⁺⁴ lactam bridges, positioned in consecutive residue positions in a hexapeptide segment, form a rigid α-helical structure in aqueous solution that is propagated in both the N-terminal and C-terminal directions.

Zusamenfassung: Fragestellung. Die Klimatisierung der Narkosegase wird in erheblichem Maß vom Frischgasfluss beeinflusst und ist bei Durchführung von Niedrigflussnarkosen besser als bei hohem Flow. Feuchte und Wärme der Gase werden darüber hinaus aber auch von den Wärmeverlusten und entsprechender Wasserkondensation in den Atemschläuchen beeinflusst, die ihrerseits vom technischen Design und den Materialeigenschaften der Atemschläuche abhängen. Mit dieser prospektiven Studie sollte untersucht werden, 1. inwiefern bei Durchführung von Niedrigflussnarkosen die Klimatisierung der Narkosegase im klinischen Routinebterieb durch das technische Design der Schlauchsysteme beeinflusst wird. Des weiteren sollte 2. untersucht werden, ob bei Einsatz des Schlauchsystems, mit dem optimale Klimatisierungseffekte erreicht werden, diese sich auch bei Erhöhung der Frischgasflows noch realisieren lassen. Methodik. Drei unterschiedliche Schlauchsysteme, das konventionelle Doppelschlauchsystem, ein koaxiales Schlauchsystem und ein Doppelschlauchsystem mit beheizten Schläuchen wurden bei der Durchführung von Minimal-flow-Anästhesien mit einem Frischgasfluss von 0,5 l/min an einem Dräger Cicero EM Narkosegerät eingesetzt. Die Atemgastemperatur und die absolute Feuchte im Inspirationsschenkel des jeweiligen Schlauchsystems wurden sowohl Atemsystem- als auch tubuskonnektornah gemessen. Die besten Klimatisierungseffekte wurden bei Einsatz der beheizten Schläuche erreicht. Mit diesem Schlauchsystem wurden deshalb weitere Messungen der inspiratorischen Atemgasfeuchte und -wärme mit Frischgasflows von 1,0, 2,0 und 4,4 l/min durchgeführt. Die Messungen in allen Gruppen erfolgten während der Durchführung von Inhalationsnarkosen von zumindest 45 min Dauer an jeweils acht Arbeitstagen. Ergebnisse. Bei der Durchführung von Minimal-flow-Narkosen wurden gleichermaßen während des Ablaufs der Arbeitstage mit allen Schlauchsystemen tubuskonnektornah Feuchtewerte zwischen 17 und 30 mgH2O/l erreicht. Nur während der ersten Narkosen zu Beginn der Arbeitstage wurde eine kurze zeitliche Verzögerung von 15 bis 30 min bis zum Erreichen einer Feuchte von zumindest 17 mgH2O/l beobachtet. Bei Einsatz der beheizten Schlauchsysteme wurden gehäuft auch Feuchtewerte über 30 mgH2O/l gemessen. Die tubuskonnektornah gemessenen Atemgastemperaturen waren bei Einsatz des konventionellen und des koaxialen Schlauchsystems während der Durchführung von Minmal-flow-Narkosen mit Werten zwischen 23 und 30°C in einem akzeptablen Bereich. Bei Einsatz der beheizten Schläuche aber waren die inspiratorischen Atemgastemperaturen mit Werten zwischen 28 bis 32 °C deutlich höher und nahezu optimal. Während der Durchführung von Minimal-flow-Narkosen waren somit bei Einsatz beheizter Schlauchsysteme die beste Klimatisierung der Atemgase zu erreichen. Mit diesem Atemsystem wurden deshalb weitere Messreihen mit zunehmenden Frischgasflows von 1,0, 2,0 und 4,4 l/min durchgeführt. Während bei einem Frischgasfluss von 1,0 l/min die Atemgasklimatisierung weiterhin optimal ist, fällt bei weiterer Steigerung des Frischgasflows auf 2,0 l/min die Feuchte drastisch auf Werte unter 17 mgH2O/l, bei einem Flow von 4,4 l/min sogar auf Werte um nur 10 mgH2O/l ab. Dagegen erwiesen sich die Atemgastemperaturen bei Einsatz beheizter Schläuche als weitestgehend flowunabhängig und lagen immer, auch bei einem Flow von 4,4 l/min, um 28–32°C. Schlussfolgerungen. Mit konventionellen und koaxialen Schlauchsystemen wird bei der Durchführung von Minimal-flow-Anästhesien eine zwar nicht optimale, aber ausreichende Atemgasklimatisierung erreicht. Der Einsatz koaxialer Systeme scheint im Vergleich zum konventionellen Doppelschlauchsystem nur bei langdauernden Narkosen zu einer weiteren Verbesserung der Klimatisierung zu führen. Während des klinischen Routinebetriebs sind beide Systeme bezüglich der Klimatisierungseffekte als gleichwertig anzusehen. Bei Einsatz beheizter Schläuche ist unter den Bedingungen der Minimal-flow-Anästhesie die Klimatisierung der Atemgase deutlich besser als bei Einsatz konventioneller oder koaxialer Schlauchsysteme. Es werden nicht nur ausreichende, sondern gar optimale Feuchte- und Wärmewerte erreicht. Diese optimale Klimatisierung wird aber nur bei Durchführung von Niedrigflussverfahren realisiert, dann also, wenn der Frischgasflow nicht größer als 1 l/min ist. Bei höheren Frischgasflows nimmt die Feuchte der Atemgase drastisch ab, während die Atemgastemperaturen hoch bleiben. Es ist anzunehmen, dass die Beatmung mit warmem und trockenem Atemgas zu verstärkter Austrocknung des Atemwegsepithels der unteren Atemwege führt. Beheizte Schläuche sollten deshalb nur bei Durchführung von Niedrigflussnarkosen eingesetzt werden. Während die Feuchte der Atemgase im wesentlichen von der Frischgasflussrate bestimmt wird, hängt die Atemgastemperatur im wesentlichen vom Wärmeverlust am Inspirationsschenkel des Patientenschlauchsystems ab.

This analysis was undertaken to see whether or not previous successful breastfeeding has any influence on subsequent breastfeeding behavior. Lactational outcomes were compared between those with and without breastfeeding experience. Methods: Amount of breast milk transferred, frequency of breastfeeding, and time spent on the breast, as well as infant's weight, were recorded on days 15,45, 90, 180, 270, and 360 postpartum in 30 primiparae and 30 multiparae. Outcomes of the primiparae were found to be similar to those of the more experienced breastfeeding multiparous mothers with respect to infant growth, amount of breast milk transferred, and the frequency of breastfeeding or number of attachments to the breast. Though primiparae took somewhat longer to transfer similar amounts of breast milk to their infants during the initial 45 to 90 days postpartum, feed duration after 90 days was similar to that of the multiparae. Lactation performance of the rural northern Thai mothers in our sample was highly successful with or without previous breastfeeding experience. It may be that a cultural pattern of breastfeeding on demand, strong family support, and traditional practices that encourage close contact between mother and her newborn compensate for the absence of lactational experience. Unlike reports from Western countries, previous breastfeeding does not appear to be an important predictor of successful and prolonged breastfeeding in our population.

This study was undertaken to see whether tubal ligation performed within days postpartum, and associated with a delay in the initiation of breastfeeding, exerts a disruptive influence on successfully establishing lactation among the rural population of northern Thailand.

Urinary excretion of heparan sulphate proteoglycan (HSPG), the main anionic component of the glomerular basement membrane (GBM), was estimated in 30 adolescents and young adults with insulin dependent diabetes (IDDM), 10 with microalbuminuria and 20 sex matched, diabetic controls of similar age without evidence of microalbuminuria. A further 10 non-diabetic control subjects were also examined. Both groups of patients with diabetes had significantly elevated excretion of HSPG when compared to normal individuals. There was no difference in HSPG excretion between diabetic subjects with and without microalbuminuria.

The authors describe the development of a Doppler ultrasound flow transducer used in conjunction with a zero-crossing demodulator for breast milk flow measurement. The results of the preliminary evaluation in vitro are presented in the paper. The design is at present being minaturised in order to use the transducer for in vivo measurement.

Frozen sections of human, calf, rabbit, rat, cat, dog, goat, lamb, and hog corneas were stained with various lectins using an avidin-biotin-peroxidase complex to study glycoconjugates of stromal matrix. Staining of the stromal matrix and keratocytes with an a-galactose-specific lectin, Griffoma simplicifolia I (GSA-I) was species-dependent. The stromal matrices of cat, dog, and hog corneas invariably reacted intensely with this lectin, whereas those of the human, calf, rabbit, rat, and lamb did not react. A positive reaction with GSA-I could be abolished in each instance by preincubation of the sections with a-galactosidase. The stromal matrices and keratocytes of all nine species reacted positiyely with wheat germ agglutinin, concanavalin A, and Ricinus communis agglutinin but did not react with soybean agglutinin. Results of this study may help select and appropriate animal model to further investigate human corneal stromal glycoconjugates.

Over a period of four years, seven of 110 maintenance henodialysis patients developed olecranon bursitis. In all patients it appeared in the arm on which AV access was constructed but one patient also had bilateral bursitis. None of the patients gave a history of trauma or gout. Despite similar clinical presentation, culture of bursal aspirate demonstrated septic bursitis in two patients. (One diabetic, the other on steroids). Sustained pressure on the olecranon bursa during maintenance hemodialysis and/or mild trauma in the anticoagulated state may be responsible for the lesion. Infection can occur in susceptible individuals despite no visible skin infection. Local steroid instillation and patient education to avoid putting pressure on bursa during dialysis was effective therapy in the aseptic group. Multiple aspirations and antibiotics were necessary in the septic group.

The amount of diagnostic radiation received by neonates at a large maternity hospital in 1982 was calculated. The risk of inducing neoplasia is unlikely to be greater than one in 280 000 for each radiograph of chest or abdomen. Provided that the exposure of the newborn to radiation at the John Radcliffe Hospital is typical of the rest of the country, and excluding cardiac catheterisation and computed tomography, we estimate that at most one to two cases of malignant disease per year may be caused by diagnostic radiation in the United Kingdom. Genetic risks appear to be negligible. The risks of not using radiography in newborn patients outweigh the risks of inducing malignant or genetic disease.

Confluent monolayer cultures of rabbit corneal endothelial and stromal cells were incubated independently with [35S]sulphate and [3H]glucosamine for 3 days. AFter incubation, labelled glycosaminoglycans were isolated from the growth medium and from a cellular fraction. These glycosaminoglycans were further characterized by DEAE-cellulose column chromatography and by sequential treatment with various glycosamino-glycan-degrading enzymes. Both endothelial and stromal cultures synthesized hyaluronic acid as the principal product. The cell fraction from the stromal cultures, however, had significantly less hyaluronic acid than that from the endothelial cultures. In addition, both types of cells synthesized a variety of sulphated glycosaminoglycans. The relative amounts of each sulphated glycosaminoglycan in the two cell lines were similar, with chondroitin 4-sulphate, chondroitin 6-sulphate and dermatan sulphate as the major components. Heparan sulphate was present in smaller amounts. Keratan sulphate was also identified, but only in very small amounts (1-3%). The presence of dermatan sulphate and the high content of hyaluronic acid are similar to the pattern of glycosaminoglycans seen in regenerating or developing tissues, including cornea.

Summary: Indirect test weighing (ITW), a new method for measuring nighttime breast milk intake, is based on separate weighings of the mother and infant at the start and end of the nighttime sleep period. All other incidental weight changes overnight are measured, so that the corrected infant's overnight weight gain and the mother's overnight weight loss are then accounted for by breast milk transfer and evaporative water loss (EWL) alone. The combined EWL is partitioned between mother and infant on the basis of metabolic body size (body weight raised to the power of 0.73). The infant's EWL is added onto the corrected overnight weight gain to give nighttime milk intake. A field validation study on 24 northern Thai infants, conducted in the subject's homes, in which ITW was compared with nighttime direct test weighing (DTW) on the same night, gives 95 confidence intervals for the method of × 39 g for a range of milk intakes of 77–344 g. Confidence intervals for estimates using feeding patterns alone, or multiplying 12 h intakes by a constant, range from × 104 to 180 g, indicating that these methods are insufficiently accurate for individual estimates.

A British Paediatric Association Surveillance Unit* study of neonatal diabetes determined a national incidence of 1 in 400,000 live births. Additional cases of transient neonatal diabetes were collected retrospectively. Most cases were of low birthweight at term: none had evidence of an autoimmune aetiopathogenesis. The median requirement for exogenous insulin treatment was three months. A significant number of cases developed type 2 diabetes in later life. Three of the 11 cases were found to have paternal uniparental isodisomy of chromosome 6. A further patient carried an unbalanced duplication of 6q 22-23, inherited from the father, which localised a potentially imprinted gene for diabetes to this region. The fact that low birthweight predisposes to type 2 diabetes in later life is well established, but a genetic defect that may relate both to intrauterine growth failure and the development of type 2 diabetes in later life has now been identified.

Numerical simulations with a monotonicity preserving flow solver have been performed to study shock diffraction phenomena and shock wave generated vorticity. The computations were performed using the conservative Finite Element Method-Flux Corrected Transport (FEM-FCT) scheme, which has been shown to have an excellent predictive capability for various compressible flows with both strong and weak shocks. An adaptive unstructured methodology based on adapting to high density and entropy gradients was used in conjunction with a conservative shock-capturing scheme to adequately resolve strong and weak flowfield gradients. The chief interest was the formation of vorticity arising from shock wave propagation over a sharp corner and the high accuracy and resolution of the interacting compressible wave features. Numerical simulations were compared with previous experimental results and exhibited remarkably good agreement in terms of compressible wave propagation, as well as vorticity development and transport. The computations also allowed insight into the fundamental fluid dynamics, specifically shock diffraction, vortex convection and shock-vortex interactions.

The replication origins of three large Bacillus thuringiensis plasmids, derived from B. thuringiensis HD263 subsp. kurstaki, have been cloned in Escherichia coli and sequenced. The replication origins, designated ori 43, ori 44, and ori 60, were isolated from plasmids of 43, 44, and 60 MDa, respectively. Each cloned replication origin exhibits incompatibility with the resident B. thuringiensis plasmid from which it was derived. Recombinant plasmids containing the three replication origins varied in their ability to transform strains of B. thuringiensis, Bacillus megaterium, and Bacillus subtilis. Analysis of the derived nucleotide and amino acid sequences indicates that the replication origins are nonhomologous, implying independent derivations. No significant homology was found to published sequences of replication origins derived from the single-stranded DNA plasmids of gram-positive bacteria, and shuttle vectors containing the three replication origins do not appear to generate single-stranded DNA intermediates in B. thuringiensis. The replication origin regions of the large plasmids are each characterized by a single open reading frame whose product is essential for replication in B. thuringiensis. The putative replication protein of ori 60 exhibits partial homology to the RepA protein of the Bacillus stearothermophilus plasmid pTB19. The putative replication protein of ori 43 exhibits weak but extensive homology to the replication proteins of several streptococcal plasmids, including the open reading frame E replication protein of the conjugative plasmid pAM beta 1. The nucleotide sequence of ori 44 and the amino acid sequence of its putative replication protein appear to be nonhomologous to other published replication origin sequences.

Numerous papers have purported the need for life span education, yet few have examined the attitudes of older citizens toward lifelong learning. To determine why they were not attending a free audit program at the university and to ascertain their attitudes toward education for the elderly, 99 subjects aged 62 and older (M. = 74.6) were interviewed. The systematic sample chosen from membership lists of senior citizen groups yielded 34 men and 65 women. Interviews utilized a survey questionnaire. The analysis compared those who were and were not interested in the program.Results indicated that 68% (N = 65) of the subjects were not interested in attending university classes. The 32% (N = 31) who answered "yes" or "maybe" were significantly younger than those who were not interested; the two groups did not differ significantly on the other variables measured (sex, previous education, occupation, daily activities, attitude toward education for self and other older persons, etc.). Furthermore, only one subject actually enrolled in the university in the subsequent semester.The findings fail to support the thesis that "education begets education." However, it should be noted that subjects indicated that "living is learning," and while formal education is acceptable for the elderly, it is not necessary for learning.

Abstract.: A non-equilibrium reacting flow methodology has been added to a conservative, monotonic, compressible flow solver to allow numerical simulations of gas detonations. This flow solver incorporates unstructured dynamically adaptive meshes with the Finite Element Method – Flux Corrected Transport (FEM-FCT) scheme, which has shown excellent predictive capability of various non-reacting compressible flows. A two-step induction parameter model was used to model the combustion of the gas phase coupled with an energy release equation which was simulated with a point implicit finite element scheme. This combustion model was then applied to a two-dimensional detonation test case of a hypothetical fuel:oxygen mixture. The detonation simulation yielded two transverse waves which continued to propagate. This feature and the detonation shock speed mean and fluctuations were found to be grid-independent based on a resolution of about twenty elements within the average induction length. The resolution was efficiently achieved with the unstructured dynamically adaptive finite elements, which were three orders of magnitude less in number then required for uniform discretization.

35S-labeled Pseudomonas aeruginosa isolates were shown to bind to neutral glycosphingolipids (NGSLs) of rabbit corneal epithelia in culture by a thin-layer chromatogram overlay procedure. The lipids of the corneal epithelial cells grown in culture were extracted and partitioned into a chloroform-rich lower phase containing NGSLs and an aqueous upper phase containing gangliosides. By using a dot-blot assay, at least six times more radiolabeled P. aeruginosa isolates were shown to bind to the lipids in the lower phase compared with those in the upper phase. Thin-layer chromatography of the lower-phase lipids followed by staining with an orcinol spray revealed at least 10 NGSL components and several fast-migrating, nonglycosylated neutral lipid components (including cholesterol). 35S-labeled P. aeruginosa was shown to bind to NGSL components 1, 2, 5, 6, and 9. P. aeruginosa-reactive NGSL components 6 and 9 migrated with chromatographic mobilities similar to those of the standards ceramide trihexoside (CT) and ceramide monohexoside, respectively. Components 1 and 2 migrated slightly ahead of asialo GM1, and component 5 migrated faster than globoside but slower than CT. Among the various standards tested, P. aeruginosa bound to asialo GM1 and, to a lesser extent, to ceramide dihexoside and CT but not to GM1, GD1A, GM3, or ceramide monohexoside. It remains to be determined whether any of the five P. aeruginosa-reactive NGSL components of corneal epithelium identified in this study plays a role in the development of corneal infection. However, we have previously shown that component 9, one of the five P. aeruginosa-reactive NGSL components identified in this study, is present in significantly greater amounts in migrating epithelia than it is in nonmigrating epithelia (N. Panjwani, G. Michalopoulos, J. Song, G. Yogeeswaran, and J. Baum, Invest. Ophthalmol. Vis. Sci., in press). This may prove to be of biological significance because it is generally believed that traumatized (migrating) epithelia are more susceptible to infection than normal (nonmigrating) epithelia are.

A random sample of 52 mothers and infants from a rural area of Northern Thailand were studied in their homes for 48 h. Infants were breast fed on demand. Daytime feeds were test weighed with electronic averaging balances and nighttime intake estimated using a new method, Indirect Test Weighing (23,24). All feeds, both day and night, were timed to the nearest minute. Other variables measured by direct observation were infant weight, and supplementary food and water intake. Mean 24-h breast milk intake was 579 g (range 78–1,011 g) with a median between day coefficient of variation of 8.8. The proportion of 24-h breast milk intake consumed at night ranged from 8 to 91, and increased with increasing infant age. Significant positive associations were found between breast milk intake, and sucking time and infant weight. There were significant negative associations between breast milk intake and age, and supplementary food and water intake.

The passage of planar shocks in a dusty gas was investigated to note effects due to particle loading and initial shock Mach number. Two-phase flow equations have been added to a conservative, monotonic flow solver to allow study of compressible particle and droplet flows, which are of importance for shock propagation in two-phase flows and spray propulsion systems. The formulation developed herein employed a conservative Eulerian treatment for the gas and particle phases. The computations were performed using the finite element method-flux corrected transport (FEM-FCT) scheme, which has shown excellent predictive capability of various compressible flows which include both strong and weak shocks. The flux limiting technique was modified to provide monotonic particle velocity fields to increase the scheme's computational stability. Adaptive unstructured methodology based on adapting to high gradients of both the fluid and particle densities was used in conjunction with the conservative shock-capturing scheme to adequately resolve strong flowfield gradients. The shock attenuation of this scheme was then compared with previous experimental and numerical results and was found to yield robust predictions. Various interphase coupling terms were also considered to note their effect on the shock attenuation.

Zusammenfassung: Volatile Ansthetika werden an trockenem Atemkalk teilweise zu Kohlenmonoxid umgesetzt. Im Laborexperiment wurde frischer, ungebrauchter Atemkalk mit einem konstanten Flow von 1 l/min Sauerstoff ber 120 h getrocknet. Der Gewichtsverlust durch Trocknung betrug 17,1%. Halothan, Enfluran und Isofluran wurden in Konzentrationen von jeweils 2 Vol.-% in 0,5 l/min Sauerstoff durch den trockenen Atemkalk geleitet. Unmittelbar nach Einleiten der Ansthetika wurde im Atemkalk Kohlenmonoxid gebildet. Die geringsten Konzentrationen wurden unter Halothan (400 ppm) bestimmt. Bedeutend mehr CO fiel bei der Reaktion zwischen Atemkalk und Enfluran (3500 ppm) bzw. Isofluran (3800 ppm) an. Im Atemkalk kam es whrend der CO-Produktion zu einem Anstieg der Temperatur bis auf 52,1 C. Whrend dieser Phase wurde Halothan, nicht aber Enfluran oder Isofluran, vollstndig vom Atemkalk absorbiert. Inspiratorische CO-Konzentrationen von 4000 ppm knnen bereits nach kurzer Expositionsdauer zu einer klinisch relevanten COHb-Bildung fhren. Um der Gefahr einer Carboxyhmoglobinbildung entgegenzuwirken, mu die akzidentelle Austrocknung des Atemkalks deshalb unbedingt vermieden werden.

Abstract.: It is a strange contradiction that increasingly sophisticated anaesthesia machines are developed meeting all requirements for rebreathing techniques and the highest safety standards, but the usual anaesthetic management is still based on the use of fresh gas flows that preclude substantial rebreathing. The advantages of rebreathing can only be realised if low-flow anaesthesia techniques are adopted. Increasing acceptance of these methods is due to the availability of comprehensive anaesthetic gas monitoring. Different techniques of low-flow anaesthesia, the characteristic features, technical requirements, and considerations concerning their performance and contraindications are discussed. This paper presents a topic that is left unmentioned by most anaesthesia textbooks. The use of new inhalational anaesthetics such as desflurane that require comparatively high concentrations, or even xenon, will motivate to sparing use. Increasingly stringent health and safety regulations as well as sharpened ecological awareness will prompt anaesthetists to minimise all anaesthetic gas emission according to the possibilities of available equipment. Last but not least, the demand for economical working methods will be an argument for applying low-flow anaesthesia techniques.

A study at SCF-CI level has been performed on the water dimer, with a [541|31] basis set. The effects of the correlation energy, basis set superposition error (BSSE) and Davidson correction were investigated. Maintaining the experimental water geometry, several sections of the energy surface were calculated. They show only one minimum energy structure, the linear trans dimer, in agreement with experiment. The linear cis and bifurcated forms are found to be unstable.The Davidson correction has a minimal effect on the energy surface. The correlation energy and BSSE are important, being ∼ 10 per cent or more of the total interaction energy, and are distance dependent. They also show a complex angular dependence. As the BSSE size is an indication of the basis set quality, only those surface features virtually unaffected by the BSSE correction can be regarded as reliable. Here, these features are the angular parameters of the minimum, the O-O stretching frequency and the general surface shape.Basis sets with negligible BSSE are desirable, and are at present possible for small systems at SCF level, but not at the CI level [20, 21]. Therefore, current use of this method to provide data for improving empirical energy potentials of systems with non-negligible dispersion energies is unlikely to be successful.

DNase I hypersensitive regions were mapped within the 17.3-kilobase qa (quinic acid) gene cluster of Neurospora crassa. The 5'-flanking regions of the five qa structural genes and the two qa regulatory genes each contain DNase I hypersensitive sites under noninducing conditions and generally exhibit increases in DNase I cleavage upon induction of transcription with quinic acid. The two large intergenic regions of the qa gene cluster appear to be similarly organized with respect to the positions of constitutive and inducible DNase I hypersensitive sites. Inducible hypersensitive sites on the 5' side of one qa gene, qa-x, appear to be differentially regulated. Employing these and previously published data, we have identified a conserved sequence element that may mediate the activator function of the qa-1F regulatory gene. Variants of the 16-base-pair consensus sequence are consistently found within DNase I-protected regions adjacent to inducible DNase I hypersensitive sites within the gene cluster.

The qa-1F regulatory gene of Neurospora crassa encodes an activator protein required for quinic acid induction of transcription in the qa gene cluster. This activator protein was expressed in insect cell culture with a baculovirus expression vector. The activator binds to 13 sites in the gene cluster that are characterized by a conserved 16-base-pair sequence of partial dyad symmetry. One site is located between the divergently transcribed qa-1F and qa-1S regulatory genes, corroborating prior evidence that qa-1F is autoregulated and controls expression of the qa-1S repressor. Multiple upstream sites located at variable positions 5' to the qa structural genes appear to allow for greater transcriptional control by qa-1F. Full-length and truncated activator peptides were synthesized in vitro, and the DNA-binding domain was localized to the first 183 amino acids. A 28-amino acid sequence within this region shows striking homology to N-terminal sequences from other lower-eucaryotic activator proteins. A qa-1F(Ts) mutation is located within this putative DNA-binding domain.

By use of a thin-layer chromatogram (TLC) overlay procedure, 35S-labeled acanthamoebae were shown to bind to seven glycolipids of rabbit corneal epithelium. Corneal epithelial cells were grown in culture and were subjected to Folch extraction to isolate a chloroform-rich lower phase containing neutral glycosphingolipids (NGSL) and an aqueous upper phase containing gangliosides, i.e., sialic acid-containing glycolipids. Thin-layer chromatography of the upper phase revealed the presence of 10 ganglioside components. Acanthamoebae were shown to bind to four of these components, referred to as 2, 3, 6, and 7. On TLC plates, ganglioside components 2 and 3 migrated slightly ahead of the glycolipid standard GD1a, component 7 comigrated with standard GM3, and component 6 migrated a little more slowly than GM3. Likewise, of the 10 NGSL known to be present in the lower phase, acanthamoebae bound to components 1, 5, and 6. NGSL components 1, 5, and 6 migrated on TLC plates with relative mobilities similar to those of standards asialo GM1, asialo GM2, and ceramidetrihexoside, respectively. We propose that one or more of the Acanthamoeba-reactive glycolipids of corneal epithelium identified in this study may play a role in the pathogenesis of Acanthamoeba keratitis by mediating the adherence of the parasites to the cornea.

Initial interest in the behaviour of human parents with their newborn infants has stimulated observations on the rearing patterns of various mammalian species, in particular those of the domestic goat. Domestic goats normally rear their young within a specific family structure. The suckling relationship between mother and young is typically limited to a particular mother and her kid and any attempt for a foreign kid to suck may result in the mother violently repelling the alien offspring. The experience of the mother goat immediately following birth is critical to the development of this pattern of rearing behaviour. Hersher, Moore & Richmond (1958) separated 24 domestic nannies from their newborn kids for periods of ½1 h immediately after birth. The kids were then permitted or helped to suck on their own mothers teats when mother and kid were reunited. These goat pairs were compared with 21 control animals after 2 and 3 months. At this assessment the following significant differences from behaviour of mothers not separated from their kids were found during the period of observation: the separated goats (a) nursed their own kids for significantly shorter periods, (b) nursed alien kids for longer periods and (c) spent less time butting alien kids. None of the mothers in either group was noted to butt their own kids.

Twenty-four hour profiles of plasma C-peptide an index of endogenous insulin secretion, were performed in 15 Type 1 (insulin-dependent) diabetic children. Plasma C-peptide was detectable in six children, of whom four (‘C-peptide producers’) had peak values above normal fasting levels. In each of the six children with residual B cell function, there was a close correlation between plasma C-peptide and simultaneous blood glucose (r> 0.50, p< 0.05). Post-breakfast peak blood glucose was 10.2 ± 1.7 mmol/l (mean ±SEM) in the ‘C-peptide producers’ and 18.7 ± 1.7 mmol/l in the 11 children with low or no detectable C-peptide. Mean M-value, an index of deviation from an ideal blood glucose, was lower in the ‘C-peptide producers’ (p<0.05). It is concluded that residual functioning B cells in diabetic children behave physiologically in that insulin secretion fluctuates in accordance with the prevailing blood glucose; and that the pattern of action of injected insulin is more critical in non-C-peptide producers who lack the post-prandial dampening effect provided by residual endogenous insulin secretion.

In 1973 a children's diabetic clinic was established in Oxford. An analysis has been made of the effects this has had on the pattern of emergency admissions classified as severe hyperglycaemia (A), moderate hyperglycaemia (B) and hypoglycaemia (C). A comparison of the admission rate per “diabetic year” over the four years before and the three years after the children's clinic was established showed a significant decrease in admission rate for all hyperglycaemic admissions (p<0.05). This decrease was shown to be mainly due to a reduction in admissions with severe hyperglycaemia (A) (p<0.01), there being no significant change in admission rate for moderate hyperglycaemia (B). There was no significant change in admission rate for hypoglycaemia (C).

Treatment failure is usually understood as a problem of patient compliance. This paper suggests another approach: to see this problem as resulting from a difference in the goals of the two parties involved, the doctor and the patient. Comparison was made between the goals of doctors and those of parents in treating children with diabetes. Significant differences emerged between the goals. Parents' goals of treatment were governed more by avoidance of the short-term threat of diabetes (hypoglycemia); doctors' goals more by the long-term threat of diabetes (diabetic complications). The outcome of treatment (diabetic control) was more closely related to parents' than doctors' goals of control. These results indicate that doctors and patients do not always share the same goals in treatment. It is suggested that a more effective clinical alliance would result if the goals of the clinical team were at least made explicit, even if they were not always shared.

Desfluran ist wegen seiner guten Steuerbarkeit ein gerade für die Durchführung von Niedrigflußnarkosen besonders geeignetes Inhalationsanästhetikum. Bereits nach einer nur 10 min dauernden Initialphase mit hohem Frischgasfluß kann der Flow schon vermindert werden. Die zu diesem Zeitpunkt erreichte inspiratorische Desflurankonzentration, die etwa 90% der Frischgaskonzentration beträgt, kann bei der Durchführung der Low Flow-Anästhesie (1 l/min) ohne Veränderung der Verdampfereinstellung aufrechterhalten werden, bei Minimal Flow-Anästhesie (0,5 l/min) hingegen ist eine Erhöhung der Verdampfereinstellung auf einen Wert 1–2% höher als den angestrebten inspiratorischen Sollwert erforderlich. Wird die hohe, vom Desfluranverdampfer abgegebene Maximalkonzentration von 18% genutzt, läßt sich, bei gleichzeitig substanzspezifisch geringer individueller Narkosemittelaufnahme durch den Patienten, die inspiratorische Konzentration bei einem Flow von 0,5 l/min in nur 8 min um etwa 5% erhöhen. Die Kohlenmonoxidhämoglobinkonzentration nimmt in 1 h von einem präoperativen Wert von 2, 13±1,05% auf 1,42±1,01% ab. Werden alle Maßnahmen getroffen, ein unbeabsichtigtes Austrocknen des Atemkalks sicher zu vermeiden, besteht auch bei Durchführung von Niedrigflußnarkosen mit Desfluran kein erhöhtes Risiko einer akzidentellen Kohlenmonoxidvergiftung. Die Anwendung von Desfluran mit hohem Frischgasfluß muß unter ökonomischen und ökologischen Aspekten kritisch betrachtet werden, so daß die routinemäßige Anwendung dieses Anästhetikums nur bei konsequenter Durchführung von Niedrigflußnarkosen zu empfehlen ist. Due to its low solubility and negligible metabolism, desflurane is assumed to be especially suitable for application by low-flow anaesthetic techniques. The aim of this clinical investigation was the development of a standardised dosing scheme for low-flow and minimal-flow desflurane anaesthesia. One hundred six ASA status I–II patients were assigned to six groups according to the duration of the initial high-flow phase, fresh gas flow, and fresh-gas desflurane concentration. The median age, height, body weight, and constitution of the groups was comparable. After an initial high-flow phase using 4.4 l/min, the fresh gas flow was reduced to 0.5 l/min (minimal-flow anaesthesia) or 1.0 l/min (low-flow anaesthesia). Inspired nitrous oxide concentrations were maintained at 60% to 70%. Using different standardised schemes of vaporizer settings, inspired desflurane concentrations were applied in the range from 3.4% to 8.7%, i.e., between 1 and 1.5 MAC. Inspired and expired desflurane concentrations were measured continuously by the side-stream technique and recorded on-line. Venous blood samples were taken immediately prior to induction and 45 min after flow reduction for measurement of carboxyhaemoglobin (COHb) concentration). In the 10- to 15-min initial phase during which a high fresh gas flow of 4.4 l/min was used, the inspired desflurane concentration reached values in the range of 90%–95% of the fresh gas concentration. In low-flow anaesthesia this concentration could be maintained without any alteration of the vaporizer setting, whereas in minimal-flow anaesthesia with flow reduction the fresh gas concentration had to be increased by 1% to 2%:The quotient calculated by division of the inspired desflurane concentration by its fresh gas concentration (Q=CI/CF) ranges between 0.65 and 0.75 in minimal-flow and between 0.80 and 0.85 in low-flow anaesthesia. If use was made of the wide output range of the desflurane vaporizer, the inspired concentration could be increased rapidly by about 5% in 8 min, although the flow was kept constant at 0.5 l/min. Compared with its value prior to induction (2.13±1.05%), the COHb concentration decreased statistically significantly by about 0.7% during the 1 st hour of minimal-flow anaesthesia (1.42±1.01%). In no case was a COHb concentration observed that exceeded threatening or even toxic values, although the soda lime was changed routinely only once a week. The pharmacokinetic properties of desflurane, resulting in especially low individual uptake, and the wide output range of the vaporizer facilitate the use of low-flow anaesthetic techniques in routine clinical practice. Even in minimal-flow anaesthesia, the duration of the initial high-flow phase can be shortened to min. If the flow is reduced to 1 l/min, the inspired desflurane concentration achieved in the initial high-flow phase can be maintained without any alteration of the vaporizer setting. In minimal-flow anaesthesia, however, with flow reduction to 0.5 l/min, the fresh gas concentration has to be increased to a value 1%–2% higher than the inspired nominal value. Due to the wide dialling range of the desflurane vaporizer, the amount of vapour delivered into the breathing system can be increased to about 110 ml/min even at a flow of 0.5 l/min. The large amount of agent that can be delivered into the system even under low-flow conditions, together with the very low individual uptake, results in a time-constant that is sufficiently short for the clinically required rapid increase in inspired desflurane concentrations. The short time-constant of low-flow desflurane anaesthesia improves the control of the anaesthetic concentration. If all measures are taken to safely avoid inadvertent drying out of the soda lime, there is no evidence that low-flow anaesthesia with desflurane is liable to increase the risk of accidental carbon monoxide poisoning. As the use of desflurane with high-flow anaesthetic techniques becomes wasteful, its routine clinical use from an economic and ecologic standpoint will only be justified if consistently applied with low-flow or minimal-flow anaesthesia.