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Predicting the sensitivity of reef-building corals to disturbance, including bleaching, requires an understanding of physiological responses to stressors, which may be limited by destructive sampling and the capacity of common methodologies to characterize early life history stages. We developed a new methodology using laser scanning confocal microscopy (LSCM) to measure and track the physiological condition of corals. In a thermal stress experiment, we used LSCM to track coral condition during bleaching in adults and juveniles of two species, Montipora capitata and Pocillopora acuta. Depth of fluorescence in coral tissues provides a proxy measure of tissue thickness while Symbiodiniaceae population fluorescence relates to both population density and chlorophyll-α content. In response to thermal stress, there were significant shifts in tissue thickness and Symbiodiniaceae fluorescence with differences between life stages. This method is particularly well-suited for detecting shifts in physiological condition of living corals in laboratory studies, especially in small juvenile colonies.

The interfacial tension is a key quantity to phase and interphase behaviour of reservoir systems. Real systems consist of complex mixtures that are not easily accessible to theoretical considerations. By help of experimental analysis, main factors of influence can be determined that may be used for developing theoretical models and thus for obtaining deeper insight into dominating mechanisms. This work focuses on the role of carbon dioxide in gas and liquid mixtures comprising also hydrocarbons such as methane, n-pentane and n-heptane by determining the interfacial tension as a function of pressure in the range of 0.1–17 MPa at 313 and 323 K, gas composition and time. In the investigated systems, carbon dioxide shows to have a dominating effect caused by its high ability of dissolving in organic liquids and resulting in a strongly decreasing interfacial tension at elevated pressures. A further question addressed in the present work is in which way a changing concentration profile during mass transfer within a pendant drop is associated to the evolution of the interfacial tension. In binary systems, carbon dioxide is known to accumulate at the interface which happens immediately at its formation and covering any other dynamic effect. In ternary vapour–liquid–liquid systems that include water, mass transfer is shown to correlate with the time dependant interfacial tension.

The present work is focused on heat and mass transfer during drying of instant coffee within a vacuum belt dryer. A series of drying experiments in a lab-scale dryer were performed. Using an advanced temperature measurement technique, the process could be optimized with respect to product quality. Thermal conductivity of coffee extract was investigated over the whole range from liquid extract to dry product. Additionally, the influence of porosity was analyzed. Based on the results, a numeric model was developed describing the coupled heat and mass transfer. The understanding of the process has been improved and the basis for a strong optimization tool has been found.

The paper aims to the prediction of interfacial properties of binary mixtures using only pure component interfacial properties and bulk-properties of the mixture, like phase equilibria. This approach follows strictly the basic idea from Van der Waals. In principle, this goal can be reached by the application of the density gradient theory in combination with an equation of state. This paper focuses on the thermodynamic description of the phase and the surface properties for binary systems, if a supercritical component, like nitrogen or carbon dioxide (CO 2 ), is present in the mixture. Whereas nitrogen can be treated as non-polar component, carbon dioxide has a strong quadrupole moment. Using PCP-SAFT-EOS in combination with the density gradient theory the prediction of the surface tensions of mixtures close to experimental data is possible.

The density gradient theory was combined with a modern equation of state based on statistical mechanics, the perturbed chain-statistical association fluid theory, or with the well-known Peng−Robinson equation of state, and is applied to compute the surface tension of various binary mixtures made up of nonpolar substances. Additionally, some new data for the system methane + hexane and methane + heptane were measured using the pendant drop method equipped with a high-pressure cell. Both equations of state can be used to predict the surface tension of mixtures very close to experimental data. The surface tension of pure ethane could also be predicted using the surface tension data of other n-alkanes. Additionally, the surface tensions for mixtures as a function of liquid composition, of temperature, and of pressure were calculated for systems, where no experimental data are available. If the mixture contains a high volatile component, strong relative enrichment effects in the interface could be observed.

Human lymphocytes were exposed to the leukemogenic pesticide isofenphos (IFP) to investigate its effects on chromosomal DNA and cholinergic homeostasis using cholinesterase activity as a marker. Isolated peripheral lymphocytes were administered concentrations of IFP ranging from 0.1 ng/ml to 10 microg/ml. The absence (Group 1) and presence (Group 2) of DNA repair inhibitors 4 mM hydroxyurea (HU), 40 microM cytosine arabinoside (ARA-C) and an NADPH regenerating system (NRS) (Group 3) were analyzed at 1, 6 and 24 h by single cell gel electrophoresis using the comet assay. Significant damage to DNA directly from IFP at 1 h by remarkably low concentrations was observed in Group 1, escalating in Group 2 with DNA repair inhibition, while Group 3 disruptions were highest due to the presence of the NRS P-450 microsomal fraction conducive to producing reactive IFP-oxon and N-desalkyl metabolites. The extent of DNA aberrations increased further in parallel within the groups at 6 and 24 h. Male and female chemical sensitivities were similar on average (P < 0.01). Cholinesterase activity measured in a satellite group was inhibited with 0.1 microg/ml IFP by 69, 62, and 48% at 1, 6, and 24 h, respectively, indicating gradual induction of compensatory synthesis. Restoration of cholinergic homeostasis may be exceptionally impaired at higher IFP concentrations from acetyl-CoA depletion [Leuk. Res. 25 (2001) 883]. In summary, these studies reveal that exposure to the organophosphate pesticide isofenphos induces human DNA mutation beyond endogenous repair capacity and disrupts cholinergic nuclear signaling affectively constructing the mutator phenotype of leukemogenesis.

In the context of nucleation, bubble formation and their growth within polymer melts interfacial tension (IFT) plays an important role especially for understanding the complete foaming procedure and for taking influence on the resulting polymer foam characteristics. Material and system properties like the range of viscosity and IFT, mass transfer phenomena and chemical composition affect the choice of experimental methods for determining IFT. The PD technique has shown to be applicable to high experimental pressures and temperatures as well as relatively high liquid drop viscosity. In the presented investigation, different materials are applied in order to observe various effects that may take influence on the IFT of a polymer in condensed or supercritical fluid atmosphere. Liquid viscosity which varies with chain length and amount of dissolved gas does not take influence on the experimental result. The phase behaviour which also depends on molecular weight dominates the course of IFT at changing temperature and pressure. On the contrary to its monomer, complete mixing of polystyrene with compressed carbon dioxide is out of reach and IFT does not disappear within the investigated pressure range of up to 25 MPa. Based on a high number of experimental investigations, fluid mixtures are classified due to their mutual solubility in order to obtain qualitative information on IFT.

Fractionation of pigments occurs over time during supercritical extraction of oil from natural matrices containing carotenoids. Paprika powder and paprika oleoresin were extracted using CO2 at temperatures of up to 80°C and pressures up to 50 MPa. The pigment concentration in the supercritical phase was monitored with an on-line near infrared visible (NIR-VIS) detector. Concentrations of 90 to 200 g/kg total carotenoids were achieved in oleoresin extracted from starting material containing only 1.2 g/kg total carotenoids. The ratio of s-carotene + free xanthophylls to total carotenoids in the recovered oleoresin diminished from nearly 50% (w/w) at the beginning down to 10% at the end of the extraction. Increased pressure improved kinetics of carotenoid extraction.

Porosity and particle volume are important properties of solids in numerous technical processes. Dehydration in food technology often leads to a decrease of particle size, combined with a change of porosity. Knowledge of the moisture dependence of these properties helps to avoid quality losses during drying. Common methods of porosity determination like mercury porosimetry or B.E.T. gas adsorption do not allow moisture variation. Therefore, a porosity evaluation method consisting of a combination of image analysis and gas displacement in a pycnometer is developed. Taking helium as the gas allows to measure open as well as encapsulated pore volume of the biological product. With particular consideration of basic geometrical particle shape of the investigated natural bulk materials, the disadvantage of image analysis being a two-dimensional measuring method is limited. Experimental results are of high reproducibility and show good agreement with literature data and a standard porosimetry method. Particle size prediction derived from a combination of particle volume balance and estimated porosity shows good agreement between calculated and measured particle size, even under variation of moisture content. This comparison also indicates the high reliability of the presented porosity analysis.

The basic development of a contactless optionally density-independent and continuously operating on-line microwave moisture sensor for organic bulk materials is presented. Moisture determination by means of microwave power is volumetric, but for process control, quality preservation etc. the water content in weight percentage is recommended. Therefore, density and structure parameters, as well as dielectric properties, of different organic bulk materials with characteristic particle shape are measured and compared under different moisture content. Due to cellular tissues and organic compounds, structural behaviour depends very much on moisture and temperature. Results from compression experiments show the possibility of keeping the bulk structure constant within a wide range of water content. Consequently, microwave moisture measurement could be density-independent. A first calculation model shows the correlation between structure properties and the dielectric constant.

Neuronal intestinal dysplasia (NID) is wellknown, but its definition is a topic of debate. The histopathological diagnosis of NID is based on traditional enzyme-histochemical methods such as the acetylcholinesterase and dehydrogenase reaction on native cryosections. In this study, we have investigated the enteric nervous system in whole mount preparations of resected intestinal segments affected by NID of the plexus submucosus (type B). The plexuses of the tunica mucosa and tunica submucosa were visualized by immunohistochemical methods using a polyclonal antibody to protein gene produce 9.5 (PGP 9.5). PGP 9.5 is a novel general cytoplasmatic marker specific for the nervous system. The morphology of the plexuses is revealed in full, making possible changes easily discernible. Known pathological findings of the NID can be identified and judged more precisely with this method. Numerous enlarged nerve trunks run within the tunica submucosa and tunica mucosa. Hyperplastic ganglia with an unusually high nerve cell number in the tunica submucosa can be demonstrated as well as heterotopic nerve cells in the tunica mucosa.

Contents Catheters were surgically placed in the uterine artery and vein of four control and four dexamethasone (DXMS)-treated cows on days 248 or 249 of gestation; at the same time the corpus luteum was removed and all animals were treated with 10 mg chlormadinone acetate i.m. daily to maintain pregnancy. After one day of blood sampling which began on day 250, animals received either 20 mg DXMS crystalline suspension i.m. or only the vehicle solution. Blood sampling was then continued for five additional days. Plasma was assayed for unconjugated estrone (E1), progesterone (P4), and pregnenolone (P5). Concentrations of El were higher in the venous samples (p < 0.02) and increased over time (p < 0.02). There was a site x time interaction (p < 0.05) and a significant effect of DXMS-treatment on the linear component (p < 0.02) of the slope values for the El concentrations for both sampling sites. Concurrently, there was an effect of time on P4 concentrations (p lt; 0.01), the venous P4 concentrations were higher (p < 0.01), and there was also a site x time interaction (p < 0.01) but not treatment effect. There was no significant effect on concentrations of P5 between treatment goups or sampling sites. It is concluded that DXMS activates the synthetic system(s) involved in production of estrone in the cow during late pregnancy. This change in estrone synthesis occurred at an increasing rate during the 5 day sampling period. The data are consistent with the hypothesis that the placenta must be capable of utilizing precursors in the cholesterol or pregnenolone group for estrone synthesis and that the major pathway could be the delta-5 pathway. Inhalt: Veranderungen in der placentaren Hormonsekretion beim Rind nach Behandlung mit Dexamethason. Bei insgesamt 8 Kuhen wurden am 248./249. Tag der Trachtigkeit Katheter in die Vena und Arteria uterina eingelegt, gleichzeitig wurde das Corpus luteum entfernt und zur Aufrechterhaltung der Graviditat wurden 10 mg Chlormadinonacetat taglich wahrend der gesamten Versuchsdauer i.m. verabreicht. Nach einer ersten Blutentnahmeperiode am Tag 250 erhielten jeweils 4 Tiere entweder 20 mg Dexamethason (kristalline Suspension) bzw. das Vehikel (Kontrollguppe) i.m. verabreicht. Die Blutentnahmen erfolgten uber weitere 5 Tage, erfast wurde der Verlauf von freiem Estron, Progesteron und Pregnenolon. Die in der Vena uterina gemessenen Estronkonzentrationen lagen jeweils hoher (p < 0,02) als in der entsprechenden Arterie und stiegen bis zum Ende des Experiments an (p < 0,02). Weiterhin zeigte sich eine Interaktion zwischen dem Ort der Blutentnahme und dem Zeitpunkt (p < 0,05), der Anstieg der Estronkonzen-trationen nach der Behandlung mit Dexamethason war – bezogen auf die lineare Komponente – sigifikant erhoht (p < 0,02). Fur P4 ergab sich ein deutlicher Abfall (p < 0,01), wobei in der Vena uterina stets hohere Werte gemessen wurden als in der Arteria uterina (p < 0,01). Auch hier war eine Interaktion zwischen dem Zeitpunkt und dem Ort der Blutentnahme gegeben (p < 0,01), allerdings konnte ein Behandlungs-effekt nicht dargestellt werden. Fur Pregnenolon ergaben sich keine Unterschiede zwischen Arteria und Vena uterina sowie den Behandlungsgruppen. Die Ergebnisse zeigen, das eine einmalige Behandlung mit Dexamethason zu einer zunehmenden Steigerung der Estronproduktion fuhrt, im Hinblick auf die unveranderte Progesteronsekretion wird geschlossen, das dabei eher der Delta-5-Syntheseweg zugrundeliegen konnte und das die entsprechenden Precursoren auf der Ebene des Cholesterins oder Prepenolons zu suchen sind.

The kinetics of 13CO2 have been investigated following oral administration at five doses between 12.5 and 100 mg of 13C labelled sodium bicarbonate to 10 healthy subjects in a randomized study. Sodium bicarbonate in this study served as a model compound for carbon dioxide/bicarbonate generated in breath tests. Exhalation of 13CO2 into breath was monitored by stable isotope ratio mass spectrometry. The kinetics of 13CO2 were characterized by an apparent terminal elimination half-life of 1 h and a mean recovery of 0.630 of the dose administered. The kinetics were not dose-dependent. These results were in agreement with the findings reported previously after iv. application of sodium bicarbonate.

The emission of H and He isotopes in the reactions of 120 MeV 20 Ne with 27 A1 has been studied using light particle-heavy ion coincidence measurements. The energy spectra and angular correlations of the light particles emitted in coincidence with products of Z ≧ 14 agree well with the predictions of the statistical model applied to the decay of the compound nucleus 47 V. Results on α-particle emission associated with deep inelastic reactions leading to carbon and oxygen products are also reported.

Thiamine is important for oxidative metabolism, and B1 deficiency is thought to give rise to polyneuropathies. A group of male Wistar rats (n = 15) received a vitamin B1 deficient diet (group-a), and the pair fed control group (n = 20, group-b) received a normal diet with no vitamin deficiency. A second control group (group-c) was fed unrestrictedly with a standard diet (n = 19). All animals were examined for 25 weeks. The sensory nerve conduction velocity, the compound radicular, spinal and brain stem responses and the SEP were derived for tail and hind paw stimulation. The examination was repeated at 6-week intervals. There was no difference in nerve conduction between group-a and -b, but for both groups the conduction velocity was significantly slower than in group-c. The SEP latencies were significantly increased in group-a compared with group-b and also with group-c. The spinal and cerebral latencies were delayed in group-a. The diameters of myelinated nerve fibres were decreased in group-a compared with group-b, and in group-b compared with group-c. The results indicate that a specific polyneuropathy exists as a result of B1 deficiency, and that the sequelae of the lack of thiamine are pronounced in the CNS.

– Two groups of alcoholics (30 patients each) – identified by the MALT score – were examined. Clinical and laboratory investigations showed no connection between thiamine, riboflavin, or Vitamin B6 deficiency and development of the polyneuropathy. Neither the polyneuropathy nor the diminished sensory conduction velocity were related to malnutrition. The relation between the duration of alcoholism and symptoms of polyneuropathy was highly significant in one group. The neurotoxicity of ethanol was confirmed in an experiment with rats.

To determine the effect of short-term administration of diclofenac-colestyramine on glomerular filtration rate (GFR), renal plasma flow (RPF) and urinary excretion of prostanoids in patients with type-2 diabetes without and with impaired renal function.In the randomised, single-blind, placebo-controlled, two-period crossover study, 32 patients with type-2 diabetes (group 1: 16 patients without impaired renal function, creatinine clearanceor =80 ml/min and group 2: 16 patients with impaired renal function, creatinine clearance 30-79 ml/min) received 140 mg diclofenac-colestyramine (corresponding to 75 mg diclofenac sodium) or placebo twice a day on days 1 and 2 and once on day 3 with a wash-out period of 6 days between the two periods. GFR was assessed using both measurement of creatinine clearance and calculation of inulin clearance and RPF was assessed using calculation of para-aminohippurate (PAH) clearance after the short-term administration on day 3. Urinary excretion of prostanoids (PGE(2), PGE-M, 6-keto-PGF(1alpha), 2,3-dinor-6-keto-PGF(1alpha), TxB(2), 2,3-dinor-TxB(2) and 11-dehydro-TxB(2)) were measured before and after drug intake.Comparison with placebo showed no effect of diclofenac-colestyramine on creatinine, inulin or PAH clearance ( P0.05) in patients with type-2 diabetes either without or with impaired renal function. The differences in creatinine, inulin and PAH clearance between the two groups of patients were not influenced by diclofenac-colestyramine. Urinary excretion of PGE(2), PGE-M, 6-keto-PGF(1alpha), 2,3-dinor-6-keto-PGF(1alpha), TxB(2), 2,3-dinor-TxB(2) ( P=1.89) and 11-dehydro-TxB(2) was significantly reduced by diclofenac-colestyramine.These results indicate that proven non-specific cyclooxygenase inhibition by short-term administration of diclofenac-colestyramine did not affect renal haemodynamic function (GFR, RPF) in patients with type-2 diabetes either without or with impaired renal function.