Advances in continuously profiling the thermodynamic state of the boundary layer: integration of measurements and methods

This paper describes advances in ground-based thermodynamic profiling of the lower troposphere through sensor synergy. The well-documented integrated profiling technique (IPT), which uses a microwave profiler, a cloud radar, and a ceilometer to simultaneously retrieve vertical profiles of temperature, humidity, and liquid water content (LWC) of nonprecipitating clouds, is further developed toward an enhanced performance in the boundary layer and lower troposphere. For a more accurate temperature profile, this is accomplished by including an elevation scanning measurement modus of the microwave profiler. Height-dependent RMS accuracies of temperature (humidity) ranging from 0.3 to 0.9 K (0.5–0.8 g m−3) in the boundary layer are derived from retrieval simulations and confirmed experimentally with measurements at distinct heights taken during the 2005 International Lindenberg Campaign for Assessment of Humidity and Cloud Profiling Systems and its Impact on High-Resolution Modeling (LAUNCH) of the German Weather Service. Temperature inversions, especially of the lower boundary layer, are captured in a very satisfactory way by using the elevation scanning mode. To improve the quality of liquid water content measurements in clouds the authors incorporate a sophisticated target classification scheme developed within the European cloud observing network CloudNet. It allows the detailed discrimination between different types of backscatterers detected by cloud radar and ceilometer. Finally, to allow IPT application also to drizzling cases, an LWC profiling method is integrated. This technique classifies the detected hydrometeors into three different size classes using certain thresholds determined by radar reflectivity and/or ceilometer extinction profiles. By inclusion into IPT, the retrieved profiles are made consistent with the measurements of the microwave profiler and an LWC a priori profile. Results of IPT application to 13 days of the LAUNCH campaign are analyzed, and the importance of integrated profiling for model evaluation is underlined.

Stress field control of eruption dynamics at a rift volcano: Nyamuragira, D.R.Congo

Using the record of 30 flank eruptions over the last 110 years at Nyamuragira, we have tested the relationship between the eruption dynamics and the local stress field. There are two groups of eruptions based on their duration (< 80days >) that are also clustered in space and time. We find that the eruptions fed by dykes parallel to the East African Rift Valley have longer durations (and larger volumes) than those eruptions fed by dykes with other orientations. This is compatible with a model for compressible magma transported through an elastic-walled dyke in a differential stress field from an over-pressured reservoir (Woods et al., 2006). The observed pattern of eruptive fissures is consistent with a local stress field modified by a northwest-trending, right lateral slip fault that is part of the northern transfer zone of the Kivu Basin rift segment. We have also re-tested with new data the stochastic eruption models for Nyamuragira of Burt et al. (1994). The time-predictable, pressure-threshold model remains the best fit and is consistent with the typically observed declining rate of sulphur dioxide emission during the first few days of eruption with lava emission from a depressurising, closed, crustal reservoir. The 2.4-fold increase in long-term eruption rate that occurred after 1977 is confirmed in the new analysis. Since that change, the record has been dominated by short-duration eruptions fed by dykes perpendicular to the Rift. We suggest that the intrusion of a major dyke during the 1977 volcano-tectonic event at neighbouring Nyiragongo volcano inhibited subsequent dyke formation on the southern flanks of Nyamuragira and this may also have resulted in more dykes reaching the surface elsewhere. Thus that sudden change in output was a result of a changed stress field that forced more of the deep magma supply to the surface. Another volcano-tectonic event in 2002 may also have changed the magma output rate at Nyamuragira.

Predicting the annual performance of UK real estate: timeliness versus coverage

The IPD Annual Index is the largest and most comprehensive Real Estate market index available in the UK Such coverage however inevitably leads to delays in publication. In contrast there are a number of quarterly and monthly indices which are published within days of the year end but which lack the coverage in terms of size and numbers of properties. This paper analyses these smaller but more timely indices to see whether such indices can be used to predict the performance of the IPD Annual Index. Using a number of measures of forecasting accuracy it is shown that the smaller indices provide unbiased and efficient predictions of the IPD Annual Index. Such indices also significantly outperform a naive no-change model. Although no one index performs significantly better than the others. The more timely indices however do not perfectly track the IPD Annual Index. As a result any short run predictions of performance will be subject to a degree of error. Nevertheless the more timely indices, although lacking authoritative coverage, provide a valuable service to investors giving good estimates of Real Estates performance well before the publication of the IPD Annual Index.

Effect on components of the intestinal microflora and plasma neuropeptide levels of feeding Lactobacillus delbrueckii, Bifidobacterium lactis, and inulin to adult and elderly rats

The aim of this study was to compare the effects of the mixture of Lactobacillus delbrueckii subsp. rhamnosus strain GG, Bifidobacterium lactis Bb12, and inulin on intestinal populations of lactobacilli, bifidobacteria, and enterobacteria in adult and elderly rats fed the same (in quality and quantity) diet. The portal plasma levels of two neuropeptides, neuropeptide Y (NPY) and peptide YY (PYY), were also evaluated to assess the physiological consequences of the synbiotic treatment for the gastrointestinal (GI) tracts of rats of different ages. Adult (n = 24) and elderly (n = 24) male rats were fed the AIN-93 M maintenance diet. After 2 weeks of adaptation, the diet of 12 rats of each age group was supplemented with 8% inulin and with strains GG and Bb12 to provide 2.2 x 10(9) CFU of each strain g(-1) of the diet. Blood and different regions of the GI tract were sampled from all rats after 21 days of the treatment. Treatment with the mixture of strain GG, strain BB12, and inulin induced significantly different changes in the numbers of lactobacilli, bifidobacteria, and enterobacteria of the stomach, small intestine, cecum, and colon microflora. Moreover, the GG, BB12, and inulin mixture increased the concentrations of NPY and PYY for adult rats. For the elderly animals, the PYY concentration was not changed, while the NPY concentration was decreased by treatment with the GG, BB12, and inulin mixture. The results of the present study indicate that the physiological status of the GI tract, and not just diet, has a major role in the regulation of important groups of the GI bacteria community, since even the outcome of the dietary modification with synbiotics depends on the ages of the animals.

Effects of modified atmosphere packaging on quality of ‘Alphonso’ Mangoes

Postharvest quality of Alphonso mangoes (Mangifera indica L) is vital to ensure proper ripening and good quality. 500 g mature green mangoes, were subjected to three pre- packaging hot water dips (20, 30 & 40°C) for 40 min, two packaging films (OPP unperforated and perforated), using three levels of gas concentrations of 25,50 and 75% v/v CO2 treatments (balance N2) and stored at 10°C for 21 days. During the storage period headspace gas composition, weight loss, ascorbic acid, pulp firmness, external fruit colour and overall quality score were measured to determine optimum storage conditions. The most effective postharvest condition was found to be dipping in water maintained at 40°C for 40 min, followed by packaging under 50% CO2 in bags made of unperforated film when compared to mangoes packed under 25 and 75% CO2 which showed deteriorated quality including spoilage and mould. Good keeping quality of at least 21 days was achieved under these conditions, which was much superior to the control samples that showed deterioration after 12 days of storage.

Effects of dietary selenium supplementation on tissue selenium distribution and glutathione peroxidase activity in Chinese Ring Necked Pheasants

The objective of this study was to determine the concentration of total selenium (Se) and the proportions of total Se comprised as selenomethionine (SeMet) and selenocysteine (SeCys) in the post mortem tissues of female pheasants (Phasianus Colchicus Torquator) offered diets containing graded additions of selenized enriched yeast (SY) or sodium selenite (SS). Thiobarbituric acid reactive substances (TBARS) and tissue glutathione peroxidase (GSH-Px) activity of breast (Pectoralis Major) were assessed at 0 and 5 d post-mortem. A total of 216 female pheasant chicks were enrolled onto the study. 24 birds were euthanased at the start of the study and samples of blood, breast muscle, leg muscle (Peroneus Longus and M. Gastrocnemius), heart, liver, kidney and gizzard collected for determination of total Se. Remaining birds were blocked by live weight and randomly allocated to one of four dietary treatments (n=48 birds/treatment) that either differed in Se source (SY vs. SS) or dose (Con [0.2 mg total Se/kg], SY-L and SS-L [0.3 mg/kg total Se as SY and SS, respectively], and SY-H [0.45 mg total Se/kg]). Following 42 and 91 days of treatment 24 birds/treatment were euthanased and samples of blood, breast muscle, leg muscle, heart, liver, kidney and gizzard retained for determination of total Se and the proportion of total Se comprised as SeMet or SeCys. Whole blood GSH-Px activity was determined at each time point. Tissue GSH-Px activity and TBARS were determined in breast tissue at the end of the study. There were positive responses (P<0.001) in both blood and tissues to the graded addition of SY to the diet but the same responses were not apparent in the blood and tissues of selenite supplemented birds receiving comparable doses. Although there were differences between tissue types in the distribution of SeMet and SeCys there were few differences between treatments. There were effects of treatment on erythrocyte GSH-Px activity (P = 0.012) with values being higher in treatments SY-H and SS-L when compared to the negative control and treatment SY-L. There were no effects of treatment on tissue GSH-Px activity which is reflected in the overall lack of any treatment effects on TBARS.

Infection of gnotobiotic calves with Escherichia coli O157 : H7 strain A84

Six colostrum-deprived, hysterotomy-derived calves were maintained under sterile conditions and fed a milk replacer diet. At five days of age, five of the calves were dosed orally with 10(9)cfu of Escherichia coli O157: H7 strain A84. They were killed after, one, two, six, 12 and 24 days, and samples were taken for bacteriological and pathological examination. The sixth uninfected control calf was killed at seven days of age and matched samples were taken for pathological comparison. The animals remained normal throughout the observation period. Bacteriological data indicated a heavy bacterial load of strain A84 throughout the gastrointestinal tract but the bacterium was not found in liver, kidney or muscle. No evidence of attaching and effacing' lesions in the small or large intestine was found although there was a mild inflammatory response in the intestinal tract, consisting mainly of infiltrating eosinophils.

Growth of Salmonella enteritidis in artificially contaminated eggs: the effects of inoculum size and suspending media

Growth profiles of two isolates of Salmonella enteritidis phage type (PT) 4 inoculated into either the albumen of whole shell eggs or into separated albumen were found to be markedly affected by the size of the inoculum and the composition of the medium used to suspend the cells prior to inoculation. Using our model with an inoculum of two cells, multiplication of the Salmonella was not seen in 93% of eggs held at 20 degreesC for 8 days. In approximately 7% of eggs, however, growth occurred during the 8 days of storage. If the inoculum equaled or exceeded 25 cells per egg when eggs were subsequently stored at 20 degreesC, or 250 cells per egg when eggs were stored at 30 degreesC, high levels of growth of Salmonella in the egg occurred significantly more frequently than when the inoculum was two cells. High levels of growth were also seen more frequently if the inoculum was suspended in buffered peptone water or maximal recovery diluent rather than in phosphate buffered saline. Growth of Salmonella in separated albumen occurred very infrequently (1.1% of samples) at low inoculum levels and did not become significant until the inoculum was 250 cells or greater. Growth in the albumen was unaffected by the composition of the suspending medium. Provided that the inoculum was approximately 2 cells per egg and the bacteria were suspended in PBS, observed growth profiles of S. enteritidis inoculated into the albumen of whole eggs resembled those in naturally contaminated eggs. (C) 2001 Elsevier Science B.V. All rights reserved.

Lack of flagella disadvantages Salmonella enterica serovar Enteritidis during the early stages of infection in the rat

The roles of flagella and five fimbriae (SEF14, SEF17, SEF21, pef, lpf) in the early stages (up to 3 days) of Salmonella enterica serovar Enteritidis (S. Enteritidis) infection have been investigated in the rat. Wild-type strains LA5 and S1400 (fim+/fla+) and insertionally inactivated mutants unable to express the five fimbriae (fim-/fla+), flagella (fim+/fla-) or fimbriae and flagella (fim-/fla-) were used. All wild-type and mutant strains were able to colonize the gut and spread to the mesenteric lymph nodes, liver and spleen. There appeared to be little or no difference between the fim-/fla+ and wild-type (fim+/fla+) strains. In contrast, the numbers of aflagellate (fim+/fla- or fim-/fla-) salmonella in the liver and spleen were transiently reduced. In addition, fim+/fla- or fim-/fla-strains were less able to persist in the upper gastrointestinal tract and the inflammatory responses they elicited in the gut were less severe. Thus, expression of SEF14, SEF17, SEF21, pef and lpf did not appear to be a prerequisite for induction of S. Enteritidis infection in the rat. Deletion of flagella did, however, disadvantage the bacterium. This may be due to the inability to produce or release the potent immunomodulating protein flagellin.

Microbiological, chemical and rheological properties of low fat set yoghurt produced with exopolysaccharide (EPS) producing Bifidobacterium strains.

In this work, the microbiological and physicochemical differences of three types of low fat set yoghurts were studied, as well as the changes taking place during storage at 4 °C for 28 days. The first yoghurt was produced with yoghurt starters and exopolysaccharide (EPS) producing Bifidobacterium longum subsp. infantis CCUG 52486 (CCUGY), the second with yoghurt starters and Bifidobacterium infantis NCIMB 702205 (NCIMBY) and the third with just yoghurt starters (control yoghurt). No significant differences were observed in terms of cell concentrations; for all three yoghurts, similar final cell concentrations were obtained for the yoghurt starter cultures (~7.5 log cfu g−1) and the Bifidobacterium strains (~7.8 log cfu g−1). Both Bifidobacterium survived well during storage, as in both cases the cell viability decreased by less than 0.5 log cfu g−1after 28 days of storage. A decrease in pH followed by an increase in lactic acid was observed during storage for all three yoghurts, which was mostly attributed to the activity of the yoghurt starter cultures. The two yoghurts with the EPS producing Bifidobacterium strains exhibited lower syneresis than the control yoghurt. The lowest was shown by CCUGY, which also exhibited the highest storage modulus and firmness, and a well defined porous web-like structure in cryo-SEM. Examination of the micro-structure of the yoghurts using cryo-scanning electron microscopy (cryo-SEM) indicated that the above observations were due to the interaction between the EPS and the milk proteins. Overall, the results indicated that the EPS producing Bifidobacterium longum subsp. infantis CCUG 52486 is the most promising strain, and can be used with yoghurt starter cultures to manufacture low fat set yoghurt with probiotic activities and at the same time enhanced physicochemical and rheological properties.

Use of high-resolution NWP rainfall and river flow forecasts for advance warning of the Carlisle flood, north-west England

On the 8 January 2005 the city of Carlisle in north-west England was severely flooded following 2 days of almost continuous rain over the nearby hills. Orographic enhancement of the rain through the seeder–feeder mechanism led to the very high rainfall totals. This paper shows the impact of running the Met Office Unified Model (UM) with a grid spacing of 4 and 1 km compared to the 12 km available at the time of the event. These forecasts, and forecasts from the Nimrod nowcasting system, were fed into the Probability Distributed Model (PDM) to predict river flow at the outlets of two catchments important for flood warning. The results show the benefit of increased resolution in the UM, the benefit of coupling the high-resolution rainfall forecasts to the PDM and the improvement in timeliness of flood warning that might have been possible. Copyright © 2008 Royal Meteorological Society

Effects of soil conditions and drought on egg hatching and larval survival of the clover root weevil (Sitona lepidus)

Soil-dwelling insect herbivores are significant pests in many managed ecosystems. Because eggs and larvae are difficult to observe, mathematical models have been developed to predict life-cycle events occurring in the soil. To date, these models have incorporated very little empirical information about how soil and drought conditions interact to shape these processes. This study investigated how soil temperature (10, 15, 20 and 25 °C), water content (0.02 (air dried), 0.10 and 0.25 g g−1) and pH (5, 7 and 9) interactively affected egg hatching and early larval lifespan of the clover root weevil (Sitona lepidus Gyllenhal, Coleoptera: Curculionidae). Eggs developed over 3.5 times faster at 25 °C compared with 10 °C (hatching after 40.1 and 11.5 days, respectively). The effect of drought on S. lepidus eggs was investigated by exposing eggs to drought conditions before wetting the soil (2–12 days later) at four temperatures. No eggs hatched in dry soil, suggesting that S. lepidus eggs require water to remain viable. Eggs hatched significantly sooner in slightly acidic soil (pH 5) compared with soils with higher pH values. There was also a significant interaction between soil temperature, pH and soil water content. Egg viability was significantly reduced by exposure to drought. When exposed to 2–6 days of drought, egg viability was 80–100% at all temperatures but fell to 50% after 12 days exposure at 10 °C and did not hatch at all at 20 °C and above. Drought exposure also increased hatching time of viable eggs. The effects of soil conditions on unfed larvae were less influential, except for soil temperature which significantly reduced larval longevity by 57% when reared at 25 °C compared with 10 °C (4.1 and 9.7 days, respectively). The effects of soil conditions on S. lepidus eggs and larvae are discussed in the context of global climate change and how such empirically based information could be useful for refining existing mathematical models of these processes.

Establishment of normal gut microbiota is compromised under excessive hygiene conditions

Background: Early gut colonization events are purported to have a major impact on the incidence of infectious, inflammatory and autoimmune diseases in later life. Hence, factors which influence this process may have important implications for both human and animal health. Previously, we demonstrated strong influences of early-life environment on gut microbiota composition in adult pigs. Here, we sought to further investigate the impact of limiting microbial exposure during early life on the development of the pig gut microbiota. Methodology/Principal Findings: Outdoor- and indoor-reared animals, exposed to the microbiota in their natural rearing environment for the first two days of life, were transferred to an isolator facility and adult gut microbial diversity was analyzed by 16S rRNA gene sequencing. From a total of 2,196 high-quality 16S rRNA gene sequences, 440 phylotypes were identified in the outdoor group and 431 phylotypes in the indoor group. The majority of clones were assigned to the four phyla Firmicutes (67.5% of all sequences), Proteobacteria (17.7%), Bacteroidetes (13.5%) and to a lesser extent, Actinobacteria (0.1%). Although the initial maternal and environmental microbial inoculum of isolator-reared animals was identical to that of their naturally-reared littermates, the microbial succession and stabilization events reported previously in naturally-reared outdoor animals did not occur. In contrast, the gut microbiota of isolator-reared animals remained highly diverse containing a large number of distinct phylotypes. Conclusions/Significance: The results documented here indicate that establishment and development of the normal gut microbiota requires continuous microbial exposure during the early stages of life and this process is compromised under conditions of excessive hygiene.

Sources and spread of thermophilic Campylobacter spp. during partial depopulation of broiler chicken flocks

The practice of partial depopulation or ‘thinning’, i.e. early removal of a proportion of birds from a commercial broiler flock, is a reported risk factor for Campylobacter colonization of residual birds because of the difficulty in maintaining biosecurity during the process. Therefore, the effect of this practice was studied in detail for 51 target flocks, each at a different growing farm belonging to one of seven major poultry companies throughout the United Kingdom. On 21 of these farms, the target flock was already colonized by Campylobacter and at slaughter all cecal samples examined were positive, with a mean of log10 8 cfu / g. A further 27 flocks became positive within 2 – 6 days of the start of thinning and had similarly high levels of cecal carriage at slaughter. Just prior to the thinning process, Campylobacter could be isolated frequently from the farm driveways, transport vehicles, equipment and personnel. Strains from seven such farms on which flocks became colonized after thinning were examined by PFGE typing. The study demonstrated an association between strains occurring at specific sampling sites and those isolated subsequently from the thinned flocks. There were also indications that particular strains had spread from one farm to another, when the farms were jointly company-owned and served by the same bird-catching teams and / or vehicles. The results highlighted the need for better hygiene control in relation to catching equipment and personnel, and more effective cleaning and disinfection of vehicles, and bird-transport crates.

The influence of vegetation and building morphology on shadow patterns and mean radiant temperatures in urban areas: model development and evaluation

The solar and longwave environmental irradiance geometry (SOLWEIG) model simulates spatial variations of 3-D radiation fluxes and mean radiant temperature (T mrt) as well as shadow patterns in complex urban settings. In this paper, a new vegetation scheme is included in SOLWEIG and evaluated. The new shadow casting algorithm for complex vegetation structures makes it possible to obtain continuous images of shadow patterns and sky view factors taking both buildings and vegetation into account. For the calculation of 3-D radiation fluxes and T mrt, SOLWEIG only requires a limited number of inputs, such as global shortwave radiation, air temperature, relative humidity, geographical information (latitude, longitude and elevation) and urban geometry represented by high-resolution ground and building digital elevation models (DEM). Trees and bushes are represented by separate DEMs. The model is evaluated using 5 days of integral radiation measurements at two sites within a square surrounded by low-rise buildings and vegetation in Göteborg, Sweden (57°N). There is good agreement between modelled and observed values of T mrt, with an overall correspondence of R 2 = 0.91 (p < 0.01, RMSE = 3.1 K). A small overestimation of T mrt is found at locations shadowed by vegetation. Given this good performance a number of suggestions for future development are identified for applications which include for human comfort, building design, planning and evaluation of instrument exposure.