bluuebunny/crossref_metadata_2025 huggingface dataset:
The 1998 debris avalanche at Casita volcano, Nicaragua: Investigation of the role of hydrothermal smectite in promoting slope instability
Authors: Opfergelt S. , Delmelle P. , Boivin P. , Delvaux B.
Published: August 2006

Buildup of excess pore water pressure within highly fractured rocks is held responsible for the initiation of the disastrous 1998 debris avalanche at Casita volcano, Nicaragua. Here, we postulate that the presence of smectite clay (up to 50 wt.%) in the hydrothermally‐altered bedrock contributed to slope instability. Over decades or more, the clayey material probably (i) acted as an efficient barrier to water infiltration, (ii) progressively decreased shear‐strength, and (iii) gradually destabilized the overlying rock mass. These effects are explained by the shrink‐swell behavior of the clay‐rich bedrock. During intense rainfall, formation of incipient weak failure surfaces in the superficial rock mass could have been favoured due to rapid alteration in the mechanical properties of smectite‐containing clays deposited in fracture, joint and gouge interfaces.
Small net carbon dioxide uptake by Russian forests during 1981–1999
Authors: Beer C. , Lucht W. , Schmullius C. , Shvidenko A.
Published: August 2006

A permafrost‐enhanced biogeochemical process model using observed climate and CO2 data, and satellite‐observed maps of forest composition and density predicts a moderate biomass increment and carbon sink of 74 and 131 Tg carbon per year (TgC/a) in the Russian forests during 1981–1999. The enhanced process model realistically represents ecosystem state in terms of river runoff, area burned by fires, vegetation productivity and biomass, in comparison to monitoring and inventory data. Rising atmospheric CO2 content is found to have been the main cause of the carbon sink. Amounting to 7% of carbon emissions from fossil fuel emissions in Eurasia, our results demonstrate a limited capability of the Russian boreal forest in its current state to compensate anthropogenic carbon emissions.
Kelvin‐Helmholtz instability in a magnetotail flank‐like geometry: Three‐dimensional MHD simulations
Authors: Takagi K. , Hashimoto C. , Hasegawa H. , Fujimoto M. , TanDokoro R.
Published: August 2006

Three‐dimensional MHD simulations of the Kelvin‐Helmholtz instability (KHI) have been performed to investigate its relevance to the magnetotail‐flank situation. The effect of the KH‐stable lobe region on its growth at the plasma sheet–magnetosheath interface can be a crucial factor. To assess this effect, we study how the KHI grows in an unstable layer of finite thickness (plasma sheet) sandwiched between stable regions (north and south lobes). The results show that when the magnetosheath magnetic field is northward, the instability grows vigorously to form a highly rolled‐up vortex even when the plasma sheet thickness is smaller than the wavelength of the fastest‐growing mode. Furthermore, two rolled‐up vortices can coalesce into a larger one as long as the thickness is larger than the wavelength. The coalescence under the tail‐flank geometry causes strong stretching of the field lines, leading to the condition under which reconnection could easily be triggered. These findings suggest that when the magnetosheath condition is favorable for the KHI and when the plasma sheet is thicker than a few RE, the vortices become an important element of the tail‐flank dynamics. We also found that in rolled‐up vortices, the tailward speed of the plasma sheet plasma exceeds that of the magnetosheath flow in regions where it penetrates toward the magnetosheath. Since this overshoot acceleration is seen only when the vortex is rolled up and is detectable even from single‐spacecraft observations, we suggest that it can be used as a marker of the roll‐up of vortices.
Differential secretion of lactate and activity of plasma membrane H+-ATPase in the roots of soybean seedlings in response to low-oxygen stress
Authors: Shen Hong , Jing Weibin , Ai Tiancheng , Lu Ying , Cheng Jianxun
Published: August 2006

Plants display a series of tolerance mechanism following exposure to low-oxygen stress. Increased secretion of end production of carbohydrate catabolism and synthesis of stress-related proteins are important mechanisms enabling the plant to develop tolerance to anoxia stress. In this study, the secretion of lactate and the activity of plasma membrane H+-ATPase in a wild-type (WTS) and a cultivated soybean (CTS) were investigated in response to low-oxygen stress. Low oxygen (0.1% O2, anoxia) increased the secretion of lactate and reduced the activity of plasma membrane H+-ATPase and ATP content in a time-dependent manner. WTS showed greater root elongation and higher survivability than CTS. The higher lactate secretion coincided with the lower accumulation of lactate in WTS than in CTS. Anoxia decreased the cellular pH in soybean roots. Hypoxia (5% O2) increased the secretion of lactate and the activity of plasma membrane H+-ATPase. In comparison to anoxia, hypoxia stress induced increases of 57.4 and 29.7% of endogenous abscisic acid (ABA) in the root apices of WTS and CTS, respectively. Exogenous application of ABA showed a stimulatory effect on the activity of plasma membrane H+-ATPase and the secretion of citrate from soybean roots. However, cycloheximide, an inhibitor of protein synthesis, abolished ABA effects. These results suggest that the modulation of the secretion of lactate and activity of plasma membrane H+-ATPase in soybean roots is associated with the mechanisms of tolerance to low-oxygen stress. ABA might be involved in the hypoxia signal transmitted in soybean roots.
The ecology and evolution of gender strategies in plants: the example of Australian Wurmbea (Colchicaceae)
Authors: Barrett Spencer C. H. , Case Andrea L.
Published: August 2006

Angiosperms possess diverse sexual systems, often with different combinations of hermaphroditic, pistillate and staminate flowers. Despite this sexual diversity, most populations are either monomorphic or dimorphic with respect to gender strategy, where gender refers to the relative contribution that individuals make to fitness through female and male function. An important problem in evolutionary biology is to determine how and why variation in gender strategies originates and is maintained. Wurmbea (Colchicaceae), a genus of insect-pollinated geophytes, has recently become the focus of ecological and evolutionary studies aimed at understanding these issues. Phylogenetic reconstructions suggest dispersal from Africa to Australia, then New Zealand, and multiple transitions between monomorphic and dimorphic sexual systems within Australia. Microevolutionary studies of W. dioica and W. biglandulosa, two wide-ranging taxa with monomorphic and dimorphic populations, provide insights into the selective mechanisms governing transitions between sexual systems. Dimorphic populations of these taxa likely comprise independent origins of dimorphism via the gynodioecious pathway by invasion of females into monomorphic populations. Shifts in pollination biology and flower size, and their consequent effects on mating patterns, may have contributed to the evolution of gender dimorphism. Pollinator-mediated selfing and inbreeding depression provide a sufficient fertility advantage for females to be maintained in dimorphic populations. Once dimorphism establishes, increasing gender specialisation is associated with invasion of more arid environments. Inbreeding avoidance, particularly under stressful ecological conditions, is the most likely selective mechanism maintaining gender dimorphism in Wurmbea. We conclude our review by suggesting avenues for future research that might provide a more comprehensive picture of the evolution of gender strategies in Wurmbea.
Evaporative cooling efficiency of a fogging system in a rose greenhouse
Authors: Ozturk H. H.
Published: August 2006

The objective of this study was to investigate the effect of a fogging system on the microclimate of a rose greenhouse. The experiments were carried out in a multi-span plastic greenhouse, 106 wide by 205 m long, made of 11 spans. The fogging system consisted of a water softener and filters to prevent nozzle clogging, a water reservoir, pumps and a pressure regulator, and fog generating nozzles. Three nozzle lines with 82 fog generating nozzles were installed in each span of the plastic greenhouse. At each nozzle line, 82 fog generating nozzles were uniformly located at 2.5 m nozzle spacing. The fog generating nozzle parameters were determined to characterise the efficiency of the fogging system based on air flow rate and evaporation flow rate. The results showed that the fogging system was able to keep the air temperature inside the plastic greenhouse 6.6°C lower than that outside. The average ventilation rate of the plastic greenhouse was 13.6 m3/s during the experimental period. The efficiency of the fogging system ranged from 11.7 to 80%. The efficiency of the fogging system increased as the difference between the dry-bulb temperature and wet-bulb temperature rose. The results indicated that air relative humidity inside the plastic greenhouse was increased by 25% on average by means of the fogging system examined in this study. The evaporation flow rate varied between 130 and 1223 g/h.m2, whereas the air flow rate ranged from 39.3 to 298 kg/h.m2. Fogging system efficiency increased linearly with evaporation flow rate and the absolute humidity difference between the inside and outside air.
Activation of heterotrimeric G proteins by Smoothened
Authors: Riobo Natalia A. , Saucy Berangere , DiLizio Cherisse , Manning David R.
Published: August 2006

The mechanisms by which the activation of Smoothened (Smo), a protein essential to the actions of the Hedgehog family of secreted proteins, is translated into signals that converge on the Gli transcription factors are not fully understood. The seven-transmembrane structure of Smo has long implied the utilization of heterotrimeric GTP-binding regulatory proteins (G proteins); however, evidence in this regard has been indirect and contradictory. In the current study we evaluated the capacity of mammalian Smo to couple to G proteins directly. We found that Smo, by virtue of what appears to be constitutive activity, activates all members of the G
i
family but does not activate members of the G
s
, G
q
, and G
12
families. The activation is suppressed by cyclopamine and other inhibitors of Hedgehog signaling and is enhanced by the Smo agonist purmorphamine. Activation of G
i
by Smo is essential in the activation of Gli in fibroblasts, because disruption of coupling to G
i
with pertussis toxin inhibits the activation of Gli by Sonic hedgehog and a constitutively active form of Smo (SmoM2). However, G
i
does not provide a sufficient signal because a truncated form of Smo, although capable of activating G
i
, does not effect activation of Gli. Rescue of pertussis toxin-inhibited activation of Gli by Sonic hedgehog can be achieved with a constitutively active Gα
i
-subunit. The data suggest that Smo is in fact the source of two signals relevant to the activation of Gli: one involving G
i
and the other involving events at Smo’s
C
-tail independent of G
i
.
NF-κB-dependent induction of microRNA miR-146, an inhibitor targeted to signaling proteins of innate immune responses
Authors: Taganov Konstantin D. , Boldin Mark P. , Chang Kuang-Jung , Baltimore David
Published: August 2006

Activation of mammalian innate and acquired immune responses must be tightly regulated by elaborate mechanisms to control their onset and termination. MicroRNAs have been implicated as negative regulators controlling diverse biological processes at the level of posttranscriptional repression. Expression profiling of 200 microRNAs in human monocytes revealed that several of them (miR-146a/b, miR-132, and miR-155) are endotoxin-responsive genes. Analysis of miR-146a and miR-146b gene expression unveiled a pattern of induction in response to a variety of microbial components and proinflammatory cytokines. By means of promoter analysis, miR-146a was found to be a NF-κB-dependent gene. Importantly, miR-146a/b were predicted to base-pair with sequences in the 3′ UTRs of the TNF receptor-associated factor 6 and IL-1 receptor-associated kinase 1 genes, and we found that these UTRs inhibit expression of a linked reporter gene. These genes encode two key adapter molecules downstream of Toll-like and cytokine receptors. Thus, we propose a role for miR-146 in control of Toll-like receptor and cytokine signaling through a negative feedback regulation loop involving down-regulation of IL-1 receptor-associated kinase 1 and TNF receptor-associated factor 6 protein levels.
Magnetic resonance imaging with an optical atomic magnetometer
Authors: Xu Shoujun , Yashchuk Valeriy V. , Donaldson Marcus H. , Rochester Simon M. , Budker Dmitry , Pines Alexander
Published: August 2006

We report an approach for the detection of magnetic resonance imaging without superconducting magnets and cryogenics: optical atomic magnetometry. This technique possesses a high sensitivity independent of the strength of the static magnetic field, extending the applicability of magnetic resonance imaging to low magnetic fields and eliminating imaging artifacts associated with high fields. By coupling with a remote-detection scheme, thereby improving the filling factor of the sample, we obtained time-resolved flow images of water with a temporal resolution of 0.1 s and spatial resolutions of 1.6 mm perpendicular to the flow and 4.5 mm along the flow. Potentially inexpensive, compact, and mobile, our technique provides a viable alternative for MRI detection with substantially enhanced sensitivity and time resolution for various situations where traditional MRI is not optimal.
Choice of grass or maize silages by lactating dairy cows: influence of supplementary protein, concentrate level and milk yield
Authors: Habib M. , Syed J.S. , Leaver J.D.
Published: August 2006

Abstrat

Preference testing of two foods provides a means of assessing the relative value an animal places on the foods. Two experiments examined the relative choice of grass and maize silages by lactating dairy cows, and investigated whether protein supplementation, concentrate level or milk yield level of cow influenced this choice. In experiment 1, 16 cows including eight high (30 kg/day) and eight low (17 kg/day) yielding (milk level, ML) cows were offered a low (171 g/kg dry matter (DM)) or a high (300 g/kg DM) crude protein (CP) concentrate in eight 2×2 Latin squares. In experiment 2, four cows were offered a low (112 g/kg DM) or a high (334 g/kg DM) CP content of concentrate at a low (3·5 kg/day) or high (7 kg/day) concentrate level (CL) in a 4×4 Latin-square design.CP of concentrate did not influence the proportion of grass silage to maize silage eaten in either experiment. Also, neither ML of cows (experiment 1) nor CL (experiment 2) affected proportions of the two silages eaten. The mean proportions selected were 0·88:0·12 and 0·52:0·48 for grass and maize silages in experiments 1 and 2 respectively, which reflected differences between experiments in the digestibilities of the silages, and indicated that digestibility may be an important factor influencing the choice of silages.The CP, CL and ML treatments produced significant responses in silage and total DM intakes. Feeding behaviour studies showed the responses to CP were associated with differences in meal size, which is a function of duration of each meal and rate of intake. The number of meals taken per day was similar for all treatments and averaged 8·0 and 8·1 for experiments 1 and 2 respectively.It was concluded that whilst lactating cows modified their feeding behaviour in response to the diets available, there was no evidence they modified the proportions of the two silages selected in order to meet a target protein content in the total diet. It would appear therefore that other factors, of which digestibility may be important, have a higher priority in choice.
Links between specialization in the finishing of bulls, mixing, farmers' attitudes towards animals and the production of finishing bulls: a survey on French farms
Authors: Mounier L. , Colson S. , Roux M. , Dubroeucq H. , Boissy A. , Ingrand S. , Veissier I.
Published: August 2006

In France, beef bulls are finished by breeder-finishers who produce calves and then fatten them, or by specialized finishers who fatten bulls that they buy. According to previous results on both dairy cows and pigs, breeding on the farm promotes positive attitudes of farmers towards animals, which can lead to improved animal health and growth. The mixing of bulls on their arrival at a specialized unit could stress them and thus impair health and growth. We hypothesized that breeder-finishers have more positive attitudes towards bulls and their work with bulls than specialized finishers, and that positive attitudes lead to better production, whereas mixing may be counterproductive. We observed 1038 bulls (67 groups) finished by breeder-finishers or specialized finishers in mixed and unmixed groups. Using a questionnaire, we assessed farmers' beliefs about the sensitivities of bulls, their attitude towards contacts with bulls, their beliefs about successful factors in finishing, and job satisfaction. We recorded the number of clinical signs and weight gain of the bulls. Specialized finishers tended to have more negative contacts with bulls than breeder-finishers (P=0·06). Poor health of bulls was associated with (i) a positive attitude towards gentle contacts with bulls (P<0·01), (ii) job satisfaction (P=0·01), and (iii) was negatively correlated to beliefs in bulls being difficult animals (P=0·09). Fast growth of bulls was associated with job satisfaction (P<0·01). Unmixed bulls grew faster than mixed bulls (P=0·05). We conclude that in finishing bulls, it is production results that have an impact on attitudes, rather than the opposite: the need for close contacts with bulls resulting from health problems engenders more positive attitudes of farmers towards their animals, and good production results increase job satisfaction. Variations in production results between breeder-finishers and specialized finishers seem to lie more in the fact that the latter always use animals mixed at the beginning of the finishing period - with mixing impairing growth - than in the attitudes of farmers towards animals and their work.
Interleukin-1ra increases growth performance and body protein accretion and decreases the cytokine response in a model of subclinical disease in growing pigs
Authors: Dionissopoulos L. , Dewey C.E. , Namkung H. , De Lange C.F.M.
Published: August 2006

There is a growing body of evidence to suggest direct involvement of the cytokines interleukin-1 (IL-1), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) in the initiation of skeletal muscle catabolism and depressions in growth performance as a result of diseases, while TNF-α and IL-6 are presumably under the control of IL-1. An experiment was conducted to investigate whether an interleukin-1 receptor antagonist (IL-1ra) could reduce growth depressions in a model of subclinical disease in growing pigs. In this study, 24 crossbred barrows and gilts were randomly assigned to three treatments: (1) healthy control (HC), saline infusion; (2) sick control (SC), infection withMycoplasma hyopneumoniaeand vaccination with porcine reproductive and respiratory syndrome modified live virus (PRRSV) vaccine and saline infusion; (3) SC plus infusion with IL-1ra (SC+IL-1ra). An additional six pigs were killed at the initiation of the trial to determine initial body composition for estimation of carcass nutrient retention rates. During the 28-day experimental period, the SC pigs had growth performance similar to that of the HC pigs and the highest levels of plasma cytokines (P<0·10). The SC+IL-1ra pigs had growth performance similar to the HC pigs, but the SC+Il-1ra pigs tended to have higher growth rates than the SC pigs (P<0·10), the highest carcass protein accretion rate (P<0·10) and similar levels of plasma cytokines compared with the HC pigs. Plasma levels of insulin-like growth factor-1 (IGF-1) on day 22 tended to be higher (P<0·10) in the HC pigs compared with the SC or SC+IL-1ra pigs and treatment×sex interaction was observed on day 29; the IGF-1 levels tended to be higher in SC+IL-1ra gilts and SC barrows (P<0·10). These results indicate that infusion with IL-1ra in a model of subclinical disease helps attenuate the catabolic effects of immune system stimulation.
Use of a partial least-squares regression model to predict test day of milk, fat and protein yields in dairy goats
Authors: Macciotta N.P.P. , Dimauro C. , Bacciu N. , Fresi P. , Cappio-Borlino A.
Published: August 2006

A model able to predict missing test day data for milk, fat and protein yields on the basis of few recorded tests was proposed, based on the partial least squares (PLS) regression technique, a multivariate method that is able to solve problems related to high collinearity among predictors. A data set of 1731 lactations of Sarda breed dairy Goats was split into two data sets, one for model estimation and the other for the evaluation of PLS prediction capability. Eight scenarios of simplified recording schemes for fat and protein yields were simulated. Correlations among predicted and observed test day yields were quite high (from 0·50 to 0·88 and from 0·53 to 0·96 for fat and protein yields, respectively, in the different scenarios). Results highlight great flexibility and accuracy of this multivariate technique.
Trends in milk production, calving rate and survival of cows in 14 Irish dairy herds as a result of the introgression of Holstein-Friesian genes
Authors: Evans R. D. , Dillon P. , Buckley F. , Berry D. P. , Wallace M. , Ducrocq V. , Garrick D. J.
Published: August 2006

Trends in milk production, calving rates, and survival were monitored on a potential 5580 primiparous and multiparous Holstein-Friesian dairy cows across 14 Irish seasonal spring-calving dairy farms between the years 1990 and 2001. Over this period calving rate to first service (CALV1) reduced by 0·96% per year (55 to 44%;P< 0·001), calving rate to first and second service (CALV12) reduced by 0·84% per year ( 77 to 70%;P< 0·001) and herd average parity number reduced by 0·10 lactation per year (4·3 to 3·5;P<0·001). The proportion of North American Holstein Friesian (NAHF) genes in the cows increased by 5·5% per year (8 to 63%;P<0·001), while pedigree index for milk yield (PIMILK) of the cows increased by 25 kg per year (P<0·001). The predicted difference of the sires of the cows for calving interval and survival increased by 0·5 days (P<0·001) and reduced by 0·12% (P<0·001) per year, respectively. A negative association was found between increased phenotypic milk yield, NAHF and PIMILKand reduced calving rates as assessed by CALV1 and CALV12. Increased proportion of NAHF genes exhibited a negative effect on survival (P<0·001) whereas increased levels of heterosis had a positive impact on survival (P<0·001). The results of the present study indicate that in seasonal calving herds in Ireland a need for direct selection on traits related to fertility and survival is required to arrest and reverse the declining trends in calving rates and survival.
The effect of strain of Holstein-Friesian dairy cow and pasture-based system on grass intake and milk production
Authors: Horan B. , Faverdin P. , Delaby L. , Rath M. , Dillon P.
Published: August 2006

The objective of this study was to investigate the effects of strain of Holstein-Friesian cow, pasture-based feeding system (FS) and their interaction on milk production, dry matter (DM) intake and energy balance over 3 years consecutively. The three strains were: high milk production North American (HP), high fertility and survival (durability) North American (HD) and New Zealand (NZ). The FS were: a high grass allowance (HG FS), a high concentrate (HC FS) and a high stocking rate (HS FS). A separate farmlet existed for each FS and a total of 99, 117 and 117 animals were used in year 1, year 2 and year 3, respectively, divided equally between strains and FS. Individual animal intakes were estimated three times each year at pasture; in May (P1), in July (P2) and October (P3), corresponding on average to day 102, 177 and 240 of lactation, respectively. The HP cows achieved the highest milk yield, the NZ the lowest, while the HD was intermediate; the HP achieved the highest solid corrected milk yield with no difference between the NZ and HD strains. The grass DM intake of the HP strain was highest ( P<0·001) in all feeding systems. There was a significant strain×FS interaction for yield of milk, fat and protein, grass DM and total DM intake. The milk production response to the HC FS in P1 and P2 was significantly greater for both the HP and HD strains than for the NZ strain, while in P3 the response was highest for the HP, lowest for the NZ and intermediate for the HD. The reduction in pasture DM intake per kg of concentrate was greatest for the NZ strain, lowest for the HP and intermediate for the HD strain. The NZ strain also had the highest grass DM intake per kg live weight. The existence of strain×FS interactions for production and DM intake indicate that greater knowledge of both genotype and feeding environment is required to predict animal performance.
Pro-inflammatory cytokine and acute phase protein responses to low-dose lipopolysaccharide (LPS) challenge in pigs
Authors: Llamas Moya S. , Boyle L. , Lynch P. B. , Arkins S.
Published: August 2006

The objective of this study was to establish the pro-inflammatory cytokine and acute phase protein responses to low-dose lipopolysaccharide (LPS) challenge in pigs and to determine whether these immune parameters could also be measured in saliva. Possible gender differences in the acute phase reaction were also assessed. At 6 weeks of age, 24 male and 24 female pigs were injected intraperitoneally with a single dose of 0 or 5 μg/kg live weight (LW) of LPS fromEscherichia coli(treatment). Matched saliva and blood samples were taken at 0, 2, 4, 8, 12 or 24 h after treatment administration. Samples were analysed for concentrations of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β), the acute phase proteins C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin (Hp), and cortisol. Low-dose LPS administration increased plasma levels of TNF-α (P<0·001), CRP (P<0·05) and SAA (P<0·05) but did not affect plasma concentrations of IL-1β or Hp (P>0·1). Treatment by time interactions showed that plasma levels of TNF-α and CRP in LPS-treated pigs peaked at 2 h (P<0·001) and 12 h (P<0·01), respectively. Low-dose LPS injection tended to increase plasma concentrations of cortisol (P=0·056) and the response to LPS differed between genders (P<0·05), with females showing higher cortisol responsiveness to the challenge (P<0·01). Males showed higher levels of both cytokines regardless of the treatment (P<0·05), probably due to the inhibition of cytokine synthesis by cortisol. Concentrations of both pro-inflammatory cytokines were consistently detectable in saliva and were present in higher concentrations than in plasma (P<0·001). Hence, plasma TNF-α, CRP and SAA are useful indicators of sub-acute inflammation/infection in pigs as simulated by a low-dose LPS challenge and gender differences exist in the pro-inflammatory cytokine response after a low dose of LPS.
Review Article: Public health policies: A Scandinavian model?
Authors: Vallgårda Signild
Published: August 2006

Aim: To identify how public health problems are identified, explained, and addressed in Scandinavian public health programmes. Methods: Recent public health white papers from Denmark, Norway, and Sweden have been studied asking the following questions. How are policies and activities justified? Which problems and causes are identified? What is to be done? To what extent are the interpretations and suggested interventions in accordance with liberal or social democratic political ideals? Results: The programmes studied give similar reasons for dealing with public health, namely the wish to create good lives for citizens and to improve the economy of society. The health problems identified are almost the same: cancer, heart disease, diabetes, musculoskeletal diseases, and mental illness. The Danish programme differs from its Norwegian and Swedish counterparts with regard to explanations and suggested solutions to the problems. It may be characterized as more liberal. While the Danish programme stresses the importance of individual behaviour, responsibility, and autonomy, the two others emphasize social relations, living conditions, and participation in addition to behavioural factors. Political responsibility for the health of the population is emphasized in the Norwegian and Swedish programmes. The Swedish programme, in particular, stresses common values such as equality and equal rights, and the significance of the welfare state. The Norwegian programme underlines the importance of empowering the individual, an ambition that could also be seen as a social liberal ambition to increase the self-determination of citizens. Conclusion: There is not one Scandinavian model in public health policy but several: a Danish model mainly adhering to liberal ideals, a Norwegian one that could tentatively be labelled social liberal, and a Swedish model adhering to more social democratic ideals.
Delineation of the Roles Played by RasG and RasC in cAMP-dependent Signal Transduction during the Early Development ofDictyostelium discoideum
Authors: Bolourani Parvin , Spiegelman George B. , Weeks Gerald
Published: August 2006

On starvation, the cellular slime mold Dictyostelium discoideum initiates a program of development leading to formation of multicellular structures. The initial cell aggregation requires chemotaxis to cyclic AMP (cAMP) and relay of the cAMP signal by the activation of adenylyl cyclase (ACA), and it has been shown previously that the Ras protein RasC is involved in both processes. Insertional inactivation of the rasG gene resulted in delayed aggregation and a partial inhibition of early gene expression, suggesting that RasG also has a role in early development. Both chemotaxis and ACA activation were reduced in the rasG−cells, but the effect on chemotaxis was more pronounced. When the responses of rasG−cells to cAMP were compared with the responses of rasC−and rasC−rasG−strains, generated in otherwise isogenic backgrounds, these studies revealed that signal transduction through RasG is more important in chemotaxis and early gene expression, but that signal transduction through RasC is more important in ACA activation. Because the loss of either of the two Ras proteins alone did not result in a total loss of signal output down either of the branches of the cAMP signal-response pathway, there appears to be some overlap of function.
A Functional Role for the GCC185 Golgin in Mannose 6-Phosphate Receptor Recycling
Authors: Reddy Jonathan V. , Burguete Alondra Schweizer , Sridevi Khambhampaty , Ganley Ian G. , Nottingham Ryan M. , Pfeffer Suzanne R.
Published: August 2006

Mannose 6-phosphate receptors (MPRs) deliver newly synthesized lysosomal enzymes to endosomes and then recycle to the Golgi. MPR recycling requires Rab9 GTPase; Rab9 recruits the cytosolic adaptor TIP47 and enhances its ability to bind to MPR cytoplasmic domains during transport vesicle formation. Rab9-bearing vesicles then fuse with the trans-Golgi network (TGN) in living cells, but nothing is known about how these vesicles identify and dock with their target. We show here that GCC185, a member of the Golgin family of putative tethering proteins, is a Rab9 effector that is required for MPR recycling from endosomes to the TGN in living cells, and in vitro. GCC185 does not rely on Rab9 for its TGN localization; depletion of GCC185 slightly alters the Golgi ribbon but does not interfere with Golgi function. Loss of GCC185 triggers enhanced degradation of mannose 6-phosphate receptors and enhanced secretion of hexosaminidase. These data assign a specific pathway to an interesting, TGN-localized protein and suggest that GCC185 may participate in the docking of late endosome-derived, Rab9-bearing transport vesicles at the TGN.
Shiga Toxin Facilitates Its Retrograde Transport by Modifying Microtubule Dynamics
Authors: Hehnly Heidi , Sheff David , Stamnes Mark
Published: August 2006

The bacterial exotoxin Shiga toxin is endocytosed by mammalian host cells and transported retrogradely through the secretory pathway before entering the cytosol. Shiga toxin also increases the levels of microfilaments and microtubules (MTs) upon binding to the cell surface. The purpose for this alteration in cytoskeletal dynamics is unknown. We have investigated whether Shiga toxin-induced changes in MT levels facilitate its intracellular transport. We have tested the effects of the Shiga toxin B subunit (STB) on MT-dependent and -independent transport steps. STB increases the rate of MT-dependent Golgi stack repositioning after nocodazole treatment. It also enhances the MT-dependent accumulation of transferrin in a perinuclear recycling compartment. By contrast, the rate of MT-independent transferrin recycling is not significantly different when STB is present. We found that STB normally requires MTs and dynein for its retrograde transport to the juxtanuclear Golgi complex and that STB increases MT assembly. Furthermore, we find that MT polymerization is limiting for STB transport in cells. These results show that STB-induced changes in cytoskeletal dynamics influence intracellular transport. We conclude that the increased rate of MT assembly upon Shiga toxin binding facilitates the retrograde transport of the toxin through the secretory pathway.
Activity-dependent Reversible Inactivation of the General Amino Acid Permease
Authors: Risinger April L. , Cain Natalie E. , Chen Esther J. , Kaiser Chris A.
Published: August 2006

The general amino acid permease, Gap1p, of Saccharomyces cerevisiae transports all naturally occurring amino acids into yeast cells for use as a nitrogen source. Previous studies have shown that a nonubiquitinateable form of the permease, Gap1pK9R,K16R, is constitutively localized to the plasma membrane. Here, we report that amino acid transport activity of Gap1pK9R,K16Rcan be rapidly and reversibly inactivated at the plasma membrane by the presence of amino acid mixtures. Surprisingly, we also find that addition of most single amino acids is lethal to Gap1pK9R,K16R-expressing cells, whereas mixtures of amino acids are less toxic. This toxicity appears to be the consequence of uptake of unusually large quantities of a single amino acid. Exploiting this toxicity, we isolated gap1 alleles deficient in transport of a subset of amino acids. Using these mutations, we show that Gap1p inactivation at the plasma membrane does not depend on the presence of either extracellular or intracellular amino acids, but does require active amino acid transport by Gap1p. Together, our findings uncover a new mechanism for inhibition of permease activity in response to elevated amino acid levels and provide a physiological explanation for the stringent regulation of Gap1p activity in response to amino acids.
Implementing cash for work programmes in post‐tsunami Aceh: experiences and lessons learned
Authors: Doocy Shannon , Gabriel Michael , Collins Sean , Robinson Courtland , Stevenson Peter
Published: August 2006

Cash for work (CFW) programmes are utilised in various disaster and emergency contexts and were a prominent component of the tsunami response in Aceh province, Indonesia. This paper describes Mercy Corps' CFW programme, discusses CFW implementation experiences and provides key recommendations for similar programmes in future emergencies. For the majority of CFW participants and their households, CFW was the only source of household income and 93 per cent of household incomes were attributable to it. The CFW programme empowered displaced populations to return to their communities; 91 per cent of participants indicated that CFW facilitated their return. Other reported psychosocial benefits included providing productive activities and giving communities an opportunity to work together. Mercy Corps' experience in Aceh demonstrates that cash disbursements can be safely delivered in a widespread manner in emergencies, and that when implemented on a short‐term basis, can have positive impacts at the individual and community level.
Tsunami mortality and displacement in Aceh province, Indonesia
Authors: Rofi Abdur , Doocy Shannon , Robinson Courtland
Published: August 2006

A survey of 388 Indonesian households displaced by the December 2004 tsunami was conducted in Aceh province in February 2005. Of tsunami‐displaced households in Aceh Barat and Nagan Raya districts, 61.8 per cent reported one or more family members as dead or missing1 due to the tsunami, with an overall mortality rate of 13.9 per cent (95% confidence interval (CI): 12.4–15.4). Risk of death was greatest in the youngest and oldest age groups, and among females. Overall, 36 per cent of tsunami‐displaced households indicated an intention to return to their original community within three months, and displaced households residing in host communities were 2.2 (95% CI: 1.2–2.8) times more likely to state an intention to return to their original villages or another community as those residing in camps. The tsunami recovery effort should focus on strategies that facilitate either prompt return or permanent, voluntary relocation for those displaced.
Proteomic and genetic approaches to identifying defence‐related proteins in rice challenged with the fungal pathogen Rhizoctonia solani
Authors: LEE JOOHYUN , BRICKER TERRY M. , LEFEVRE MICHAEL , PINSON SHANNON R. M. , OARD JAMES H.
Published: August 2006

Sheath blight, caused by the fungus Rhizoctonia solani, is a major disease of rice world‐wide, but little is known about the host response to infection. The objective of this study was to identify proteins and DNA markers in resistant and susceptible rice associated with response to infection by R. solani. Replicated two‐dimensional polyacrylamide gel electrophoresis experiments were conducted to detect proteins differentially expressed under inoculated and non‐inoculated conditions. Tandem mass spectra analysis using electrospray ionization quadrupole‐time of flight mass spectrometry (ESI Q‐TOF MS) was carried out for protein identification with the NCBI non‐redundant protein database. Seven proteins were increased after inoculation in both susceptible and resistant plants. Six of the seven proteins were identified with presumed antifungal, photosynthetic and proteolytic activities. An additional 14 proteins were detected in the response of the resistant line. Eleven of the 14 proteins were identified with presumed functions relating to antifungal activity, signal transduction, energy metabolism, photosynthesis, molecular chaperone, proteolysis and antioxidation. The induction of 3‐β‐hydroxysteroid dehydrogenase/isomerase was detected for the first time in resistant rice plants after pathogen challenge, suggesting a defensive role of this enzyme in rice against attack by R. solani. The chromosomal locations of four induced proteins were found to be in close physical proximity to genetic markers for sheath blight resistance in two genetic mapping populations. The proteomic and genetic results from this study indicate a complex response of rice to challenge by R. solani that involves simultaneous induction of proteins from multiple defence pathways.
Interactions between large African browsers and thorny Acacia on a wildlife ranch in Kenya
Authors: Milewski Antoni V. , Madden Derek
Published: August 2006

Some plants respond to browsing with compensatory regrowth of plant tissues and with increased thorn growth. Associations between browsers and their preferred forage were examined through wandering quarter vegetation sampling and observational studies in an effort to understand how some plants respond to browsing by large African herbivores. Acacia seyal (n = 2680) A. drepanolobium (n = 1850), and Balanites glabra (n = 960) were three species of frequently browsed indigenous plants examined on Game Ranching Ltd. in Kenya. There were several statistically significant associations revealed. Individual A. seyal exposed to intensive browser utilization were observed to lose shoot tips, produce long thorns, and have relatively few flowers and fruits. Browser utilization was associated with increased lateral branching in A. drepanolobium and with an increased occurrence of short, thickened spines in B. glabra. Thorns, spines and flowers were measurable indicators of relative browser utilization, and may be useful features to monitor in the management of large African mammals and their prickly forage
Presentation and comments on EU legislation related to food industries – environment interactions and waste management
Authors: Arvanitoyannis Ioannis S. , Tserkezou Persefoni , Choreftaki Stefania
Published: August 2006

Although environment remained for a long time at the very top of most advanced countries governments’ agenda priorities, and a series of protocols like Montreal (1987), Kyoto (2002), Conference in Rio de Janeiro (1992) and legislations (White and Green Paper, 2001 and 1996, respectively) were put forward among others, the global awareness towards the environment continues to be at a very low level. The main problem towards enforcing legislation is the high cost invoked by most industries and municipalities. However, recent advances in remediation, composting, recycling technology have shown that waste treatment can result in high added value products (i.e. biodiesel, fertiliser) and advantageous to the environment as well. European Union (EU) legislation is currently considered one of the well‐compiled and strict legislations compared with other advanced countries (USA, Canada and Japan). Although food industries are not included in the highly polluting ones, their great volume of waste materials generated, makes imperative their undertaking actions in this direction. This review aims at presenting all the EU laws (from the waste management perspective) in connection with the food industries and their interactions with the environment and vice versa.
Piper betle: a potential natural antioxidant
Authors: Arambewela Lakshmi , Arawwawala Menuka , Rajapaksa Damisha
Published: August 2006

Piper betle Linn. (Family: Piperaceae) is a common plant cultivated in Asian countries. The aim of this study was to evaluate the antioxidant potential and possible applications of P. betle leaves grown in Sri Lanka. This was carried out using P. betle cold ethanolic extract (CEE), hot water extract (HWE) and essential oil (EO). The initial free radical scavenging activity of CEE was higher than that of butylated hydroxyl toluene (BHT). Further, antioxidant activity of CEE, EO and HWE did not significantly deviate from the initial antioxidant activity up to 12 months. However, at elevated temperature (200 °C) antioxidant activity was significantly reduced (EC50 values of CEE, EO and BHT increased by fourfold and HWE by threefold) compared to their initial values. The reduction of antioxidant activity of CEE was lesser than that of BHT. Peroxide values (PV) were significantly lower in CEE‐incorporated coconut and palm oil samples compared to that of BHT‐treated samples. Moreover, CEE extended the shelf‐life of potato chips and increased the stability of Aloe gel.
The antioxidant capacity of cocoa products: contribution to the Spanish diet
Authors: Tabernero Maria , Serrano Jose , Saura‐Calixto Fulgencio
Published: August 2006

Chocolate and soluble cocoa powders are dietary sources of antioxidants. The literature reports antioxidant capacity (AC) derived from aqueous‐organic extracts of cocoa polyphenols; however, the residue of these extracts contains appreciable amounts of nonextractable polyphenols (condensed tannins or proanthocyanidins), which may become bioactive antioxidants after colonic fermentation. The objective of this work was to determine the total AC of cocoa products including both extractable and nonextractable polyphenols. Three methods were used: ferric reducing/antioxidant power, 2,2,‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonic acid) cations’ free‐radical scavenging capacity. With this last method, AC ranged from 42 to 79 and from 22 to 60 μmol Trolox per gram of sample for extractable and nonextractable polyphenols, respectively. Addition of milk reduces the AC of cocoa products by about 30%. On the other hand, it was estimated that cocoa products account for about 10% of the total AC of the Spanish diet.
Total phenolic content and antioxidant activity in selected medicinal plants of Zimbabwe
Authors: Muchuweti Maud , Nyamukonda Lynet , Chagonda Larmet S. , Ndhlala Ashrrell R. , Mupure Chipo , Benhura Mudadi
Published: August 2006

Seven commonly known medicinal plants from Zimbabwe were analysed for their antioxidant activity as well as their total phenolic content. The plant samples used in this study were Albizia amara, Elionurus muticus, Heteropyxis natalensis, Hoslundia opposita, Lippia javanica, Ocimum urticifolia and Warburgia salutaris. The plant samples were extracted using 70% ethanol. The 2,2‐diphenyl‐1‐picrylhydrazyl radical assay was used to determine the antioxidant activity of the plant extracts, while the Folin–Ciocalteu method was used to determine the total phenolic content. The antioxidant activities of the plant extracts ranged from 95.84 ± 0.50% for E. muticus to 5.31 ± 4.47% for H. opposita. Total phenolics in the plant extract estimated as tannic acid equivalent (TAE) ranged from 0.098 ± 0.005 mg per 100 g for H. natalensis to 0.024 ± 0.006 TAE for H. opposita. There was a poor correlation (R = 0.522) between total phenolic content and antioxidant activity in the plant samples. The results indicate the presence of phenolic compounds as well as significant antioxidant activity.
Isolation and characterisation of antioxidant components from oregano (Origanum heracleoticum)
Authors: Tsimogiannis Dimitrios , Stavrakaki Maria , Oreopoulou Vassiliki
Published: August 2006

In this study, Origanum heracleoticum was examined as potential source of phenolic antioxidants. The components of the plant were extracted in a Soxhlet apparatus sequentially with solvents of increasing polarity, specifically with petroleum ether (P), diethyl ether (D) and ethanol (E); the ethanol extract was further fractionated to obtain a diethyl ether (ED) and an ethyl acetate (EEAc) fraction. The activity of the extracts to scavenge 2′2′‐diphenyl‐1‐picrylhydrazyl followed the order ED > E> D > EEAc >> P. Moreover, the antioxidant activity in refined cottonseed oil at a concentration of 500 ppm was monitored through peroxide value measurements and revealed that ED resulted in the highest decrease in the rate of peroxide formation followed by D. Specific flavonoids and rosmarinic acid were detected as the main components of D, ED through HPLC–DAD and HPLC–MS/MS analyses.
An update of US food safety, food technology, GM food and water protection and management legislation
Authors: Arvanitoyannis Ioannis S. , Tserkezou Persefoni , Varzakas Theodoros
Published: August 2006

US government was the first to introduce Hazard Analysis Critical Control Point, the system that had a tremendous impact on everybody's life starting from the food and packaging companies up to consumer themselves. The rest of the nations simply followed US approach with a considerable delay both in terms of legislation and implementation. In the case of genetically modified (GM) or genetically engineered foods, the situation was entirely different. United States benefited from the ‘dubious’, and definitely not proved, ‘substantial equivalence’ principle invoked as the most practical approach to assess the safety of GM foods and food ingredients. US legislation appeared to be considerably more lenient than the European Union. The latter required many more analyses and labelling of GM food or food components. In this article, an update is attempted of the entire US legislation falling in fields like food safety, food technology, GM foods and finally legislation referring to specific foods (animal origin – meat, poultry, fish, dairy; and agricultural produces – vegetables, fruits) and water quality by means of fourteen comprehensive tables.