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The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together.
Carbon nanotubes (CNTs) were synthesized by Chemical Vapor Deposition (CVD) from diethyl ether, butanol, hexane and ethyl acetate. A quartz tube with a stainless steel tube catalyst core with 0.019 m diameter and 0.6 m large formed the reactor. To avoid combustion, argon was used as the carrier gas. Time process ranged 30 to 60 min. The range of CNTs synthesis temperature was 680-850 °C for different precursors. Scanning Electron Microscopy micrographs have demonstrated tangled CNTs growth in all samples, thus presenting difficult length measurement. The CNTs diameters from diethyl ether are 45-200 nm, butanol diameter range from 55-230 nm, hexane diameter range is 50-130 nm and ethyl acetate range from 100 to 300 nm. Carbon content for all samples was higher than 93 %, CNTs from butanol showed carbon concentration up to 99%. FTIR, Raman and X-Ray Spectroscopies spectra for all samples demonstrated the characteristics signals present in carbon nanotubes. This research proposes a simple, effective and innovative method to synthesize CNTs by CVD on iron stainless steel catalyst in combination with diethyl ether, ethyl acetate, butanol and hexane as precursors by applying the principles of green chemistry, sustainability and its ease to be scaled.
The objectives were to assess the following: (1) the relationship between sward height and chemical composition of four pasture types in association with grazing behaviour and body condition score (BCS) of dairy cows, and (2) the possibility of developing predictive equations of the nutrient intake and grazing behaviour within a continued grazing system. Pasture type had a significant (p < 0.01) effect on nutrient supply from January to June for all pastures investigated. Ryegrass–white clover pasture (RW) had the highest metabolizable protein and metabolizable energy, followed by kikuyu pasture (KP), which was significantly (p < 0.001) higher than native pastures 1 and 2 (NP1 and NP2). The highest values for effective grazing time, bite rate and BCS were found when dairy cows grazed RW followed by KP, NP2 and NP1. The results suggested that pasture type and sward height influenced grazing behaviour and BCS of dairy cows during the dry season. In the same vein, RW showed higher effective grazing time, bite rate, nutrient intake and BCS than the other three pastures suggesting that RW pastures that appear to be more expensive than native pastures could result in superior cow performance.
This retrospective study aimed to evaluate the effective closure rate for spontaneous cerebrospinal fluid leaks with functional endoscopic sinus surgery and identify patient characteristics that may be associated with a need for additional therapy.
A retrospective analysis of patients with spontaneous cerebrospinal fluid leaks was performed. Data on the nature of presentation, patient body mass index, defect location and size, intracranial pressure, clinical follow up, and complications were collected.
Twenty-five patients had spontaneous cerebrospinal fluid leaks with evidence of idiopathic intracranial hypertension. The most common sites were the cribriform plate, followed by the ethmoid roof and sphenoid lateral pterygoid recess. All patients underwent endonasal endoscopic surgery to repair the defect. Post-operatively, all patients underwent lumbar drainage and acetazolamide therapy.
Spontaneous cerebrospinal fluid leaks represent a surgical challenge because of their high recurrence rates. The most important factor for obtaining a successful repair in these patients is reducing their intracranial pressure through nutritional, medical or surgical means.
In this paper, we give lower bounds for the fundamental tone of open sets in minimal submanifolds immersed into warped product spaces of type Nn ×f Qq, where f ∈ C∞(N). This setting allows us to deal, among other things, with minimal submanifolds bounded by cylinders, cones, spheres and pseudo-hyperbolic spaces where most of these examples are not covered in the literature. Applications also include the study of the essential spectrum of hyperbolic graphs over compact regions of the boundary at infinity.
Dendrons with a porphyrin core and π-conjugated dendron branches have been synthesized and characterized. The dendrons showed an all trans configuration. Cubic non-linear optical behavior of the styryl and porphyrin-containing dendrimers was tested viaZ-Scan measurements in spin-coated film samples.
To study the effect of the film/substrate interface in thin films we have analyzed the thickness dependence of the transport properties of SrRuO3 films grown on SrTiO3 substrates. Our data makes evident the failure of the so-called deadlayer model to describe the observed thickness dependence of the conductivity. This is interpreted as due to a non-monotonous change of microstructure as thickness increases. Indeed, Atomic Force Microscopy studies indicate substantial modifications of the growth mechanism with thickness.
Cyclodextrin (CD) has been studied intensively due to its ability to form inclusion complexes with a variety of guest molecules in the solid state. A few studies have paid attention to the use of CD to facilitate the synthesis of inorganic nanoparticles. In this work the synthesis of magnetite (M) is made in the presence of CD. The particle size of the inorganic material is controlled by the presence of CD, in which spherical particles of few nanometers are grown. The synthesis of Fe3O4 (M) in the presence of α-cyclodextrin (α-CD) and β-cyclodextrin (βCD) is described. The formation of an M-CD complex is studied in both cases by Fourier transform infrared spectroscopy (FT-IR) in order to elucidate the chemical bonding of the complex. The morphology and size of the particles are determined by Field Emission Scanning Electron Microscopy (FESEM) and software. X-ray diffraction (XRD) is used to confirm the formation of magnetite.
Polyurethanes are interesting materials that can be used in biomedical applications for regeneration of bone tissue. In this work the synthesis and characterization of porous polyurethanes to act as scaffold is performed by a thermally induced phase separation technique. The appropriate parameters are determined in order to obtain a porous well interconnected material. Characterization by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is made in order to determine the thermal stability of the material. Chemical characterization is made by Fourier transformed infrared spectroscopy with attenuated total reflectance (FTIR-ATR). The morphology of the material is observed by a field emission scanning electron microscope (FESEM) and the mechanical properties are measured by dynamic mechanical analysis (DMA).
It has become widely accepted that cognitive deficits in schizophrenia are related to functional outcome. However, it remains to be seen whether these associations are relevant for predicting which cases will have a global functional recovery. In this study, we attempt to determine whether global functional recovery (integrating social and occupational outcomes) after first-episode schizophrenia (FES) can be predicted by cognitive variables.
A total of 131 FES patients with functional deficits (n=97) and functional recovery (n=34) as determined at 1-year follow-up were examined. Neuropsychological, sociodemographic, pre-morbid and clinical data at baseline were analysed using independent groups comparisons and a logistic regression method.
Sustained attention and negative symptoms emerged as significant predictors of good global functional outcome. Although the model revealed a high accuracy (91%) in the classification of patients with functional deficits, it was unacceptably low (26%) in the classification of patients with global functional recovery.
The limitations found in the prediction of a favourable global functional outcome may well be an indication for a need to address the role of other factors not commonly included in longitudinal studies of long-term outcomes in schizophrenia.
In Spain, trichinellosis represents a public health problem, with an average of five outbreaks per year, wild boar meat being the main source of infection. A trichinellosis survey (2007–2008 hunting campaign) was carried out on wild boars in the Toledo Mountains (south-western Spain, EU) in the context of a surveillance programme on wildlife diseases. A total of 2216 wild boars from different locations of the region were examined. The examination was carried out by veterinarians in the local abattoir (Matadero Municipal de Toledo). The positive samples were sent to the Department of Parasitology (Facultad de Farmacia, UCM) for experimental isolation and specific identification by inter-simple sequence repeat-polymerase chain reaction (ISSR-PCR). Using this technique we identified 17 isolates as Trichinella spiralis with an electrophoretic profile indistinguishable from the T. spiralis reference strain (ISS48). We confirmed that ISSR-PCR is a robust technique for the molecular identification of Trichinella isolates. According to our results, the prevalence of T. spiralis in wild boars from the Toledo Mountains (>800 m above sea level) during the hunting season was approximately 0.77%. The prevalence of T. spiralis (100% of our observations) is a good example of the persistence of this species in sylvatic conditions (coming from the domestic cycle), if a good wild host is abundant. Our observations confirm the major prevalence of T. spiralis over T. britovi in this region, as well as the risk to human health represented by the consumption of uninspected wild boar meat.
From 1979 to August 1987, there have been 178 cases of meningococcal disease in Iquique, Chile, a city of about 140000. The attack rate for the last 5 years has been in excess of 20/100000 per year, more than 20 times greater than for the country overall. The mortality rate was 6%. The disease occurred in patients with ages from 4 months to 60 years, but 89% of cases were in patients <21 years. The largest number of cases were in the age group 5–9 years (n = 54), but the highest incidence occurred in children less than 1 year of age (72·8/100000 per year). The male/female ratio was 1·2. Cases occurred all year round with little seasonal variation. Of the 178 cases, 173 were biologically confirmed. Serogroup analysis of strains from 135 patients revealed A = 1, B = 124, C = 10. Forty-four group B strains from 1985–7 were serotyped: 15:P1.3 = 36, 15:NT = 4, 4:P1.3 = 2, NT:NT = 2. Ten of 11 of the outbreak strains tested were sulfadiazine-resistant. This is the first recognized outbreak caused by a Gp B:15 strain in South America. It shares many of the characteristics of outbreaks caused by closely related strains in Europe, such as a predilection for older children and adolescents, sulfadiazine-resistance, and sustained high attack rates. The Iquique strain (B:15:P1.3) belongs to the same genetic clone (ET-5 complex) as the Norway (B:15:P1.16) and the Cuban (B:4:P1.15) strains.
A Neospora caninum 17–19 kDa antigenic protein fraction (p17) in one-dimensional polyacrylamide gel electrophoresis (SDS-PAGE) is the immunodominant antigen recognized by sera from bovines naturally infected by N. caninum. To identify the proteins making up the p17 fraction, we screened a new N. caninum tachyzoite cDNA library with an affinity-purified antibody against p17 (APA17). We isolated several cDNA clones with 100% sequence identity to the NcGRA7 gene. This previously described gene encodes a dense granule protein with an apparent molecular mass of 33 kDa. A second line of evidence emerged through a combined proteomic approach associating two-dimensional PAGE (2D-PAGE) to Western blotting and to mass spectrometry to characterize the p17 fraction. Two acidic immunodominant but minority protein spots were recognized by APA17 and by bovine sera. These antigens of 17 and 33 kDa are respectively composed of 4 and 2 isoforms. Furthermore, p17 isolation by 2D-PAGE and peptide sequencing by tandem mass spectrometry yielded a partial sequence of 17 amino acids, which allowed the putative amino terminal region of the NcGRA7 protein to be identified unambiguously.The NcGRA7 protein, without the putative signal peptide at the NH2-terminus, was cloned and expressed in Escherichia coli and when the purified recombinant protein (rNcGRA7) was analysed by SDS-PAGE and mass spectrometry, 2 bands of 24 and 33 kDa were resolved and identified as NcGRA7. These results demonstrate that the immunodominant 17 kDa antigen of N. caninum is encoded by the NcGRA7 gene.
To evaluate the consumption of added fats and oils across the European centres and countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC).
Design and setting:
24-Hour dietary recalls were collected by means of standardised computer-guided interviews in 27 redefined EPIC centres across 10 European countries.
From an initial number of 36 900 subjects, single dietary recalls from 22 924 women and 13 031 men in the age range of 35–74 years were included.
Mean daily intake of added fats and oils varied between 16.2 g (Varese, Italy) and 41.1 g (Malmö, Sweden) in women and between 24.7 g (Ragusa, Italy) and 66.0 g (Potsdam, Germany) in men. Total mean lipid intake by consumption of added fats and oils, including those used for sauce preparation, ranged between 18.3 (Norway) and 37.2 g day−1 (Greece) in women and 28.4 (Heidelberg, Germany) and 51.2 g day−1 (Greece) in men. The Mediterranean EPIC centres with high olive oil consumption combined with low animal fat intake contrasted with the central and northern European centres where fewer vegetable oils, more animal fats and a high proportion of margarine were consumed. The consumption of added fats and oils of animal origin was highest in the German EPIC centres, followed by the French. The contribution of added fats and oils to total energy intake ranged from 8% in Norway to 22% in Greece.
The results demonstrate a high variation in dietary intake of added fats and oils in EPIC, providing a good opportunity to elucidate the role of dietary fats in cancer aetiology.
To describe the trends of self-reported past consumption of alcoholic beverages and ethanol intake from 1950 to 1995 within the European Prospective Investigation into Cancer and Nutrition (EPIC).
Data on consumption of beer/cider, wine and liqueur/spirits were obtained retrospectively at age 20, 30 and 40 years to calculate average consumption and ethanol intake for the time periods 1950–1975 (at age 20), 1960–1985 (at age 30) and 1970–1995 (at age 40). Regression analysis was conducted with the time period data to assess trends in past alcoholic beverage consumption and ethanol intake with time.
The EPIC project.
In total, 392 064 EPIC participants (275 249 women and 116 815 men) from 21 study centres in eight European countries.
Generally, increases in beer/cider consumption were observed for most EPIC centres for 1950–1975, 1960–1985 and 1970–1995. Trends in wine consumption differed according to geographical location: downward trends with time were observed for men in southern European EPIC centres, upward trends for those in middle/northern European study centres. For women, similar but less pronounced trends were observed. Because wine consumption was the major contributor to ethanol intake for both men and women in most study centres, time trends for ethanol intake showed a similar geographical pattern to that of wine consumption.
The different trends in alcoholic beverage consumption and ethanol intake suggest that information depicting lifetime history of ethanol intake should be included in analyses of the relationship between ethanol and chronic diseases, particularly in multi-centre studies such as EPIC.
Concentrates are the main cash expenditure in smallholder campesino dairying in the highlands of Central Mexico. Improved, low-cost, appropriate feeding strategies have been therefore identified by campesinos as a priority. An on-farm trial was undertaken in 1998 to evaluate the response to supplementation with concentrates by dairy cows in early lactation during the rainy season with restricted access to grazing of ryegrass/white clover pastures. A base of 3·0 kg commercial concentrate/cow/day (S3) was compared against the higher rate used by farmers of 5·0 kg/cow/day (S5). Three farmers with one, and one farmer with two pairs of freshly calved upgraded Holstein cows participated in the trial (24±10·7 days into lactation). Data were analysed by a random block split-plot design where supplementation treatments were main plots and measurement periods were split-plots. Milk yield was recorded once per week for 9 weeks, and live weight and condition score for four 28 day periods. Milk yields were 21·8 for S3 and 21·9 for S5 (±0·714) kg milk/day/cow (P > 0·05); live weight S3 = 444·0 and S5 = 496·0 (±12·663) kg/cow (P > 0·05), and condition score S3 = 1·9, and S5 = 1·8 (±1·127) (P >0·05). There were no significant (P> 0·05) effects of measurement periods, and there was no significant (P > 0·05) interaction. The lack of response in milk yield, live weight or condition score to increased concentrate supplementation demonstrates that at these levels of production and management, the access to grazing of improved pastures, plus limited concentrate, enables cows in campesino systems to meet their nutrient requirements, and the feasibility of efficient milk production from grazed pastures as an appropriate technology. It is also concluded that it is an appropriate technology and that the results have implications for research and extension workers in rural development who have promoted large amounts of concentrate to dairy cows as the only way towards high yields and efficient milk production.
In the previous paper it was concluded that those aged [ges ] 15 years of both sexes could comprise the indicator group for
rapid epidemiological assessment (REA) of onchocerciasis in the Amazonian focus. This paper explores relationships
between community microfilarial (mf) prevalence, intensity, and nodule prevalence in 20 Yanomami communities, that
would allow identification of REA methods in the region. The mean nodule ratio (prevalence of nodules/prevalence of
mf) was 0·54 when onchocercomata in the indicator group were considered. The Spearman correlation coefficient between
mf and nodule prevalence was 0·686 (P = 0·001). Palpation of nodules had 92% specificity and 32% sensitivity when
compared to skin-snipping for the diagnosis of onchocerciasis. The predictive value positive increased from 75% to 81%
when the indicator group was used. A microfilarial prevalence > 75% in this group would be indicative of hyperendemic
status in the village, between 30 and 75% of mesoendemicity, and < 30% of hypoendemicity. For the assessment of
infection intensity, biopsies may be taken from the iliac crest for all endemicity levels. Five of the hyperendemic villages
surveyed in this work had a community microfilarial load (CMFL) greater than 10 mf/skin snip; the remaining 5 had a
CMFL between 5 and 9. These levels of infection merit high priority ivermectin treatment. In Latin America, communities
at both moderate and severe risk are included in mass chemotherapy programmes (i.e. when mf prevalence is
over 20%). Roughly, a nodule prevalence in the indicator group > 10% would suggest a community mf prevalence
> 20% with a sensitivity of 85% and a specificity of 71%. A multiple linear regression model of the arc-sine transformed
mf prevalence in the village (all ages) on nodule prevalence in those aged [ges ] 15 years and altitude of the village explained
72% of the variance. The model combining nodule and altitudinal information had a sensitivity of 92% and a specificity
of 71% in comparison to an estimated mf prevalence of 21% or more. It is suggested that the usefulness of the REA
methods proposed be assessed in other areas of the Amazonian onchocerciasis focus.