Heated Optical Fiber for Distributed Soil-Moisture Measurements: A Lysimeter Experiment

An Actively Heated Fiber Optics (AHFO) method to estimate soil moisture is tested and the analysis technique improved on. The measurements were performed in a lysimeter uniformly packed with loam soil with variable water content profiles. In the first meter of the soil profi le, 30 m of fiber optic cable were installed in a 12 loops coil. The metal sheath armoring the fiber cable was used as an electrical resistance heater to generate a heat pulse, and the soil response was monitored with a Distributed Temperature Sensing (DTS) system. We study the cooling following three continuous heat pulses of 120 s at 36 W m(-1) by means of long-time approximation of radial heat conduction. The soil volumetric water contents were then inferred from the estimated thermal conductivities through a specifically calibrated model relating thermal conductivity and volumetric water content. To use the pre-asymptotic data we employed a time correction that allowed the volumetric water content to be estimated with a precision of 0.01-0.035 (m(3) m(-3)). A comparison of the AHFO measurements with soil-moisture measurements obtained with calibrated capacitance-based probes gave good agreement for wetter soils [discrepancy between the two methods was less than 0.04 (m(3) m(-3))]. In the shallow drier soils, the AHFO method underestimated the volumetric water content due to the longertime required for the temperature increment to become asymptotic in less thermally conductive media [discrepancy between the two methods was larger than 0.1 (m(3) m(-3))]. The present work suggests that future applications of the AHFO method should include longer heat pulses, that longer heating and cooling events are analyzed, and, temperature increments ideally be measured with higher frequency.

Consumption of macrophytes by invertebrates in Tancada lagoon (NE Spain)

Gammarus aequicauda and Sphaeroma hookeri are the most abundant macroinvertebrates on Ruppia cirrhosa (1275 and 1290 individuals.m-2) and Potamogeton pectinatus (140 and 680 individuals. m-2) in Tancada lagoon, a Mediterranean coastal lagoon in the Ebro Delta (NE Spain). Consumption and assimilation efficiencies were calculated from bell jar experiments. Gammarus grazing effects are higher than Sphaeroma on both Ruppia cirrhosa and Potamogeton pectinatus. Green Ruppia leaves lost 0.3 mg per mg Gammarus per day, while Potamogeton leaves lost 0.2 mg per mg Gammarus per day. Decomposing Ruppia leaves lost 0.35-0.54 mg per mg Gammarus per day. Losses of weight by both Ruppia and Potamogeton due to Sphaeroma feeding were less than half those by Gammarus. Assimilation efficiencies are higher for Gammarus (44-78% feeding on Ruppia 2% feeding on Potamogeton) than for Sphaeroma (26-48%) feeding on Ruppia). These assimilation efficiencies were higher than those reported by other authors working at higher latitudes perhaps because of the higher temperature under which the experiments were carried out.

Coffee consumption attenuates short-term fructose-induced liver insulin resistance in healthy men.

BACKGROUND: Epidemiologic and experimental data have suggested that chlorogenic acid, which is a polyphenol contained in green coffee beans, prevents diet-induced hepatic steatosis and insulin resistance. OBJECTIVE: We assessed whether the consumption of chlorogenic acid-rich coffee attenuates the effects of short-term fructose overfeeding, dietary conditions known to increase intrahepatocellular lipids (IHCLs), and blood triglyceride concentrations and to decrease hepatic insulin sensitivity in healthy humans. DESIGN: Effects of 3 different coffees were assessed in 10 healthy volunteers in a randomized, controlled, crossover trial. IHCLs, hepatic glucose production (HGP) (by 6,6-d2 glucose dilution), and fasting lipid oxidation were measured after 14 d of consumption of caffeinated coffee high in chlorogenic acid (C-HCA), decaffeinated coffee high in chlorogenic acid, or decaffeinated coffee with regular amounts of chlorogenic acid (D-RCA); during the last 6 d of the study, the weight-maintenance diet of subjects was supplemented with 4 g fructose · kg(-1) · d(-1) (total energy intake ± SD: 143 ± 1% of weight-maintenance requirements). All participants were also studied without coffee supplementation, either with 4 g fructose · kg(-1) · d(-1) (high fructose only) or without high fructose (control). RESULTS: Compared with the control diet, the high-fructose diet significantly increased IHCLs by 102 ± 36% and HGP by 16 ± 3% and decreased fasting lipid oxidation by 100 ± 29% (all P < 0.05). All 3 coffees significantly decreased HGP. Fasting lipid oxidation increased with C-HCA and D-RCA (P < 0.05). None of the 3 coffees significantly altered IHCLs. CONCLUSIONS: Coffee consumption attenuates hepatic insulin resistance but not the increase of IHCLs induced by fructose overfeeding. This effect does not appear to be mediated by differences in the caffeine or chlorogenic acid content. This trial was registered at clinicaltrials.gov as NCT00827450.

Performance of Randomly Oriented, Fiber-Reinforced Roadway Soils, HR-211, 1982

Several primary techniques have been developed through which soil aggregate road material properties may be improved. Such techniques basically involve a mechanism of creating a continuous matrix system of soil and/or aggregate particles, interlocked through the use of some additive such as portland cement, lime, or bituminous products. Details by which soils are stabilized vary greatly, but they are dependent on the type of stabilizing agent and nature of the soil, though the overall approach to stabilization has the common feature that improvement is achieved by some mechanism(s) forcing individual particles to adhere to one another. This process creates a more rigid material, most often capable of resisting the influx of water during freezing, loss of strength due to high moisture content and particle dispersion during thawing, and loss of strength due to migration of fines and/or water by capillarity and pumping. The study reported herein, took a new and relatively different approach to strengthening of soils, i.e., improvement of roadway soils and/or soil-aggregate materials by structural reinforcement with randomly oriented fibers. The purpose of the study was to conduct a laboratory and field investigation into the potential of improving (a) soil-aggregate surfaced and subgrade materials, including those that are frost-prone and/or highly moisture susceptible, and (b) localized base course materials, by uniting such materials through fibrous reinforcement. The envisioned objective of the project was the development of a simple construction technique(s) that could be (a) applied on a selective basis to specific areas having a history of poor performance, or (b) used for improvement of potential base materials prior to surfacing. Little background information on such purpose and objective was available. Though the envisioned process had similarities to fibrous reinforced concrete, and to fibrous reinforced resin composites, the process was devoid of a cementitious binder matrix and thus highly dependent on the cohesive and frictional interlocking processes of a soil and/or aggregate with the fibrous reinforcement; a condition not unlike the introduction of reinforcing bars into a concrete sand/aggregate mixture without benefit of portland cement. Thus the study was also directed to answering some fundamental questions: (1) would the technique work; (2) what type or types of fibers are effective; (3) are workable fibers commercially available; and (4) can such fibers be effectively incorporated with conventional construction equipment, and employed in practical field applications? The approach to obtaining answers to these questions, was guided by the philosophy that an understanding of basic fundamentals was essential to developing a body of engineering knowledge, that would serve as the basis for eventual development of design procedures with fibrous products for the applications previously noted.

The influence of tobacco consumption on the relationship between schizotypy and hemispheric asymmetry.

Tobacco use is positively associated with severity of symptoms along the schizophrenia spectrum. Accordingly it could be argued that neuropsychological performance, formerly thought to be modulated by schizotypy, is actually modulated by drug use or an interaction of drug use and schizotypy. We tested whether habitual cigarette smokers as compared to non-smokers would show a neuropsychological profile similar to that observed along the schizophrenia spectrum and, if so, whether smoking status or nicotine dependence would be more significant modulators of behavior than schizotypy. Because hemispheric dominance has been found to be attenuated along the schizophrenia spectrum, 40 right-handed male students (20 non-smokers) performed lateralized left- (lexical decisions) and right- (facial decision task) hemisphere dominant tasks. All individuals completed self-report measures of schizotypy and nicotine dependence. Schizotypy predicted laterality in addition to smoking status: While positive schizotypy (Unusual Experiences) was unrelated to hemispheric performance, Cognitive Disorganization predicted reduced left hemisphere dominant language functions. These latter findings suggest that Cognitive Disorganization should be regarded separately as a potentially important mediator of thought disorganization and language processing. Additionally, increasing nicotine dependence among smokers predicted a right hemisphere shift of function in both tasks that supports the role of the right hemisphere in compulsive/impulsive behavior.

Oral tongue squamous cell carcinoma (OTSCC): alcohol and tobacco consumption versus non-consumption. A study in a Portuguese population

There has been an increase in the incidence of carcinoma of the tongue, particularly among alcohol and tobacco non-users. However, the number of studies that would allow a better understanding of etiological factors and clinical features, particularly in the Portuguese population, is very limited. This study was based on patients with squamous cell carcinoma of the anterior two thirds of the tongue that were treated at the Department of Head and Neck Surgery of the ¿Instituto Portugues de Oncologia de Lisboa - Francisco Gentil" IPOLFG) in Lisbon, Portugal, between January 1, 2001 and December 31, 2009. The patients were divided in alcohol and tobacco users and non-users in order to evaluate the differences between these 2 groups based on gender, age, tumor location, denture use, and tumor size, metastasis and stage. Of the 354 cases, 208 were users and 146 were non-users. The main location in both groups was the lateral border of the tongue. Denture use showed no significant effect in both study groups. It was possible to conclude that patients who did not drink or smoke were older and presented with smaller tumor size, lower incidence of ganglion metastasis and lower tumor stage compared with alcohol and tobacco users.

Deposition and residues of azoxystrobin and imidacloprid on greenhouse lettuce with implications for human consumption

Lettuce greenhouse experiments were carried out from March to June 2011 in order to analyze how pesticides behave from the time of application until their intake via human consumption taking into account the primary distribution of pesticides, field dissipation, and post-harvest processing. In addition, experimental conditions were used to evaluate a new dynamic plant uptake model comparing its results with the experimentally derived residues. One application of imidacloprid and two of azoxystrobin were conducted. For evaluating primary pesticide distribution, two approaches based on leaf area index and vegetation cover were used and results were compared with those obtained from a tracer test. High influence of lettuce density, growth stage and type of sprayer was observed in primary distribution showing that low densities or early growth stages implied high losses of pesticides on soil. Washed and unwashed samples of lettuce were taken and analyzed from application to harvest to evaluate removal of pesticides by food processing. Results show that residues found on the Spanish preharvest interval days were in all cases below officially set maximum residue limits, although it was observed that time between application and harvest is as important for residues as application amounts. An overall reduction of 40–60% of pesticides residues was obtained from washing lettuce. Experimentally derived residues were compared with modeled residues and deviate from 1.2 to 1.4 for imidacloprid and azoxystrobin, respectively, presenting good model predictions. Resulting human intake fractions range from... for imidacloprid to ... for azoxystrobin.

L'éthylglucuronide: un marquer de la consommation d'alcool [Ethyl glucuronide: a biomarker of alcohol consumption]

Excessive alcohol consumption represents a major risk factor for morbidity and mortality. It is therefore indispensable to be able to detect at-risk drinking. Ethyl glucuronide (EtG) is a specific marker of alcohol consumption. The determination of ethyl glucuronide in urine or blood can be used to prove recent driving under the influence of alcohol, even if ethanol is no longer detectable. The commercialization of an EtG specific immunological assay now allows to obtain preliminary results rapidly and easily with satisfying sensitivity. Moreover, the detection of ethyl glucuronide in hair offers the opportunity to evaluate an alcohol consumption over a long period. The EtG concentration in hair is in correlation with the amount of ingested alcohol. Thus, the analysis of ethyl glucuronide can be used to monitor abstinence, to detect alcohol relapse and to identify at-risk drinkers. However, a cut off allowing to detect chronic alcohol abuser reliably still does not exist. Therefore, it is recommended to perform the analysis of ethyl glucuronide in complement to the existing blood markers. A study financed by the Swiss Foundation for Alcohol Research is actually conducted by the West Switzerland University Center of Legal Medicine in order to establish an objective cut-off.

Assessing the environmental impact of water consumption by energy crops grown in Spain

The environmental impact of the water consumption of four typical crop rotations grown in Spain, including energy crops, was analyzed and compared against Spanish agricultural and natural reference situations. The life cycle assessment (LCA) methodology was used for the assessment of the potential environmental impact of blue water (withdrawal from water bodies) and green water (uptake of soil moisture) consumption. The latter has so far been disregarded in LCA. To account for green water, two approaches have been applied: the first accounts for the difference in green water demand of the crops and a reference situation. The second is a green water scarcity index, which measures the fraction of the soil-water plant consumption to the available green water. Our results show that, if the aim is to minimize the environmental impacts of water consumption, the energy crop rotations assessed in this study were most suitable in basins in the northeast of Spain. In contrast, the energy crops grown in basins in the southeast of Spain were associated with the greatest environmental impacts. Further research into the integration of quantitative green water assessment in LCA is crucial in studies of systems with a high dependence on green water resources.

Consommation d'aliments riches en calcium dans la population adulte de Suisse romande et du Tessin. [Consumption of calcium-rich food in the adult population of French-speaking Switzerland and of Tessin].

Food intake high in calcium content is important in the development of skeleton and the prevention of osteoporosis. From a public health perspective, it is therefore important to know the dietary calcium intake of a population. Two population surveys in the French and Italian parts of Switzerland (MONICA, 1988-1989, and Geneva, 1991), were combined to study nutritional habits related to calcium intake. A random population sample, aged 35 et 65 years, answered to a 24 hour recall questionnaire, either self-administered (MONICA, cantons of Vaud, Fribourg and Tessin, N = 2734) or by phone (canton of Geneva, N = 475). In the 4 cantons, for the previous day, 60% of participants ate dairy products, particularly whole milk and cheese. They drunk 3-4 dl/day of milk. A significant proportion (10%) of french and italian speaking Swiss did not consume any food high in calcium content. In Geneva, the mean daily calcium intake was 656 mg in men and 489 mg in women. In conclusion 1) eating habits related to calcium intake are similar across cantons; 2) women consume dairy products more frequently than men, but in smaller quantities; 3) about 60% of men and 80% of women do not get the daily amount of calcium recommended for the prevention of osteoporosis.

Investigation of Glass Fiber Composite Dowel Bars for Highway Pavement Slabs, TR-408, 2001

Contractors, engineers, owners and manufacturers want to be certain that a new product or procedure will yield beneficial results when compared to the current method of construction. The following research was conducted in order to compare the performance of epoxy coated dowel bars to dowel bars of alternative shapes and materials such as stainless steel and glass fiber reinforced polymer (GFRP). Research was also done on the effect that dowel bar spacing has on the performance of concrete pavements. Four phases of this research are described in this report.