DECOMPOSITION RATES OF SPENT FUNGAL REFUSE OF ATTA-SEXDENS (HYMENOPTERA, FORMICIDAE) AND IMPLICATIONS FOR ESTIMATING FORAGE INTAKE BY LEAF-CUTTING ANTS

Using simulated ceramic refuse chambers, field decomposition studies were performed on the spent fungal refuse of the lead-cutting ant Atta sexdens rubropilosa. Refuse half life was estimated at 40 days, with complete decomposition at 100 days. These results suggest that the conversion-factor method used to estimate forage input into leaf-cutting ant colonies must be corrected for decomposition, or serious estimation errors will occur.

Cultivation of Pleurotus ostreatus using supplemented spent oyster Mushroom substrate

Spent Agaricus and Pleurotus substrates are mainly used as components of amendments and growing substrates, but not in sufficient quantities to solve the problem of their accumulation in mushroom producing areas, where they represent a potential pollution risk. The mushroom growing sector in Spain generates about 5105 t of spent compost, while the EU, as a whole, produces more than 3.5106 t. Among alternative management applications, it is possible to reuse these wastes in the cultivation of mushrooms, as a casing material for growing Agaricus spp. and as substrate for growing other species. In this work, the application of commercial nutritional supplements (Calprozime, Champfood and Promycel), widely used in Agaricus cultivation, is evaluated for its possible use as additive to substrates, based on spent oyster mushroom substrate (SMS), for the cultivation of Pleurotus ostreatus. Using a mixture of straw and SMS (1:1, w/w) as base material, the addition of CaSO4 (50 g kg-1) and CaCO3 (10 g kg-1) and the above supplements at 20 g kg-1 brought about a remarkable increase in production compared with the substrate without any supplement. The biological efficiencies did not differ significantly from that obtained when a commercial substrate was used as control, reaching values of 48.9 kg/100 kg substrate (dry matter) when Calprozime was used as supplement. Sporophores harvested from the supplemented substrates presented a higher dry matter content than those obtained from both commercial and non-supplemented substrates. SMS is cheap and easily available; it can be integrated into new formulations with the added advantages of lowering production costs, limiting growers' dependence on straw, and decreasing the environmental impact of its ever-growing accumulation.

Production, purification, and characterization of a major penicillium glabrum xylanase using brewer's spent grain as substrate

In recent decades, xylanases have been used in many processing industries. This study describes the xylanase production by Penicillium glabrum using brewer's spent grain as substrate. Additionally, this is the first work that reports the purification and characterization of a xylanase using this agroindustrial waste. Optimal production was obtained when P. glabrum was grown in liquid medium in pH 5.5, at 25 °C, under stationary condition for six days. The xylanase from P. glabrum was purified to homogeneity by a rapid and inexpensive procedure, using ammonium sulfate fractionation and molecular exclusion chromatography. SDS-PAGE analysis revealed one band with estimated molecular mass of 18.36 kDa. The optimum activity was observed at 60 °C, in pH 3.0. The enzyme was very stable at 50 °C, and high pH stability was verified from pH 2.5 to 5.0. The ion Mn2+ and the reducing agents β-mercaptoethanol and DTT enhanced xylanase activity, while the ions Hg2+, Zn2+, and Cu2+ as well as the detergent SDS were strong inhibitors of the enzyme. The use of brewer's spent grain as substrate for xylanase production cannot only add value and decrease the amount of this waste but also reduce the xylanase production cost. © 2013 Adriana Knob et al.

Seroprevalence of salmonella and mycoplasma in commercial broilers, backyard chickens, and spent hens in the region of Triangulo Mineiro, state of Minas Gerais, Brazil

Avian salmonellosis and mycoplasmosis are infectious diseases that, in addition of causing lack of flock uniformity, represent a hazard to human health. The objective of the present study was to evaluate the seroprevalence of mycoplasmosis and salmonellosis in commercial broilers, backyard chickens, and spent hens slaughtered at a processing plant with local health inspection in Uberlandia, MG, Brazil. A total of 210 samples were randomly collected at the time of bleeding. Samples were submitted to rapid plate serum agglutination test (RSA) for the classification of Salmonella pullorum, Salmonella gallinarum, Mycoplasma gallisepticum and Mycoplasma synoviae. In order to increase result specificity, mycoplasmosis-positive samples were submitted to hemagglutination inhibition test (HI). No samples presented detectable antibodies against Salmonella pullorum or Salmonella gallinarum in the RSA test. Only Mycoplasma synoviae was detected in 14% of the backyard chickens and 0.74% in commercial broilers, whereas no antibodies were detected in spent hens. The seroprevalence rates found in the present study emphasize the need of keeping chicken flocks free from disease using effective biosafety systems.

Use of high-resolution thermogravimetric analysis (HRTG) technique in spent FCC catalyst/Portland cement pastes

Thermogravimetric analysis is one of the most common instrumental techniques used for the characterization of pastes, mortars and concretes based on both calcium hydroxide and Portland cement. Important information about pozzolanic materials can be assessed concerning calcium hydroxide consumption and the formation of new hydrated products. Nevertheless, in some cases, problems associated with the overlapped decomposition processes for hydrates make the analysis of obtained data difficult. In this paper, the use of high-resolution thermogravimetric analysis, a powerful technique that allows separating decomposition processes in analysis of hydrated binders, was performed for spent FCC catalyst-Portland cement pastes. These pastes were monitored for 1, 4, 8 h and 1, 2, 3, 7 and 28 curing days. In order to study the influence of the pozzolanic material (spent FCC catalyst), Portland cement replacements of 5, 15 and 30 % by mass were carried out. The presence of spent FCC catalyst in blended pastes modified the amount and the nature of the formed hydrates, mainly ettringite and stratlingite.

Use of spent compost in the cultivation of Agaricus blazei

Two compost formulations, based on Braquiaria straw (Brachiaria sp.), a conventional one and a spent one, were tested in the cultivation of ABL 99/30 and ABL 04/49 strains of Agaricus blazei. The experimental design was in a completely randomized factorial scheme with four treatments (two strains of A. blazei x two types of compost) and 30 repetitions. Each experimental unit consisted of a box with 10 to 10.5 kg of moist fresh compost. According to the results obtained, the loss of organic matter of the composts was affected by the A. blazei strain and the type of compost used. The traditional compost lost a higher organic matter content compared to the spent compost, and the ABL 99/30 strain caused a higher loss of organic matter in the composts compared to the ABL 04/49 strain. Yield, biological efficiency, mass and number of basidiomata produced were similar between the conventional and the spent compost, as well as the chemical analysis of the produced basidiomata. However, the A. blazei strains showed some differences among each other, the basidiomata of strain ABL 04/49 obtained a higher percentage of crude protein in their composition, compared to the ABL 99/30, in both composts. Thus, the utilization of spent compost in the cultivation of A. blazei did not impair the basidiomata yield nor their nutritional value, demonstrating it to be a good option to be used as an ingredient in the compost formulation for the A. blazei cultivation.

The implicit achievement motive and general life stress affect time spent on competitive matches in racquet sports

The match time spent on court in racquet sports can be perceived as dependent on the effort an athlete is willing to exert in a competition. Achievement motivation is defined as the effort a person spends on a difficult task with the completion of which she wants to meet a personal standard of excellence, wants to improve herself, or outperform others (McClelland, Atkinson, Clark, & Lowell, 1953). Fifty-two professionals of three racquet sports (tennis, table tennis, and badminton) filled in a questionnaire on their explicit achievement motive, a scale on general life stress, and a measure of the implicit achievement motive. Results indicate that the implicit but not the explicit achievement motive was able to predict the athletes' time spent on court (effort). Additionally the general life stress scale was negatively related to time spent on court. Findings are in line with theoretical assumptions that actual behavior is linked to the implicit achievement motive and that higher levels of general life stress lead to impaired performance in sports.

Eye movements discriminate fatigue due to chronotypical factors and time spent on task--a double dissociation

Systematic differences in circadian rhythmicity are thought to be a substantial factor determining inter-individual differences in fatigue and cognitive performance. The synchronicity effect (when time of testing coincides with the respective circadian peak period) seems to play an important role. Eye movements have been shown to be a reliable indicator of fatigue due to sleep deprivation or time spent on cognitive tasks. However, eye movements have not been used so far to investigate the circadian synchronicity effect and the resulting differences in fatigue. The aim of the present study was to assess how different oculomotor parameters in a free visual exploration task are influenced by: a) fatigue due to chronotypical factors (being a 'morning type' or an 'evening type'); b) fatigue due to the time spent on task. Eighteen healthy participants performed a free visual exploration task of naturalistic pictures while their eye movements were recorded. The task was performed twice, once at their optimal and once at their non-optimal time of the day. Moreover, participants rated their subjective fatigue. The non-optimal time of the day triggered a significant and stable increase in the mean visual fixation duration during the free visual exploration task for both chronotypes. The increase in the mean visual fixation duration correlated with the difference in subjectively perceived fatigue at optimal and non-optimal times of the day. Conversely, the mean saccadic speed significantly and progressively decreased throughout the duration of the task, but was not influenced by the optimal or non-optimal time of the day for both chronotypes. The results suggest that different oculomotor parameters are discriminative for fatigue due to different sources. A decrease in saccadic speed seems to reflect fatigue due to time spent on task, whereas an increase in mean fixation duration a lack of synchronicity between chronotype and time of the day.

Days spent in acute care hospitals at the end of life of cancer patients in four Swiss cantons: a retrospective database study (SAKK 89/09).

Number of days spent in acute hospitals (DAH) at the end of life is regarded as an important care quality indicator for cancer patients. We analysed DAH during 90 days prior to death in patients from four Swiss cantons. Claims data from an insurance provider with about 20% market share and patient record review identified 2086 patients as dying of cancer. We calculated total DAH per patient. Multivariable generalised linear modelling served to evaluate potential explanatory variables. Mean DAH was 26 days. In the multivariable model, using complementary and alternative medicine (DAH = 33.9; +8.8 days compared to non-users) and canton of residence (for patient receiving anti-cancer therapy, Zürich DAH = 22.8 versus Basel DAH = 31.4; for other patients, Valais DAH = 22.7 versus Ticino DAH = 33.7) had the strongest influence. Age at death and days spent in other institutions were additional significant predictors. DAH during the last 90 days of life of cancer patients from four Swiss cantons is high compared to most other countries. Several factors influence DAH. Resulting differences are likely to have financial impact, as DAH is a major cost driver for end-of-life care. Whether they are supply- or demand-driven and whether patients would prefer fewer days in hospital remains to be established.

The relationship between food preparation time, time spent grocery shopping, and BMI

Recent data have shown that the percentage of time spent preparing food has decreased during the past few years, and little information is know about how much time people spend grocery shopping. Food that is pre-prepared is often higher in calories and fat compared to foods prepared at home from scratch. It has been suggested that, because of the higher energy and total fat levels, increased consumption of pre-prepared foods compared to home-cooked meals can lead to weight gain, which in turn can lead to obesity. Nevertheless, to date no study has examined this relationship. The purpose of this study is to determine (i) the association between adult body mass index (BMI) and the time spent preparing meals, and (ii) the association between adult BMI and time spent shopping for food. Data on food habits and body size were collected with a self-report survey of ethnically diverse adults between the ages of 17 and 70 at a large university. The survey was used to recruit people to participate in nutrition or appetite studies. Among other data, the survey collected demographic data (gender, race/ethnicity), minutes per week spent in preparing meals and minutes per week spent grocery shopping. Height and weight were self-reported and used to calculate BMI. The study population consisted of 689 subjects, of which 276 were male and 413 were female. The mean age was 23.5 years, with a median age of 21 years. The fraction of subjects with BMI less than 24.9 was 65%, between 25 and 29.9 was 26%, and 30 or greater was 9%. Analysis of variation was used to examine associations between food preparation time and BMI. ^ The results of the study showed that there were no significant statistical association between adult healthy weight, overweight and obesity with either food preparation time and grocery shopping time. Of those in the sample who reported preparing food, the mean food preparation time per week for the healthy weight, overweight, and obese groups were 12.8 minutes, 12.3 minutes, and 11.6 minutes respectively. Similarly, the mean weekly grocery shopping for healthy, overweight, and obese groups were 60.3 minutes per week (8.6min./day), 61.4 minutes (8.8min./day), and 57.3 minutes (8.2min./day), respectively. Since this study was conducted through a University campus, it is assumed that most of the sample was students, and a percentage might have been utilizing meal plans on campus, and thus, would have reported little meal preparation or grocery shopping time. Further research should examine the relationships between meal preparation time and time spent shopping for food in a sample that is more representative of the general public. In addition, most people spent very little time preparing food, and thus, health promotion programs for this population need to focus on strategies for preparing quick meals or eating in restaurants/cafeterias. ^

Progress on spent fuel data compilations for PWRs

A “Collaborative Agreement” involving the collective participation of our students in their last year of our “Nuclear Engineering Master Degree Programme” for: “the review and capturing of selected spent fuel isotopic assay data sets to be included in the new SFCOMPO database"

Multiple removal of spent rocket upper stages with an ion beam shepherd

Among the many advantages of the recently proposed ion beam shepherd (IBS) debris removal technique is the capability to deal with multiple targets in a single mission. A preliminary analysis is here conducted in order to estimate the cost in terms of spacecraft mass and total mission time to remove multiple large-size upper stages of the Zenit family. Zenit-2 upper stages are clustered at 71 degrees inclination around 850 km altitude in low Earth orbit. It is found that a removal of two targets per year is feasible with a modest size spacecraft. The most favorable combinations of targets are outlined.