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121.
The Hazard analysis and critical control points (HACCP) is a preventive system which seeks to ensure food safety and security. It allows product protection and correction of errors, improves the costs derived from quality defects and reduces the final overcontrol. In this paper, the system is applied to the line of cultivation of mushrooms and other edible cultivated fungi. From all stages of the process, only the reception of covering materials (stage 1) and compost (stage 3), the pre-fruiting and induction (step 6) and the harvest (stage 7) have been considered as critical control point (CCP). The main hazards found were the presence of unauthorized phytosanitary products or above the permitted dose (stages 6 and 7), and the presence of pathogenic bacteria (stages 1 and 3) and/or heavy metals (stage 3). The implementation of this knowledge will allow the self-control of their productions based on the system HACCP to any plant dedicated to mushroom or other edible fungi cultivation.  相似文献   
122.
Arnar Árnason  Bob Simpson 《Ethnos》2013,78(4):533-553
This paper explores the processes whereby complex scientific developments are rendered into locally intelligible idioms as part of strategies to incorporate a ‘public’ in decisions which may have profound implications in the longer term. We focus in particular on the recent developments in genetic technologies and take as our example the deCode biogenetic project in Iceland. We trace how the images and metaphors drawn upon by all sides of the debate created powerful resonances with Icelandic history and culture. We analyse these representations and the broader themes of ethnicity and nationalism which they invoke.  相似文献   
123.
The small white‐marmorated longicorn beetle, Monochamus sutor (L.) (Coleoptera: Cerambycidae), is widely distributed throughout Europe and Asia. It is a potential vector of the pine wood nematode, Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle, the causal agent of the devastating pine wilt disease. Volatiles were collected from both male and female beetles after maturation feeding. In analyses of these collections using gas chromatography (GC) coupled to mass spectrometry, a single male‐specific compound was detected and identified as 2‐(undecyloxy)‐ethanol. In analyses by GC coupled to electroantennography the only consistent responses from both female and male antennae were to this compound. Trapping tests were carried out in Spain, Sweden, and China. 2‐(Undecyloxy)‐ethanol was attractive to both male and female M. sutor beetles. A blend of the bark beetle pheromones ipsenol, ipsdienol, and 2‐methyl‐3‐buten‐2‐ol was also attractive to both sexes in Spain and Sweden, and further increased the attractiveness of the 2‐(undecyloxy)‐ethanol. The host plant volatiles α‐pinene, 3‐carene, and ethanol were weakly attractive, if at all, in all three countries and did not significantly increase the attractiveness of the blend of 2‐(undecyloxy)‐ethanol and bark beetle pheromones. 2‐(Undecyloxy)‐ethanol is thus proposed to be the major, if not only, component of the male‐produced aggregation pheromone of M. sutor, and its role is discussed. This compound has been reported as a pheromone of several other Monochamus species and is another example of the parsimony that seems to exist among the pheromones of many of the Cerambycidae. Traps baited with 2‐(undecyloxy)‐ethanol and bark beetle pheromones should be useful for monitoring and control of pine wilt disease, should M. sutor be proven to be a vector of the nematode.  相似文献   
124.
Pollen grains of 30, mainly annual, species from 134 populations of the genus Veronica (Plantaginaceae, formerly Scrophulariaceae) from the Mediterranean Region, have been studied with light and scanning electron microscopy. Three pollen types are defined based on pollen size and exine surface sculpture. In some cases within the study group pollen size can be useful in species determination. Hypothetical relationships of pollen grain size and aperture number with ploidy level, style length and corolla diameter are discussed. The ornamentation of the exine in Veronica, although generally a conservative character within the genus, gives some additional support to the most recent infrageneric classification of Veronica.  相似文献   
125.
The ecology of macroinvertebrate communities in arid regions is still poorly understood. Here we examined how the community structure varied at spatial and temporal scales in streams and tributaries of the Huasco River in semi-arid region of Northern Chile. We expected that macroinvertebrate distribution may be responding to natural processes of mineralization described for Chilean semiarid basins. The relationships among biotic and abiotic variables were assessed through multivariate techniques (principal component analysis, non-metric multidimensional scaling, canonical correspondence analysis), and a two-way analysis of similarity was used to evaluate differences between basins and years (2007, 2008, and 2009). Significant differences in community structure and physical–chemical variables between basins (Del Carmen and Del Tránsito) were found, but not between years. Altitude, Mn, Al, Ca, Na, HCO3, and dissolved oxygen were the variables that best accounted for the communities distribution. In particular, high metals concentration in El Transito basin should determine low density and diversity of macroinvertebrates. Chironomidae, Ephydridae, and Glossiphoniidae were associated to waters with high metals content and acidic pH, whereas Baetidae, Hydroptilidae, and Blephariceridae were associated to sites with more favorable physical–chemical conditions. These results contribute to understand the ecological patterns of macroinvertebrates in arid regions and should lead to conservation and monitoring plans for this remote place.  相似文献   
126.
Methylation of histone arginine residues is an epigenetic mark related to gene expression that is implicated in a variety of biological processes and can be reversed by small-molecule modulators of protein arginine methyltransferases (PRMTs). A series of symmetrical ureas, designed as analogues of the known PRMT1 inhibitor AMI-1 have been synthesized using Pd-catalyzed Ar–N amide bond formation processes or carbonylation reactions as key steps. Their inhibitory profile has been characterized. The enzymatic assays showed a weak effect on PRMT1 and PRMT5 activity for most of the compounds. The acyclic urea that exhibited the strongest effect on the inhibition of the PRMT1 activity also showed the greatest effect on the expression of some androgen receptor target genes (TMPRSS2 and FKBP5), which may be related with its enzymatic activity. Surprisingly, AMI-1 behaved as an activator of PRMT5 activity, a result not reported so far.  相似文献   
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Genotype effects on lamb carcass traits were investigated in a 4-year study aimed at assessing potential benefits from introducing meat breeds into the wool-oriented extensive sheep systems of northeastern Patagonia, Argentina. Five ram [Corriedale: CO; Border Leicester: BL; Île de France: IF; Texel: TX; and synthetic CRIII (25% Merino, 37.5% IF, 37.5% TX)] and 5 dam (CO; synthetic CRIII; BLCO: BL × CO; IFCO: IF × CO; and TXCO: TX × CO) genotypes were represented in the study. Data were collected from 436 male lambs of 9 genotypes (CO × CO, BL × CO, IF × CO, TX × CO, CRIII × CO, CRIII × BLCO, CRIII × IFCO, CRIII × TXCO, and CRIII × CRIII). Hot carcass weights and dressing yields were determined after slaughtering. Carcasses were given conformation and subcutaneous fat scores using the EUROP system [scale varying from E (best) to P (poorest) for conformation, and from 1 (lean) to 5 (overfat) for subcutaneous fat]. Linear measurements of carcass length and width were recorded and carcass compactness indices were calculated from those. Purebred CO acted as a standard for comparisons. On a constant liveweight basis, genotypes CRIII × IFCO and CRIII × CRIII presented higher (P < 0.05) carcass weight and dressing yield than CO × CO and BL × CO. Crossbred and synthetic genotypes showed higher (P < 0.05) carcass width than CO × CO. With the exception of BL × CO the remaining genotypes showed higher (P < 0.05) carcass width/length ratio than CO × CO. The probability that carcasses of crossbred and synthetic lambs presented better conformation than CO × CO was higher than 84%. Carcasses of CRIII × IFCO lambs were given the best conformation scores. The probability that BL × CO carcasses presented higher subcutaneous fat than the remaining genotypes exceeded 79%. Our results indicate significant improvements in carcass conformation arising from crossing. Sheep farmers in extensive systems could take advantage of the higher fatness of BL crossbred lambs to produce light carcasses with adequate fat cover, a crucial industry requirement. Terminal crossbreeding with Île de France, Texel, and CRIII rams could be implemented to improve carcass conformation thus matching market demand for heavy carcasses with limited fat content. Second cross schemes did not improve carcass commercial traits over the best terminal cross or the synthetic CRIII breed.  相似文献   
130.
Recurring sequences of neuronal activation in the hippocampus are a candidate for a neurophysiological correlate of episodic memory. Here, we discuss a mean-field theory for such spike sequences in phase space and show how they become unstable when the neuronal network operates at maximum memory capacity. We find that inhibitory feedback rescues replay of the sequences, giving rise to oscillations and thereby enhancing the network’s capacity. We further argue that transient sequences in an overloaded network with feedback inhibition may provide a mechanistic picture of memory-related neuronal activity during hippocampal sharp-wave ripple complexes.  相似文献   
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