888 resultados para Security in the agricultural work


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Electromagnetic coupling phenomena between overhead power transmission lines and other nearby structures are inevitable, especially in densely populated areas. The undesired effects resulting from this proximity are manifold and range from the establishment of hazardous potentials to the outbreak of alternate current corrosion phenomena. The study of this class of problems is necessary for ensuring security in the vicinities of the interaction zone and also to preserve the integrity of the equipment and of the devices there present. However, the complete modeling of this type of application requires the three- -dimensional representation of the region of interest and needs specific numerical methods for field computation. In this work, the modeling of problems arising from the flow of electrical currents in the ground (the so-called conductive coupling) will be addressed with the finite element method. Those resulting from the time variation of the electromagnetic fields (the so-called inductive coupling) will be considered as well, and they will be treated with the generalized PEEC (Partial Element Equivalent Circuit) method. More specifically, a special boundary condition on the electric potential is proposed for truncating the computational domain in the finite element analysis of conductive coupling problems, and a complete PEEC formulation for modeling inductive coupling problems is presented. Test configurations of increasing complexities are considered for validating the foregoing approaches. These works aim to provide a contribution to the modeling of this class of problems, which tend to become common with the expansion of power grids.

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This paper provides an overview and comparison of labour markets in agricultural and rural areas in the three candidate countries for the EU membership: Croatia, the Former Yugoslav Republic of Macedonia and Turkey. We analyse and compare the labour market structures and the factors driving them. The analyses are based on the available cross-section and time-series data on agricultural labour structures and living conditions in rural areas. Considerable differences are found among the candidate countries in the importance of the agricultural labour force, between rural and urban labour, and in poverty and living conditions in rural areas. Agricultural and rural labour market structures are the result of demographic and education processes, in addition to labour flows between agricultural and non-agricultural activities, from rural areas to urban ones and migration flows abroad. Declines in the agricultural labour force and rural population are foreseen for each of the candidate countries, but with significant variations between them. Showing different patterns over time, labour market developments in the sector and rural areas have been shaped by the overall labour market institutions, conditions and other factors in each country, such as the legal basis, educational attainment and migration flows, as well as the presence of non-agricultural activities in rural areas.

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Climate change will exacerbate challenges facing food security in the UK. Increasing frequency and intensity of extreme weather events will further impact upon farm systems. At the heart of the impending challenges to UK agricultural production, farmers’ resilience will be tested to new limits. Research into farmers’ resilience to climate change in the UK is distinctly underdeveloped when compared to research in developing and other developed nations. This research gap is addressed through exploration of farmers’ resilience in the Welsh Marches, establishing the role of risk perceptions, local knowledge and adaptive capacity in farmers’ decision-making to limit climate shocks. Further contributions to agricultural geography are made through experimentation of a ‘cultural-behavioural approach’, seeking to revisit the behavioural approach in view of the cultural-turn. The Welsh Marches, situated on the English-Welsh border, has been selected as a focal point due to its agricultural diversity, and known experiences of extreme weather events. A phased mixed methodological approach is adopted. Phase one explores recorded and reported experiences of past extreme weather events in local meteorological records and local newspaper articles. Phase two consists of 115 survey-questionnaires, 15 in-depth semi-structured interviews, and a scenario based focus group with selected farmers from the Welsh Marches. This allows farmers’ resilience to climate change in the past, present and future to be explored. Original contributions to knowledge are made through demonstrating the value of focusing upon the culture of a specific farm community, applying a ‘bottom-up’ approach. The priority given to the weather in farmers’ decision-making is identified to be determined by individual relationships that farmers’ develop with the weather. Yet, a consensus of farmers’ observations has established recognition of considerable changes in the weather over the last 30 years, acknowledging more extremes and seasonal variations. In contrast, perceptions of future climate change are largely varied. Farmers are found to be disengaged with the communication of climate change science, as the global impacts portrayed are distant in time and place from probable impacts that may be experienced locally. Current communication of climate change information has been identified to alienate farmers from the local reality of probable future impacts. Adaptation options and responses to extreme weather and climate change are identified from measures found to be already implemented and considered for the future. A greater need to explore local knowledge and risk perception in relation to farmers’ understanding of future climate challenges is clear. There is a need to conduct comparable research in different farm communities across the UK. Progression into establishing the role of farmers’ resilience in responding effectively to future climate challenges has only just begun.

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Malaria remains a serious public health challenge in the tropical world, with 584,000 deaths globally in 2013, of which 90% occurred in Africa, and mostly in pregnant women and children under the age of five. Anopheles gambiae (An. gambiae) is the principal malaria vector in Africa, where vector control measures involve the use of insecticides in the forms of long-lasting insecticide-treated nets (LLINs) and indoor residual spraying (IRS). The development of insecticides resistance mitigates these approaches. Glutathione (GSH) is widely distributed among all living organisms, and is associated with detoxification pathways, especially the Glutathione S-transferases (GSTs). Its direct involvement and relevance in insecticide resistance in An. gambiae has not been determined. Thus, this work examines the contribution of GSH, its biosynthetic genes (GCLM, GCLC) and their possible transcriptional regulator Nrf2 in insecticide resistance in An. gambiae sampled from agricultural setting (areas of intensive agriculture) and residential setting (domestic area). Bioinformatics analysis, W.H.O. adult susceptibility bioassays and molecular techniques were employed to investigate. Total RNA was first isolated from the adults An. gambiae mosquitoes raised from agricultural and residential field-caught larvae which had been either challenged or unchallenged with insecticides. Semi-quantitative RT-PCR using gel image densitometry was used to determine the expression levels of GCLM, GCLC genes and Nrf2. Bioinformatics’ results established the presence of putative AGAP010259 (AhR) and AGAP005300 (Nf2e1) transcription factor binding sites in An. gambiae GCLC and GCLM promoters in silico. An. gambiae s.l. studied here were highly resistant to DDT and permethrin but less resistant to bendiocarb. Both knockdown resistance (kdr) mutation variants L1014S and L1014F that confers resistance to pyrethroid insecticides were identified in both An. coluzzii and An. arabiensis sampled from northern Nigeria. The L1014F was much associated with An. coluzzii. A significant positive correlation (P=0.04) between the frequency of the L1014F point mutation and resistance to DDT and permethrin was observed. However, a weak or non-significant correlation (P=0.772) between the frequency of the L1014S point mutation and resistance was also found. L1014S and L1014F mutations co-occurred in both agricultural and residential settings with high frequencies. However, the frequencies of the two mutations were greater in the agricultural settings than in the residential settings. The levels of total, reduced and oxidized GSH were significantly higher in mosquitoes from agricultural sites than those from residential sites. Increased oxidized GSH levels appears to correlate with higher DDT resistance. The expression levels of GCLM, GCLC and Nrf2 were also significantly up-regulated in adults An. gambiae raised from agricultural and residential field-caught larvae when challenged with insecticide. However, there was higher constitutive expression of GCLM, GCLC and Nrf2 in mosquitoes from agricultural setting. The increased expression levels of these genes and also GSH levels in this population suggest their roles in the response and adaptation of An. gambiae to insecticide challenges. There exists the feasibility of using GSH status in An. gambiae to monitor adaptation and resistance to insecticides.

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The traditional process of filling the medicine trays and dispensing the medicines to the patients in the hospitals is manually done by reading the printed paper medicinechart. This process can be very strenuous and error-prone, given the number of sub-tasksinvolved in the entire workflow and the dynamic nature of the work environment.Therefore, efforts are being made to digitalise the medication dispensation process byintroducing a mobile application called Smart Dosing application. The introduction ofthe Smart Dosing application into hospital workflow raises security concerns and callsfor security requirement analysis. This thesis is written as a part of the smart medication management project at EmbeddedSystems Laboratory, A˚bo Akademi University. The project aims at digitising the medicine dispensation process by integrating information from various health systems, and making them available through the Smart Dosing application. This application is intended to be used on a tablet computer which will be incorporated on the medicine tray. The smart medication management system include the medicine tray, the tablet device, and the medicine cups with the cup holders. Introducing the Smart Dosing application should not interfere with the existing process carried out by the nurses, and it should result in minimum modifications to the tray design and the workflow. The re-designing of the tray would include integrating the device running the application into the tray in a manner that the users find it convenient and make less errors while using it. The main objective of this thesis is to enhance the security of the hospital medicine dispensation process by ensuring the security of the Smart Dosing application at various levels. The methods used for writing this thesis was to analyse how the tray design, and the application user interface design can help prevent errors and what secure technology choices have to be made before starting the development of the next prototype of the Smart Dosing application. The thesis first understands the context of the use of the application, the end-users and their needs, and the errors made in everyday medication dispensation workflow by continuous discussions with the nursing researchers. The thesis then gains insight to the vulnerabilities, threats and risks of using mobile application in hospital medication dispensation process. The resulting list of security requirements was made by analysing the previously built prototype of the Smart Dosing application, continuous interactive discussions with the nursing researchers, and an exhaustive state-of-the-art study on security risks of using mobile applications in hospital context. The thesis also uses Octave Allegro method to make the readers understand the likelihood and impact of threats, and what steps should be taken to prevent or fix them. The security requirements obtained, as a result, are a starting point for the developers of the next iteration of the prototype for the Smart Dosing application.

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The electrocardiogram (ECG) is the simplest and most effective non-invasive method to assess the electrical activity of the heart and to obtain information on the heart rate (HR) and rhythm. Because information on the HR of very small reptiles (body mass <10 g) is still scarce in the literature, in the present work we describe a procedure for recording the ECG in non-anesthetized geckos (Hemidactylus mabouia, Moreau de Jonnès, 1818) under different conditions, namely manual restraint (MR), spontaneous tonic immobility (TI), and in the non-restrained condition (NR). In the gecko ECG, the P, QRS and T waves were clearly distinguishable. The HR was 2.83 ± 0.02 Hz under MR, which was significantly greater (p < 0.001) than the HR under the TI (1.65 ± 0.09 Hz) and NR (1.60 ± 0.10 Hz) conditions. Spontaneously beating isolated gecko hearts contracted at 0.84 ± 0.03 Hz. The in vitro beating rate was affected in a concentration-dependent fashion by adrenoceptor stimulation with noradrenaline, as well as by the muscarinic cholinergic agonist carbachol, which produced significant positive and negative chronotropic effects, respectively (p < 0.001). To our knowledge, this is the first report on the ECG morphology and HR values in geckos, particularly under TI. The methodology and instrumentation developed here are useful for non-invasive in vivo physiological and pharmacological studies in small reptiles without the need of physical restraint or anesthesia.

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Echinolaena inflexa (Poir.) Chase is an abundant C3 grass species with high biomass production in the Brazilian savanna (cerrado); Melinis minutiflora Beauv. is an African C4 forage grass widespread in cerrado and probably displacing some native herbaceous species. In the present work, we analysed seasonally the content and composition of soluble carbohydrates, the starch amounts and the above-ground biomass (phytomass) of E. inflexa and M. minutiflora plants harvested in two transects at 5 and 130 m from the border in a restrict area of cerrado at the Biological Reserve and Experimental Station of Mogi-Guaçu (SP, Brazil). Results showed that water soluble carbohydrates and starch amounts from the shoots of both species varied according to the time of the year, whilst in the underground organs, variations were observed mainly in relation to the transects. Marked differences in the pattern of the above-ground biomass production between these two grasses relative to their location in the Reserve were also observed, with two peaks of the invasive species (July and January) at the Reserve border. The differences in carbohydrate accumulation, partitioning and composition of individual sugars concerning time of the year and location in the Reserve were more related to the annual growth cycle of both grasses and possibly to specific physiological responses of M. minutiflora to disturbed environments in the Reserve border.

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A new criterion has been recently proposed combining the topological instability (lambda criterion) and the average electronegativity difference (Delta e) among the elements of an alloy to predict and select new glass-forming compositions. In the present work, this criterion (lambda.Delta e) is applied to the Al-Ni-La and Al-Ni-Gd ternary systems and its predictability is validated using literature data for both systems and additionally, using own experimental data for the Al-La-Ni system. The compositions with a high lambda.Delta e value found in each ternary system exhibit a very good correlation with the glass-forming ability of different alloys as indicated by their supercooled liquid regions (Delta T(x)) and their critical casting thicknesses. In the case of the Al-La-Ni system, the alloy with the largest lambda.Delta e value, La(56)Al(26.5)Ni(17.5), exhibits the highest glass-forming ability verified for this system. Therefore, the combined lambda.Delta e criterion is a simple and efficient tool to select new glass-forming compositions in Al-Ni-RE systems. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3563099]

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Background: In spite of its advantageous physiological properties for bioprocess applications, the use of the yeast Kluyveromyces marxianus as a host for heterologous protein production has been very limited, in constrast to its close relative Kluyveromyces lactis. In the present work, the model protein glucose oxidase (GOX) from Aspergillus niger was cloned into K. marxianus CBS 6556 and into K. lactis CBS 2359 using three different expression systems. We aimed at verifying how each expression system would affect protein expression, secretion/localization, post-translational modification, and biochemical properties. Results: The highest GOX expression levels (1552 units of secreted protein per gram dry cell weight) were achieved using an episomal system, in which the INU1 promoter and terminator were used to drive heterologous gene expression, together with the INU1 prepro sequence, which was employed to drive secretion of the enzyme. In all cases, GOX was mainly secreted, remaining either in the periplasmic space or in the culture supernatant. Whereas the use of genetic elements from Saccharomyces cerevisiae to drive heterologous protein expression led to higher expression levels in K. lactis than in K. marxianus, the use of INU1 genetic elements clearly led to the opposite result. The biochemical characterization of GOX confirmed the correct expression of the protein and showed that K. marxianus has a tendency to hyperglycosylate the protein, in a similar way as already observed for other yeasts, although this tendency seems to be smaller than the one of e. g. K. lactis and S. cerevisiae. Hyperglycosylation of GOX does not seem to affect its affinity for the substrate, nor its activity. Conclusions: Taken together, our results indicate that K. marxianus is indeed a good host for the expression of heterologous proteins, not only for its physiological properties, but also because it correctly secretes and folds these proteins.

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Galectin-3 is a beta-galactoside-binding protein that has been shown to regulate pathophysiological processes, including cellular activation, differentiation and apoptosis. Recently, we showed that galectin-3 acts as a potent inhibitor of B cell differentiation into plasma cells. Here, we have investigated whether galectin-3 interferes with the lymphoid organization of B cell compartments in mesenteric lymph nodes (MLNs) during chronic schistosomiasis, using WT and galectin-3(-/-) mice. Schistosoma mansoni synthesizes GalNAc beta 1-4(Fuc alpha 1-3) GlcNAc(Lac-DiNAc) structures (N-acetylgalactosamine beta 1-4 N-acetylglucosamine), which are known to interact with galectin-3 and elicit an intense humoral response. Antigens derived from the eggs and adult worms are continuously drained to MLNs and induce a polyclonal B cell activation. In the present work, we observed that chronically-infected galectin-3(-/-) mice exhibited a significant reduced amount of macrophages and B lymphocytes followed by drastic histological changes in B lymphocyte and plasma cell niches in the MLNs. The lack of galectin-3 favored an increase in the lymphoid follicle number, but made follicular cells more susceptible to apoptotic stimuli. There were an excessive quantity of apoptotic bodies, higher number of annexin V(+)/PI(-) cells, and reduced clearance of follicular apoptotic cells in the course of schistosomiasis. Here, we observed that galectin-3 was expressed in nonlymphoid follicular cells and its absence was associated with severe damage to tissue architecture. Thus, we convey new information on the role of galectin-3 in regulation of histological events associated with B lymphocyte and plasma cell niches, apoptosis, phagocytosis and cell cycle properties in the MLNs of mice challenged with S. mansoni.

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We derive a closed form expression for the sum of all the infrared divergent contributions to the free energy of a gas of gravitons. An important ingredient of our calculation is the use of a gauge fixing procedure such that the graviton propagator becomes both traceless and transverse. This has been shown to be possible, in a previous work, using a general gauge fixing procedure, in the context of the lowest order expansion of the Einstein-Hilbert action, describing noninteracting spin-two fields. In order to encompass the problems involving thermal loops, such as the resummation of the free energy, in the present work, we have extended this procedure to the situations when the interactions are taken into account.

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Since it was trapped in the XIX(th) century, Rhagomys rufescens has been considered a rare endangered sigmodontine rodent and an endemic species of the Atlantic forest. Only a handful of vouchers of this taxon were known by Thomas, 1886. Recently, eight new individuals were collected, providing new geographical, morphological and phylogenetic (based on molecular evidence) information on this species. In the present work we report the southernmost occurrence record for R. rufescens at Indaial, Santa Catarina State, with the largest collected series of this species, the northernmost occurrence record at Santa Teresa, Espirito Santo State, and new records from Pocos de Caldas, Minas Gerais State, from Ibiuna and Ribeirao Grande, Sao Paulo State.

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The rhizosphere is an ecosystem exploited by a variety of organisms involved in plant health and environmental sustainability. Abiotic factors influence microorganism-plant interactions, but the microbial community is also affected by expression of heterologous genes from host plants. In the present work, we assessed the community shifts of Alphaproteobacteria phylogenetically related to the Rhizobiales order (Rhizobiales-like community) in rhizoplane and rhizosphere soils of wild-type and transgenic eucalyptus. A greenhouse experiment was performed and the bacterial communities associated with two wild-type (WT17 and WT18) and four transgenic (TR-9, TR-15, TR-22, and TR-23) eucalyptus plant lines were evaluated. The culture-independent approach consisted of the quantification, by real-time polymerase chain reaction (PCR), of a targeted subset of Alphaproteobacteria and the assessment of its diversity using PCR-denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone libraries. Real-time quantification revealed a lesser density of the targeted community in TR-9 and TR-15 plants and diversity analysis by principal components analysis, based on PCR-DGGE, revealed differences between bacterial communities, not only between transgenic and nontransgenic plants, but also among wild-type plants. The comparison between clone libraries obtained from the transgenic plant TR-15 and wild-type WT17 revealed distinct bacterial communities associated with these plants. In addition, a culturable approach was used to quantify the Methylobacterium spp. in the samples where the identification of isolates, based on 16S rRNA gene sequences, showed similarities to the species Methylobacterium nodulans, Methylobacterium isbiliense, Methylobacterium variable, Methylobacterium fujisawaense, and Methylobacterium radiotolerans. Colonies classified into this genus were not isolated from the rhizosphere but brought in culture from rhizoplane samples, except for one line of the transgenic plants (TR-15). In general, the data suggested that, in most cases, shifts in bacterial communities due to cultivation of transgenic plants are similar to those observed when different wild-type cultivars are compared, although shifts directly correlated to transgenic plant cultivation may be found.

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Pharmaceuticals can exist in many solid forms, which can have different physical and chemical properties. These solid forms include polymorphs, solvates, amorphous, and hydrates. Particularly, hydration process can be quite common since pharmaceutical solids can be in contact with water during manufacturing process and can also be exposed to water during storage. In the present work, it is proved that NQR technique is capable of detecting different hydrated forms not only in the pure raw material but also in the final product (tablets), being in this way a useful technique for quality control. This technique was also used to study the dehydration process from pentahydrate to trihydrate.

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The lateral septal area (LSA) is a part of the limbic system and is involved in cardiovascular modulation. We previously reported that microinjection of noradrenaline (NA) into the LSA of unanesthetized rats caused pressor responses that are mediated by acute vasopressin release. Magnocellular neurons of the paraventricular (PVN) and supraoptic (SON) of the hypothalamus synthesize vasopressin. In the present work, we studied which of these nuclei is involved in the pressor pathway activated by unilateral NA injection into the LSA as well as the local neurotransmitter involved. Chemical ablation of the SON by unilateral injection of the nonspecific synapses blocker cobalt chloride (1 mM/100 nl) did not affect the pressor response evoked by NA (21 nmol/200 nl) microinjection into the LSA. However, the response to NA was blocked when cobalt chloride (1 mM/100 nl) was microinjected into the PVN, indicating that this hypothalamic nucleus is responsible for the mediation of the pressor response. There is evidence in the literature pointing to glutamate as a putative neurotransmitter activating magnocellular neurons. Pretreatment of the PVN with the selective non-N-methyl-D-asparate (NMDA) antagonist NBQX (2 nmol/100 nl) blocked the pressor response to NA microinjected into the LSA, whereas pretreatment with the selective NMDA antagonist LY235959 (2 nmol/100 nl) did not affect the response to NA. Our results implicate the PVN as the final structure in the pressor pathway activated by the microinjection of NA into the LSA. They also indicate that local glutamatergic synapses and non-NMDA glutamatergic receptors mediate the response in the PVN. (c) 2008 Wiley-Liss, Inc.