New routes for the field trip

As with the broader field of education research, most writing on the subject of school excursions and field trips has centred around progressive/humanist concerns for building pupil’s self-esteem and for the development of the ‘whole child’. Such research has also stressed the importance of a broad, grounded, and experiential curriculum - as exemplified by subjects containing these extra-school activities - as well as the possibility of strengthening the relationship between student and teacher. Arguing that this approach to the field trip is both exhausted of ideas and conceptually flawed, this paper proposes some alternate routes into the area for the prospective researcher. First, it is argued that by historicising the subject matter, it can be seen that school excursions are not simply the product of the contemporary humanist desire for diverse and fulfilling educational experiences, rather they can, in part, be traced to eighteenth century beliefs among the English gentry that travel formed a crucial component of a good education, to the advent of an affordable public rail system, and to school tours associated with the Temperance movement. Second, field trips can be understood from within the associated framework of concerns over the governance of tourism and the organisation of disciplinary apparatuses for the production of an educated and regulated citizenry. Far from being a simple learning experience, museums and art galleries form part of a complex of disciplinary and power relations designed to produce a populace with very specific capacities, aspirations and styles of public conduct. Finally, rather than allowing children ‘freedom’ from the constraints of the classroom, on the contrary, through the medium of the field-trip, children can become accustomed to having their activities governed in the broader domain of the generalised community . School excursions thereby constitute an effective tactic through which young people have their conduct managed, and their social and scholastic identities shaped and administered.

Automation of underground LHD and truck haulage

This paper reviews the state-of-the-art in the automation of underground mining vehicles and reports on the development of an autonomous navigation system under development through the CMTE with sponsorship arranged by AMIRA. Past attempts at automating LHDs and haul trucks are described and their particular strengths and weaknesses are discussed. The auto-guidance system being developed overcomes some of the limitations of state-of-the-art prototype æcommercialÆ systems. It can be retrofitted to existing remote controlled vehicles, uses minimum installed infrastructure and is flexible enough for rapid relocation to alternate routes. The navigation techniques use data fusion of two separate sets of sensors combining natural feature recognition, nodal maps and inertial navigation techniques. Collision detection is incorporated and people and other traffic are excluded from the tramming area. This paper describes the work being done by the group with regard to auto-tramming and also outlines the future goals.

Design normal: memória e invisibilidade dos objectos

As últimas décadas têm sido caracterizadas por uma crescente indefinição do design, que refletindo um dia-a-dia cada vez mais complexo, não pode mais ser encarado como actividade fechada no projecto e acabada no produto. O seu universo aumentou e dispersou-se em mercados menores, alargando o seu alcance e sua importância, transformando-o em termo quantitativo e inflacionário. A crescente atenção de que é alvo dramatizou a sua relação com o consumo, o ruído nas prateleiras e a superficialidade da generalização de uma perspectiva do projecto focada nos new media, validando uma abordagem narcisista e de dispensa do diálogo com a indústria, tornaram-no sinónimo de especial. Este trabalho procura confirmar e refletir sobre a existência de um universo de produtos concretos e abordagens que de forma consciente partilham esta noção do contexto actual, em primeiro lugar, sugerindo caminhos alternativos e reacções resultantes da prática e discurso. Em segundo lugar procura analisar se tal reacção pode ser considerada como um movimento. Partindo de uma revisão bibliográfica, e de uma reflexão sobre um universo de produtos do dia-a-dia, procura-se, em terceiro lugar, interpretar e organizar as diversas formas e estratégias de rejeição da noção de design especial. Da procura de abordagens opostas a especial resulta uma ideia base de normal, normal sem ser banal, expressa na exposição Super Normal. Da extensão a um universo maior de produtos, reacções e autores, resulta a ideia de normal como um conceito mais abrangente, mas composto por conceitos menores, mais específicos, mais concretos e fáceis de identificar nos objectos. A organização e interpretação dessas abordagens resulta num triângulo de conceitos que constroem a noção de normal pela procura da evolução por recurso à memória e ao conhecimento, da invisibilidade pela integração e diluição do produto e projecto, e da liberdade como meio de adequação ao contexto actual. O livro resultante reflete uma abordagem definida de uma época, e não todo o panorama. A sistematização do conceito de normal a partir da segmentação em ideias menores, mais concretas e identificáveis nos produtos, procura proporcionar a consulta organizada de reacções ao contexto dominante actual, à ideia de especial, mas mais do que regras, procura fornecer um documento de reflexão a visitar no acto de projectar, seja como um todo, ou em partes.

Toxicological and histopathological effects of hydramethylnon on Atta sexdens rubropilosa (Hymenoptera: Formicidae) workers

The leaf-cut ants are important agricultural pest, because they can cause intense defoliation in plants and destroy large areas cultivated. Although there are several works for the control of these insects by examining the toxicity of natural chemical compounds on various species of ants, few are focused on analyses of morphological changes caused in the affected organs. The aim of this study was to evaluate the effects of hydramethylnon on Atta sexdens rubropilosa workers through toxicological bioassays and morphological analysis of the post-pharyngeal glands, midgut, and Malpighian tubules of these ants. Hydramethylnon dissolved either in acetone (HA) or in a mixture of acetone and soy oil (HAO) was added to the artificial diet at a concentration of 200 μg/mL. The workers fed daily with the diet containing hydramethylnon showed higher mortality than the controls, especially when HAO was used. Moreover, light and electron microscopy revealed morphological alterations in the midgut and Malpighian tubules of workers treated with HA, whereas alterations of the post-pharyngeal glands were observed in the HAO-treated group. These results indicated that the presence of soy oil provided an alternate route for the ingestion of the formicide's active ingredient and corroborated previous studies that suggested a role for the post-pharyngeal glands in lipid metabolism. Our findings suggest that the oil may carry hydramethylnon to the gland lumen, resulting in lower quantity of the active ingredient in the intestinal lumen and Malpighian tubules that explains the lower degree of morphological alterations in these structures in the workers treated with HAO. These results may provide insight into the toxicological effects of hydramethylnon on leaf-cutting ants and the use of vegetable oil as an adjuvant in baits to control ants. © 2012 Elsevier Ltd.

Identification and localization of polyketide synthase genes from cultures of diarrheic shellfish poisoning toxin producing dinoflagellates of the genus Prorocentrum

Aquatic toxins are responsible for a number of acute and chronic diseases in humans. Okadaic acid (OA) and other dinoflagellate derived polyketide toxins pose serious health risks on a global scale. Ingestion of OA contaminated shellfish causes diarrheic shellfish poisoning (DSP). Some evidence also suggests tumor promotion in the liver by OA. Microcystin-LR (MC-LR) is produced by cyanobacteria and is believed to be the most common freshwater toxin in the US. Humans may be exposed to this acute hepatotoxin through drinking or recreational use of contaminated waters. ^ OA producing dinoflagellates have not been cultured axenically. The presence of associated bacteria raises questions about the ultimate source of OA. Identification of the toxin-producing organism(s) is the first step in identifying the biosynthetic pathways involved in toxin production. Polyketide synthase (PKS) genes of toxic and non-toxic species were surveyed by construction of clonal libraries from PCR amplicons of various toxic and non-toxic species of Prorocentrum in an effort to identify genes, which may be part of the biosynthetic pathway of OA. Analysis of the PKS sequences revealed that toxic species shared identical PKS genes not present in non-toxic species. Interestingly, the same PKS genes were identified in a library constructed from associated bacteria. ^ Subsequent bacterial small subunit RNA (16S) clonal libraries identified several common bacterial species. The most frequent 16S sequences found were identified as species of the genus Roseobacter which has previously been implicated in the production of OA. Attempts to culture commonly occurring bacteria resulted in the isolation of Oceanicaulis alexandrii , a novel marine bacterium previously isolated from the dinoflagellate Alexandrium tamarense, from both P. lima, and P. hoffmanianum. ^ Metabolic studies of microcystin-LR, were conducted to probe the activity of the major human liver cytochromes (CYP) towards the toxin. CYPs may provide alternate routes of detoxification of toxins when the usual routes have been inhibited. For example, some research indicates that cyanobacterial xenobiotics, in particular, lipopolysaccharides may inhibit glutathione S-transferases allowing the toxin to persist long enough to be acted upon by other enzymes. These studies found that at least one human liver CYP was capable of metabolizing the toxin. ^

Predicting delay reductions from freeway traffic diversion for incident management

Traffic incidents are a major source of traffic congestion on freeways. Freeway traffic diversion using pre-planned alternate routes has been used as a strategy to reduce traffic delays due to major traffic incidents. However, it is not always beneficial to divert traffic when an incident occurs. Route diversion may adversely impact traffic on the alternate routes and may not result in an overall benefit. This dissertation research attempts to apply Artificial Neural Network (ANN) and Support Vector Regression (SVR) techniques to predict the percent of delay reduction from route diversion to help determine whether traffic should be diverted under given conditions. The DYNASMART-P mesoscopic traffic simulation model was applied to generate simulated data that were used to develop the ANN and SVR models. A sample network that comes with the DYNASMART-P package was used as the base simulation network. A combination of different levels of incident duration, capacity lost, percent of drivers diverted, VMS (variable message sign) messaging duration, and network congestion was simulated to represent different incident scenarios. The resulting percent of delay reduction, average speed, and queue length from each scenario were extracted from the simulation output. The ANN and SVR models were then calibrated for percent of delay reduction as a function of all of the simulated input and output variables. The results show that both the calibrated ANN and SVR models, when applied to the same location used to generate the calibration data, were able to predict delay reduction with a relatively high accuracy in terms of mean square error (MSE) and regression correlation. It was also found that the performance of the ANN model was superior to that of the SVR model. Likewise, when the models were applied to a new location, only the ANN model could produce comparatively good delay reduction predictions under high network congestion level.

Predicting delay reductions from freeway traffic diversion for incident management

Traffic incidents are a major source of traffic congestion on freeways. Freeway traffic diversion using pre-planned alternate routes has been used as a strategy to reduce traffic delays due to major traffic incidents. However, it is not always beneficial to divert traffic when an incident occurs. Route diversion may adversely impact traffic on the alternate routes and may not result in an overall benefit. This dissertation research attempts to apply Artificial Neural Network (ANN) and Support Vector Regression (SVR) techniques to predict the percent of delay reduction from route diversion to help determine whether traffic should be diverted under given conditions. The DYNASMART-P mesoscopic traffic simulation model was applied to generate simulated data that were used to develop the ANN and SVR models. A sample network that comes with the DYNASMART-P package was used as the base simulation network. A combination of different levels of incident duration, capacity lost, percent of drivers diverted, VMS (variable message sign) messaging duration, and network congestion was simulated to represent different incident scenarios. The resulting percent of delay reduction, average speed, and queue length from each scenario were extracted from the simulation output. The ANN and SVR models were then calibrated for percent of delay reduction as a function of all of the simulated input and output variables. The results show that both the calibrated ANN and SVR models, when applied to the same location used to generate the calibration data, were able to predict delay reduction with a relatively high accuracy in terms of mean square error (MSE) and regression correlation. It was also found that the performance of the ANN model was superior to that of the SVR model. Likewise, when the models were applied to a new location, only the ANN model could produce comparatively good delay reduction predictions under high network congestion level.

Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic condition are Adapis parisiensis with a reduced promontorial canal, and Rooneyia and Mahgarita with reduced stapedial canals.

Alternate pathways of the early secretory route in yeast

The diversity of functions of eukaryotic cells is preserved by enclosing different enzymatic activities into membrane-bound organelles. Separation of exocytic proteins from those which remain in the endoplasmic reticulum (ER) casts the foundation for correct compartmentalization. The secretory pathway, starting from the ER membrane, operates by the aid of cytosolic coat proteins (COPs). In anterograde transport, polymerization of the COPII coat on the ER membrane is essential for the ER exit of proteins. Polymerization of the COPI coatomer on the cis-Golgi membrane functions for the retrieval of proteins from the Golgi for repeated use in the ER. The COPII coat is formed by essential proteins; Sec13/31p and Sec23/24p have been thought to be indispensable for the ER exit of all exocytic proteins. However, we found that functional Sec13p was not required for the ER exit of yeast endogenous glycoprotein Hsp150 in the yeast Saccharomyces cerevisiae. Hsp150 turned out to be an ATP phosphatase. ATP hydrolysis by a Walker motif located in the C-terminal domain of Hsp150 was an active mediator for the Sec13p and Sec24p independent ER exit. Our results suggest that in yeast cells a fast track transport route operates in parallel with the previously described cisternal maturation route of the Golgi. The fast track is used by Hsp150 with the aid of its C-terminal ATPase activity at the ER-exit. Hsp150 is matured with a half time of less than one minute. The cisternal maturation track is several-fold slower and used by other exocytic proteins studied so far. Operative COPI coat is needed for ER exit by a subset of proteins but not by Hsp150. We located a second active determinant to the Hsp150 polypeptide s N-terminal portion that guided also heterologous fusion proteins out of the ER in COPII coated vesicles under non-functional COPI conditions for several hours. Our data indicate that ER exit is a selective, receptor-mediated event, not a bulk flow. Furthermore, it suggests the existence of another retrieval pathway for essential reusable components, besides the COPI-operated retrotransport route. Additional experiments suggest that activation of the COPI primer, ADP ribosylation factor (ARF), is essential also for Hsp150 transport. Moreover, it seemed that a subset of proteins directly needed activated ARF in the anterograde transport to complete the ER exit. Our results indicate that coat structures and transport routes are more variable than it has been imagined.

The effect of alternate supply of shielding gases in austenite stainless steel GTA welding

Welding system has now been concentrated on the development of new process to achieve cost savings, higher productivity and better quality in manufacturing industry. Discrete alternate supply of shielding gas is a new technology that alternately supplies the different kinds of shielding gases in weld zone. As the newdevelopedmethods compared to the previous generalwelding with a mixing supply of shielding gas, it cannot only increase thewelding quality, but also reduce the energy by 20% and the emission rate of fume. As a result, under thesamewelding conditions,comparedwith thewelding by supplying pure argon, argon + 67% helium mixture by conventional method and thewelding by supplying alternately pure argon and pure helium by alternate method showed the increased welding speed. Also, the alternate method showed the same welding speed with argon + 67% helium mixture without largely deteriorating of weld penetration. The alternate method with argon and helium compared with the conventional methods of pure argon and argon + 67% helium mixture produced the lowest degree of welding distortion.

Characteristics of alternate supply of shielding gases in aluminum GMA welding

Recently, unlike conventional method in supplying shielding gas, a newly method which alternately supplies different kinds of shielding gases in weld zone is developed and partly commercialized. However, literature related to the present status of the technology in the actual weld field is very scant. To give better understand on this technology, this study was performed. Compared with conventional gas supply method, the variations of weld porosity and weld shape in aluminum welding with alternate supply method of pure argon and pure helium were compared with conventional gas supply method with pure argon and argon + 67%helium mixture, respectively. As a result, compared with the welding by supplying pure argon and argon + 67%helium mixture by conventional method, the welding by supplying alternately pure argon and pure helium, produced lower degree of weld porosity and deeper and broader weld penetration profile.