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A Study of Cell Dimensions, Amyloplast Position and Certain Physiological Responses During Gravitropic Bending of Dicot StemsSliwinski, Julianne E. 01 May 1982 (has links)
If a plant is positioned horizontally, the elongating region responds by bending upward within 10 to 12 h until it is vertical, forming a goo bend with the stem below. If a Xan thiv~ strumarium L. (cocklebur) plant is placed horizontally, but restricted to that position for 48 h and then released, the bend to the vertical usually takes place within 10 s, suggesting that bending energy is stored in restricted stems . Some plants that do not bend completely to 90 within 10 s do so within 5 min, and other plants can overshoot the 90 mark by as much as sao. Microscopic measurements show that cells on the bottom of stems that have been restricted and then released are longer and narrower than cells on the bottom of restricted stems; cells on the top of restricted-and-released stems are shorter and thicker than those on the top of restricted stems . Thus, stems bend upward rapidly after release in response to changes in cell dimensions, but apparently with conservation of cell volume (i.e., little or no movement of water in or out of cells during the rapid bending ). The increased diameter of the cells on the bottom of restricted plants indicates that the cells are taking up water before they are released {apparently accompanied by an increase in cell wall area), while they are not allowed to increase much in length. Any increase in length was accompanied by stretching of cells on top. Thus, energy for bending was stored in stretched upper cells and compressed lower cells that have taken up water.
It was al so shown that graviperception takes place in the very tissue that bends, and this perception is not a perception of the tension and compression caused by the weight of a horizontal stem.
Also, amyloplasts were found in a sheath also in the region of bending and were found to settle in the direction of gravity. The location of the sheath between the vascular tissue and the cortex lead to a proposed model of graviperception for green vegetative dicot shoots.
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Akutjournalens övergång till digital plattform : Vad som krävs för att ersätta pappersformatetHallström, Linda January 2015 (has links)
På akutmottagningen vid Universitetssjukhuset i Linköping arbetar personalen idag med en akutjournal i pappersformat. Dokumentationen i akutjournalen påbörjas då en patient anländer till väntrummet och under patientens vistelse fylls den på med information av sjuksköterskor, undersköterskor och läkare. Akutjournalen passerar under sitt flöde både läkarsekreterare, ledningssjuksköterska, sjuksköterska, undersköterska och läkare vilka samtliga bidrar till att informationen i akutjournalen slutligen hamnar i det digitala journalsystemet COSMIC.Syftet med denna studie var att undersöka hur akutjournalen på akutmottagningen vid Universitetssjukhuset i Linköping används för att ta reda på vilka krav som ställs på en digital plattform om akutjournalen ska överföras till en sådan.Observationer och Contextual Inquiry har använts för att samla in data. Data har sedan analyserats med metoden Distributed Cognition for Teamwork.Studien resulterade i beskrivningar av informationsflödet på akutmottagningen, akutmottagningens fysiska layout samt akutjournalens flöde och dess fysiska layout. I beskrivningarna identifierades sedan krav på vad en digital plattform för akutjournalen bör innehålla, vilka sammanfattades i en kravspecifikation.
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AI-systems möjligheter i enavancerad support- och industrikontext / AI-systems possbilities in an advanced support- and industry contextOlsson, Linn January 2019 (has links)
En fallstudie för Siemens i deras supportorganisation där deras arbeteundersöks och dess möjligheter att nyttja ett AI-system för förbättringar.Detta undersöks med hjälp av teorier inom distribuerad kognitionsamt vad som finns tillgängligt inom AI-system likt chatbotar.Genom kontextuella intervjuer inom ramarna för Kontextuell design skapasaffinitetsdiagram och DiCoT analys av datan för att ge en omfattandebild. Detta används för att diskutera de konsekvenser för design av ettAI-system som deras distribuerade kunskapsarbete behöver. Genom resultatetåskådliggörs de många system supportteknikerna använder ochhur de tar hjälp av varandra för att lösa det svårigheter de stöter på. Islutsatsen lyfts det fram förslag på införande av AI-system för supportteknikernamen även en alternativ lösning som är kundorienterad. / A case studie at Siemens supportorganisation is studied and the possibilities to use an AI-system for improvements. This is studied with theories in distributed cognition and what is available in AI-systems such as chatbots. Through contextual inquiry, which is a part of the method Contextual Design, affinity diagrams were made and a analysis through DiCoT to create a relevant image. This is used to discuss consequences for the design of an AI-system that the supporttechnicians need. Through the result the many systems that the supporttechnicians use are illustrated and how they depend on eachother to solve difficulties. In the conclusion different suggestions are made about a AI-system for the support technicians but also an alternative that is customer related.
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Work and Safety in Small to Medium-Sized Air Traffic Control Towers : A Study of Distributed Cognition and ResilienceLinger, Oscar January 2016 (has links)
Air Traffic Control (ATC) is a safety-critical system which places high demands on air traffic controllers’ (ATCO) multitasking abilities. Having the requisite information for well-informed decision making is central, and as new technologies such as remote towers demand an increase in capacity, efficiency, and safety there is a need for research that informs system development. Adopting a systems perspective, Distributed Cognition is an approach for investigating system functioning, and Resilience Engineering is a way of observing safety factors in everyday work. The purpose of this study is to understand how air traffic controllers work from a distributed cognition perspective, and manage safety in everyday tasks from a resilience perspective. Six observations and six interviews were conducted in a Swedish control tower. The data was analyzed using Distributed Cognition for Teamwork (DiCoT) and Resilience markers (REM), which both focus on the transformation and propagation of information. The results of DiCoT show how cognitive processes in ATCO work are supported in models of physical layout, artefacts, information flow, social organization, and evolutionary design. The results of REM show potential for resilience enhancing behavior in several episodes of ATCO work. Moreover, the results suggest that methods such as DiCoT and REM may work well in the ATC domain, as well as complementary to each other. The results may be used for informing system development, and enable a before-and-after study as the control tower of study will be transformed into a remote tower.
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Distribuerad spelledning : Kartläggning, analys och utvecklingsförslag av spelledarens roll i Emergo Train SystemFritz, Emil January 2016 (has links)
Denna uppsats har ämnat kartlägga rollen som spelledare i Katastrofmedicinskt Centrums övningsverktyg Emergo Train System för att sedan göra det möjligt att ta fram ett prototypgränssnitt till det uppkommande DigEmergo. Spelledarens roll har kartlagts med utgångspunkt i distribuerad kognition och utvalda principer ur DiCoT. Vid utformning av gränssnittet har Normans handlingscykel varit underlag och gränssnittet har utvärderats med hjälp av heuristisk utvärdering. Uppsatsens datainsamling har skett genom intervjuer med spelledare och observationer av övningar på Katastrofmedicinskt Centrum. Ur den analyserade datan togs en kravspecifikation fram, denna baserades bland annat på förbättringspotential för användarens situationsmedvetenhet. En prototyp med mål att uppfylla den kravspecifikation samt understödja situationsmedvetenhet och rikta spelledarens uppmärksamhet dit den framgick var ämnad togs fram och utvärderades tillsammans med en spelledare.
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Medierade avbrott inom tillverkningsindustrin / Mediated interruptions in manufacturingGuendert, Jonna January 2015 (has links)
Avbrott inom tillverkningsindustrin är en tids- och kostnadsintensiv händelse som kan leda till allvarliga konsekvenser för produktionen och montörerna. Avbrottsforskning i sig är dock väldigt spretig och det finns knappast några avbrottstudier utförda inom tillverkningsindustrin. Studien som utfördes i det här arbetet var i form av en simulering som efterliknade verkliga förhållanden. Distribuerad kognition användes som teoretiskt ramverk och DiCoT (Distributed Cognition for Teamwork) som metod för att få djupare insikter om hur montörer hanterar avbrott och vad som kan göras för att underlätta återupptagandet av primäruppgiften efter avbrottet. I simuleringen användes den medierade formen av avbrott som skedde via ett notifieringssystem. Resultatet visar att blandningen av olika representationsformer av information i primär – och sekundäruppgiften försvårade återupptagandet av primäruppgiften. Baserat på erhållna resultat formulerades några generella rekommendationer för hur man kan reducera den kognitiva belastningen i avbrotts- och återhämtningsfasen. Studien visar också att det är möjligt att överföra simuleringsresultat till verkliga förhållanden. DiCoT som metod för att applicera distribuerad kognition var svår att använda eftersom metoden inte tar hänsyn till representationsformerna av information vilket är viktigt i det här sammanhanget. Därför skapades ett eget representationsformat (tabell) som synliggjorde hur kognitionen distribuerades över tid och över de olika ingående delarna i simuleringen. Det här arbetet har skett i samverkan med EU-projektet ”Sense & React” som har som syfte att utveckla notifieringssystem som tar hänsyn till montörernas kontext. Nyckelord: medierat avbrott, tillverkningsindustri, notifieringssystem, distribuerad kognition, DiCoT, simulering, representationsformer. / EU- projekt Sense & React
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The Roles of Mechanical Stress and Ethylene in Clinostat-Induced Leaf Epinasty and Gravitropic Response of Dicot ShootsWheeler, Raymond M. 01 May 1981 (has links)
Aminoethoxyvinyl glycine (AVG) and silver thiosulfate, antagonists of ethylene biosynthesis and action in plants, both delayed onset of leaf epinasty in Xanthium strumarium L. (cocklebur) plants rotated on horizontal clinostats. Xanthium plants mechanically stressed by continuous horizontal or vertical shaking, or continuous twisting back and forth, did not develop any significant epinasty, while plants inverted every 20 minutes (upside down half the time) did develop epinasty. From this it appears that clinostat-induced epinasty is a result of gravity compensation rather than mechanical stress.
Treatment of Xanthium, Lycopersicon esculentum Mill. (tomato), and Ricinus communis L. (castor bean) plants with inhibitors of ethylene biosynthesis, AVG and cobaltous ion, and inhibitors of ethylene action, silver ion and carbon dioxide, significantly delayed stem gravitropic response times. AVG and silver were dependably effective in delaying gravitropism, while carbon dioxide and cobalt were less effective.
Unilateral application of ethephon solution (1%) to the upper 10 centimeters of tomato stems, caused stems to deflect up to 80° toward the side of application after 24 hours on a clinostat, while unilateral application of indole-3-acetic acid in lanolin paste (1%) to tomato and cocklebur stems caused up to 250° and 200° bending respectively, away from the side of application after 24 hours on a clinostat.
Cocklebur stems that are restricted from bending after placing them horizontally store bending energy as seen from the springing upward that occurs when the stems are released (up to an average of 150° after 40 hours of restriction). Most of these stems also showed a stored stimulus of gravitropic bending, continuing to bend for several hours after release and being placed upright, before straightening.
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Algumas respostas de mono- e dicotiledôneas a auxinas associadas à ação do etileno / Responses of mono- and dicots to auxins associated with the ethylene actionMedina, Eduardo Ferreira 27 February 2013 (has links)
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Previous issue date: 2013-02-27 / The auxins IAA (indole-3-acetic, natural), 2,4-D (2,4-dichlorophenoxyacetic acid) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid, the latter two synthetic) were sprayed on corn (Zea mays, monocot) and beans (Phaseolus vulgaris, dicot), in order to investigate some differential responses of the two plant groups as associated to ethylene metabolism. Corn plants treated with the auxins did not produce ethylene, not exhibiting also any senescence symptom. Beans plants, on the other hand, produced large amounts of ethylene following treatment with auxins. Aminoethoxyvinylglycine (AVG) plus Co2+ (ethylene biosynthesis inhibitors) were not able to relieve the epinasty, drying and leaf wrinkling effects in bean plants, but leaf yellowing was considerebly reduced, suggesting this was an ethylene effect. Following spraying with auxins, corn plants showed no production of 1-aminocyclopropane-1-carboxylic acid (ACC), a response shown by beans plants. Therefore in the monocot, auxins seemed not to induce the expression of ACC synthase (ACS) or its activity. When treated with ACC, corn plants failed to produce any trace of ethylene, unlikely bean plants. This suggested that in monocot, auxins seemed also not to induce the expression or activity of ACC oxidase (ACO) or the enzyme is not activated. Potassium ferrocyanide, employed as a source of cyanide ions, was much more toxic to bean plants than to corn and so the monocot seemed to be more resistant than bean plants. Maximum quantum yield of photosystem II (Fv/Fm) and photosynthetic pigments contents kept unchanged in corn plants treated with the auxins. Bean plants showed significant decreases in both variables following spraying with 2,4-D and 2,4,5-T. Decreases in chlorophyll contents in bean plants treated with 2,4-D and 2,4,5-T correlated well with leaf chlorosis what was shown to be due to a more pronounced fall of chlorophyll contents rather than to an increase in carotenoid contents. The xanthophylls (neoxanthin, violaxanthin and anteraxantina) also showed a higher degradation than the alpha and beta carotenes in bean plants treated with 2,4-D and 2,4,5-T. When AVG and Co2+ were supplied together with auxin, no appreciable decrease in either the Fv/Fm ratio or pigment contents was observed, with the exception of alpha carotene. Also the ratio of chlorophyll a to chlorophyll b was also larger in bean plants treated with 2,4-D and 2,4,5-T than in the plants treated with 2,4-D and 2,4,5-T plus AVG and Co2+. The ratio of chlorophyll a to chlorophyll b did not show any significance in bean plants upon treatment with IAA. / As auxinas AIA (ácido indol-3-acético, natural), 2,4-D (ácido 2,4-diclorofenoxiacético) e 2,4,5-T (ácido 2,4,5-triclorofenoxiacético, as duas últimas sintéticas) foram aplicadas em plantas de milho (Zea mays, monocotiledônea) e feijão (Phaseolus vulgaris, dicotiledônea), visando investigarem-se algumas respostas diferenciais dos dois grupos em relação ao metabolismo do etileno. Plantas de milho tratadas com as auxinas não produziram etileno e não exibiram quaisquer sintomas de senescência e epinastia. O feijão produziu bastante etileno após tratamento. Quando se utilizou aminoetoxivinilglicina (AVG) mais Co2+ (inibidores da biossíntese de etileno), a epinastia das plantas de feijão foi mantida mas o amarelecimento das plantas mostrou-se reduzido, deduzindo-se ser o amarelecimento um sintoma da ação do etileno. Após pulverização com as auxinas, o milho não exibiu produção do ácido 1-carboxílico-1- amino-ciclopropano (ACC), fato observado no feijão. Assim, na monocotiledônea, as auxinas parecem não induzir a expressão da sintase do ACC (ACS) ou, pelo menos, sua atividade. Quando tratadas com o ACC, as plantas de milho não produziram qualquer traço de etileno, ao contrário as plantas de feijão. Daí deduzir-se que na monocotiledônea, as auxinas parecem também não induzir a expressão ou atividade da oxidase do ACC (ACO) ou a enzima não é ativada. Empregando-se K4Fe(CN)6 como fonte de íons cianeto, as plantas de milho pareceram se mostrar mais resistentes à intoxicação do que as plantas de feijão. O rendimento quântico máximo de fotossistema II (razão Fv/Fm) e os níveis dos pigmentos fotossintéticos não sofreram alterações em plantas de milho tratadas com as auxinas. As plantas de feijão mostraram quedas significativas em ambas variáveis após pulverização com 2,4-D e 2,4,5-T, mas não com o AIA. A redução nos níveis das clorofilas em plantas de feijão tratadas com 2,4-D e 2,4,5-T relacionou-se com a clorose observada, desde que ocorreu uma degradação mais acentuada das clorofilas do que dos carotenoides. As xantofilas (neoxantina, anteraxantina e violaxantina) também sofreram uma degradação mais acentuada do que o alfa e beta caroteno em plantas de feijão tratadas com 2,4-D e 2,4,5-T. Quando AVG e Co2+ foram fornecidos conjuntamente com as auxinas, não ocorreu queda na razão Fv/Fm e nem no nível dos pigmentos, com exceção do alfa caroteno. A razão entre clorofila a e clorofila b também mostrou-se maior nas plantas de feijão tratadas com 2,4-D e 2,4,5-T do que nas plantas tratadas com 2,4-D e 2,4,5-T mais AVG e Co2+. Nas plantas tratadas com AIA o aumento na razão entre clorofila a e clorofila b não foi significativo.
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Distribuerade kognitiva system i hälso- och sjukvård : En fallstudie utifrån "DiCoT" (Distributed Cognition for Teamwork)Palmér, Annelie January 2014 (has links)
Svensk hälso- och sjukvård är en informationsintensiv bransch som står inför en stor utmaning avseende de informationsteknologiska lösningar som används idag och hur dessa lösningar bör utvecklas framöver. Vårdpersonalen efterfrågar att den teknologi som används ska vara flexibel och anpassad till arbetssituationen samt följa flödet i patientprocessen. För att utveckla lösningar anpassade till vård och omsorg som kan stödja användarna i deras arbetssituation krävs att metoder utvecklas utifrån användarna och deras arbetskontext i en distribuerad arbetsmiljö. Genom att ta fram sådana metoder utifrån ansatsen distribuerad kognition blir det möjligt att identifiera informationsflöden och de verktyg som används utifrån de fysiska förutsättningarna i arbetskontexten. Distribuerad kognition utgår från att människans tänkande ses som ett fenomen som utgår från social, kulturell och kontextuell interaktion samt interaktion med artefakter, Kognition anses på så sätt vara distribuerad. Denna rapport avser analysera DiCoT som utvecklats utifrån den distribuerade ansatsen och som är avsedd att användas som analysverktyg vid utveckling av nya informationsteknologiska lösningar och lämpar sig väl för arbetskontexter inom hälso- och sjukvård. För att analysera DiCoT har en etnografisk kvalitativ studie utförts och resultatet har visat att DiCoT fungerar väl som analysverktyg inom sjukvårdsmiljöer men att det finns områden så som sociala strukturer, avbrott i arbetsprocesser och indirekta interaktionsmönster som behöver beaktas och som kan komma att påverkas när dessa typer av sjukvårdsmiljöer digitaliseras.
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