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Palacios Chavez, Johanna Lisset - One of the best experts on this subject based on the ideXlab platform.
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Propuesta de mejora para optimizar el proceso de carga de combustibles líquidos en camiones Cisterna, en una empresa de refino de hidrocarburos, Lima 2017 (Tesis parcial)
'Dipartimento di Economia Universita di Perugia (IT)', 2018Co-Authors: Palacios Chavez, Johanna LissetAbstract:ABSTRACT The objective of this work is to improve the process of loading liquid fuels in tanker trucks at a hydrocarbon refining company, Lima 2017; this process takes place in the supplies - dispatches area, which has approximately 28 people among operators. plant, dispatch operators, island operators and control room operators, due to the increase in the oil and gas industry, the hydrocarbon refining company seeks to improve its loading process, optimizing the start and end times of the dispatch. For this purpose, the use of analysis tools such as Ishikawa, flow grams, Monte Carlo method and the survey of information in the field in order to take knowledge of the service times in the dispatch flow, later a model is developed of waiting line for two cases. 1) Current situation model, in which its population is 277 cistern / day and 2) A waiting line model considering an existing service peak of 386 cistern / day. Key words: loading process, process optimization, down time, continuous improvement, liquid fuels, lead time, tanker truck service, process management, among others.TesisRESUMEN El presente trabajo tiene como objetivo mejorar el proceso de carga de combustibles líquidos en camiones Cisternas en una empresa de refino de hidrocarburos, Lima 2017, dicho proceso se desarrolla en el área de suministros – despachos, la cual cuenta con aproximadamente 28 personas entre operadores de planta, operadores de despachos, operadores de isla y operadores de sala de control, debido al incremento del rubro de gas y petróleo, la empresa de refino de hidrocarburos busca mejorar su proceso de carga, optimizando los tiempos de inicio y fin del despacho. Para ello se realizó, el uso de herramientas de análisis como Ishikawa, flujo gramas, método de Monte Carlo y el relevamiento de información en el campo a fin de tomar conocimiento de los tiempos de servicio en el flujo de despacho, posteriormente se desarrolla un modelo de línea de espera para dos casos. 1) Modelo de situación actual, en la cual su población es de 277 Cisterna/día y 2) Un modelo de línea de espera considerando un pico de atención existente de 386 Cisterna/día. Palabras Claves: proceso de carga, optimización de procesos, down time, mejora continua, combustibles líquidos, lead time, atención de camiones Cisternas, gestión de procesos, entre otros
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Propuesta de mejora para optimizar el proceso de carga de combustibles líquidos en camiones Cisterna, en una empresa de refino de hidrocarburos, Lima 2017.
Universidad Privada del Norte, 2017Co-Authors: Palacios Chavez, Johanna LissetAbstract:RESUMEN El presente trabajo tiene como objetivo mejorar el proceso de carga de combustibles líquidos en camiones Cisternas en una empresa de refino de hidrocarburos, Lima 2017, dicho proceso se desarrolla en el área de suministros – despachos, la cual cuenta con aproximadamente 28 personas entre operadores de planta, operadores de despachos, operadores de isla y operadores de sala de control, debido al incremento del rubro de gas y petróleo, la empresa de refino de hidrocarburos busca mejorar su proceso de carga, optimizando los tiempos de inicio y fin del despacho. Para ello se realizó, el uso de herramientas de análisis como Ishikawa, flujo gramas, método de Monte Carlo y el relevamiento de información en el campo a fin de tomar conocimiento de los tiempos de servicio en el flujo de despacho, posteriormente se desarrolla un modelo de línea de espera para dos casos. 1) Modelo de situación actual, en la cual su población es de 277 Cisterna/día y 2) Un modelo de línea de espera considerando un pico de atención existente de 386 Cisterna/día. Palabras Claves: proceso de carga, optimización de procesos, down time, mejora continua, combustibles líquidos, lead time, atención de camiones Cisternas, gestión de procesos, entre otros.ABSTRACT The objective of this work is to improve the process of loading liquid fuels in tanker trucks at a hydrocarbon refining company, Lima 2017; this process takes place in the supplies - dispatches area, which has approximately 28 people among operators. plant, dispatch operators, island operators and control room operators, due to the increase in the oil and gas industry, the hydrocarbon refining company seeks to improve its loading process, optimizing the start and end times of the dispatch. For this purpose, the use of analysis tools such as Ishikawa, flow grams, Monte Carlo method and the survey of information in the field in order to take knowledge of the service times in the dispatch flow, later a model is developed of waiting line for two cases. 1) Current situation model, in which its population is 277 cistern / day and 2) A waiting line model considering an existing service peak of 386 cistern / day. Key words: loading process, process optimization, down time, continuous improvement, liquid fuels, lead time, tanker truck service, process management, among others
Andrew L Staehelin - One of the best experts on this subject based on the ideXlab platform.
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3d electron tomographic and biochemical analysis of er golgi and trans golgi network membrane systems in stimulated venus flytrap dionaea muscipula glandular cells
Journal of Biological Research-thessaloniki, 2018Co-Authors: Zachary R Gergely, Dana Ethel Martinez, Bryon S Donohoe, Soren Mogelsvang, Rachel Herder, Andrew L StaehelinAbstract:The insect-trapping leaves of Dionaea muscipula provide a model for studying the secretory pathway of an inducible plant secretory system. The leaf glands were induced with bovine serum albumin to secrete proteases that were characterized via zymogram activity gels over a 6-day period. The accompanying morphological changes of the endoplasmic reticulum (ER) and Golgi were analyzed using 3D electron tomography of glands preserved by high-pressure freezing/freeze substitution methods. Secretion of multiple cysteine and aspartic proteases occurred biphasically. The majority of the Golgi was organized in clusters consisting of 3–6 stacks surrounded by a cage-like system of ER Cisternae. In these clusters, all Golgi stacks were oriented with their cis-most C1 Cisterna facing an ER export site. The C1 Golgi Cisternae varied in size and shape consistent with the hypothesis that they form de novo. Following induction, the number of ER-bound polysomes doubled, but no increase in COPII vesicles was observed. Golgi changes included a reduction in the number of Cisternae per stack and a doubling of Cisternal volume without increased surface area. Polysaccharide molecules that form the sticky slime cause swelling of the trans and trans Golgi network (TGN) Cisternae. Peeling of the trans-most Cisternae gives rise to free TGN Cisternae. One day after gland stimulation, the free TGNs were frequently associated with loose groups of oriented actin-like filaments which were not seen in any other samples. These findings suggest that the secretory apparatus of resting gland cells is “overbuilt” to enable the cells to rapidly up-regulate lytic enzyme production and secretion in response to prey trapping.
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3D electron tomographic and biochemical analysis of ER, Golgi and trans Golgi network membrane systems in stimulated Venus flytrap (Dionaea muscipula) glandular cells
BMC, 2018Co-Authors: Zachary R Gergely, Dana Ethel Martinez, Bryon S Donohoe, Soren Mogelsvang, Rachel Herder, Andrew L StaehelinAbstract:Abstract Background The insect-trapping leaves of Dionaea muscipula provide a model for studying the secretory pathway of an inducible plant secretory system. The leaf glands were induced with bovine serum albumin to secrete proteases that were characterized via zymogram activity gels over a 6-day period. The accompanying morphological changes of the endoplasmic reticulum (ER) and Golgi were analyzed using 3D electron tomography of glands preserved by high-pressure freezing/freeze substitution methods. Results Secretion of multiple cysteine and aspartic proteases occurred biphasically. The majority of the Golgi was organized in clusters consisting of 3–6 stacks surrounded by a cage-like system of ER Cisternae. In these clusters, all Golgi stacks were oriented with their cis-most C1 Cisterna facing an ER export site. The C1 Golgi Cisternae varied in size and shape consistent with the hypothesis that they form de novo. Following induction, the number of ER-bound polysomes doubled, but no increase in COPII vesicles was observed. Golgi changes included a reduction in the number of Cisternae per stack and a doubling of Cisternal volume without increased surface area. Polysaccharide molecules that form the sticky slime cause swelling of the trans and trans Golgi network (TGN) Cisternae. Peeling of the trans-most Cisternae gives rise to free TGN Cisternae. One day after gland stimulation, the free TGNs were frequently associated with loose groups of oriented actin-like filaments which were not seen in any other samples. Conclusions These findings suggest that the secretory apparatus of resting gland cells is “overbuilt” to enable the cells to rapidly up-regulate lytic enzyme production and secretion in response to prey trapping
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electron tomography of raba4b and pi 4kβ1 labeled trans golgi network compartments in arabidopsis
Traffic, 2011Co-Authors: Byungho Kang, Erik Nielsen, Mary L Preuss, David N Mastronarde, Andrew L StaehelinAbstract:The trans Golgi network (TGN) of plant cells sorts and packages Golgi products into secretory (SV) and clathrin-coated (CCV) vesicles. We have analyzed of TGN Cisternae in Arabidopsis root meristem cells by cell fractionation and electron microscopy/tomography to establish reliable criteria for identifying TGN Cisternae in plant cells, and to define their functional attributes. Transformation of a trans Golgi Cisterna into a Golgi-associated TGN Cisterna begins with Cisternal peeling, the formation of SV buds outside the plane of the Cisterna and a 30–35% reduction in Cisternal membrane area. Free TGN compartments are defined as Cisternae that have detached from the Golgi to become independent organelles. Golgi-associated and free TGN compartments, but not trans Golgi Cisternae, bind anti-RabA4b and anti-phosphatidylinositol-4 kinase (PI-4K) antibodies. RabA4b and PI-4Kβ1 localize to budding SVs in the TGN and to SVs en route to the cell surface. SV and CCV release occurs simultaneously via Cisternal fragmentation, which typically yields ∼30 vesicles and one to four residual Cisternal fragments. Early endosomal markers, VHA-a1-green fluorescent protein (GFP) and SYP61-cyan fluorescent protein (CFP), colocalized with RabA4b in TGN Cisternae, suggesting that the secretory and endocytic pathways converge at the TGN. pi4k1/pi4k2 knockout mutant plants produce SVs with highly variable sizes indicating that PI-4Kβ1/2 regulates SV size.
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golgi structure in three dimensions functional insights from the normal rat kidney cell
Journal of Cell Biology, 1999Co-Authors: Mark S Ladinsky, David N Mastronarde, Richard J Mcintosh, Kathryn E Howell, Andrew L StaehelinAbstract:Three-dimensional reconstructions of portions of the Golgi complex from cryofixed, freeze-substituted normal rat kidney cells have been made by dual-axis, high-voltage EM tomography at ∼7-nm resolution. The reconstruction shown here (∼1 × 1 × 4 μm3) contains two stacks of seven Cisternae separated by a noncompact region across which bridges connect some Cisternae at equivalent levels, but none at nonequivalent levels. The rest of the noncompact region is filled with both vesicles and polymorphic membranous elements. All Cisternae are fenestrated and display coated buds. They all have about the same surface area, but they differ in volume by as much as 50%. The trans-most Cisterna produces exclusively clathrin-coated buds, whereas the others display only nonclathrin coated buds. This finding challenges traditional views of where sorting occurs within the Golgi complex. Tubules with budding profiles extend from the margins of both cis and trans Cisternae. They pass beyond neighboring Cisternae, suggesting that these tubules contribute to traffic to and/or from the Golgi. Vesicle-filled “wells” open to both the cis and lateral sides of the stacks. The stacks of Cisternae are positioned between two types of ER, cis and trans. The cis ER lies adjacent to the ER-Golgi intermediate compartment, which consists of discrete polymorphic membranous elements layered in front of the cis-most Golgi Cisterna. The extensive trans ER forms close contacts with the two trans-most Cisternae; this apposition may permit direct transfer of lipids between ER and Golgi membranes. Within 0.2 μm of the Cisternae studied, there are 394 vesicles (8 clathrin coated, 190 nonclathrin coated, and 196 noncoated), indicating considerable vesicular traffic in this Golgi region. Our data place structural constraints on models of trafficking to, through, and from the Golgi complex.
Yukitaka Ushio - One of the best experts on this subject based on the ideXlab platform.
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microcatheter intrathecal urokinase infusion into Cisterna magna for prevention of cerebral vasospasm preliminary report
Stroke, 2000Co-Authors: Junichiro Hamada, Takamasa Mizuno, Yutaka Kai, Motohiro Morioka, Yukitaka UshioAbstract:Background and Purpose —The feasibility of preventing vasospasm by intrathecal anterograde infusion of urokinase (UK) into the Cisterna magna was studied in patients with recently ruptured aneurysms who had just undergone the placement of a Guglielmi detachable coil (GDC). Methods —Immediately after complete embolization with the use of GDC-10 coils, 15 patients with Hunt and Hess neurological grades III and IV received 60 000 IU of UK in normal saline through a microcatheter advanced into the Cisterna magna. UK infusion was repeated once or twice over a period of 2 to 3 days according to a decision based on CT evidence of a subarachnoid clot remaining in the cisterns. Before administering the last UK infusion, we obtained CT confirmation of almost complete clearance of clots in the basal cisterns. Results —In all 15 patients, the microcatheter was advanced easily into the Cisterna magna by use of the over-the-wire microcatheter technique. In 8 patients who received thrombolytic therapy within 24 hours of the ictus, there was almost complete clearance of the clot in the basal cisterns within 2 days of suffering the insult. When UK was injected at 24 to 48 hours after the insult, 7 patients manifested CT evidence of clearance at the latest 4 days after suffering the insult. In all 15 patients, CT scans obtained within 24 hours of the final UK administration showed complete resolution of clots in the basal cistern and almost complete resolution of clots in the basal interhemispheric fissure and bilateral proximal sylvian fissures. Although one patient developed a transient neurological deficit, no patients manifested permanent delayed neurological deficits as a result of vasospasm. Outcome assessment according to the Glasgow Outcome Scale, no less than 3 months after GDC placement, revealed good recovery in all patients, and none developed hydrocephalus requiring a shunt procedure. Conclusions —In patients with recently ruptured aneurysms, GDC placement followed by immediate intrathecal administration of UK from the Cisterna magna may be a safe and reasonable means of preventing vasospasms and may result in improved treatment outcomes.
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microcatheter intrathecal urokinase infusion into Cisterna magna for prevention of cerebral vasospasm
Stroke, 2000Co-Authors: Junichiro Hamada, Takamasa Mizuno, Yutaka Kai, Motohiro Morioka, Yukitaka UshioAbstract:The feasibility of preventing vasospasm by intrathecal anterograde infusion of urokinase (UK) into the Cisterna magna was studied in patients with recently ruptured aneurysms who had just undergone the placement of a Guglielmi detachable coil (GDC). Immediately after complete embolization with the use of GDC coils, 20 patients with Hunt and Hess neurological grades 3 and 4 received 60000 IU of UK in normal saline through a microcatheter advanced into the Cisterna magna. UK infusion was repeated once or twice over a period of 2–3 days according to a decision based on CT evidence of a subarachnoid clot remaining in the cisterns. In all 20 patients, the microcatheter was advanced easily into the Cisterna magna by use of the over-the-wire microcatheter technique. In 12 patients who received thrombolytic therapy within 24 h of the ictus, there was almost complete clearance of the clot in the basal cistern within 2 days of the suffering the insult. When UK was injected at 24–48 h after the insult, 8 patients manifested CT evidence of clearance at the latest 4 days after suffering the insult. In patients with recently ruptured aneurysms, GDC placement followed by immediate intrathecal administration of UK from the Cisterna magna may be a safe and reasonable means of preventing vasospasms.
Junichiro Hamada - One of the best experts on this subject based on the ideXlab platform.
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microcatheter intrathecal urokinase infusion into Cisterna magna for prevention of cerebral vasospasm preliminary report
Stroke, 2000Co-Authors: Junichiro Hamada, Takamasa Mizuno, Yutaka Kai, Motohiro Morioka, Yukitaka UshioAbstract:Background and Purpose —The feasibility of preventing vasospasm by intrathecal anterograde infusion of urokinase (UK) into the Cisterna magna was studied in patients with recently ruptured aneurysms who had just undergone the placement of a Guglielmi detachable coil (GDC). Methods —Immediately after complete embolization with the use of GDC-10 coils, 15 patients with Hunt and Hess neurological grades III and IV received 60 000 IU of UK in normal saline through a microcatheter advanced into the Cisterna magna. UK infusion was repeated once or twice over a period of 2 to 3 days according to a decision based on CT evidence of a subarachnoid clot remaining in the cisterns. Before administering the last UK infusion, we obtained CT confirmation of almost complete clearance of clots in the basal cisterns. Results —In all 15 patients, the microcatheter was advanced easily into the Cisterna magna by use of the over-the-wire microcatheter technique. In 8 patients who received thrombolytic therapy within 24 hours of the ictus, there was almost complete clearance of the clot in the basal cisterns within 2 days of suffering the insult. When UK was injected at 24 to 48 hours after the insult, 7 patients manifested CT evidence of clearance at the latest 4 days after suffering the insult. In all 15 patients, CT scans obtained within 24 hours of the final UK administration showed complete resolution of clots in the basal cistern and almost complete resolution of clots in the basal interhemispheric fissure and bilateral proximal sylvian fissures. Although one patient developed a transient neurological deficit, no patients manifested permanent delayed neurological deficits as a result of vasospasm. Outcome assessment according to the Glasgow Outcome Scale, no less than 3 months after GDC placement, revealed good recovery in all patients, and none developed hydrocephalus requiring a shunt procedure. Conclusions —In patients with recently ruptured aneurysms, GDC placement followed by immediate intrathecal administration of UK from the Cisterna magna may be a safe and reasonable means of preventing vasospasms and may result in improved treatment outcomes.
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microcatheter intrathecal urokinase infusion into Cisterna magna for prevention of cerebral vasospasm
Stroke, 2000Co-Authors: Junichiro Hamada, Takamasa Mizuno, Yutaka Kai, Motohiro Morioka, Yukitaka UshioAbstract:The feasibility of preventing vasospasm by intrathecal anterograde infusion of urokinase (UK) into the Cisterna magna was studied in patients with recently ruptured aneurysms who had just undergone the placement of a Guglielmi detachable coil (GDC). Immediately after complete embolization with the use of GDC coils, 20 patients with Hunt and Hess neurological grades 3 and 4 received 60000 IU of UK in normal saline through a microcatheter advanced into the Cisterna magna. UK infusion was repeated once or twice over a period of 2–3 days according to a decision based on CT evidence of a subarachnoid clot remaining in the cisterns. In all 20 patients, the microcatheter was advanced easily into the Cisterna magna by use of the over-the-wire microcatheter technique. In 12 patients who received thrombolytic therapy within 24 h of the ictus, there was almost complete clearance of the clot in the basal cistern within 2 days of the suffering the insult. When UK was injected at 24–48 h after the insult, 8 patients manifested CT evidence of clearance at the latest 4 days after suffering the insult. In patients with recently ruptured aneurysms, GDC placement followed by immediate intrathecal administration of UK from the Cisterna magna may be a safe and reasonable means of preventing vasospasms.
Graham Warren - One of the best experts on this subject based on the ideXlab platform.
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a role for the vesicle tethering protein p115 in the post mitotic stacking of reassembling golgi Cisternae in a cell free system
Journal of Cell Biology, 1999Co-Authors: James Shorter, Graham WarrenAbstract:During telophase, Golgi Cisternae are regenerated and stacked from a heterogeneous population of tubulovesicular clusters. A cell-free system that reconstructs these events has revealed that Cisternal regrowth requires interplay between soluble factors and soluble N-ethylmaleimide (NEM)–sensitive fusion protein (NSF) attachment protein receptors (SNAREs) via two intersecting pathways controlled by the ATPases, p97 and NSF. Golgi reassembly stacking protein 65 (GRASP65), an NEM-sensitive membrane-bound component, is required for the stacking process. NSF-mediated Cisternal regrowth requires a vesicle tethering protein, p115, which we now show operates through its two Golgi receptors, GM130 and giantin. p97-mediated Cisternal regrowth is p115-independent, but we now demonstrate a role for p115, in conjunction with its receptors, in stacking p97 generated Cisternae. Temporal analysis suggests that p115 plays a transient role in stacking that may be upstream of GRASP65-mediated stacking. These results implicate p115 and its receptors in the initial alignment and docking of single Cisternae that may be an important prerequisite for stack formation.
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reassembly of golgi stacks from mitotic golgi fragments in a cell free system
Journal of Cell Biology, 1995Co-Authors: Catherine Rabouille, T Misteli, Rose Watson, Graham WarrenAbstract:Rat liver Golgi stacks were incubated with mitotic cytosol for 30 min at 37 degrees C to generate mitotic Golgi fragments comprising vesicles, tubules, and Cisternal remnants. These were isolated and further incubated with rat liver cytosol for 60 min. The earliest intermediate observed by electron microscopy was a single, curved Cisterna with tubular networks fused to the Cisternal rims. Elongation of this Cisterna was accompanied by stacking and further growth at the Cisternal rims. Stacks also fused laterally so that the typical end product was a highly curved stack of 2-3 Cisternae mostly enclosing an electron-lucent space. Reassembly occurred in the presence of nocodazole or cytochalasin B but not at 4 degrees C or in the absence of energy supplied in the form of ATP and GTP. Pretreatment of the mitotic fragments and cytosol with N-ethylmaleimide (NEM) also prevented reassembly. GTP gamma S and A1F prevented reassembly when added during fragmentation but not when added to the reassembly mixture. In fact, GTP gamma S stimulated reassembly such that all Cisternae were stacked at the end of the incubation and comprised 40% of the total membrane. In contrast, microcystin inhibited stacking so that only single Cisternae accumulated. Together these results provide a detailed picture of the reassembly process and open up the study of the architecture of the Golgi apparatus to a combined morphological and biochemical analysis.
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overlapping distribution of two glycosyltransferases in the golgi apparatus of hela cells
Journal of Cell Biology, 1993Co-Authors: Tommy Nilsson, Marc Pypaert, P Slusarewicz, Eric G Berger, Graham WarrenAbstract:Thin, frozen sections of a HeLa cell line were double labeled with specific antibodies to localize the trans-Golgi enzyme, beta 1,4 galactosyltransferase (GalT) and the medial enzyme, N-acetylglucosaminyltransferase I (NAGT I). The latter was detected by generating a HeLa cell line stably expressing a myc-tagged version of the endogenous protein. GalT was found in the trans-Cisterna and trans-Golgi network but, contrary to expectation, NAGT I was found both in the medial- and trans-Cisternae, overlapping the distribution of GalT. About one third of the NAGT I and half of the GalT were found in the shared, trans-Cisterna. These data show that the differences between Cisternae are determined not by different sets of enzymes but by different mixtures.