945 resultados para Integrated operation and maintenance
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There is growing evidence that astrocytes are involved in the neuropathology of major depression. In particular, decreases in glial cell density observed in the cerebral cortex of individuals with major depressive disorder are accompanied by a reduction of several astrocytic markers suggesting that astrocyte dysfunction may contribute to the pathophysiology of major depression. In rodents, glial loss in the prefrontal cortex is sufficient to induce depressive-like behaviors and antidepressant treatment prevents the stress-induced reduction of astrocyte number in the hippocampus. Collectively, these data support the existence of a link between astrocyte loss or dysfunction, depressive-like behavior and antidepressant treatment. Astrocytes are increasingly recognized to play important roles in neuronal development, neurotransmission, synaptic plasticity and maintenance of brain homeostasis. It is also well established that astrocytes provide trophic, structural, and metabolic support to neurons. In this article, we review evidence that antidepressants regulate energy metabolism and neurotrophic factor expression with particular emphasis on studies in astrocytes. These observations support a role for astrocytes as new targets for antidepressants. The contribution of changes in astrocyte glucose metabolism and neurotrophic factor expression to the therapeutic effects of antidepressants remains to be established.
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As streets age, officials must deal with rehabilitating and reconstructing these pavements to maintain a safe and comfortable ride. In light of nationwide budget shortfalls, cost-effective methods of extending pavement service life must be developed or the overall condition of street systems will continue to fall. Thin maintenance surfaces (TMSs) are a set of cost-effective preventive maintenance surfacing techniques that can be used to extend the life of bituminous pavement—pavement built with hot mix asphalt, hot mix asphalt overlays of portland cement concrete pavements, built-up seal coat (chip seal), stabilized materials, or a combination of these. While previous phases of TMS research have provided information about the uses of thin maintenance surfaces in rural settings, urban areas have different road maintenance challenges that should be considered separately. This research provides city street officials with suggestions for TMS techniques that street departments can easily test and include into their current programs. This research project facilitated the construction of TMS test sections in Cedar Rapids, Council Bluffs, and West Des Moines (all urban settings in Iowa). Test section sites and surfaces were selected to suit the needs of municipalities and were applied to roads with an array of various distresses and maintenance needs. Condition surveys of each test section were performed before construction, after construction, and after the first winter to record the amount and severity of existing distress and calculate the pavement condition index. Because conditions of the test sections varied greatly, determining which surface was most successful by comparing case studies was not feasible. However, some general conclusions can be made from this research. TMSs are suitable preventive maintenance techniques for a municipal street department’s program for preserving existing pavements. Careful attention should be paid to proper planning, quality control during construction, aggregate and binder selection, and aggregate embedment in order to support successful TMS application.
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Road dust is caused by wind entraining fine material from the roadway surface and the main source of Iowa road dust is attrition of carbonate rock used as aggregate. The mechanisms of dust suppression can be considered as two processes: increasing particle size of the surface fines by agglomeration and inhibiting degradation of the coarse material. Agglomeration may occur by capillary tension in the pore water, surfactants that increase bonding between clay particles, and cements that bind the mineral matter together. Hygroscopic dust suppressants such as calcium chloride have short durations of effectiveness because capillary tension is the primary agglomeration mechanism. Somewhat more permanent methods of agglomeration result from chemicals that cement smaller particles into a mat or larger particles. The cements include lignosulfonates, resins, and asphalt products. The duration of the cements depend on their solubility and the climate. The only dust palliative that decreases aggregate degradation is shredded shingles that act as cushions between aggregate particles. It is likely that synthetic polymers also provide some protection against coarse aggregate attrition. Calcium chloride and lignosulfonates are widely used in Iowa. Both palliatives have a useful duration of about 6 months. Calcium chloride is effective with surface soils of moderate fine content and plasticity whereas lignin works best with materials that have high fine content and high plasticity indices. Bentonite appears to be effective for up to two years and works well with surface materials having low fines and plasticity and works well with limestone aggregate. Selection of appropriate dust suppressants should be based on characterization of the road surface material. Estimation of dosage rates for potential palliatives can be based on data from this report, from technical reports, information from reliable vendors, or laboratory screening tests. The selection should include economic analysis of construction and maintenance costs. The effectiveness of the treatment should be evaluated by any of the field performance measuring techniques discussed in this report. Novel dust control agents that need research for potential application in Iowa include; acidulated soybean oil (soapstock), soybean oil, ground up asphalt shingles, and foamed asphalt. New laboratory evaluation protocols to screen additives for potential effectiveness and determine dosage are needed. A modification of ASTM D 560 to estimate the freeze-thaw and wet-dry durability of Portland cement stabilized soils would be a starting point for improved laboratory testing of dust palliatives.
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Bridge rail and approach guardrails provide safety to drivers by shielding more hazardous objects and redirecting vehicles to the roadway. However, guardrail can increase both the initial cost and maintenance cost of a bridge, while adding another object that may be struck by vehicles. Most existing low volume road (LVR) bridges in the state of Iowa are currently indicated to not possess bridge rail meeting “current acceptable standards”. The primary objective of the research summarized in this report was to provide the nations bridge and approach rail state of practice and perform a state wide crash analysis on bridge rails and approach guardrails on LVR bridges in Iowa. In support of this objective, the criteria and guidelines used by other bridge owners were investigated, non-standard and innovative bridge and approach guardrails for LVR’s were investigated, and descriptive, statistical and economical analyses were performed on a state wide crash analysis. The state wide crash analysis found the overall number of crashes at/on the more than 17,000+ inventoried and non-inventoried LVR bridges in Iowa was fewer than 350 crashes over an eight year period, representing less than 0.1% of the statewide reportable crashes. In other words, LVR bridge crashes are fairly rare events. The majority of these crashes occurred on bridges with a traffic volume less than 100 vpd and width less than 24 ft. Similarly, the majority of the LVR bridges possess similar characteristics. Crash rates were highest for bridges with lower traffic volumes, narrower widths, and negative relative bridge widths (relative bridge width is defined as: bridge width minus roadway width). Crash rate did not appear to be effected by bridge length. Statistical analysis confirmed that the frequency of vehicle crashes was higher on bridges with a lower width compared to the roadway width. The frequency of crashes appeared to not be impacted by weather conditions, but crashes may be over represented at night or in dark conditions. Statistical analysis revealed that crashes that occurred on dark roadways were more likely to result in major injury or fatality. These findings potentially highlight the importance of appropriate delineation and signing. System wide, benefit-cost (B/C) analyses yielded very low B/C ratios for statewide bridge rail improvements. This finding is consistent with the aforementioned recommendation to address specific sites where safety concerns exist.
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Background/Purpose: Physical exercise is safe and effective as an adjunctive nonpharmacological treatment modality in the management of rheumatoid arthritis (RA). It is well established that patients with RA are less active compared to healthy controls. The transtheoretical model of health promotion, based on five stages of change, provides a useful framework to better understand patients' motivation towards regular exercise. The purpose of this study was to determine the distribution of exercise stages of change in a RA cohort, and to examine barriers, benefits and preferences for exercise. Methods: One hundred and twenty consecutive patients with RA followed at a hospital-based rheumatology practice were invited to participate in the study. Those who accepted to participate filled in a questionnaire to determine their exercise stage of change, their perceived benefits and barriers to exercise, and their preferences for various features of exercise. Disease activity was measured using the disease activity score (DAS28). Other variables included the Health Assessment Questionnaire (HAQ), the short version of the Arthritis Impact Measurement Scales 2 (AIMS2-SF), pain and fatigue visual analogue scales (VAS), the number of comorbidities and demographic characteristics. Characteristics of patients in the maintenance and precontemplation stages of change were compared using two-sample t tests, Wilcoxon rank-sum tests and Chi-square tests. Results: Eighty nine (74%) patients were finally included in the analyses. Mean age was 58.4 (SD 11.7) years, mean RA duration was 10.1 (9.8) years and mean DAS28 was 2.8 (1.2). The distribution of exercise stages of change was as follows: precontemplation (n_30, 34%), contemplation (n_11, 13%), preparation (n_5, 6%), action (n_2, 2%), and maintenance (n_39, 45%). Compared to patients in the maintenance stage of change, precontemplators were less often at work (P_0.05), exhibited a higher body mass index (P_0.01), poorer HAQ (P_0.01), higher pain VAS (P_0.05), poorer scores of physical (P_0.001), symptom (P_0.01), affect (P_0.01) and role (P_0.01) dimensions of the AIMS2-SF, and reported less exercise benefits (P_0.05) and more barriers to exercise (p_0.01). Most participants preferred exercising alone (40%), at home (29%), at a moderate intensity (64%), with advice provided by a rheumatologist (34%) or a specialist in exercise and RA (34%). Walking was by far the preferred type of exercise, in both the summer (86%) and the winter (51%). Conclusion: This study provides new insight into how RA interferes with exercise participation. Our cohort of patients with RA was essentially distributed across the precontemplation and maintenance exercise stages of change. These subgroups of patients exhibit psychological and functional differences that make their needs in terms of exercise counseling different. Walking appears to be a simple but promising way of promoting physical activity among RA patients.
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Streptococcus pneumoniae is a leading cause of pneumonia, meningitis, and sepsis. Pneumococci can be divided into >90 serotypes that show differences in the pathogenicity and invasiveness. We tested the hypotheses that the innate immune inflammasome pathway is involved in fighting pneumococcal pneumonia and that some invasive pneumococcal types are not recognized by this pathway. We show that human and murine mononuclear cells responded to S. pneumoniae expressing hemolytic pneumolysin by producing IL-1β. This IL-1β production depended on the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome. Some serotype 1, serotype 8, and serotype 7F bacteria, which have previously been associated with increased invasiveness and with production of toxins with reduced hemolytic activity, or bacterial mutants lacking pneumolysin did not stimulate notable IL-1β production. We further found that NLRP3 was beneficial for mice during pneumonia caused by pneumococci expressing hemolytic pneumolysin and was involved in cytokine production and maintenance of the pulmonary microvascular barrier. Overall, the inflammasome pathway is protective in pneumonia caused by pneumococci expressing hemolytic toxin but is not activated by clinically important pneumococcal sequence types causing invasive disease. The study indicates that a virulence factor polymorphism may substantially affect the recognition of bacteria by the innate immune system.
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Correlative fluorescence and electron microscopy has become an indispensible tool for research in cell biology. The integrated Laser and Electron Microscope (iLEM) combines a Fluorescence Microscope (FM) and a Transmission Electron Microscope (TEM) within one set-up. This unique imaging tool allows for rapid identification of a region of interest with the FM, and subsequent high resolution TEM imaging of this area. Sample preparation is one of the major challenges in correlative microscopy of a single specimen; it needs to be apt for both FM and TEM imaging. For iLEM, the performance of the fluorescent probe should not be impaired by the vacuum of the TEM. In this technical note, we have compared the fluorescence intensity of six fluorescent probes in a dry, oxygen free environment relative to their performance in water. We demonstrate that the intensity of some fluorophores is strongly influenced by its surroundings, which should be taken into account in the design of the experiment. Furthermore, a freeze-substitution and Lowicryl resin embedding protocol is described that yields excellent membrane contrast in the TEM but prevents quenching of the fluorescent immuno-labeling. The embedding protocol results in a single specimen preparation procedure that performs well in both FM and TEM. Such procedures are not only essential for the iLEM, but also of great value to other correlative microscopy approaches.
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SUMMARY : The recognition by recipient T cells of the allograft major histocompatibility complex (MHC)mismatched antigens is the primary event that ultimately leads to rejection. In the transplantation setting, circulating alloreactive CD4+ T cells play a central role in the initiation and the coordination of the immune response and can initiate the rejection of an allograft via three distinct pathways: the direct, indirect and the recently described semi-direct pathway. However, the exact role of individual CD4+ T-cell subsets in the development of allograft rejection is not clearly defined. Furthermore, besides pathogenic effector T cells, a new subset of T cells with regulatory properties, the CD4+CD25+Foxp3+ (Treg) cells, has come under increased scrutiny over the last decade. The experiments presented in this thesis were designed to better define the phenotype and functional characteristics of CD4+ T-cell subsets and Treg cells in vitro and in vivo in a marine adoptive transfer and skin transplantation model. As Treg cells play a key role in the induction and maintenance of peripheral transplantation tolerance, we have explored whether donor-antigen specific Treg cells could be expanded in vitro. Here we describe a robust protocol for the ex-vivo generation and expansion of antigen-specific Treg cells, without loss of their characteristic phenotype and suppressive function. In our in vivo transplantation model, antigen-specific Treg cells induced donor-specific tolerance to skin allografts in lymphopenic recipients and significantly delayed skin graft rejection in wild-type mice in the absence of any other immunosuppression. Naïve and memory CD4+ T cells have distinct phenotypes, effector functions and in vivo homeostatsis, and thus may play different roles in anti-donor immunity after transplantation. We have analyzed in vitro and in vivo primary alloresponses of naïve and cross-reactive memory CD4+ T cells. We found that the CD4+CD45RBlo memory T-cell pool was heterogeneous and contained cells with regulatory potentials, both in the CD4+CD25+ and CD4+CD25- populations. CD4+ T cells capable of inducing strong primary alloreactive responses in vitro and rejection of a first allograft in vivo were mainly contained within the CD45RBhi naïve CD4+ T-cell compartment. Taken together, the work described in this thesis provides new insights into the mechanisms that drive allograft rejection or donor-specific transplantation tolerance. These results will help to optimise current clinical immunosuppressive regimens used after solid organ transplantation and design new immunotherapeutic strategies to prevent transplant rejection. RÉSUMÉ : ROLE DES SOUS-POPULATIONS DE CELLULES T DANS LE REJET DE GREFFE ET L'INDUCTION DE TOLERANCE EN TRANSPLANTATION La reconnaissance par les cellules T du receveur des alloantigènes du complexe majeur d'histocompatibilité (CMIT) présentés par une greffe allogénique, est le premier événement qui aboutira au rejet de l'organe greffé. Dans le contexte d'une transplantation, les cellules alloréactives T CD4+ circulantes jouent un rôle central dans l'initiation et la coordination de 1a réponse immune, et peuvent initier le rejet par 3 voies distinctes : la voie directe, indirecte et la voie servi-directe, plus récemment décrite. Toutefois, le rôle exact des sous-populations de cellules T CD4+ dans les différentes étapes menant au rejet d'une allogreffe n'est pas clairement établi. Par ailleurs, hormis les cellules T effectrices pathogéniques, une sous-population de cellules T ayant des propriétés régulatrices, les cellules T CD4+CD25+Foxp3+ (Treg), a été nouvellement décrite et est intensément étudiée depuis environ dix ans. Les expériences présentées dans cette thèse ont été planifiées afin de mieux définir le phénotype et les caractéristiques fonctionnels des sous-populations de cellules T CD4+ et des Treg in vitro et in vivo dans un modèle marin de transfert adoptif de cellules et de transplantation de peau. Comme les cellules Treg jouent un rôle clé dans l'induction et le maintien de la tolérance périphérique en transplantation, nous avons investigué la possibilité de multiplier in vitro des cellules Treg avec spécificité antigénique pour le donneur. Nous décrivons ici un protocole reproductible pour la génération et l'expansion ex-vivo de cellules Treg avec spécificité antigénique, sans perte de leur phénotype caractéristique et de leur fonction suppressive. Dans notre modèle in vivo de transplantation de peau, ces cellules Treg pouvaient induire une tolérance spécifique vis-à-vis du donneur chez des souris lymphopéniques, et, chez des souris normales non-lymphopéniques ces Treg ont permis de retarder significativement le rejet en l'absence de tout traitement immunosuppresseur. Les cellules T CD4+ naïves et mémoires se distinguent par leur phénotype, fonction effectrice et leur homéostasie in vivo, et peuvent donc moduler différemment la réponse immune contre le donneur après transplantation. Nous avons analysé in vitro et in vivo les réponses allogéniques primaires de cellules T CD4+ naïves et mémoires non-spécifiques (cross-réactives). Nos résultats ont montré que le pool de cellules T CD4+CD45RB'° mémoires était hétérogène et contenait des cellules avec un potentiel régulateur, aussi bien parmi la sous-population de cellules CD4+CD25+ que CD4+CD25+. Les cellules T CD4+ capables d'induire une alloréponse primaire intense in vitro et le rejet d'une première allogreffe in vivo étaient essentiellement contenues dans le pool de cellules T CD4+CD45RBhi naïves. En conclusion, le travail décrit dans cette thèse amène un nouvel éclairage sur les mécanismes responsables du rejet d'une allogreffe ou de l'induction de tolérance en transplantation. Ces résultats permettront d'optimaliser les traitements immunosuppresseurs utilisés en transplantation clinique et de concevoir des nouvelles stratégies irnmuno-thérapeutiques pour prévenir le rejet de greffe allogénique.
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Currently there are no guidelines within the Manual on Uniform Traffic Control Devices (MUTCD) on construction phasing and maintenance of traffic (MOT) for retrofit construction and maintenance projects involving innovative geometric designs. The research presented in this report addressed this gap in existing knowledge by investigating the state of the practice of construction phasing and MOT for several types of innovative geometric designs including the roundabout, single point urban interchange (SPUI), diverging diamond interchange (DDI), restricted-crossing left turn (RCUT), median U-turn (MUT), and displaced left turn (DLT). This report provides guidelines for transportation practitioners in developing construction phasing and MOT plans for innovative geometric designs. This report includes MOT Phasing Diagrams to assist in the development of MOT strategies for innovative designs. The MOT Phasing Diagrams were developed through a review of literature, survey, interviews with practitioners, and review of plans from innovative geometric design projects. These diagrams are provided as a tool to assist in improving work zone safety and mobility through construction of projects with innovative geometric designs. The aforementioned synthesis of existing knowledge documented existing practices for these types of designs.
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This booklet is a compilation of notes taken during motor grader operators workshops held at some 20 different locations throughout Iowa during the last two years. It is also the advice of 16 experienced motor grader operators and maintenance foremen (from 14 different counties around Iowa), who serve as instructors and assistant instructors at the "MoGo" workshops. The instructors have all said that they learn as much from the operators who attend the workshops as they impart. Motor grader operators from throughout Iowa have shown us new, innovative and better ways of maintaining gravel roads. This booklet is an attempt to pass on some of these "tips" that we have gathered from Iowa operators. It will need to be revised, corrected, and added to based on the advice we get from you, the operators who do the work here in Iowa.
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AbstractPlants continuously grow during their complete life span and understanding the mechanisms that qualitatively regulate their traits remains a challenging topic in biology. The hormone auxin has been identified as a crucial molecule for shaping plant growth, as it has a role in most developmental processes. In the root, the directional, so-called polar transport of auxin generates a peak of concentration that specifies and maintains the stem cell niche and a subsequent gradient of decreasing concentration that also regulates cell proliferation and differentiation. For these reasons, auxin is considered the main morphogen of the root, as it is fundamental for its organization and maintenance. Recently, in Arabidopsis thaliana, a natural variation screen allowed the discovery of BREVIS RADIX (BRX) gene as a limiting factor for auxin responsive gene expression and thus for root growth.In this study, we discovered that BRX is a direct target of auxin that positively feeds back on auxin signaling, as a transcriptional co-regulator, through interaction with the Auxin Response Factor (ARF) MONOPTEROS (MP), modulating the auxin gene response magnitude during the transition between division and differentiation in the root meristem. Moreover, we provide evidence that BRX is activated at the plasma membrane level as an associated protein before moving into the nucleus to modulate cellular growth.To investigate the discrepancy between the auxin concentration and the expression pattern of its downstream targets, we combined experimental and computational approaches. Expression profiles deviating from the auxin gradient could only be modeled after intersection of auxin activity with the observed differential endocytosis pattern and with positive auto- regulatory feedback through plasma- membrane-to-nucleus transfer of BRX. Because BRX is required for expression of certain auxin response factor targets, our data suggest a cell-type-specific endocytosis-dependent input into transcriptional auxin perception. This input sustains expression of a subset of auxin-responsive genes across the root meristem's division and transition zones and is essential for meristem growth. Thus, the endocytosis pattern provides specific positional information to modulate auxin response. RésuméLes plantes croissent continuellement tout au long de leur cycle de vie. Comprendre et expliquer les mécanismes impliqués dans ce phénomène reste à l'heure actuelle, un défi. L'hormone auxine a été identifiée comme une molécule essentielle à la régulation de la croissance des plantes, car impliquée dans la plupart des processus développementaux. Dans la racine, le transport polaire de l'auxine, par la génération d'un pic de concentration, spécifie et maintient la niche de cellules souches, et par la génération d'un gradient de concentration, contrôle la prolifération et la différentiation cellulaire. Puisque l'auxine est essentielle pour l'organisation et la maintenance du système racinaire, il est considéré comme son principal morphogène. Récemment, dans la plante modèle, Arabidopsis thalinana, un criblage des variations génétique a permis d'identifier le gène Brevis radix (BRX) comme facteur limitant l'expression des gènes de réponse à l'auxine et par là même, la croissance de la racine.Dans ce travail, nous avons découvert que BRX est une cible direct de l'auxine qui rétroactive positivement le signalement de l'hormone, agissant ainsi comme un régulateur transcriptionnel à travers l'interaction avec la protéine Monopteros (MP) de la famille des facteurs de réponse à l'auxine (Auxin Responsive Factor, ARF), et modulant ainsi la magnitude de la réponse des gènes reliés à l'auxine durant la division et la différentiation cellulaire dans le méristème de la racine. De plus, nous fournissons des preuves que BRX est activées au niveau de la membrane plasmique, tel une protéine associée se déplaçant à l'intérieur du noyau et modulant la croissance cellulaire.Pour mener à bien l'investigation des divergences entre la concentration de l'auxine et les schémas d'expression de ses propres gènes cibles, nous avons combiné les approches expérimentales et computationnelles. Les profiles d'expressions déviant du gradient d'auxine pourraient seulement être modéliser après intersection de l'activité de l'auxine avec les schémas différentiels d'endocytose observés et les boucles de rétroaction positives et autorégulatrices par le transfert de BRX de la membrane plasmique au noyau. Puisque BRX est requis pour l'expression de certains gènes cibles des facteurs de réponse à l'auxine, nos données suggèrent une contribution dépendante d'une endocytose spécifique au type de cellule dans la perception transcriptionnelle à l'auxine Cette contribution soutient l'expression d'un sous-set de gène de réponse à l'auxine dans la division du méristème racinaire et la zone de transition, et par conséquent, est essentielle pour la croissance méristematique. Ainsi, le schéma d'endocytose fournit des informations positionnelles spécifiques à la modulation de la réponse à l'auxine.
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Despite earlier diagnosis and advancements in treatment, cancer remains a leading cause of death in the world (13% of all deaths according to the World Health Organization) among men and women. Cancer accounts for approximately 20% of the deaths in the USA every year. Here, we report the findings from a cross-sectional survey of psychosocial factors in lung and gastrointestinal cancer patients. The aim of the study was to explore the associations among transitoriness, uncertainty, and locus of control (LOC) with quality of life. Transitoriness is defined as a person's confrontation with life's finitude due to a cancer diagnosis. A total of 126 patients with lung or gastrointestinal cancer completed eight self-reporting questionnaires addressing demographics, spiritual perspective, symptom burden, transitoriness, uncertainty, LOC, and quality of life. Transitoriness, uncertainty, and LOC were significantly associated with one another (r = 0.3267, p = 0.0002/r = 0.1994, p = 0.0252, respectively). LOC/belief in chance has a significant inverse relationship with patients' quality of life (r = -0.2505, p = 0.0047). Transitoriness, uncertainty, and LOC were found to have a significant inverse relationship with patients' quality of life (transitoriness state: r = -0.5363, p = 0.0000/trait: r = -0.4629, p = 0.0000/uncertainty: r = -0.4929, p = 0.0000/internal LOC: r = 0.1759, p = 0.0489/chance LOC: r = -0.2505, p = 0.0047). Transitoriness, uncertainty, and LOC are important concepts as they adversely influence patients' quality of life. Incorporating this finding into the care of cancer patients may provide them with the support they need to cope with treatment and maintenance of a positive quality of life.
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Peer-reviewed
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Työssä tutkittiin kunnossapidon mahdollisuuksia vaikuttaa laitoksen elinkaareen ja elinkaaren aikaisiin kustannuksiin. Lisäksi tutkittiin teknisen suunnittelun vaikutusta kunnossapidettävyyteen ja laitoksen elinkaarikustannuksiin. Työn kirjallisuusosassa on tarkasteltu nykyaikaisia kunnossapidon menetelmiä.Erityisesti on tutkittu luotettavuuskeskeistä kunnossapitoa ja kunnossapidon tehtäviä laitoksen elinkaaren aikana. Investoinnin laitevalinnoilla ja niiden suunnittelulla on myös merkittävä vaikutus käyttöön ja erityisesti kunnossapitoon. Työn empiirisessä osassa selvitettiin Botnia Mill Servicen jaMetsä - Botnian toimintamalleja Joutsenon sellutehtaalla. Erityisesti keskityttiin suuriin korjauksiin ja niiden kustannusten hallintaan. Myös kunnossapidon toimintamallia ja sen kehittämistä on tutkittu. Kokeellisessa osassa selvitettiin kunnossapidolle tyypillinen toimintamalli laitoksen elinkaaren hallintaa varten. Tehdyn selvityksen pohjalta voidaan todeta, että pitkän tähtäimen suunnittelu luo pohjaa kustannusten hallinnalle ja laitteiden kunnon ylläpidolle. Suunnittelun aikajänne tulisi olla laitteiden kunnostusten osalta vähintään kolme vuotta. Koko laitoksen kattava elinkaarisuunnitelma on hyvä laatia joheti käyttöönottovaiheen jälkeen. Pitkäjänteisellä suunnittelulla ja sen toteutuksella pystytään parhaalla mahdollisella tavalla ylläpitämään käyttöomaisuuden arvo. Kunnossapidolla on mahdollisuus vaikuttaa laitoksen käyttöomaisuuden arvonylläpitoon hallitsemalla elinkaarikustannuksia. Kunnossapidon onnistuneen toteutuksen takaa oikeanlainen johtaminen ja jatkuva osaamisen ylläpito. Myös kunnossapidossa sovitut toimintamallit ja järjestelmien jatkuva ylläpito ja kehittäminen takaavat onnistuneen toiminnan.
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Although canonical Notch signaling regulates multiple hematopoietic lineage decisions including T cell and marginal zone B cell fate specification, the downstream molecular mediators of Notch function are largely unknown. We showed here that conditional inactivation of Hes1, a well-characterized Notch target gene, in adult murine bone marrow (BM) cells severely impaired T cell development without affecting other Notch-dependent hematopoietic lineages such as marginal zone B cells. Competitive mixed BM chimeras, intrathymic transfer experiments, and in vitro culture of BM progenitors on Delta-like-expressing stromal cells further demonstrated that Hes1 is required for T cell lineage commitment, but dispensable for Notch-dependent thymocyte maturation through and beyond the beta selection checkpoint. Furthermore, our data strongly suggest that Hes1 is essential for the development and maintenance of Notch-induced T cell acute lymphoblastic leukemia. Collectively, our studies identify Hes1 as a critical but context-dependent mediator of canonical Notch signaling in the hematopoietic system.