840 resultados para through pores formation


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Abstract : Since at least the 1980's, a growing number of companies have set up an ethics or a compliance program within their organization. However, in the field of study of business management, there is a paucity of research studies concerning these management systems. This observation warranted the present investigation of one company's compliance program. Compliance programs are set up so that individuals working within an organization observe the laws and regulations which pertain to their work. This study used a constructivist grounded theory methodology to examine the process by which a specific compliance program, that of Siemens Canada Limited, was implemented throughout its organization. In conformity with this methodology, instead of proceeding with the investigation in accordance to a particular theoretical framework, the study established a number of theoretical constructs used strictly as reference points. The study's research question was stated as: what are the characteristics of the process by which Siemens' compliance program integrated itself into the existing organizational structure and gained employee acceptance? Data consisted of documents produced by the company and of interviews done with twenty-four managers working for Siemens Canada Limited. The researcher used QSR-Nvivo computer assisted software to code transcripts and to help with analyzing interviews and documents. Triangulation was done by using a number of analysis techniques and by constantly comparing findings with extant theory. A descriptive model of the implementation process grounded in the experience of participants and in the contents of the documents emerged from the data. The process was called "Remolding"; remolding being the core category having emerged. This main process consisted of two sub-processes identified as "embedding" and "appraising." The investigation was able to provide a detailed account of the appraising process. It identified that employees appraised the compliance program according to three facets: the impact of the program on the employee's daily activities, the relationship employees have with the local compliance organization, and the relationship employees have with the corporate ethics identity. The study suggests that a company who is entertaining the idea of implementing a compliance program should consider all three facets. In particular, it suggests that any company interested in designing and implementing a compliance program should pay particular attention to its corporate ethics identity. This is because employee's acceptance of the program is influenced by their comparison of the company's ethics identity to their local ethics identity. Implications of the study suggest that personnel responsible for the development and organizational support of a compliance program should understand the appraisal process by which employees build their relationship with the program. The originality of this study is that it points emphatically that companies must pay special attention in developing a corporate ethics identify which is coherent, well documented and well explained.

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Résumé : La maladie osseuse de Paget (MP) est un désordre squelettique caractérisé par une augmentation focale et désorganisée du remodelage osseux. Les ostéoclastes (OCs) de MP sont plus larges, actifs et nombreux, en plus d’être résistants à l’apoptose. Même si la cause précise de la MP demeure inconnue, des mutations du gène SQSTM1, codant pour la protéine p62, ont été décrites dans une proportion importante de patients avec MP. Parmi ces mutations, la substitution P392L est la plus fréquente, et la surexpression de p62P392L dans les OCs génère un phénotype pagétique partiel. La protéine p62 est impliquée dans de multiples processus, allant du contrôle de la signalisation NF-κB à l’autophagie. Dans les OCs humains, un complexe multiprotéique composé de p62 et des kinases PKCζ et PDK1 est formé en réponse à une stimulation par Receptor Activator of Nuclear factor Kappa-B Ligand (RANKL), principale cytokine impliquée dans la formation et l'activation des OCs. Nous avons démontré que PKCζ est impliquée dans l’activation de NF-κB induite par RANKL dans les OCs, et dans son activation constitutive en présence de p62P392L. Nous avons également observé une augmentation de phosphorylation de Ser536 de p65 par PKCζ, qui est indépendante d’IκB et qui pourrait représenter une voie alternative d'activation de NF-κB en présence de la mutation de p62. Nous avons démontré que les niveaux de phosphorylation des régulateurs de survie ERK et Akt sont augmentés dans les OCs MP, et réduits suite à l'inhibition de PDK1. La phosphorylation des substrats de mTOR, 4EBP1 et la protéine régulatrice Raptor, a été évaluée, et une augmentation des deux a été observée dans les OCs pagétiques, et est régulée par l'inhibition de PDK1. Également, l'augmentation des niveaux de base de LC3II (associée aux structures autophagiques) observée dans les OCs pagétiques a été associée à un défaut de dégradation des autophagosomes, indépendante de la mutation p62P392L. Il existe aussi une réduction de sensibilité à l’induction de l'autophagie dépendante de PDK1. De plus, l’inhibition de PDK1 induit l’apoptose autant dans les OCs contrôles que pagétiques, et mène à une réduction significative de la résorption osseuse. La signalisation PDK1/Akt pourrait donc représenter un point de contrôle important dans l’activation des OCs pagétiques. Ces résultats démontrent l’importance de plusieurs kinases associées à p62 dans la sur-activation des OCs pagétiques, dont la signalisation converge vers une augmentation de leur survie et de leur fonction de résorption, et affecte également le processus autophagique.

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Decisions made and actions taken by individuals in the operations function impact the formation of a company’s manufacturing strategy (MS). Therefore, it is important that the MS is understood and agreed on by all employees, that is, strategic consensus among the individuals in the operations function is essential. This research contributes to the current body of knowledge by including a workers’ perspective on MS formation. It is the workers on the shop floor who bring the MS to life in the actual operations through their daily decisions and actions. The MS falls short if the priorities outlined do not materialise in practice as intended. The purpose of this research is to investigate how the individuals in the operations function perceive the MS in order to understand how these individuals are involved in the MS formation. The research is based on five studies, differing by evidence, as follows: one theoretical, three qualitative in the setting of small and medium-sized enterprises (SMEs), and one quantitative at a large company. Based on the findings presented in the six appended papers, the results show that empirically and conceptually, workers have been overlooked or given a passive role in the MS formation. Empirically, it is seen that workers and managers do not have a shared understanding of the underlying reasons for strategic priorities; hence, the level of strategic consensus is low. Furthermore, the level of strategic consensus varies among the different MS dimensions depending on their organisational level. Moreover, the empirical findings reveal that internal contextual factors influence the individuals’ perceptions of the MS and the possibilities for strategic consensus. Regarding the external context, the results show that major customers’ strategies influence the subcontractor SMEs’ MS formation. The usage of means of communication in the operations function has also shown to be of importance for how the MS is perceived. Conceptually, the findings indicate that the MS literature tends to treat individuals in the operations function in a deterministic manner; individuals on the shop floor are regarded as manufacturing resources. To ensure a successful MS formation process, where the patterns of the decisions made by the individuals in the operations function forms the MS, the view on human nature within the MS requires a more voluntaristic approach. This research suggests to view the MS formation as an iterative “patterning process” which builds on a reciprocal relationship between workers and managers. The introduction of the patterning process contributes to the research on MS formation by explaining the perception range within the hierarchical levels, by re-defining the hierarchical levels included in the MS formation and by detailing the activities in the MS formation.

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The emergence and dissemination of multi-drug resistant pathogens is a global concern. Moreover, even greater levels of resistance are conferred on bacteria when in the form of biofilms (i.e., complex, sessile communities of bacteria embedded in an organic polymer matrix). For decades, antimicrobial peptides have been hailed as a potential solution to the paucity of novel antibiotics, either as natural inhibitors that can be used alone or in formulations with synergistically acting antibiotics. Here, we evaluate the potential of the antimicrobial peptide nisin to increase the efficacy of the antibiotics polymyxin and colistin, with a particular focus on their application to prevent biofilm formation of Pseudomonas aeruginosa. The results reveal that the concentrations of polymyxins that are required to effectively inhibit biofilm formation can be dramatically reduced when combined with nisin, thereby enhancing efficacy, and ultimately, restoring sensitivity. Such combination therapy may yield added benefits by virtue of reducing polymyxin toxicity through the administration of significantly lower levels of polymyxin antibiotics.

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For SMEs to operate in the complex and globalised economic landscape of today engaging with innovation can sustain competitive advantage. Within Design Management, design is being increasingly posited as a strategic resource to facilitate the absorption of new design resources and leverage design knowledge in ways that support SMEs through such economic pressures. Evidencing the relationship between design and economic performance is complex, leading to extensive current research and industry efforts to show how design adds economic value. Despite the value of such efforts, it is important to recognise that innovation means different things to different organizations, especially for start-ups and SMEs. Within the rising tide of design-led innovation, there is a gap being explored in how design can effectively capture and evaluate its contribution within the complex and diverse situations of business development it engages. In seeking to address this gap, this paper presents findings from research undertaken within Design in Action (DiA), an AHRC-funded knowledge exchange hub. Presenting DiA as a single case study, the paper offers methodical reflection on five case example start-up businesses funded by DiA in order to explore the value that design-led innovation approaches offered in their formation.

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Hybrid halide perovskites have emerged as promising active constituents of next generation solution processable optoelectronic devices. During their assembling process, perovskite components undergo very complex dynamic equilibria starting in solution and progressing throughout film formation. Finding a methodology to control and affect these equilibria, responsible for the unique morphological diversity observed in perovskite films, constitutes a fundamental step towards a reproducible material processability. Here we propose the exploitation of polymer matrices as cooperative assembling components of novel perovskite CH3NH3PbI3 : polymer composites, in which the control of the chemical interactions in solution allows a predictable tuning of the final film morphology. We reveal that the nature of the interactions between perovskite precursors and polymer functional groups, probed by Nuclear Magnetic Resonance (NMR) spectroscopy and Dynamic Light Scattering (DLS) techniques, allows the control of aggregates in solution whose characteristics are strictly maintained in the solid film, and permits the formation of nanostructures that are inaccessible to conventional perovskite depositions. These results demonstrate how the fundamental chemistry of perovskite precursors in solution has a paramount influence on controlling and monitoring the final morphology of CH3NH3PbI3 (MAPbI3) thin films, foreseeing the possibility of designing perovskite : polymer composites targeting diverse optoelectronic applications.

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Language provides an interesting lens to look at state-building processes because of its cross-cutting nature. For example, in addition to its symbolic value and appeal, a national language has other roles in the process, including: (a) becoming the primary medium of communication which permits the nation to function efficiently in its political and economic life, (b) promoting social cohesion, allowing the nation to develop a common culture, and (c) forming a primordial basis for self-determination. Moreover, because of its cross-cutting nature, language interventions are rarely isolated activities. Languages are adopted by speakers, taking root in and spreading between communities because they are legitimated by legislation, and then reproduced through institutions like the education and military systems. Pádraig Ó’ Riagáin (1997) makes a case for this observing that “Language policy is formulated, implemented, and accomplishes its results within a complex interrelated set of economic, social, and political processes which include, inter alia, the operation of other non-language state policies” (p. 45). In the Turkish case, its foundational role in the formation of the Turkish nation-state but its linkages to human rights issues raises interesting issues about how socio-cultural practices become reproduced through institutional infrastructure formation. This dissertation is a country-level case study looking at Turkey’s nation-state building process through the lens of its language and education policy development processes with a focus on the early years of the Republic between 1927 and 1970. This project examines how different groups self-identified or were self-identified (as the case may be) in official Turkish statistical publications (e.g., the Turkish annual statistical yearbooks and the population censuses) during that time period when language and ethnicity data was made publicly available. The overarching questions this dissertation explores include: 1.What were the geo-political conditions surrounding the development and influencing the Turkish government’s language and education policies? 2.Are there any observable patterns in the geo-spatial distribution of language, literacy, and education participation rates over time? In what ways, are these traditionally linked variables (language, literacy, education participation) problematic? 3.What do changes in population identifiers, e.g., language and ethnicity, suggest about the government’s approach towards nation-state building through the construction of a civic Turkish identity and institution building? Archival secondary source data was digitized, aggregated by categories relevant to this project at national and provincial levels and over the course of time (primarily between 1927 and 2000). The data was then re-aggregated into values that could be longitudinally compared and then layered on aspatial administrative maps. This dissertation contributes to existing body of social policy literature by taking an interdisciplinary approach in looking at the larger socio-economic contexts in which language and education policies are produced.

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Constantly making efforts to strengthen reading habits in children from their earliest years of life, a process in which the family is established as the primary basis for the child to achieve the taste and interest in books. The school as being key to education supports and strengthens the skills taught in the home, with the help of technologies such as computers, disk reading, television, among other means, by which (as) children (as) found a door of communication with the outside world and everything around them. The children's library tends to use these technological means to attract children to reading, generating and taste for the various information resources, which over time will become a habit.This research is based on the "Contribution of the Library Miriam Alvarez Brenes and family in the formation of reading habits of children of the community of Garden I and II University in Heredia, through advocacy, in 2007 "

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Abstract: The serrated pathway to colorectal tumor formation involves oncogenic mutations in the BRAF gene, which are sufficient for initiation of hyperplastic growth but not for tumor progression. A previous analysis of colorectal tumors revealed that overexpression of splice variant Rac1b occurs in around 80% of tumors with mutant BRAF and both events proved to cooperate in tumor cell survival. Patients with inflamed human colonic mucosa also have increased expression of Rac1b as well as mice with experimentally induced colitis. The increase of Rac1b in the mouse model was specifically prevented by the nonsteroidal anti-inflammatory drug ibuprofen. Purpose: The objective of our study is to understand the molecular regulation of Rac1b alternative splicing event and how it contributes to tumorigenesis. Experimental description: HT29 colorectal cell line was used as model to test several signaling pathways after 48h of treatment with ibuprofen. For this we analyzed the proteins of interest by Western Blot and the transcript levels by RT-PCR. Results: Mechanistic studies in cultured HT29 colorectal tumor cells revealed that ibuprofen inhibited Rac1b expression in a cyclooxygenase inhibition–independent manner and targets directly the alternative splicing event. Here, we provide evidence that ibuprofen leads to a decrease in expression of SRSF1, a splicing factor that we previously identified to promote Rac1b alternative splicing. Together, our results suggest that stromal cues, namely, inflammation, can trigger changes in Rac1b expression in the colon and identify ibuprofen as a highly specific and efficient inhibitor of Rac1b overexpression in colorectal tumors. Conclusions: Our data identify an additional cyclooxygenase–independent action of ibuprofen and suggest it may be beneficial in the treatment of patients with the subtype of BRAF-mutated serrated colorectal tumors.

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Introduction: The serrated pathway to colorectal tumor formation involves oncogenic mutations in the BRAF gene, which are sufficient for initiation of hyperplastic growth but not for tumor progression. A previous analysis of colorectal tumors revealed that overexpression of splice variant Rac1b occurs in around 80% of tumors with mutant BRAF and both events proved to cooperate in tumor cell survival. Patients with inflamed human colonic mucosa also have increased expression of Rac1b as well as mice with experimentally induced colitis. The increase of Rac1b in the mouse model was specifically prevented by the nonsteroidal anti-inflammatory drug ibuprofen.

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A l’heure actuelle, les biocarburants renouvelables et qui ne nuit pas à l'environnement sont à l'étude intensive en raison de l'augmentation des problèmes de santé et de la diminution des combustibles fossiles. H2 est l'un des candidats les plus prometteurs en raison de ses caractéristiques uniques, telles que la densité d'énergie élevée et la génération faible ou inexistante de polluants. Une façon attrayante pour produire la H2 est par les bactéries photosynthétiques qui peuvent capter l'énergie lumineuse pour actionner la production H2 avec leur système de nitrogénase. L'objectif principal de cette étude était d'améliorer le rendement de H2 des bactéries photosynthétiques pourpres non sulfureuses utilisant une combinaison de génie métabolique et le plan des expériences. Une hypothèse est que le rendement en H2 pourrait être améliorée par la redirection de flux de cycle du Calvin-Benson-Bassham envers du système de nitrogénase qui catalyse la réduction des protons en H2. Ainsi, un PRK, phosphoribulose kinase, mutant « knock-out » de Rhodobacter capsulatus JP91 a été créé. L’analyse de la croissance sur des différentes sources de carbone a montré que ce mutant ne peut croître qu’avec l’acétate, sans toutefois produire d' H2. Un mutant spontané, YL1, a été récupéré qui a retenu l'cbbP (codant pour PRK) mutation d'origine, mais qui avait acquis la capacité de se développer sur le glucose et produire H2. Une étude de la production H2 sous différents niveaux d'éclairage a montré que le rendement d’YL1 était de 20-40% supérieure à la souche type sauvage JP91. Cependant, il n'y avait pas d'amélioration notable du taux de production de H2. Une étude cinétique a montré que la croissance et la production d'hydrogène sont fortement liées avec des électrons à partir du glucose principalement dirigés vers la production de H2 et la formation de la biomasse. Sous des intensités lumineuses faibles à intermédiaires, la production d'acides organiques est importante, ce qui suggère une nouvelle amélioration additionnel du rendement H2 pourrait être possible grâce à l'optimisation des processus. Dans une série d'expériences associées, un autre mutant spontané, YL2, qui a un phénotype similaire à YL1, a été testé pour la croissance dans un milieu contenant de l'ammonium. Les résultats ont montré que YL2 ne peut croître que avec de l'acétate comme source de carbone, encore une fois, sans produire de H2. Une incubation prolongée dans les milieux qui ne supportent pas la croissance de YL2 a permis l'isolement de deux mutants spontanés secondaires intéressants, YL3 et YL4. L'analyse par empreint du pied Western a montré que les deux souches ont, dans une gamme de concentrations d'ammonium, l'expression constitutive de la nitrogénase. Les génomes d’YL2, YL3 et YL4 ont été séquencés afin de trouver les mutations responsables de ce phénomène. Fait intéressant, les mutations de nifA1 et nifA2 ont été trouvés dans les deux YL3 et YL4. Il est probable qu'un changement conformationnel de NifA modifie l'interaction protéine-protéine entre NifA et PII protéines (telles que GlnB ou GlnK), lui permettant d'échapper à la régulation par l'ammonium, et donc d'être capable d'activer la transcription de la nitrogénase en présence d'ammonium. On ignore comment le nitrogénase synthétisé est capable de maintenir son activité parce qu’en théorie, il devrait également être soumis à une régulation post-traductionnelle par ammonium. Une autre preuve pourrait être obtenue par l'étude du transcriptome d’YL3 et YL4. Une première étude sur la production d’ H2 par YL3 et YL4 ont montré qu'ils sont capables d’une beaucoup plus grande production d'hydrogène que JP91 en milieu d'ammonium, qui ouvre la porte pour les études futures avec ces souches en utilisant des déchets contenant de l'ammonium en tant que substrats. Enfin, le reformage biologique de l'éthanol à H2 avec la bactérie photosynthétique, Rhodopseudomonas palustris CGA009 a été examiné. La production d'éthanol avec fermentation utilisant des ressources renouvelables microbiennes a été traitée comme une technique mature. Cependant, la plupart des études du reformage de l'éthanol à H2 se sont concentrés sur le reformage chimique à la vapeur, ce qui nécessite généralement une haute charge énergetique et résultats dans les émissions de gaz toxiques. Ainsi le reformage biologique de l'éthanol à H2 avec des bactéries photosynthétiques, qui peuvent capturer la lumière pour répondre aux besoins énergétiques de cette réaction, semble d’être plus prometteuse. Une étude précédente a démontré la production d'hydrogène à partir d'éthanol, toutefois, le rendement ou la durée de cette réaction n'a pas été examiné. Une analyse RSM (méthode de surface de réponse) a été réalisée dans laquelle les concentrations de trois facteurs principaux, l'intensité lumineuse, de l'éthanol et du glutamate ont été variés. Nos résultats ont montré que près de 2 moles de H2 peuvent être obtenus à partir d'une mole d'éthanol, 33% de ce qui est théoriquement possible.

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The effluents released by the textile industry have high concentrations of alkali, carbohydrates, proteins, in addition to colors containing heavy metals. Therefore, a filter was prepared aiming primarily to the removal of color. In order to prepare this filter, rice hulls and diatomite were used, which have in their structure, basically amorphous hydrated silica. The silica exists in three crystalline forms: quartz, tridymite and cristobalite. In accordance with the above considerations, this study was divided into two stages; the first corresponds to the preparation of the filter and the second to carry out the tests in the effluent/filter in order to verify the efficiency of the color removal. First, the raw material was subjected to a chemical analysis and XRD, and then the diatomite was mixed, via humid, with a planetarium windmill with 20 %, 40 %, 60 % and 80 % of rice husk ash. To the mixture, 5 % carboxymethylcellulose (CMC) was added as a binder at room temperature. The samples were uniaxially compacted into metallic matrix of 0.3 x 0.1 cm² of area at a pressure of 167 MPa by means of hydraulic press and then sintered at temperatures of 1,000 °C, 1,200 °C and 1,400 °C for 1 h and submitted to granulometry test using laser, linear retraction, water absorption, apparent porosity and resistance to bending, DTA, TMA and XRD. To examine the pore structure of the samples scanning electron microscope (SEM) was used. Also tests were carried out in a mercury porosimeter to verify the average size of the pores and real density of the samples. In the second stage, samples of the effluent were collected from a local industry, whose name will be preserved, located in Igapó, in the State of Rio Grande do Norte - RN. The effluent was first pretreated before filtration and then subjected to a treatment of flotation. The effluent was then characterized before and after filtration, with parameters of color, turbidity, suspended solids, pH, chemical and biochemical oxygen demand (COD and BOD). Thus, through the XRD analysis the formation of cristobalite α in all samples was observed. The best average size of pore was found to be 1.75 μm with 61.04 % apparent porosity, thus obtaining an average 97.9 % color removal and 99.8 % removal of suspended solid

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Despite the efforts to better manage biosolids field application programs, biosolids managers still lack of efficient and reliable tools to apply large quantities of material while avoiding odor complaints. Objectives of this research were to determine the capabilities of an electronic nose in supporting process monitoring of biosolids production and, to compare odor characteristics of biosolids produced through thermal-hydrolysis anaerobic digestion (TH-AD) to those of alkaline stabilization in the plant, under storage and in the field. A method to quantify key odorants was developed and full scale sampling and laboratory simulations were performed. The portable electronic nose (PEN3) was tested for its capabilities of distinguishing alkali dosages in the biosolids production process. Frequency of recognition of unknown samples was tested achieving highest accuracy of 81.1%. This work exposed the need for a different and more sensitive electronic nose to assure its applicability at full scale for this process. GC-MS results were consistent with those reported in literature and helped to elucidate the behavior of the pattern recognition of the PEN3. Odor characterization of TH-AD and alkaline stabilized biosolids was achieved using olfactometry measurements and GC-MS. Dilution-to-threshold of TH-AD biosolids increased under storage conditions but no correlation was found with the target compounds. The presence of furan and three methylated homologues in TH-AD biosolids was reported for the first time proposing that these compounds are produced during thermal hydrolysis process however, additional research is needed to fully describe the formation of these compounds and the increase in odors. Alkaline stabilized biosolids reported similar odor concentration but did not increase and the ‘fishy’ odor from trimethylamine emissions resulted in more offensive and unpleasant odors when compared to TH-AD. Alkaline stabilized biosolids showed a spike in sulfur and trimethylamine after 3 days of field application when the alkali addition was not sufficient to meet regulatory standards. Concentrations of target compounds from field application of TH-AD biosolids gradually decreased to below the odor threshold after 3 days. This work increased the scientific understanding on odor characteristics and behavior of two types of biosolids and on the application of electronic noses to the environmental engineering field.

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We have shown Galanin(GAL) and Neuropeptide Y Y1(NPYY1) interactions at behavioural, cellular and receptor levels through GALR2/NPYY1R heterodimers in the amygdala. The aim of this work was to analyze GAL/NPYY1R interactions in the Dentate Gyrus(DG) of the Hippocampus, using autoradiographic, in situ hybridization and in situ proximity ligation assay(PLA). Rats(n=6) were sacrificed 15 minutes or 5 hours after icv injections of GAL(3nmol) and DG sections were incubated with NPYY1R agonist [I125]-[Leu31,Pro34]PYY(25 pM) or NPYY1R-33PdATP specific probe, for autoradiography and in situ hybridization respectively. Autoradiograms were analyzed using NIH image analysis system and Student’s unpaired t-test was used. For PLA, DG sections were incubated with anti-GALR2 Rabbit(1:100) and anti-NPYY1R Goat(1:200). PLA signals were detected with PLA PLUS or MINUS probes for rabbit or goat/mouse antibodies. PLA signals were visualized by using a confocal microscope Leica TCS-SL confocal microscope(Leica). We observed that GAL significant increased the NPYY1R agonist [I125]-[Leu31,Pro34]PYY binding in the DG by 20% (p<0,05) and the NPYY1R mRNA expression in the granular layer of DG by 31% (p<0,001). Moreover, PLA-positive red clusters were found specifically in the polymorphic layer and subgranular zone of the DG. No PLA clusters were observed neither in the molecular layer of the DG nor in the corpus callosum, an area that seems to lack of GALR2 receptor. These results demonstrate a novel mechanism of interaction between GAL and NPY1R in the DG at receptor level, probably involving the formation of GALR2/NPYY1R heteroreceptor complexes. Study supported by Junta de Andalucia CVI6476.

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Expedient synthetic approaches to the highly functionalized polycyclic alkaloids communesin F and perophoramidine are described using a unified approach featuring a key decarboxylative allylic alkylation to access a crucial and highly congested 3,3-disubstituted oxindole. Described are two distinct, stereoselective alkylations that produce structures in divergent diastereomeric series possessing the critical vicinal all-carbon quaternary centers needed for each synthesis. Synthetic studies toward these challenging core structures have revealed a number of unanticipated modes of reactivity inherent to these complex alkaloid scaffolds. Finally, a previously unknown mild and efficient deprotection protocol for the o-nitrobenzyl group is disclosed – this serendipitous discovery permitted a concise endgame for the formal syntheses of both communesin F and perophoramidine.

In addition, the atroposelective synthesis of PINAP ligands has been accomplished via a palladium-catalyzed C–P coupling process through dynamic kinetic resolution. These catalytic conditions allow access to a wide variety of alkoxy- and benzyloxy-substituted PINAP ligands in high enantiomeric excess.

An efficient and exceptionally mild intramolecular nickel-catalyzed carbon–oxygen bond-forming reaction between vinyl halides and primary, secondary, and tertiary alcohols has been achieved. This operationally simple method allows direct access to cyclic vinyl ethers in high yields in a single step.

Finally, synthetic studies toward polycyclic ineleganolide are described. The entire fragmented carbon framework has been constructed from this work. Highly (Z)-selective olefination was achieved by the method by the Ando group.