164,186 research outputs found

    Desarrollo de papeles biocativos por injerto de mol茅culas espec铆ficas en celulosa

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    Tesis (DCI)--FCEFN-UNC, 2019En la presente tesis se presenta el desarrollo de papeles bioactivos con potencial aplicaci贸n en el envasado activo de alimentos. Para tal fin, se propuso el injerto de eugenol, un compuesto de origen natural con propiedades antimicrobiana, antioxidante y repelente de insectos, en celulosa, utilizando 谩cido policarbox铆lico como agente ligante. Con el objetivo de evaluar la escalabilidad del proceso propuesto, se estudiaron distintas tecnolog铆as de curado, tales como calentamiento por convecci贸n, infrarrojo, microondas y conducci贸n. En todos los casos, se analizaron la influencia de las variables operativas sobre el avance de la reacci贸n y propiedades finales del papel preparado, utilizando un dise帽o de experimentos Doehlert para elegir las experiencias a realizar, y analizando los resultados mediante metodolog铆a de superficie de respuesta y an谩lisis estad铆stico ANOVA. Se pudo comprobar que la reacci贸n de injerto de eugenol en papel comercial se produjo con 茅xito en todas las tecnolog铆as estudiadas. Asimismo, se encontraron las condiciones 贸ptimas de reacci贸n para cada una de las tecnolog铆as, para lo cual se busc贸 un compromiso entre el avance de la reacci贸n y las propiedades finales del material (mec谩nicas y color). A partir de estas condiciones, se prepararon papeles y se realiz贸 una caracterizaci贸n m谩s espec铆fica para su aplicaci贸n como envase de alimentos comparando los papeles modificados con el papel virgen. Se analizaron las propiedades mec谩nicas por ensayo de tracci贸n, rasgado y punzonado y se midi贸 la absorci贸n de agua y la capacidad de degradaci贸n. Por otro lado, las propiedades bioactivas analizadas fueron la actividad antioxidante, antimicrobiana, repelente e insecticida de gorgojos (T. castaneum y R. dominica). Una vez probado que el papel modificado presenta buenas caracter铆sticas f铆sicas y bioactivas para su posible aplicaci贸n en el envasado de alimentos, se realizaron prototipos de envasado para harina, como alimento representativo de alimentos derivados de cereales, susceptibles al ataque de plagas. En este estudio se analiz贸 la migraci贸n de reactivos, propiedades organol茅pticas y conservaci贸n del alimento, arrojando resultados promisorios para la industria de envases de alimentos. Finalmente, se realiz贸 una comparaci贸n de las tecnolog铆as de curado ensayadas, analizando diferentes aspectos como avance de reacci贸n, propiedades finales, apariencia, tiempo de reacci贸n, consumo de energ铆a, entre otros, como as铆 tambi茅n disponibilidad y uso de estas tecnolog铆as a escala industrial, seleccionando la tecnolog铆a de conducci贸n como la m谩s adecuada para una propuesta de escalado industrial.Fil: Muratore, Florencia. Universidad Nacional de C贸rdoba. Facultad de Ciencias Exactas, F铆sicas y Naturales; Argentina.Fil: Muratore, Florencia. Consejo Nacional de Investigaciones Cient铆ficas y T茅cnicas. Instituto de Investigaci贸n y Desarrollo en Ingenier铆a de Procesos y Qu铆mica Aplicada; Argentina

    Does international patent collaboration have an effect on entrepreneurship?

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    .Entrepreneurship is one of the main pillars of growth in any economy. Achieving a high rate of entrepreneurship in a region has become the priority objective of governments and firms. However, in many cases, new firm creation is conditioned by relations or collaboration in innovation with agents from other countries. Previous literature has analyzed the mechanisms that foster entrepreneurship. This paper attempts to shed light on the influence of international patent collaboration (IPC) on entrepreneurial activity at country level taking into account the timing of this relationship. An empirical study is proposed to verify whether IPC leads to greater entrepreneurship and to analyze the gestation period between international patenting actions and firm creation. Using the Generalized Method of Moments, the two hypotheses proposed were tested in a data panel of 30 countries for the period 2005鈥2017. Results show the influence of IPC in promoting entrepreneurship in the same year, but especially in the following year. The study offers implications for entrepreneurs and public agents. IPC affects the integration and interaction of international agents in a country, favors the production of new knowledge, and increases positive externalities in a territory. All this facilitates the creation of new companies with a high innovative component.S

    Review of the Concept of wu wei (鏃犱负): Its Relationship with Anarchism and Soft Power

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    鏈枃閫氳繃瀵逛腑鍥芥枃瀛︾殑涓嶅悓鍙ゅ吀鏂囨湰鐨 鍒嗘瀽锛屾棬鍦ㄥ鈥滄棤涓衡濈殑閬撴暀瑙傚康杩涜姊 鐞嗭紝骞跺皢鍏朵綔涓洪亾鏁欑殑鏀挎不瑙傚康涓庡綋鍓嶆棤鏀 搴滀富涔夌殑鍏崇郴杩涜杩戜技鍖栥傛枃绔犺璁轰簡閬撴暀 鎬佸害鍜屽熀鏈涓轰笌棰嗗涔嬮棿鐨勫叧绯伙紝浠ュ強浠 澶╃鐞嗗浗闄呭叧绯荤殑杞疄鍔涜蹇点備簡瑙e拰鍐 鍖栤滄棤涓衡濋瀵肩殑瀹氫箟鍜屽師鍒欙紝鍙互甯姪绀 浼氬舰鎴愭洿濂界殑闈㈠鍐茬獊鐨勯瀵艰咃細鐢ㄦ洿澶氱殑 鎬濊冨拰鑰愬績锛岄氳繃閬撴暀棰嗗绠$悊鍔涢噺鍜岃蒋瀹 鍔涳紝鏉ヨ幏寰椾笘鐣岀殑骞宠 涓庡拰璋愩 Through the analysis of different classical texts of Chinese literature, this article aims to carry out a review of the Taoist concept of wu wei and to make an approximation to the relationship between Taoism鈥檚 political conception and current anarchism. The article discusses, also from this review, the links between basic behavior and Taoist attitude and leadership and the concept of soft power that govern international relations today. Getting to understand and internalize the definition and principles of leadership wu wei, could help society to form leaders who face and manage conflicts better: with more reflection and patience and achieve, with a Taoist leadership management, of its strength and of its soft power, a more balanced and harmonious world

    An谩lisis de la calidad del servicio que prestan las entidades bancarias y su repercusi贸n en la satisfacci贸n del cliente y la lealtad hacia la entidad

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    p. 79-107El objetivo de la investigaci贸n se ha encuadrado en determinar las percepciones de calidad que tienen los clientes sobre su entidad bancaria. Para ello, para contrastar el modelo se han utilizado ecuaciones estructurales por medio de m铆nimos cuadrados parciales conocido como PLS (Partial Least Square). El objetivo concreto ha sido analizar los factores que determinan la calidad del servicio que perciben los clientes de las entidades bancarias, entre los que se encuentran: i) aspecto operativo, ii) aspecto f铆sico, iii) nuevas tecnolog铆as, y iv) aspecto humano. Una vez determinada la fiabilidad y validez de la escala, se procedi贸 a verificar las tres hip贸tesis de la investigaci贸n. La primera hip贸tesis del modelo examina cada una de las relaciones de estos factores con la calidad del servicio, del que se resalta la gran influencia de los aspectos operativos en la percepci贸n de la calidad. La segunda hip贸tesis demuestra que la calidad del servicio es un antecedente de la satisfacci贸n del cliente. Y una tercera hip贸tesis verifica que la satisfacci贸n del cliente tiene influencia en la lealtad del cliente hacia la entidad.S

    La mujer en el mercado laboral = Woman in labour market

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    El estudio sometido a consideraci贸n del tribunal construye por aluvi贸n distintas im谩genes de la mujer en el mercado de trabajo. No aspira, por tanto, m谩s que a dejar una noticia hilvanada de algunos aspectos se帽eros que conducen a su postergaci贸n en la actualidad. El repaso lleva, de esta manera, a preocuparse por una formaci贸n desvinculada de los intereses empresariales, la falta de contundencia en los apoyos directos e indirectos a su contrataci贸n, los s铆ntomas profundos de precariedad bajo la forma de temporalidad, parcialidad, ausencia de corresponsabilidad o cuanto conduce a un suelo pegajoso y a un techo de cristal que confinan su realizaci贸n como personas a partir de un trabajo digno. Concluye con uno de los aspectos m谩s salientes que pudiera encontrar el jurista, como es la protecci贸n legal del proceso de gestaci贸n en todos sus momentos; en particular, por su actualidad en los 煤ltimos tiempos, la valoraci贸n por la jurisprudencia del despido de las trabajadoras embarazadas

    Application of lactic acid bacteria for the biopreservation of meat products: A systematic review

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    .The increasing concern of consumers about food quality and safety and their rejection of chemical additives has promoted the breakthrough of the biopreservation field and the development of studies on the use of beneficial bacteria and their metabolites as potential natural antimicrobials for shelf life extension and enhanced food safety. Control of foodborne pathogens in meat and meat products represents a serious challenge for the food industry which can be addressed through the intelligent use of bio-compounds or biopreservatives. This article aims to systematically review the available knowledge about biological strategies based on the use of lactic acid bacteria to control the proliferation of undesirable microorganisms in different meat products. The outcome of the literature search evidenced the potential of several strains of lactic acid bacteria and their purified or semi-purified antimicrobial metabolites as biopreservatives in meat products for achieving longer shelf life or inhibiting spoilage and pathogenic bacteria, especially when combined with other technologies to achieve a synergistic effect.S

    Identification of Hindbrain Neural Substrates for Motor Initiation in the hatchling Xenopus laevis Tadpole

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    Animal survival profoundly depends on the ability to detect stimuli in the environment, process them and respond accordingly. In this respect, motor responses to a sensory stimulation evolved into a variety of coordinated movements, which involve the control of brain centres over spinal locomotor circuits. The hatchling Xenopus tadpole, even in its embryonic stage, is able to detect external sensory information and to swim away if the stimulus is considered noxious. To do so, the tadpole relies on well-known ascending sensory pathway, which carries the sensory information to the brain. When the stimulus is strong enough, descending interneurons are activated, leading to the excitation of spinal CPG neurons, which causes the undulatory movement of swimming. However, the activation of descending interneurons that marks the initiation of motor response appears after a long delay from the sensory stimulation. Furthermore, the long-latency response is variable in time, as observed in the slow-summating excitation measured in descending interneurons. These two features, i.e. long-latency and variability, cannot be explained by the firing time and pattern of the ascending sensory pathway of the Xenopus tadpole. Therefore, a novel neuronal population has been proposed to lie in the hindbrain of the tadpole, and being able to 'hold' the sensory information, thus accounting for the long and variable delay of swim initiation. In this work, the role of the hindbrain in the maintenance of the long and variable response to trunk skin stimulation is investigated in the Xenopustadpole at developmental stage 37/38. A multifaceted approach has been used to unravel the neuronal mechanisms underlying the delayed motor response, including behavioural experiments, electrophysiology analysis of fictive swimming, hindbrain extracellular recordings and imaging experiments. Two novel neuronal populations have been identified in the tadpole's hindbrain, which exhibit activation patterns compatible with the role of delaying the excitation of the spinal locomotor circuit. Future work on cellular properties and synaptic connections of these newly discovered populations might shed light on the mechanism of descending control active at embryonic stage. Identifying supraspinal neuronal populations in an embryonic organism could aid in understanding mechanisms of descending motor control in more complex vertebrates

    Interactive Sonic Environments: Sonic artwork via gameplay experience

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    The purpose of this study is to investigate the use of video-game technology in the design and implementation of interactive sonic centric artworks, the purpose of which is to create and contribute to the discourse and understanding of its effectiveness in electro-acoustic composition highlighting the creative process. Key research questions include: How can the language of electro-acoustic music be placed in a new framework derived from videogame aesthetics and technology? What new creative processes need to be considered when using this medium? Moreover, what aspects of 'play' should be considered when designing the systems? The findings of this study assert that composers and sonic art practitioners need little or no coding knowledge to create exciting applications and the myriad of options available to the composer when using video-game technology is limited only by imagination. Through a cyclic process of planning, building, testing and playing these applications the project revealed advantages and unique sonic opportunities in comparison to other sonic art installations. A portfolio of selected original compositions, both fixed and open are presented by the author to complement this study. The commentary serves to place the work in context with other practitioners in the field and to provide compositional approaches that have been taken

    Balancing the urban stomach: public health, food selling and consumption in London, c. 1558-1640

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    Until recently, public health histories have been predominantly shaped by medical and scientific perspectives, to the neglect of their wider social, economic and political contexts. These medically-minded studies have tended to present broad, sweeping narratives of health policy's explicit successes or failures, often focusing on extraordinary periods of epidemic disease viewed from a national context. This approach is problematic, particularly in studies of public health practice prior to 1800. Before the rise of modern scientific medicine, public health policies were more often influenced by shared social, cultural, economic and religious values which favoured maintaining hierarchy, stability and concern for 'the common good'. These values have frequently been overlooked by modern researchers. This has yielded pessimistic assessments of contemporary sanitation, implying that local authorities did not care about or prioritise the health of populations. Overly medicalised perspectives have further restricted historians' investigation and use of source material, their interpretation of multifaceted and sometimes contested cultural practices such as fasting, and their examination of habitual - and not just extraordinary - health actions. These perspectives have encouraged a focus on reactive - rather than preventative - measures. This thesis contributes to a growing body of research that expands our restrictive understandings of pre-modern public health. It focuses on how public health practices were regulated, monitored and expanded in later Tudor and early Stuart London, with a particular focus on consumption and food-selling. Acknowledging the fundamental public health value of maintaining urban foodways, it investigates how contemporaries sought to manage consumption, food production waste, and vending practices in the early modern City's wards and parishes. It delineates the practical and political distinctions between food and medicine, broadly investigates the activities, reputations of and correlations between London's guild and itinerant food vendors and licensed and irregular medical practitioners, traces the directions in which different kinds of public health policy filtered up or down, and explores how policies were enacted at a national and local level. Finally, it compares and contrasts habitual and extraordinary public health regulations, with a particular focus on how perceptions of and actual food shortages, paired with the omnipresent threat of disease, impacted broader aspects of civic life

    South Yorkshire low carbon energy supply chains: insulation sector summary

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