65 research outputs found

    Influenza della velocità di deformazionenel carico di rottura di moschettoni in lega di alluminio e di acciaio

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    Si analizzano i dati sulla deformabilità, sul lavoro alla rottura e sulla resistenza ottenuti con prove di caduta a velocità di deformazione variabile (Torre CRASC) su moschettoni in lega di alluminio e in acciaio, evidenziando come all’aumentare della velocità di deformazione le caratteristiche di resistenza diminuiscano marcatamente. Queste variazioni vengono messe in relazione ai diversi intervalli dei valori della velocità di deformazione propri della progressione speleologica, torrentistica, alpinistica e ad alte velocità di deformazione (vie ferrate).We analyze data on the deformability, the work on resistance to breakage and obtained evidence of a fall in variable strain rate (Torre CRASC) on snap aluminum alloy and steel, noting that with increasing strain rate characteristics resistance decreases markedly. These changes are made in relation to the different ranges of values of strain rate of its progression caving, canyoning, mountaineering, high strain rate (via ferrata)

    The cycling of carbon into and out of dust

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    Observational evidence seems to indicate that the depletion of interstellar carbon into dust shows rather wide variations and that carbon undergoes rather rapid recycling in the interstellar medium (ISM). Small hydrocarbon grains are processed in photo-dissociation regions by UV photons, by ion and electron collisions in interstellar shock waves and by cosmic rays. A significant fraction of hydrocarbon dust must therefore be re-formed by accretion in the dense, molecular ISM. A new dust model (Jones et al., Astron. Astrophys., 2013, 558, A62) shows that variations in the dust observables in the diffuse interstellar medium (nH = 1000 cm^3), can be explained by systematic and environmentally-driven changes in the small hydrocarbon grain population. Here we explore the consequences of gas-phase carbon accretion onto the surfaces of grains in the transition regions between the diffuse ISM and molecular clouds (e.g., Jones, Astron. Astrophys., 2013, 555, A39). We find that significant carbonaceous dust re-processing and/or mantle accretion can occur in the outer regions of molecular clouds and that this dust will have significantly different optical properties from the dust in the adjacent diffuse ISM. We conclude that the (re-)processing and cycling of carbon into and out of dust is perhaps the key to advancing our understanding of dust evolution in the ISM.Comment: 14 pages, 6 figure

    Exploiting the Signal-Leak Bias in Diffusion Models

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    There is a bias in the inference pipeline of most diffusion models. This bias arises from a signal leak whose distribution deviates from the noise distribution, creating a discrepancy between training and inference processes. We demonstrate that this signal-leak bias is particularly significant when models are tuned to a specific style, causing sub-optimal style matching. Recent research tries to avoid the signal leakage during training. We instead show how we can exploit this signal-leak bias in existing diffusion models to allow more control over the generated images. This enables us to generate images with more varied brightness, and images that better match a desired style or color. By modeling the distribution of the signal leak in the spatial frequency and pixel domains, and including a signal leak in the initial latent, we generate images that better match expected results without any additional training.Comment: corrected the author names in reference [24

    Planeamiento estratégico para la empresa Comercial Molinera San Luis S.A.C.

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    El arroz en cáscara sigue siendo el principal producto dentro del portafolio de productos agrícolas del Perú; a su vez el consumo per cápita de arroz pilado es uno de los mayores de América Latina. Lambayeque representa una de las regiones de mayor producción de arroz en cáscara e implementación de molinos y su ubicación geográfica le permite tener una situación estratégica favorable para la captación de arroz en cáscara de regiones anexas de gran producción, como San Martín y Amazonas, cuyos productores muchas veces optan por llevar su arroz en cáscara a molinos de Lambayeque, por la tecnología de sus procesos y mejor mercado para la comercialización. El presente plan estratégico tiene como objetivo situar al año 2030 a la empresa Comercial Molinera San Luis S.A.C. (COMOLSA) como el primer productor y exportador de arroz pilado del Perú; para ello se han establecido cinco objetivos de largo plazo referidos a intereses de incrementar participación en el mercado de molienda de arroz en cáscara, mejoramiento de la calidad de los procesos y productos, así como, incursionar en mercados internacionales para exportación de arroz pilado. Se han seleccionado nueve estrategias para el logro de los objetivos y por ende de la visión, destacando la implementación de un plan de habilitación para productores, el mejoramiento del valor nutritivo del arroz, el ingreso al mercado de producción de arroz pilado en la región San Martin, la exportación de arroz pilado a Colombia y la implementación de un modelo de calidad con fines de obtener certificaciones internacionales.Paddy rice is still the main product in the portfolio of agricultural products in Peru; At the same time, the consumption of rice per capita is one of the largest in Latin America. Lambayeque represents one of the regions with the highest production of paddy rice and mill implementation and its geographical location allows it to have a favorable strategic situation for the capture of paddy rice from annexed regions of large production, such as San Martín and Amazonas, whose producers choose to take their rice in husks to Lambayeque mills, due to the technology of their processes and a better market for marketing. The objective of this strategic plan is to place the company Comercial Molinera San Luis S.A.C. (COMOLSA) as Peru's first producer and exporter of rice by 2030; to this end, five long-term objectives have been established regarding interests of increasing participation in the market for crushing rice in husks, improvement of the quality of processes and export incursion of piled rice. Nine strategies have been selected to achieve the objectives and therefore the vision, highlighting the implementation of a qualification plan for producers, the improvement of the nutritional value of rice, the entry into the market for the production of rice in the San Martin region, the export of rice to Colombia and the implementation of a quality model with purposes of obtaining international certifications.Tesi

    BDNF Val66Met polymorphism and protein levels in Amniotic Fluid

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    Brain-Derived Neurotrophic Factor (BDNF) is a neurotrophin which plays survival- and growth-promoting activity in neuronal cells and it is involved in cellular plasticity mechanisms as it controls activity dependent synaptic transmission. A functional polymorphism (Val66Met) in the pro-region of BDNF, which affects the intracellular trafficking of proBDNF has been associated with memory and cognitive deficits as well as to an increased susceptibility for several psychiatric disorders especially those with a neurodevelopmental origin. To date, no study has evaluated the influence of the Val66Met polymorphism on BDNF levels in a peripheral system that may reflect fetal neurodevelopment. Therefore we investigated in amniotic fluids (AF) obtained from 139 healthy women during 15-17 week of pregnancy, BDNF protein levels in correlation with the Val66Met polymorphism

    Plan de gestión de responsabilidad social a través de la producción y venta de mermelada en el sector VII de El Milagro, Trujillo – Perú

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    Se realizó un trabajo de investigación con el propósito de mejorar la condición de vida de las madres de familia a través de su participación en la elaboración de mermeladas para la venta directa en el Sector VII del Milagro, Trujillo – Perú, con el supuesto que dicha actividad crece junto a una adecuada gestión de responsabilidad social. El estudio tuvo carácter proyectivo y aplicado, donde se dio solución a una necesidad de tipo práctica a las madres de familia, para ello como metodología se dispuso del diagnóstico, diseño y ejecución del plan de acciones para la elaboración de mermelada, utilizándose herramientas como encuestas, registro y/o base de datos, entrevistas y observación. Se identificó las mayores necesidades en base al Censo Poblacional UPN realizado el presente año. Se priorizó y determinó el problema socio-ambiental a resolver en la comunidad. Se analizó el problema por medio de la matriz de interrelación FDOR, y a partir de éste se formuló los objetivos del proyecto. Posteriormente, se elaboró y ejecutó el plan de acciones en base a la programación de actividades y sus respectivos indicadores. Se determinó que con la ejecución del plan de acciones para la elaboración de mermelada en base a la producción de un (1) frasco de mermelada, se genera una ganancia del 81.81% equivalente a 1.80 nuevos soles por frasco producido

    Plan de gestión de responsabilidad social a través de la producción y venta de mermelada en el sector VII de El Milagro, Trujillo – Perú [Management plan for social responsibility through and sale of marmalade production in the sector VII of the El Milagro, Trujillo – Peru]

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    RESUMEN Se realizó un trabajo de investigación con el propósito de mejorar la condición de vida de las madres de familia a través de su participación en la elaboración de mermeladas para la venta directa en el Sector VII del Milagro, Trujillo – Perú, con el supuesto que dicha actividad crece junto a una adecuada gestión de responsabilidad social. El estudio tuvo carácter proyectivo y aplicado, donde se dio solución a una necesidad de tipo práctica a las madres de familia, para ello como metodología se dispuso del diagnóstico, diseño y ejecución del plan de acciones para la elaboración de mermelada, utilizándose herramientas como encuestas, registro y/o base de datos, entrevistas y observación. Se identificó las mayores necesidades en base al Censo Poblacional UPN realizado el presente año. Se priorizó y determinó el problema socio-ambiental a resolver en la comunidad. Se analizó el problema por medio de la matriz de interrelación FDOR, y a partir de éste se formuló los objetivos del proyecto. Posteriormente, se elaboró y ejecutó el plan de acciones en base a la programación de actividades y sus respectivos indicadores. Se determinó que con la ejecución del plan de acciones para la elaboración de mermelada en base a la producción de un (1) frasco de mermelada, se genera una ganancia del 81.81% equivalente a 1.80 nuevos soles por frasco producido.ABSTRACT A research was conducted with the aim of improving the living conditions of mothers through its participation in the preparation of jams for direct sale in Sector VII of the Miracle, Trujillo - Peru, with the assumption that the activity grows with proper management of social responsibility. The study had projective and applied nature, which solution is given to a need for practical kind to mothers, to it as methodology was available diagnosis, design and implementation of the action plan for making jam, using tools such as surveys, registration and / or database, interviews and observation. The greatest needs are identified based on the Population Census UPN made this year. Priority was given and determined the socio-environmental problem to be solved in the community. The problem was analyzed through FDOR matrix interaction, and from this the objectives of the project was formulated. Later, he developed and implemented the plan of action based on the program of activities and their respective indicators. It was determined that with the implementation of the action plan for making jam based on the production of one (1) jar of jam, a gain of 81.81%, equivalent to 1.80 soles per bottle produced is generated

    Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

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    Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR < 60 mL/min/1.73 m2) or eGFR reduction > 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR < 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR > 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening

    Pivotal role of GABAergic neurons of the basolateral amygdala in relaying hippocampal and serotonergic information

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    The amygdala is a brain structure located in the temporal lobe that coordinates a wide range of emotional behaviours, in particular fear responses. Neuroimaging studies in humans have shown that in patients with post-traumatic stress disorder (PTSD) and phobias the amygdala is hyper-responsive to emotional stimuli. Thus, deciphering the neuronal mechanisms through which the amygdala orchestrates fear responses may improve treatments for pathological fear. In the last decades it has become evident from rodent experiments that neuronal circuits of the basolateral nucleus of the amygdala (BLA) control the acquisition and retrieval of fear memories. This is achieved through precise control of glutamatergic principal neuron (PN) activity by the release of γ-aminobutyric acid (GABA) from distinct populations of inhibitory neurons. Notably, the firing of BLA neurons is moulded by a vast array of extrinsic structures, namely sensory areas of the cortex, regions involved in memory processing and subcortical neuromodulatory afferents. However, the cellular mechanisms enabling the modulation of BLA circuits by afferent regions are still poorly understood. The modulation of BLA circuits by the hippocampus and by the neuromodulator serotonin (5-HT) is of particular interest because these pathways may be of clinical importance. Nonetheless, these inputs have received little attention using circuit-based approaches. To fill this gap, I used a combination of ex vivo recordings from brain slices, in vivo recordings from anaesthetised mice, optogenetics, pharmacology, behavioural tests and immunohistochemistry. These experiments reveal that GABAergic neurons of the BLA are key nodes through which hippocampus and 5-HT modulate the excitability of PNs, the main output of the BLA. Specifically, optogenetic activation of ventral hippocampus pyramidal cells axons recruits BLA GABAergic interneurons that provide feedforward inhibition onto PNs. However, activation of hippocampal axons at theta frequency triggers a GABAB dependent depression of feedforward inhibition, creating time windows in which the induction of synaptic plasticity of parallel excitatory pathways is facilitated. Furthermore, GABAergic interneurons expressing parvalbumin (PV) are a prominent target of the 5-HT action in the BLA. 5-HT depolarizes these cells via 5-HT2A receptors, enhancing PN inhibition. Remarkably, in mice overexpressing the 5-HT transporter (5-HTT), an animal model of a genetic 5-HTT variation occurring in humans, PV+ interneurons display reduced depolarization by 5-HT and diminished recruitment by fear memory recall. Finally, I report a novel GABAergic neuron type of the BLA that expresses high levels of neuronal nitric oxide synthase (nNOS). These cells are instead hyperpolarized by 5-HT via 5-HT1A receptors, representing the first example of a BLA inhibitory neuron inhibited by this neuromodulator. Assessment of their c-Fos immunoreactivity showed that nNOS+ cells are active during sleep but not during wakefulness. Since 5-HT is highly released during the latter but not the former vigilance state, its hyperpolarizing action on nNOS+ cells provides a putative mechanism through which these cells are activated in a brain state-dependent fashion. My results demonstrate that hippocampus and 5-HT influence BLA microcircuits via prominent action on GABAergic cells. Notably, 5-HT appears to exert GABAergic cell type specific actions, suggesting that studying the impact of extrinsic pathways on defined amygdala neuron types can be decisive to comprehend the neural circuits controlling emotional learning.</p

    Pivotal role of GABAergic neurons of the basolateral amygdala in relaying hippocampal and serotonergic information

    No full text
    The amygdala is a brain structure located in the temporal lobe that coordinates a wide range of emotional behaviours, in particular fear responses. Neuroimaging studies in humans have shown that in patients with post-traumatic stress disorder (PTSD) and phobias the amygdala is hyper-responsive to emotional stimuli. Thus, deciphering the neuronal mechanisms through which the amygdala orchestrates fear responses may improve treatments for pathological fear. In the last decades it has become evident from rodent experiments that neuronal circuits of the basolateral nucleus of the amygdala (BLA) control the acquisition and retrieval of fear memories. This is achieved through precise control of glutamatergic principal neuron (PN) activity by the release of &gamma;-aminobutyric acid (GABA) from distinct populations of inhibitory neurons. Notably, the firing of BLA neurons is moulded by a vast array of extrinsic structures, namely sensory areas of the cortex, regions involved in memory processing and subcortical neuromodulatory afferents. However, the cellular mechanisms enabling the modulation of BLA circuits by afferent regions are still poorly understood. The modulation of BLA circuits by the hippocampus and by the neuromodulator serotonin (5-HT) is of particular interest because these pathways may be of clinical importance. Nonetheless, these inputs have received little attention using circuit-based approaches. To fill this gap, I used a combination of ex vivo recordings from brain slices, in vivo recordings from anaesthetised mice, optogenetics, pharmacology, behavioural tests and immunohistochemistry. These experiments reveal that GABAergic neurons of the BLA are key nodes through which hippocampus and 5-HT modulate the excitability of PNs, the main output of the BLA. Specifically, optogenetic activation of ventral hippocampus pyramidal cells axons recruits BLA GABAergic interneurons that provide feedforward inhibition onto PNs. However, activation of hippocampal axons at theta frequency triggers a GABAB dependent depression of feedforward inhibition, creating time windows in which the induction of synaptic plasticity of parallel excitatory pathways is facilitated. Furthermore, GABAergic interneurons expressing parvalbumin (PV) are a prominent target of the 5-HT action in the BLA. 5-HT depolarizes these cells via 5-HT2A receptors, enhancing PN inhibition. Remarkably, in mice overexpressing the 5-HT transporter (5-HTT), an animal model of a genetic 5-HTT variation occurring in humans, PV+ interneurons display reduced depolarization by 5-HT and diminished recruitment by fear memory recall. Finally, I report a novel GABAergic neuron type of the BLA that expresses high levels of neuronal nitric oxide synthase (nNOS). These cells are instead hyperpolarized by 5-HT via 5-HT1A receptors, representing the first example of a BLA inhibitory neuron inhibited by this neuromodulator. Assessment of their c-Fos immunoreactivity showed that nNOS+ cells are active during sleep but not during wakefulness. Since 5-HT is highly released during the latter but not the former vigilance state, its hyperpolarizing action on nNOS+ cells provides a putative mechanism through which these cells are activated in a brain state-dependent fashion. My results demonstrate that hippocampus and 5-HT influence BLA microcircuits via prominent action on GABAergic cells. Notably, 5-HT appears to exert GABAergic cell type specific actions, suggesting that studying the impact of extrinsic pathways on defined amygdala neuron types can be decisive to comprehend the neural circuits controlling emotional learning.</p
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