736 research outputs found
Abundancia, Distribución y Descripción de la Pesquería del Bivalvo Atrina seminuda en el Nororiente de Venezuela
Implementation of a cogeneration plant for a food processing facility. A case study
The present work presents an investigation regarding the feasibility analysis of a cogeneration plant for a food processing facility with the aim to decrease the cost of energy supply. The monthly electricity and heat consumption profiles are analyzed, in order to understand the consumption profiles, as well as the costs of the current furniture of electricity and gas. Then, a detailed thermodynamic model of the cogeneration cycle is implemented and the investment costs are linked to the thermodynamic variables by means of cost functions. The optimal electricity power of the co-generator is determined with reference to various investment indexes. The analysis highlights that the optimal dimension varies according to the chosen indicator, therefore it is not possible to establish it univocally, but it depends on the financial/economic strategy of the company through the considered investment index
Моделирование энергопотребления зданий: оценка статической и динамической моделей
The aim of the present paper is to show recent results obtained in modeling the building system, presenting a review on the common numerical models used to estimate the energy consumptions. In particular, both steady-state and dynamic models are investigated by analyzing their main assumptions, limitations and fields of usage. As a matter of fact, the most common models are based on steady state approaches, but new technologies and the need to implement innovative regulation criteria for heating and cooling systems by performing detailed coupled studies on the building and heating/cooling systems, push towards the use of dynamic tools with low computational costs. Therefore, the use of dynamic models is often suggested, especially when different building configurations are investigated (as e. g. in the design stage or for a renovation perspective). Starting from this point, sensitive analyses on the installation of a proper insulation in the building envelope is then presented.Цель данной работы — показать последние результаты, полученные при моделировании системы здания, с описанием общих численных моделей, используемых для оценки энергопотребления. В частности на статических и динамических моделях исследованы основные допущения, ограничения и область использования путем их анализа. Собственно говоря, наиболее распространенные модели основаны на установившихся подходах, но новые технологии и необходимость внедрения для систем отопления и холодоснабжения инновационных критериев регулирования с использованием подробного анализа здания и систем отопления/охлаждения, подталкивают к использованию динамических инструментов с низкими вычислительными затратами. Таким образом, часто целесообразно использование динамических моделей, особенно когда существуют разные конфигурации здания (как, например, в стадии проектирования или для перспективной реконструкции). В статье представлен анализ установки правильного утеплителя в ограждающих конструкциях
Expression of μ-protocadherin is negatively regulated by the activation of the β-catenin signaling pathway in normal and cancer colorectal enterocytes.
Mu-protocadherin (MUCDHL) is an adhesion molecule predominantly expressed by colorectal epithelial cells which is markedly downregulated upon malignant transformation. Notably, treatment of colorectal cancer (CRC) cells with mesalazine lead to increased expression of MUCDHL, and is associated with sequestration of β-catenin on the plasma membrane and inhibition of its transcriptional activity. To better characterize the causal relationship between β-catenin and MUCDHL expression, we performed various experiments in which CRC cell lines and normal colonic organoids were subjected to culture conditions inhibiting (FH535 treatment, transcription factor 7-like 2 siRNA inactivation, Wnt withdrawal) or stimulating (LiCl treatment) β-catenin activity. We show here that expression of MUCDHL is negatively regulated by functional activation of the β-catenin signaling pathway. This finding was observed in cell culture systems representing conditions of physiological stimulation and upon constitutive activation of β-catenin in CRC. The ability of MUCDHL to sequester and inhibit β-catenin appears to provide a positive feedback enforcing the effect of β-catenin inhibitors rather than serving as the primary mechanism responsible for β-catenin inhibition. Moreover, MUCDHL might have a role as biomarker in the development of CRC chemoprevention drugs endowed with β-catenin inhibitory activity
Expression of μ-protocadherin is negatively regulated by the activation of the β-catenin signaling pathway in normal and cancer colorectal enterocytes
Mu-protocadherin (MUCDHL) is an adhesion molecule predominantly expressed by colorectal epithelial cells which is markedly downregulated upon malignant transformation. Notably, treatment of colorectal cancer (CRC) cells with mesalazine lead to increased expression of MUCDHL, and is associated with sequestration of β-catenin on the plasma membrane and inhibition of its transcriptional activity. To better characterize the causal relationship between β-catenin and MUCDHL expression, we performed various experiments in which CRC cell lines and normal colonic organoids were subjected to culture conditions inhibiting (FH535 treatment, transcription factor 7-like 2 siRNA inactivation, Wnt withdrawal) or stimulating (LiCl treatment) β-catenin activity. We show here that expression of MUCDHL is negatively regulated by functional activation of the β-catenin signaling pathway. This finding was observed in cell culture systems representing conditions of physiological stimulation and upon constitutive activation of β-catenin in CRC. The ability of MUCDHL to sequester and inhibit β-catenin appears to provide a positive feedback enforcing the effect of β-catenin inhibitors rather than serving as the primary mechanism responsible for β-catenin inhibition. Moreover, MUCDHL might have a role as biomarker in the development of CRC chemoprevention drugs endowed with β-catenin inhibitory activity
Thermophysical Property Estimation by Transient Experiments: The Effect of a Biased Initial Temperature Distribution
The identification of thermophysical properties of materials in dynamic experiments can be conveniently performed by the inverse solution of the associated heat conduction problem (IHCP). The inverse technique demands the knowledge of the initial temperature distribution within the material. As only a limited number of temperature sensors (or no sensor at all) are arranged inside the test specimen, the knowledge of the initial temperature distribution is affected by some uncertainty. This uncertainty, together with other possible sources of bias in the experimental procedure, will propagate in the estimation process and the accuracy of the reconstructed thermophysical property values could deteriorate. In this work the effect on the estimated thermophysical properties due to errors in the initial temperature distribution is investigated along with a practical method to quantify this effect. Furthermore, a technique for compensating this kind of bias is proposed. The method consists in including the initial temperature distribution among the unknown functions to be estimated. In this way the effect of the initial bias is removed and the accuracy of the identified thermophysical property values is highly improved
Targeted cancer exome sequencing reveals recurrent mutations in myeloproliferative neoplasms
With the intent of dissecting the molecular complexity of Philadelphia-negative myeloproliferative neoplasms (MPN), we designed a target enrichment panel to explore, using next-generation sequencing (NGS), the mutational status of an extensive list of 2,000 cancer-associated genes and microRNAs. The genomic DNA of granulocytes and in-vitro-expanded CD3+ T-lymphocytes, as a germline control, was target-enriched and sequenced in a learning cohort of 20 MPN patients using Roche 454 technology. We identified 141 genuine somatic mutations, most of which were not previously described. To test the frequency of the identified variants, a larger validation cohort of 189 MPN patients was additionally screened for these mutations using Ion Torrent AmpliSeq NGS. Excluding the genes already described in MPN, for 8 genes (SCRIB, MIR662, BARD1, TCF12, FAT4, DAP3, POLG, and NRAS), we demonstrated a mutation frequency between 3 and 8%.
We also found that mutations at codon 12 of NRAS (NRASG12V and NRASG12D) were significantly associated, for primary myelofibrosis (PMF), with highest DIPSS-plus score categories. This association was then confirmed in 66 additional PMF patients composing a final dataset of 168 PMF showing an NRAS mutation frequency of 4.7%, which was associated with a worse outcome, as defined by the DIPSS plus score
Splitting the solar radiation in direct and diffuse components; Insights and constrains on the clearness-diffuse fraction representation
open3noIn many engineering applications, it is mandatory to know separately the solar radiation diffuse and direct components. Examples regard the assessment of the energy potentially exploitable by a system of solar thermal or photovoltaic panels and, in general, all the cases where it is necessary to calculate the radiative solar power collected by a surface. In fact, radiation components will differently project on the surface of interest and will weigh in a different manner, depending on the surface orientation, in the computation of the effective incident radiation. To perform this decomposition starting from data relative to a horizontal plane, two non-dimensional quantities, namely, the diffuse fraction, kd, and the clearness, kt, are usually put in mutual relation by correlating experimental data on a graphical ground rather than using physical considerations. In the present study, some insights are given on the shape of this correlation starting from geometric and physical considerations. It is shown that many results and graphs presented in literature have not physical meaning; rather they are simply artifacts due to geometrical or other constraints. These evidences open the way to a new approach to solar radiation decomposition founded on physical-based correlations.openScarpa, F.*; Marchitto, A.; Tagliafico, L.A.Scarpa, F.; Marchitto, A.; Tagliafico, L. A
Effect on the energy market of the potential switching to heat pumps for space heating
The main subject of this work is to understand what could happen in the Italian electricity market if a given share of building heating demand had switched from gas to electricity heating devices. The objective is to define the optimal share to switch in terms of minimization of environmental (CO2) emissions. The effects of such switching on the national energy system are analyzed from the financial point of view, depending also on the heating habits of final users. An hourly simulation of the electricity market has been performed by means of a bid stack model (BIDSM) developed at University of Genoa, calculating market prices, power plant generation typology, fuel consumption and global CO2 emissions. All the data are averaged on a national basis and results are reported for two different time schedule of heating requirements of the final users. In each case, the total energy consumption is fixed, and local "degree days" and location energy needs are considered. It seems that the use of heat pumps for building heating is a real option and that the user habits has a little impact on optimal share of switching from gas to heat pumps, at least concerning CO2 emission minimization
- …
