Fabrication of hot-wire probes and electronics for constant temperature anemometers

The purpose of this paper is to discuss the construction of constant temperature hot wire anemometers. Different options are analyzed for the fabrication of sensors and electronics. A practical and simple method is developed to manufacture the probe and associated electronics. The fabricated sensor has a diameter of 2 µm and approximately 500 µm in length. The associated electronics are designed to keep the sensor working at a constant temperature and allow the indirect measurement of speed. The design is simple, inexpensive and highly flexible regarding its use and modifications. The dynamic tests performed and the comparison with a commercial model shows a satisfactory performance. The unit built also includes an option for testing with a square wave, which is generated internally, and a comparator mode to measure the resistance of the sensor.Fil: Osorio, Orlando Darío. Comisión Nacional de Energía Atómica. Gerencia del Area de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Silin, Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Area de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Converti, J.. Comisión Nacional de Energía Atómica. Gerencia del Area de Energía Nuclear. Instituto Balseiro; Argentin

A circular economy approach for olive oil industry: From olive pomace to microalgal biomass

In this work olive pomace was used to recover high added value compounds and produce biogas by anaerobic digestion. Moreover, in order to satisfy the circular economy concept, the digestate from the latter process was used as medium for the microalga Chlorella vulgaris growth

Influence of ammonium sulphate feeding time on fed-batch Arthrospira (Spirulina) platensis cultivation and biomass composition with and without pH control.

Previous work demonstrated that a mixture of NH(4)Cl and KNO(3) as nitrogen source was beneficial to fed-batch Arthrospira (Spirulina) platensis cultivation, in terms of either lower costs or higher cell concentration. On the basis of those results, this study focused on the use of a cheaper nitrogen source mixture, namely (NH(4))(2)SO(4) plus NaNO(3), varying the ammonium feeding time (T=7-15 days), either controlling the pH by CO(2) addition or not. A. platensis was cultivated in mini-tanks at 30°C, 156 μmol photons m(-2) s(-1), and starting cell concentration of 400 mg L(-1), on a modified Schlösser medium. T=13 days under pH control were selected as optimum conditions, ensuring the best results in terms of biomass production (maximum cell concentration of 2911 mg L(-1), cell productivity of 179 mg L(-1)d(-1) and specific growth rate of 0.77 d(-1)) and satisfactory protein and lipid contents (around 30% each)

Tools for Optimization of Biomass-to-Energy Conversion Processes

Biomasses are renewable sources used in energy conversion processes to obtain diverse products through different technologies. The production chain, which involves delivery, logistics, pre-treatment, storage and conversion as general components, can be costly and uncertain due to inherent variability. Optimization methods are widely applied for modeling the biomass supply chain (BSC) for energy processes. In this qualitative review, the main aspects and global trends of using geographic information systems (GISs), linear programming (LP) and neural networks to optimize the BSC are presented. Modeling objectives and factors considered in studies published in the last 25 years are reviewed, enabling a broad overview of the BSC to support decisions at strategic, tactical and operational levels. Combined techniques have been used for different purposes: GISs for spatial analyses of biomass; neural networks for higher heating value (HHV) correlations; and linear programming and its variations for achieving objectives in general, such as costs and emissions reduction. This study reinforces the progress evidenced in the literature and envisions the increasing inclusion of socio-environmental criteria as a challenge in future modeling efforts

New trends in biotechnological processes to increase the environmental protection

A sustainable development can be achieved by deepening into more effective and eco-friendly products and technologies. From this point of view, the development of biotechnological processes to increase the environmental protection could be included in the best available techniques reference documents, the so-called BREFs, that cover, as far as practicable, the industrial activities to achieve an integrated pollution prevention and control. Members of the European Union are required to take these documents into account when determining the best available techniques, generally or in specific cases under the European Commission Directives. In order to include biotechnological processes into the BREFs, for example, for obtaining food and pharmaceutical additives, these products have to be cost competitive with those synthesized by chemical ways. Biotechnological processes are advantageous compared to the chemical ones since various metabolites can be obtained simultaneously in the same process, and these metabolites are more eco-friendly than their chemical counterparts. Additionally, this feature also matches the increasing demand of consumers for natural products, which has intensified the biotechnological production of natural additives. This special issue reports advances in the use of biotechnological processes for the treatment of contaminated soil or water as well as the revalorization of agroindustrial residues through the production of valuable metabolites such as biosurfactants or antioxidants, with applications in biomedicine, food industry, pharmaceutical industry, or environmental bioremediation

Bacteriocin production by Lactobacillus plantarum ST16Pa in supplemented whey powder formulations

Whey, the main by-product of the dairy industry, is frequently disposed of in the environment without any treatment due to the high cost of this process. Alternatively, whey can be used as a medium to culture lactic acid bacteria and produce value-added products such as bacteriocins. In this work, we attempted to improve bacteriocin production by Lactobacillus plantarum ST16Pa in a whey powder formulation supplemented with additional sources of carbon, nitrogen, and vitamin B12 at different levels and varying the agitation intensity according to a Plackett-Burman experimental design. Only the addition of tryptone positively influenced the production of this bacteriocin. The results allowed us to identify a supplemented whey formulation, comprising 150 g/L of whey total solids plus 10 g/L of tryptone and soybean extract, whose fermentation by Lb. plantarum ST16Pa in shake flasks under agitation at 150 rpm led to a cell-free supernatant with an antimicrobial activity against Listeria innocua 6a CLIST 2865 (inhibition zone of 13.23 mm) close to that previously obtained in de Man, Rogosa and Sharpe medium by other authors. These results are significant considering that the same strain cultured in cheese whey did not previously display any antimicrobial activity

Effects of light intensity and dilution rate on the semicontinuous cultivation of Arthrospira (Spirulina) platensis. A kinetic Monod-type approach.

Abstract Semicontinuous cultures were carried out at different dilution rates (D) and light intensities (I) to determine the maximum productivity of Arthrospira platensis cultivated in helicoidal photobioreactor up to the achievement of pseudo-steady-state conditions. At I = 108 μmol photons m−2 s−1, the semicontinuous regime ensured the highest values of maximum cell concentration (Xm = 5772 ± 113 mg L−1) and productivity (PXS = 1319 ± 25 mg L−1 d−1) at the lowest (D = 0.1 day−1) and the highest (D = 0.3 day−1) dilution rates, respectively. A kinetic model derived from that of Monod was proposed to determine the relationship between the product of light intensity to dilution rate (ID) and the cell productivity, which were shown to exert a combined influence on this parameter. This result put into evidence that pseudo-steady-state conditions could be modified according to circumstances, conveniently varying one or other of the two independent variables

Gobierno digital y contrataciones del Estado en una institución pública del distrito de Nuevo Chimbote, 2023

El objetivo que se propone en la investigación es: Determinar la relación entre el Gobierno digital y contrataciones del Estado en una institución pública del distrito de Nuevo Chimbote 2023, la Metodología seleccionada se basó en el tipo básica, el diseño fue el no experimental, bajo un enfoque cuantitativo, nivel correlacional y alcance transversa, la muestra considerada fue de 60 servidores públicos nombrados, además la técnica que se utilizo fue la encuesta y como instrumento se reflejó el cuestionario, pasando por el proceso de validez y de confiabilidad, logrando concluir: Se comprobó relación significativa (r=0.864; sig. 0.000<0.05) entre el Gobierno digital y contrataciones del Estado en una institución pública del distrito de Nuevo Chimbote 2023, mencionando que ambos elementos analizados se encuentran asociados y si una mejora el otro también presentará resultados positivos y si uno presenta deficiencias, el otro también se presentará de la misma manera. Así mismo se aceptó la hipótesis propuesta

Temporomandibular disorders and fibromyalgia: A narrative review

Temporomandibular disorder (TMD) and fibromyalgia (FM) have some clinical characteristics in common, for instance the chronic evolution, the pathophysiology incompletely understood and a multifactorial genesis. The incidence and the relationship between TMD and FM patients are the aims of this review. A MEDLINE and PubMed search were performed for the key words “temporomandibular disorder” AND “fibromyalgia” from 2000 to present. A total of 19 papers were included in our review, accounting for 5449 patients. Ten studies, reporting a total of 4945 patients with TMD, showed that only 16.5% of these patients had diagnosis of FM, whereas 12 studies, reporting a total of 504 patients with FM, demonstrated that 77.0% of these patients had diagnosis of TMD. A comorbid relationship exists between TMD and FM. The complexity of both diseases shows the importance of a multimodal and interdisciplinary

The effect of menopause hypoestrogenism on osteogenic differentiation of periodontal ligament cells (PDLC) and stem cells (PDLCs): A systematic review

(1) Background: Menopause is a physiological condition typified by drastic hormonal changes, and the effects of this transition have long-term significant clinical implications on the general health, including symptoms or physical changes. In menopausal women, the periodontium can be affected directly or through neural mechanism by oestrogen (E2) deficiency. The majority of the biological effects of E2 are modulated via both oestrogen receptor-α (ERα) and oestrogen receptor-β (ERβ). There is evidence that hypoestrogenism has a substantial impact on the aetiology, manifestation and severity of periodontitis, via the regulation of the expression of osteoproges-terin and RANKL in human periodontal ligament cells through ERβ. However, the mechanistic understanding of oestrogen in periodontal status has been partially clarified. The aim of this paper was to synopsize the recent scientific evidence concerning the link between the menopause and periodontitis, through the investigation of physio-pathological impact of the oestrogen deficiency on osteogenic differentiation of PDLSCs and PDLSC, as well as the dynamic change of ERα and ERβ. (2) Methods: Search was conducted for significant studies by exploring electronic PubMed and EMBASE databases, and it was independently performed by two researchers. All studies on the impact of oestrogen level on alveolar bone resorption were searched from 2005 to July 2020. Data selection was in concordance with PRISMA guidelines. (3) Results: Eight studies met the criteria and were included in this systematic review. All studies reported that oestrogen deficiency impairs the osteogenic and osteoblastic differentiation of PDL cells and oestrogen affects the bone formation capacity of cells. Seven studies were conducted on animal samples, divided into two groups: the OVX animals and animals who received the sham operation. (4) Conclusions: There is a multitude of data available showing the influence of menopause on periodontal status. However, the evidence of this line to investigation needs more research and could help explain the physiological linkage between menopause state and periodontal disease