Translators to Higher Order Mean Curvature Flows in Rn×R\mathbb R^n\times\mathbb R and Hn×R\mathbb H^n\times\mathbb R

We consider translators to the extrinsic flows defined by the higher order mean curvatures $H_r$ ($r$-MCF, for short) in $\mathbb R^n\times\mathbb R$ and $\mathbb H^n\times\mathbb R,$ where $n\ge 2$ and $r\in\{1,\dots,n-1\}.$ We show that there exist rotational bowl-type and translating catenoid-type translators to $r$-MCF in both $\mathbb R^n\times\mathbb R$ and $\mathbb H^n\times\mathbb R,$ and also that there exist parabolic and hyperbolic translating catenoid-type translators to $r$-MCF in $\mathbb H^n\times\mathbb R.$ We also establish the uniqueness (together with the Euclidean and hyperbolic grim reapers, and the vertical totally geodesic hyperplanes) of these translators among those which are invariant by either rotations or translations (Euclidean, parabolic or hyperbolic). Our main results extend to the context of $r$-MCF in $\mathbb R^n\times\mathbb R$ and $\mathbb H^n\times\mathbb R$ the existence and uniqueness theorems by Altschuler--Wu (of the bowl soliton) and Clutterbuck--Schn\"urer--Schulze (of the translating catenoids) in Euclidean space

Occurrence of Mycotoxin in Farro Samples from Southern Italy

The occurrence of nine mycotoxins and of contamination by pre- and postharvest fungal pathogens of cereals was investigated in samples of stored Triticum monococcum L., Triticum dicoccon Schrank (emmer), and Triticum spelta L. (spelt). In Italy, all three species are collectively referred to as farro. The samples examined were harvested in summer 2000 from eight different sites in southern Italy. Conventional fluorimetric and diode array-based high-performance liquid chromatography (HPLC) analyses and HPLC-mass spectrometry analyses were used to identify fumonisin B1 in five samples (up to 70.00 microg/ kg), ochratoxin A in seven samples (up to 4.07 microg/kg), and beauvericin in three samples (up to 4.44 mg/kg). Enniatin B was detected in one sample (30.00 microg/kg), but no zearalenone or fusaproliferin was found. Deoxynivalenol and aflatoxins were not evaluated. The potentially mycotoxigenic fungal species detected were Alternaria alternata, Fusarium proliferatum, Fusarium tricinctum, Penicillium verrucosum, and Penicillium chrysogenum. This is the first report of the natural occurrence of mycotoxins in farro samples

Engineering properties of geopolymer concrete: a review

Geopolymer concrete (GPC) could be a solution that uses a cementless binder and recycled materials for producing concrete, while reducing the carbon dioxide emission and the demand for raw materials. In addition to the environmental aspect, previous studies on GPC showed that it can achieve mechanical characteristics higher than those of ordinary Portland concrete (OPC) such as greater strength a few days after casting, and it can be suitable for structural applications. In this paper, the state-of-the-art review of GPC is presented through an extensive literature analysis to determine the most recent information regarding the engineering properties of geopolymer concrete and the critical issues that prevent its widespread use and to put forward suggestions for future research. In particular, the physical properties in both fresh and hardened states and the mechanical characteristics are investigated; the structural performance of geopolymer concrete elements is also outlined

Bell scenarios in which nonlocality and entanglement are inversely related

We show that for two-qubit chained Bell inequalities with an arbitrary number of measurement settings, nonlocality and entanglement are not only different properties but are inversely related. Specifically, we analytically prove that in absence of noise, robustness of nonlocality, defined as the maximum fraction of detection events that can be lost such that the remaining ones still do not admit a local model, and concurrence are inversely related for any chained Bell inequality with an arbitrary number of settings. The closer quantum states are to product states, the harder it is to reproduce quantum correlations with local models. We also show that, in presence of noise, nonlocality and entanglement are simultaneously maximized only when the noise level is equal to the maximum level tolerated by the inequality; in any other case, a more nonlocal state is always obtained by reducing the entanglement. In addition, we observed that robustness of nonlocality and concurrence are also inversely related for the Bell scenarios defined by the tight two-qubit three-setting $I_{3322}$ inequality, and the tight two-qutrit inequality $I_3$.Comment: 9 page

Microalgae in the Mediterranean area: A geographical survey outlining the diversity and technological potential

Microalgal diversity enables the possibility to employ them in technological applications, as widely shown by the modern literature. While there exists an extensive body of literature concerning the technological applications of microalgae, the scientific knowledge of microalgal species remains relatively limited. Therefore, there is still potential for unlocking new opportunities through the study of the microalgal biodiversity, particularly in the Mediterranean region, which is unique because of its sub regional diversity. While some studies have assessed microalgae distribution in the Mediterranean area, and others have focused on specific aspects of their technical exploitation, this review seeks to offer a comprehensive overview of isolated microalgal species and their technological applications. Microalgae from the Mediterranean area share common characteristics, such as low half-saturation constants and acclimation to high light intensity, making them ideal for specific technological applications. While the search for new microalgae for technological purposes can help in biodiversity conservation, numerous species still remain underexplored, offering potential for innovative applications. However, the key finding from the critical analysis of the literature is that the diversity of microalgae in the Mediterranean region is its true richness, allowing for their versatile applications across various processes. The work focuses on the Mediterranean area, i.e., having coastlines along the Mediterranean Sea and on aquatic microalgae, coming from water with different salinity levels. This review offers an intrinsic ecological and technological perspective and provides a fresh outlook on the microalgal sector, promoting its expansion in the Mediterranean area and the development of sustainable bio-industrie

Development of an Electrochemical Sensor for Nitrate Analysis in Municipal Wastewaters Treated by Microalgae

Microalgae are photosynthetic microorganisms which may be employed in several fields. Amongst them, an emerging but promising sector of application is their usage for the remediation of wastewaters. They result particularly effective in treating municipal wastewaters, often resulting in nitrate concentrations exceeding the requirements for discharging treated wastewater into the sea. Furthermore, another advantage of using microalgae in civil wastewater treatment is the cooperation with heterotrophic bacteria which may naturally occur in the water or be introduced through sewage sludge in wastewater treatment plants (WTPs). Microalgae, in fact, produce oxygen which may be used by these bacteria reducing the overall operational costs of the WTP. The assessment of nitrogen compound concentrations in wastewater involves various techniques, with ionic chromatography (IC) and spectrometric methods being commonly used in laboratory settings. However, these methods have drawbacks such as the need for skilled personnel, time-consuming processes, and impracticality for in situ and real-time analysis. To address these issues, electrochemical sensors present a viable alternative. These sensors require portable instruments with low power requirements and can be miniaturized using nanotechnology. Electrochemical sensors operate by reducing/oxidizing the target analyte on the working electrode surface. The choice of electrode material is crucial for sensor sensitivity, and copper is found to exhibit excellent electrocatalytic properties for reducing nitrate ions in acidic media. In this study, a cost-effective electrochemical sensor made of copper was developed for quantifying nitrate in wastewater. The entire electrochemical cell was constructed from a common substrate used in Printed Circuit Boards (PCB). The whole fabrication procedure was optimized in order to obtain a reproducible fabrication procedure. The reference and counter electrodes were modified with graphite and Ag/AgCl paste, respectively. The results demonstrated that the sensor can effectively quantify nitrate ions in wastewater. Moreover, it can be employed during microalgal treatment to assess the in vivo reduction of nitrate, offering a practical and efficient solution for real-time monitoring of nitrogen compounds in wastewater treatment processes

Experimental and Computational Study of Supercritical Fluid Extraction (SFE) of Omega-3 Components from Fish Oil in Structured Packing

The benefits of polyunsaturated fatty acids and their implications for human health have gained scientific attention to their extraction from biological sources, not being produced by the human body. Most known industrial productions of omega-3 fatty acids often work under operating conditions that may degrade these components and they often use toxic or flammable solvents that can adversely affect human health. In this sense, innovative and interesting prospects are provided by Supercritical Fluid Extraction (SFE). In this work, two parallel studies were carried out: an experimental activity in a laboratory apparatus using supercritical carbon dioxide (scCO2) and preliminary computational fluid dynamics (CFD) simulations, limited to the hydrodynamic aspects of the process. In the experimental apparatus a Sulzer® EX structured packing, made up of corrugated metal gauze sheets, was used as the column filler. The study made it possible to identify the optimal operating conditions leading to an enrichment of the starting mixture in Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA), target products. CFD simulations were based on the Volume of Fluid (VOF) approach, suitable to the present complex multiphase system with two phases in close contact (transesterified fish oil and scCO2). The meatus created by the corrugations of the metal gauze was chosen as the calculation domain representative of the system. The computations were performed by the commercial software Ansys Fluent®, which allowed the prediction of the hydrodynamic evolution of the system through transient simulations. CFD predictions were in qualitative agreement with the experimental result

Kinetic of the Sewage Treatment: The Consumption of Organic Carbon of The Microalga Chlorella sp

As well known, microalgae are eukaryotic or procaryotic microorganisms able to photosynthesize, namely transforming inorganic substrates and sun light into organic compounds and chemical energy. They result very promising in treating civil wastewaters thanks to their ability to employ nitrates and phosphates as nutrients (Lima et al., 2019). Autotrophic microalgae are, anyway, not useful in decreasing the organic carbon content of wastewaters, and for this reason, they cooperate with heterotrophic bacteria. The usefulness of microalgaebacteria consortia in treating wastewaters and the ratio of their inoculum was investigated in a previous work (Lima, 2022a). Contrarily to autotrophic microalgae, mixotrophic microalgae are able to decrease the organic content of the matrix in which they are grown. In this work, we preliminarily investigated the capability of the autochthonous microalga Chlorella sp. CW2 to grow in mixotrophy and decrease the organic content of the artificial wastewater in which they are grown. Several batch cultivations were performed with glucose in different concentrations. Kinetic parameters were obtained and employed to determine the dilution rate (D) ideal for the abatement of glucose from the artificial wastewater

Integration of biocontrol agents and food-grade additives for enhancing protection of stored apples from Penicillium expansum.

Forty-nine compounds currently used as additives in foods were tested in combination with three biocontrol agents, the yeasts Rhodotorula glutinis, Cryptococcus laurentii, and the yeastlike fungus Aureobasidium pullulans, to increase their antagonistic activity against Penicillium expansum, the causal agent of blue mold on apples. Twelve additives dramatically improved the antagonistic activity of one or more of the tested biocontrol agents. In a two-way factorial experiment with these selected additives the percentage of P. expansum rots on apples was significantly influenced by the antagonist and the additive as well as by their interaction. The combination of the biocontrol agents and some additives resulted in a significantly higher activity with respect to the single treatments applied separately, producing additive or synergistic effects. Some of the selected additives combined with a low yeast concentration (106 cells per ml) had comparable or higher efficacy than the biocontrol agents applied alone at a 100-fold higher concentration (10(8) cells per ml). Some organic and inorganic calcium salts, natural gums, and some antioxidants displayed the best results. In general, the effect of each additive was specific to the biocontrol isolate used in the experiments. Possible mechanisms involved in the activity of these beneficial additives and their potential application in effective formulations of postharvest biofungicides are discussed

The value of magnetic resonance imaging for the detection of focal liver lesions using different T-2 weighted techniques: is there a consensus?

Since the early 1980's several magnetic resonance imaging pulse sequences have been developed in order to determine the optimum imaging technique for the detection and characterization of hepatic lesions. T2-weighted images play an important role in the evaluation of the liver and present equal or greater sensitivity than enhanced computed tomography for the detection of liver lesions. New techniques for obtaining T-2 weighted images have been developed in the attempt to optimize the method. These techniques have improved the image quality by shortening examination time, reducing motion artifacts, and improving contrast-to-noise ratio. The effectiveness of the different techniques (fat suppression, breath-hold, respiratory-triggered and phased-array coils) has been tested in many comparative studies, although the results are controversial. In this article we review the literature and discuss the several T2-weighted image techniques, particularly with regard to sensitivity to detect focal liver lesions.Desde o início da década de 80 a ressonância magnética vem sendo utilizada para o estudo do abdome e principalmente na detecção de nódulos hepáticos. As imagens ponderadas em T2 são as que trouxeram maior benefício quando comparadas à tomografia computadorizada com contraste. Inúmeras técnicas e seqüências de ressonância magnética ponderadas em T2 surgiram desde então, na tentativa de aumentar a eficácia diagnóstica, com menores tempos de exame. Neste sentido, foram publicados inúmeros trabalhos demonstrando a utilidade de seqüências rápidas e ultra-rápidas, com e sem supressão de gordura, em apnéia, com sincronizador respiratório e com bobinas de sinergia, entre outros avanços tecnológicos. No entanto, não há um consenso sobre qual a técnica mais apropriada e sensível para a detecção de lesões hepáticas focais. Neste artigo fazemos uma revisão bibliográfica e análise crítica das diversas técnicas de imagens ponderadas em T2, no que diz respeito às suas sensibilidades na detecção de nódulos hepáticos.UNIFESP-EPM Departamento de Diagnóstico por ImagemUNIFESP, EPM, Depto. de Diagnóstico por ImagemSciEL