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In this work, a fully 3D-printed choke corrugated Gaussian profile horn antenna (GPHA) using high-conductive filaments and a low-cost modular 3D-printing technique is implemented. The choke corrugated GPHA operates in the Ka-band, with a central frequency of 28 GHz. Although the antenna can be printed in one piece as its dimensions are within the printing limits, four pieces compose the three sections of the final 3D-printed antenna. The numerical simulations and measurements of the antenna show a good agreement, validating the possibility of cost-effective modular fabrication of this complex type of antennas.

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Adsorption and ion exchange technologies are two of the most widely used approaches to separate pollutants from water; however, their intrinsic diffusion limitations continue to be a challenge. Pore functionalized membranes are a promising technology that can help overcome these challenges, but the extents of their competitive benefits and broad applicability have not been systematically evaluated. Herein, three types of adsorptive/ion exchange (IX) polymers containing strong/weak acid, strong base, and iron-chitosan complex groups were synthesized in the pores and partially on the surface of microfiltration (MF) membranes and tested for the removal of organic and inorganic cations and anions from water, including arsenic, per- and polyfluoroalkyl substances (PFAS), and calcium (hardness). When directly compared with beads (0.5-6 mm) and crushed resins (0.05 mm), adsorptive/IX pore-functionalized membranes demonstrated an increased relative sorption capacity, up to 2 orders of magnitude faster kinetics and the ability to regenerate up to 70-100% of their capacity while concentrating the initial solution concentration up to 12 times. The simple and versatile synthesis approach used to functionalize membranes, notably independent of the polymer type of the MF membrane, utilized pores throughout the entire cross section of the membrane to immobilize the polymers that contain the functional groups. Utilizing the pore volume of commercial membranes (6-112 mL/m2), the scientific weight capacity of the polymer (3.1-11.5 mequiv/g), and the synthesis conditions (e.g., monomer concentration), the theoretical adsorption/IX capacities per area of the membranes were calculated to be as high as 550 mequiv/m2, substantially higher than the 175 mequiv/m2 value needed to compete with commercially available IX resins. This work therefore shows that pore functionalized membranes are a promising path to tackle water contamination challenges, lowering separation diffusion limitations.

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This article presents a 3D-printed cylindrical dielectric resonator antenna operating at 5.8 GHz that achieves circular polarization by integrating a fully dielectric parasitic helix with a higher permittivity than the cylindrical resonator. The antenna polarization can be right-handed or left-handed depending on the turning sense of the helix. An extensive parametric study was done for the helix design to evaluate the effects of the dimensions and dielectric constant of the helix over the matching and axial ratio of the antenna. The manufacturing is made using low-loss dielectric filaments and a low-cost 3D printer. Simulation and measurement results show that both antennas are well-matched and operate with the corresponding circular polarization, with an axial ratio bandwidth compatible with UAV applications.

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In this work, the design of a fully 3D-printed dielectric polarizer based on anisotropic engineered material operating at 38 GHz is presented. The anisotropy conditions to obtain circular polarization are achieved by using an array of dielectric strips, manufactured using two different commercially available filaments for 3D-printing. To illuminate the polarizer, a low-profile horn linear array fed by transverse slots is designed and manufactured. The results show good agreement between simulations and measurements, with the designed polarizer covering the whole operation band of the antenna by keeping a similar gain when compared to the structure without the polarizer.

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Challenges associated with water separation technologies for per- and polyfluoroalkyl substances (PFASs) require efficient and sustainable processes supported by a proper understanding of the separation mechanisms. The solute rejections by nanofiltration (NF) at pH values near the membrane isoelectric point were compared to the size- and mass-transfer-dependent modeled rejection rates of these compounds in an ionized state. We find that the low pK a value of perfluorooctanoic acid (PFOA) relates to enhanced solute exclusions by minimizing the presence and partitioning of the protonated organic compound into the membrane domain. The effects of Donnan exclusion are moderate, and co-ion transport also contributes to the PFAS rejection rates. An additional support barrier with thermo-responsive (quantified by water permeance variation) adsorption/desorption properties allows for enhanced separations of PFAS. This was possible by successfully synthesizing an NF layer on top of a poly-N-isopropylacrylamide (PNIPAm) pore-functionalized microfiltration support structure. The support layer adsorbs organics (178 mg PFOA adsorbed/m2 membrane at an equilibrium concentration of 70 mg/L), and the simultaneous exclusion from the NF layer allows separations of PFOA and the smaller sized heptafluorobutyric acid from solutions containing 70 µg/L of these compounds at a high water flux of 100 L/m2-h at 7 bar.

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Human gait analysis is a standard method used for detecting and diagnosing diseases associated with gait disorders. Wearable technologies, due to their low costs and high portability, are increasingly being used in gait and other medical analyses. This paper evaluates the use of low-cost homemade textile pressure sensors to recognize gait phases. Ten sensors were integrated into stretch pants, achieving an inexpensive and pervasive solution. Nevertheless, such a simple fabrication process leads to significant sensitivity variability among sensors, hindering their adoption in precision-demanding medical applications. To tackle this issue, we evaluated the textile sensors for the classification of gait phases over three machine learning algorithms for time-series signals, namely, random forest (RF), time series forest (TSF), and multi-representation sequence learner (Mr-SEQL). Training and testing signals were generated from participants wearing the sensing pants in a test run under laboratory conditions and from an inertial sensor attached to the same pants for comparison purposes. Moreover, a new annotation method to facilitate the creation of such datasets using an ordinary webcam and a pose detection model is presented, which uses predefined rules for label generation. The results show that textile sensors successfully detect the gait phases with an average precision of 91.2% and 90.5% for RF and TSF, respectively, only 0.8% and 2.3% lower than the same values obtained from the IMU. This situation changes for Mr-SEQL, which achieved a precision of 79% for the textile sensors and 36.8% for the IMU. The overall results show the feasibility of using textile pressure sensors for human gait recognition.

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This article presents a fully 3D-printed dielectric planar lens operating in the entire Ka-band manufactured using additive manufacturing and a relatively low-cost 3D-printer. The lens consists of ten concentric rings implemented using low-loss ABS filaments with high permittivity values. By varying the infill percentages of them the required refractive indexes of each section are achieved. An additional 3D-printed matching layer, using the same manufacturing and design method was included in the lens, to reduce reflections. Simulation and measurement results show a very good agreement, which confirms the possibility of manufacturing a cost-effective broadband and planar lens solution operating in millimeter wave bands, where Low Earth Orbit Satellites (LEO) networks, future mobile communication systems (5G, 6G) and radar systems operate.

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Using PCR, we evaluated the presence of parvoviruses and Mycoplasma spp. in 123 American mink (Neovison vison), an introduced invasive carnivore in Chile. Our results showed all analyzed animals were negative for both pathogen groups. We cannot completely dismiss their presence, but if present, their prevalence should be lower than 2%.

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The design and understanding of rejection mechanisms for both positively and negatively charged nanofiltration (NF) membranes are needed for the development of highly selective separation of multivalent ions. In this study, positively charged nanofiltration membranes were created via an addition of commercially available polyallylamine hydrochloride (PAH) by conventional interfacial polymerization technique. Demonstration of real increase in surface zeta potential, along with other characterization methods, confirmed the addition of weak basic functional groups from PAH. Both positively and negatively charged NF membranes were tested for evaluating their potential as a technology for the recovery or separation of lanthanide cations (neodymium and lanthanum chloride as model salts) from aqueous sources. Particularly, the NF membranes with added PAH performed high and stable lanthanides retentions, with values around 99.3% in mixtures with high ionic strength (100 mM, equivalent to ~6,000 ppm), 99.3% rejection at 85% water recovery (and high Na+/La3+ selectivity, with 0% Na+ rejection starting at 65% recovery), and both constant lanthanum rejection and permeate flux at even pH 2.7. Donnan steric pore model with dielectric exclusion elucidated the transport mechanism of lanthanides and sodium, proving the potential of high selective separation at low permeate fluxes using positively charged NF membranes.

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This article presents the design, construction and analysis of a 3D-printed transformed hyperbolic flat lens working on the 30 GHz band. The transformed lens was printed using only one ABS dielectric filament of relative permittivity of 12, varying the infill percentage of each transformed lens section in order to achieve the permittivity values obtained with the transformation optics. The 3D-printed hyperbolic transformed lens exhibits good radiation performance compared to the original canonical lens.

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This article presents the design, construction and measurement of different 3D-printed Sievenpiper metasurfaces. The structures were printed using a conductive filament combined with regular polylactic acid PLA. Measurement shows a good agreement on the electromagnetic behaviour of the stop-bands generated by the fully 3D-printed metasurface and the simulated ideal cases, but with higher transmission losses due to the characteristics of the conductive filament.

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This article aims to provide a historical critique of the rise of three diagnostic categories: neurasthenia (late nineteenth century), neurosis (first half of the twentieth century) and depression (mid-twentieth century to the present). The hypothesis is that their broad dissemination can be explained through their link to the energy metaphor for the human body. From the mid-nineteenth century on, the concept of energy spread through western culture, encouraging certain fictions about what we are - the ontological dimension - and what we could be - the ethical dimension. The article shows that these pathologies have codified and made intelligible a set of life trajectories that did not obey the imperatives of those onto-ethical fictions.

El artículo tiene por objetivo realizar una historia crítica del auge de tres categorías diagnósticas: la neurastenia (fin del siglo XIX), la neurosis (primera mitad del siglo XX) y la depresión (segunda mitad del siglo XX hasta nuestros días). La hipótesis es que su amplia difusión se explicaría debido al vínculo que ellas han tenido con la metáfora energética del ser humano. Desde mediados del siglo XIX, la concepción energética se difundió por la cultura occidental, habilitando ciertas ficciones acerca de lo que somos ­ dimensión ontológica ­ y lo que podríamos llegar a ser ­ dimensión ética. El artículo muestra que estas patologías han codificado y tornado inteligible determinadas trayectorias vitales que no cumplían con los imperativos de tales ficciones onto-éticas.

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Resumen El artículo tiene por objetivo realizar una historia crítica del auge de tres categorías diagnósticas: la neurastenia (fin del siglo XIX), la neurosis (primera mitad del siglo XX) y la depresión (segunda mitad del siglo XX hasta nuestros días). La hipótesis es que su amplia difusión se explicaría debido al vínculo que ellas han tenido con la metáfora energética del ser humano. Desde mediados del siglo XIX, la concepción energética se difundió por la cultura occidental, habilitando ciertas ficciones acerca de lo que somos - dimensión ontológica - y lo que podríamos llegar a ser - dimensión ética. El artículo muestra que estas patologías han codificado y tornado inteligible determinadas trayectorias vitales que no cumplían con los imperativos de tales ficciones onto-éticas.

Abstract This article aims to provide a historical critique of the rise of three diagnostic categories: neurasthenia (late nineteenth century), neurosis (first half of the twentieth century) and depression (mid-twentieth century to the present). The hypothesis is that their broad dissemination can be explained through their link to the energy metaphor for the human body. From the mid-nineteenth century on, the concept of energy spread through western culture, encouraging certain fictions about what we are - the ontological dimension - and what we could be - the ethical dimension. The article shows that these pathologies have codified and made intelligible a set of life trajectories that did not obey the imperatives of those onto-ethical fictions.

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The American mink, Neovison vison, is an invasive species in Chile. Its impact on native fauna and public health has not been studied in depth in the country. In this study, we searched for gastrointestinal parasites, including helminths and zoonotic Cryptosporidium sp., the presence of Trichinella sp. in muscle, and the renal carriage of pathogenic Leptospira sp. in minks caught on Navarino Island, "Magallanes y la Antártica Chilena" Region, and Maullín and Ancud, "Los Lagos" Region, Chile. A total of 58, 15, and 21 minks from Navarino Island, Maullín, and Ancud, respectively, were examined for Trichinella sp. (artificial digestion of muscle). A total of 36, 11, and 17 minks from Navarino Island, Maullín, and Ancud, respectively, were examined for pathogenic Leptospira species (molecular detection of LipL32 gen fragment in renal tissue) infection. Finally, 45, 11, and 17 minks from Navarino Island, Maullín, and Ancud, respectively, were analyzed to detect gastrointestinal parasites (by optical inspection of the digestive tract for helminths, and by both Ziehl-Neelsen stain and molecular detection of small subunit-ribosomal DNA for Cryptosporidium species). Trichinella larvae were not observed. Pathogenic Leptospira sp. was detected in 22 samples: 15 from Navarino Island, 3 from Maullín, and 4 from Ancud. Two nematodes, belonging to Ascaridinae (subfamily) and Pterygodermatites (Paucipectines) sp., were found in samples of two minks from Navarino Island. Oocysts and DNA of Cryptosporidium sp. were detected in three fecal samples from Navarino Island. Further studies could determine the zoonotic potential of Cryptosporidium sp., as well as the potential impact of the zoonotic Leptospira sp. on the human population of the Navarino Island, Maullín, and Ancud districts. The enemy release theory could explain the low helminth species richness in the minks. In addition, we did not find evidence of parasite transmission from native fauna.

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This article presents the design, construction, and evaluation of an easy-to-build textile pressure resistive sensor created from low-cost conventional anti-static sheets and conductive woven fabrics. The sensor can be built quickly using standard household tools, and its thinness makes it especially suitable for wearable applications. Five sensors constructed under such conditions were evaluated, presenting a stable and linear characteristic in the range 1 to 70 kPa. The linear response was modeled and fitted for each sensor individually for comparison purposes, confirming a low variability due to the simple manufacturing process. Besides, the recovery times of the sensors were measured for pressures in the linear range, observing, for example, an average time of 1 s between the moment in which a pressure of 8 kPa was no longer applied, and the resistance variation at the 90% of its nominal value. Finally, we evaluated the proposed sensor design on a classroom application consisting of a smart glove that measured the pressure applied by each finger. From the evaluated characteristics, we concluded that the proposed design is suitable for didactic, healthcare and lifestyle applications in which the sensing of pressure variations, e.g., for activity assessment, is more valuable than accurate pressure sensing.

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Lipids play a central role in cellular function as constituents of membranes, as signaling molecules, and as storage materials. Although much is known about the role of lipids in regulating specific steps of metabolism, comprehensive studies integrating genome-wide expression data, metabolite levels, and lipid levels are currently lacking. Here, we map condition-dependent regulation controlling lipid metabolism in Saccharomyces cerevisiae by measuring 5636 mRNAs, 50 metabolites, 97 lipids, and 57 (13)C-reaction fluxes in yeast using a three-factor full-factorial design. Correlation analysis across eight environmental conditions revealed 2279 gene expression level-metabolite/lipid relationships that characterize the extent of transcriptional regulation in lipid metabolism relative to major metabolic hubs within the cell. To query this network, we developed integrative methods for correlation of multi-omics datasets that elucidate global regulatory signatures. Our data highlight many characterized regulators of lipid metabolism and reveal that sterols are regulated more at the transcriptional level than are amino acids. Beyond providing insights into the systems-level organization of lipid metabolism, we anticipate that our dataset and approach can join an emerging number of studies to be widely used for interrogating cellular systems through the combination of mathematical modeling and experimental biology.

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BACKGROUND: Yeast is considered to be a workhorse of the biotechnology industry for the production of many value-added chemicals, alcoholic beverages and biofuels. Optimization of the fermentation is a challenging task that greatly benefits from dynamic models able to accurately describe and predict the fermentation profile and resulting products under different genetic and environmental conditions. In this article, we developed and validated a genome-scale dynamic flux balance model, using experimentally determined kinetic constraints. RESULTS: Appropriate equations for maintenance, biomass composition, anaerobic metabolism and nutrient uptake are key to improve model performance, especially for predicting glycerol and ethanol synthesis. Prediction profiles of synthesis and consumption of the main metabolites involved in alcoholic fermentation closely agreed with experimental data obtained from numerous lab and industrial fermentations under different environmental conditions. Finally, fermentation simulations of genetically engineered yeasts closely reproduced previously reported experimental results regarding final concentrations of the main fermentation products such as ethanol and glycerol. CONCLUSION: A useful tool to describe, understand and predict metabolite production in batch yeast cultures was developed. The resulting model, if used wisely, could help to search for new metabolic engineering strategies to manage ethanol content in batch fermentations.

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Laboratory strains of Saccharomyces cerevisiae have been widely used as a model for studying eukaryotic cells and mapping the molecular mechanisms of many different human diseases. Industrial wine yeasts, on the other hand, have been selected on the basis of their adaptation to stringent environmental conditions and the organoleptic properties that they confer to wine. Here, we used a two-factor design to study the responses of a standard laboratory strain, CEN.PK113-7D, and an industrial wine yeast strain, EC1118, to growth temperatures of 15 degrees C and 30 degrees C in nitrogen-limited, anaerobic, steady-state chemostat cultures. Physiological characterization revealed that the growth temperature strongly impacted the biomass yield of both strains. Moreover, we found that the wine yeast was better adapted to mobilizing resources for biomass production and that the laboratory yeast exhibited higher fermentation rates. To elucidate mechanistic differences controlling the growth temperature response and underlying adaptive mechanisms between the strains, DNA microarrays and targeted metabolome analysis were used. We identified 1,007 temperature-dependent genes and 473 strain-dependent genes. The transcriptional response was used to identify highly correlated gene expression subnetworks within yeast metabolism. We showed that temperature differences most strongly affect nitrogen metabolism and the heat shock response. A lack of stress response element-mediated gene induction, coupled with reduced trehalose levels, indicated that there was a decreased general stress response at 15 degrees C compared to that at 30 degrees C. Differential responses among strains were centered on sugar uptake, nitrogen metabolism, and expression of genes related to organoleptic properties. Our study provides global insight into how growth temperature affects differential physiological and transcriptional responses in laboratory and wine strains of S. cerevisiae.

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The yeast Saccharomyces cerevisiae is an important industrial microorganism. Nowadays, it is being used as a cell factory for the production of pharmaceuticals such as insulin, although this yeast has long been utilized in the bakery to raise dough, and in the production of alcoholic beverages, fermenting the sugars derived from rice, wheat, barley, corn and grape juice. S. cerevisiae has also been extensively used as a model eukaryotic system. In the last decade, genomic techniques have revealed important features of its molecular biology. For example, DNA array technologies are routinely used for determining gene expression levels in cells under different physiological conditions or environmental stimuli. Laboratory strains of S. cerevisiae are different from wine strains. For instance, laboratory yeasts are unable to completely transform all the sugar in the grape must into ethanol under winemaking conditions. In fact, standard culture conditions are usually very different from winemaking conditions, where multiple stresses occur simultaneously and sequentially throughout the fermentation. The response of wine yeasts to these stimuli differs in some aspects from laboratory strains, as suggested by the increasing number of studies in functional genomics being conducted on wine strains. In this paper we review the most recent applications of post-genomic techniques to understand yeast physiology in the wine industry. We also report recent advances in wine yeast strain improvement and propose a reference framework for integration of genomic information, bioinformatic tools and molecular biology techniques for cellular and metabolic engineering. Finally, we discuss the current state and future perspectives for using 'modern' biotechnology in the wine industry.

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Problematic fermentations are commonplace and cause wine industry producers substantial economic losses through wasted tank capacity and low value final products. Being able to predict such fermentations would enable enologists to take preventive actions. In this study we modeled sugar uptake kinetics and coupled them to a previously developed stoichiometric model, which describes the anaerobic metabolism of Saccharomyces cerevisiae. The resulting model was used to predict normal and slow fermentations under winemaking conditions. The effects of fermentation temperature and initial nitrogen concentration were modeled through an efficiency factor incorporated into the sugar uptake expressions. The model required few initial parameters to successfully reproduce glucose, fructose, and ethanol profiles of laboratory and industrial fermentations. Glycerol and biomass profiles were successfully predicted in nitrogen rich cultures. The time normal or slow wine fermentations needed to complete the process was predicted accurately, at different temperatures. Simulations with a model representing a genetically modified yeast fermentation, reproduced qualitatively well literature results regarding the formation of minor compounds involved in wine complexity and aroma. Therefore, the model also proves useful to explore the effects of genetic modifications on fermentation profiles.

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