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Continuous sensing of biomarkers, such as potassium ions or pH, in wearable patches requires miniaturization of ion-selective sensor electrodes. Such miniaturization can be achieved by using nanostructured carbon materials as solid contacts in microneedle-based ion-selective and reference electrodes. Here we compare three carbon materials as solid contacts: colloid-imprinted mesoporous (CIM) carbon microparticles with â¼24-28 nm mesopores, mesoporous carbon nanospheres with 3-9 nm mesopores, and Super P carbon black nanoparticles without internal porosity but with textural mesoporosity in particle aggregates. We compare the effects of carbon architecture and composition on specific capacitance of the material, on the ability to incorporate ion-selective membrane components in the pores, and on sensor performance. Functioning K+ and H+ ion-selective electrodes and reference electrodes were obtained with gold-coated stainless-steel microneedles using all three types of carbon. The sensors gave near-Nernstian responses in clinically relevant concentration ranges, were free of potentially detrimental water layers, and showed no response to O2. They all exhibited sufficiently low long-term potential drift values to permit calibration-free, continuous operation for close to 1 day. In spite of the different specific capacitances and pore architecture of the three types of carbon, no significant difference in potential stability for K+ ion sensing was observed between electrodes that used each material. In the observed drift values, factors other than the carbon solid contact are likely to play a role, too. However, for pH sensing, electrodes with CIM as a carbon solid contact, which had the highest specific capacitance and best access to the pores, exhibited better long-term stability than electrodes with the other carbon materials.
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Cilia are hair-like organelles present on cell surfaces. They often exhibit a collective wave-like motion that can enhance fluid or particle transportation function, known as metachronal motion. Inspired by nature, researchers have developed artificial cilia capable of inducing metachronal motion, especially magnetic actuation. However, current methods remain intricate, requiring either control of the magnetic or geometrical properties of individual cilia or the generation of a complex magnetic field. In this paper, we present a novel elegant method that eliminates these complexities and induces metachronal motion of arrays of identical microscopic magnetic artificial cilia by applying a simple rotating uniform magnetic field. The key idea of our method is to place arrays of cilia on surfaces with a specially designed curvature. This results in consecutive cilia experiencing different magnetic field directions at each point in time, inducing a phase lag in their motion, thereby causing collective wave-like motion. Moreover, by tuning the surface curvature profile, we can achieve diverse metachronal patterns analogous to symplectic and antiplectic metachronal motion observed in nature, and we can even devise novel combinations thereof. Furthermore, we characterize the local flow patterns generated by the motion of the cilia, revealing the formation of vortical patterns. Our novel approach simplifies the realization of miniaturized metachronal motion in microfluidic systems and opens the possibility of controlling flow pattern generation and transportation, opening avenues for applications such as lab-on-a-chip technologies, organ-on-a-chip platforms, and microscopic object propulsion.
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Cílios , Campos Magnéticos , Propriedades de Superfície , Movimento (Física)RESUMO
The acoustically actuated nanomechanical magnetoelectric (ME) antennas represent a promising new technology that can significantly reduce antenna size by 1-2 orders of magnitude compared to traditional antennas. However, current ME antennas face challenges such as low antenna gain and narrow operating bandwidth, limiting their engineering applications. In this paper, we enhance the bandwidth and radiation performance of ME antennas through structural optimization, leveraging theoretical analysis and numerical simulations. Our findings indicate that optimizing the inner diameter of the ring-shaped ME antenna can elevate the average stress of the magnetic layer, leading to improved radiation performance and bandwidth compared to circular ME antennas. We establish an optimization model for the radiation performance of the ME antenna and conduct shape optimization simulations using COMSOL Multiphysics. The results of the Multiphysics field optimization align with the stress concentration theory, demonstrating a strong correlation between the radiation performance and bandwidth of the ME antenna with the average stress of the magnetic film. The resonant frequency in the thickness vibration mode is determined to be 170 MHz. Furthermore, shape optimization can enhance the bandwidth by up to 104% compared to circular ME antenna structures of the same size.
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The rapid progress of the modern world has resulted in new materials and products created at an accelerating pace. As such, nanoparticles have widespread applications and often find their way into the aquatic ecosystem. In the case of freshwater ecosystems, one of the commonly used bioindicators species used for pollution assessment is Daphnid magna. The Organization for Economic Co-operation and Development (OECD), and other organizations such as the European Chemicals Agency (ECHA) and Environmental Protection Agency (EPA), have set guidelines for acute toxicity testing in daphnids that are severely lacking in terms of information on the characteristics of the exposure vessel when studying the adverse effects of nanoparticles (NPs). Understanding the toxicity mechanisms of nanomaterials is imperative given the scarcity of information on their adverse effects. Furthermore, miniaturization of nanotoxicity assays can reduce the number of daphnids used, as well as the cost and nanomaterial waste, and provide results even at the individual animal level with enhanced reproducibility of testing. In this study, the impact of the exposure vessel on the observed physiological changes of daphnids was investigated for a silver nano ink. Exposures in eleven commercially available vessels; nine made of plastic and two made of glass were compared for 24 h. The effect of surface to volume ratio of the exposure vessel and the animal number or "crowding" during exposure was investigated in the context of miniaturizing biomarker assays as alternatives to traditional experimental setups in Daphnid magna. Toxicity curves showed differences depending on the vessel used, while a novel feeding rate assay and the activity of key enzymes were assessed as physiology endpoints.
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This study introduces a feasible approach for utilizing a conventional High-Performance Liquid Chromatography (HPLC) instrument at the capillary scale (1 - 10 µL/min). The development of an active flow splitter and an adapted UV-visible (UV-vis) detection cell are described. The system employs an Arduino Uno board to monitor a flow sensor and control a stepper motor that automates a split valve to achieve capillary-scale flow rates from a conventional pump. A capillary UV-vis cell compatible with conventional detectors, featuring an optical path length with a volume of 14 nL, was developed to address the detection challenges at this scale and minimize extra column band broadening. The system performance was assessed by a lab-packed LC capillary column with 0.25 mm x 15 cm dimensions packed with 3.0 µm C18 particles. Model compounds, particularly polycyclic aromatic hydrocarbons (PAHs), were employed to assess the functionality of all developed components in terms of theoretical plates, resolution, and band broadening. The proposed system is a profitable, reliable, and cost-effective tool for miniaturized liquid chromatography.
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Hidrocarbonetos Policíclicos Aromáticos , Cromatografia Líquida de Alta Pressão/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Desenho de Equipamento , Espectrofotometria UltravioletaRESUMO
A miniaturized microchip-based absorbance detector was developed for portable high-performance liquid chromatography (HPLC) to test glycated hemoglobin (HbA1c). The microchip integrating a Z-shaped cell, two collimating micro-lenses and two ink-filled optical slits is small in size (30 mm × 15 mm × 7 mm). The Z-shaped cell has a cross-sectional size of 500 µm × 500 µm and a physical optical path length of 2 mm. Two collimating micro-lenses were inserted in empty grooves on both sides of the cell, one micro-lens for collimating the initial light and the other for focusing the transmitted light. Optical slits on each end of the cell were used to block the stray light. Therefore, this detector indicated a low stray light level (0.011 %) and noise level (2.5 × 10-4 AU). This detector was applied for the commercial HPLC system to detect HbA1c level, and showed a low limit of detection (0.5 µg/mL) and excellent repeatability (≤ 2.03 %). The sensitivity was enhanced by 3.4 times when the optical path length was increased from 0.5 mm to 2 mm and the stray light was blocked by optical slits. The miniaturized microchip-based absorbance detector developed shows a great potential for application in portable and compact HPLC.
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Desenho de Equipamento , Hemoglobinas Glicadas , Limite de Detecção , Cromatografia Líquida de Alta Pressão/métodos , Hemoglobinas Glicadas/análise , Humanos , Dispositivos Lab-On-A-Chip , Reprodutibilidade dos TestesRESUMO
BACKGROUND: There is a growing demand for fast and reliable plant biomolecular analyses. DNA extraction is the major bottleneck in plant nucleic acid-based applications especially due to the complexity of tissues in different plant species. Conventional methods for plant cell lysis and DNA extraction typically require extensive sample preparation processes and large quantities of sample and chemicals, elevated temperatures, and multiple sample transfer steps which pose challenges for high throughput applications. RESULTS: In a prior investigation, an ionic liquid (IL)-based modified vortex-assisted matrix solid phase dispersion approach was developed using the model plant, Arabidopsis thaliana (L.) Heynh. Building upon this foundational study, the present study established a simple, rapid and efficient protocol for DNA extraction from milligram fragments of plant tissue representing a diverse range of taxa from the plant Tree of Life including 13 dicots and 4 monocots. Notably, the approach was successful in extracting DNA from a century old herbarium sample. The isolated DNA was of sufficient quality and quantity for sensitive molecular analyses such as qPCR. Two plant DNA barcoding markers, the plastid rbcL and nuclear ribosomal internal transcribed spacer (nrITS) regions were selected for DNA amplification and Sanger sequencing was conducted on PCR products of a representative dicot and monocot species. Successful qPCR amplification of the extracted DNA up to 3 weeks demonstrated that the DNA extracted using this approach remains stable at room temperature for an extended time period prior to downstream analysis. CONCLUSIONS: The method presented here is a rapid and simple approach enabling cell lysis and DNA extraction from 1.5 mg of plant tissue across a broad range of plant taxa. Additional purification prior to DNA amplification is not required due to the compatibility of the extraction solvents with qPCR. The method has tremendous potential for applications in plant biology that require DNA, including barcoding methods for agriculture, conservation, ecology, evolution, and forensics.
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In answer to the demand for high sensitivity and miniaturization of ultra-high frequency (UHF) sensors for partial discharge (PD) detection in power equipment, this paper proposes research on miniaturized UHF-sensing technology for PD detection in power equipment based on symmetric cut theory. The symmetric cut theory is applied for the first time to the miniaturization of PD UHF sensors for power equipment. A planar monopole UHF sensor with a size of only 70 mm × 70 mm × 1.6 mm is developed using an exponential asymptotic feed line approach, which is a 50% size reduction. The frequency-response characteristics of the sensor are simulated, optimized and tested; the results show that the standing wave ratio of the sensor developed in this paper is less than 2 in the frequency band from 427 MHz to 1.54 GHz, and less than 5 in the frequency band from 300 MHz to 1.95 GHz; in the 300 MHz~1.5 GHz band; the maximum and average gains of the sensor E-plane are 4.76 dB and 1.02 dB, respectively. Finally, the PD simulation experiment platform for power equipment is built to test the sensor's sensing performance; the results show that the sensor can effectively detect the PD signals; the sensing sensitivity is improved by about 95% relative to an elliptical monopole UHF sensor.
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Microwave couplers are used in large numbers in beamforming networks, and their miniaturization can lead to a significant size reduction in the overall phased array. While the miniaturization of 3 dB couplers in the transverse direction (width) has been given considerable attention in the literature, there is minimal to no information on reducing coupler length. This is because of the trade-off between aperture length, bandwidth and coupling strength. The Bethe-Hole theory requires adding multiple apertures in the longitudinal direction for wide bandwidth, thus increasing the device length. Another factor is the aperture size, which determines the coupling strength and puts additional strain on the compactness of a 3 dB coupler. Contrariwise, this paper proposes to merge two weak (and hence compact) coupling mechanisms to design a wideband 3 dB coupler. This is achieved by using a longitudinal rectangular slot and three cross-slots in the transverse direction. Because of weak coupling, the slot sizes are smaller than a conventional 3 dB coupler, hence yielding a device whose length is less than one guided wavelength (λg) without compromising the bandwidth. The presented coupler is 0.63 λg in length, which is smaller than the state-of-the-art while maintaining a fractional bandwidth of 37% that is comparable to half-mode substrate integrated waveguide (HMSIW) couplers.
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BACKGROUND: Even though 20% of chronic lateral ankle instability results from a combined anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) injury, only the ATFL is sutured using arthroscopic ligament repair techniques. Although some biomechanical and clinical studies have proved that isolated ATFL repair yields excellent results, previous biomechanical studies were performed using systems that only allow indirect estimations. The purpose of this study was to clarify strain patterns by directly measuring repaired ATFL and CFL strain patterns on cadaveric models that underwent isolated ATFL repair of a combined ATFL and CFL injury. METHODS: The miniaturization ligament performance probe (MLPP) system was used for directly measuring the strain patterns to insert the strain gauges into the mid-substance of normal and repaired ATFL and CFL fibers in five cadaveric specimens to allow measurement of strain patterns in the axial and three-dimensional motion of the ankle. RESULTS: The normal and repaired ATFL showed similar strain patterns in axial and three-dimensional motions. During the axial range of motion of the ankle, the repaired CFL showed a strain pattern almost similar to that of normal CFL, but the strain increased as the plantar flexion or dorsiflexion angle increased to the maximum value of 100 at 30° plantarflexion or strain values of 17-55/100 at 15°dorsiflexion. During three-dimensional motion, the repaired CFL was under the maximum value of 100 during dorsiflexion-inversion and exhibited less strain (7-38/100) during plantar flexion-eversion. CONCLUSION: The repaired CFL did not show a strain pattern that was completely consistent with a normal strain pattern; however, it did have some degree of tension similar to a normal strain pattern, even though it was not directly repaired.
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In this paper, two kinds of miniaturization methods for designing a compact wideband tapered slot antenna (TSA) using either fan-shaped structures only or fan-shaped and stepped structures were proposed. First, a miniaturization method appending the fan-shaped structures, such as quarter circular slots (QCSs), half circular slots (HCSs), and half circular patches (HCPs), to the sides of the ground conductor for the TSA was investigated. The effects of appending the QCSs, HCSs, and HCPs sequentially on the input reflection coefficient and gain characteristics of the TSA were compared. The compact wideband TSA using the first miniaturization method showed the simulated frequency band for a voltage standing wave ratio (VSWR) less than 2 of 2.530-13.379 GHz (136.4%) with gain in the band ranging 3.1-6.9 dBi. Impedance bandwidth was increased by 29.7% and antenna size was reduced by 39.1%, compared to the conventional TSA. Second, the fan-shaped structures combined with the stepped structures (SSs) were added to the sides of the ground conductor to further miniaturize the TSA. The fan-shaped structures based on the HCSs and HCPs were appended to the ground conductor with the QCSs and SSs. The compact wideband TSA using the second miniaturization method had the simulated frequency band for a VSWR less than 2 of 2.313-13.805 GHz (142.6%) with gain in the band ranging 3.0-8.1 dBi. Impedance bandwidth was increased by 37.8% and antenna size was reduced by 45.9%, compared to the conventional TSA. Therefore, the increase in impedance bandwidth and the size reduction effect of the compact wideband TSA using the second miniaturization method were better compared to those using the first method. In addition, sidelobe levels at high frequencies decreased while gain at high frequencies increased. A prototype of the compact wideband TSA using the second miniaturization method was fabricated on an RF-35 substrate to validate the simulation results. The measured frequency band for a VSWR less than 2 was 2.320-13.745 GHz (142.2%) with measured gain ranging 3.1-7.9 dBi.
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Introduction: Engineered 3D models employing human induced pluripotent stem cell (hiPSC) derivatives have the potential to recapitulate the cell diversity and structure found in the human central nervous system (CNS). Therefore, these complex cellular systems offer promising human models to address the safety and potency of advanced therapy medicinal products (ATMPs), such as gene therapies. Specifically, recombinant adeno-associated viruses (rAAVs) are currently considered highly attractive for CNS gene therapy due to their broad tropism, low toxicity, and moderate immunogenicity. To accelerate the clinical translation of rAAVs, in-depth preclinical evaluation of efficacy and safety in a human setting is primordial. The integration of hiPSC-derived CNS models in rAAV development will require, amongst other factors, robust, small-scale, high-throughput culture platforms that can feed the preclinical trials. Methods: Herein, we pioneer the miniaturization and parallelization of a 200 mL stirred-tank bioreactor-based 3D brain cell culture derived from hiPSCs. We demonstrate the applicability of the automated miniaturized Ambr® 15 Cell Culture system for the maintenance of hiPSC-derived neurospheroids (iNSpheroids), composed of neuronal and glial cells. Critical process parameters were optimized, namely, cell density and agitation mode. Results: Under optimized conditions, stable iNSpheroid cultures were attained in the microbioreactors for at least 15 days, with high cell viability and astrocytic and neuronal phenotype maintenance. This culture setup allowed the parallelization of different rAAVs, in different multiplicity of infections (MOIs), to address rAAV-host interactions at a preclinical scale. The iNSpheroids were exposed to rAAV2- and rAAV9-eGFP in the microbioreactors. Transgene expression was detected 14 days post-transduction, revealing different astrocyte/neuron tropism of the two serotypes. Discussion: We advocate that the iNSpheroid cultures in miniaturized bioreactors are reliable and reproducible screening tools for addressing rAAV transduction and tropism, compatible with preclinical demands.
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IoT is a game-changer across all fields, including chemistry. Embracing sustainable practices and green chemistry, the miniaturization and automation of systems, and their integration into IoT is key to achieving these principles, as a rising trend with momentum. Particularly, IoT and analytical chemistry are linked in the rapid exchange of analytical data for environmental, industrial, healthcare, and educational applications. Meanwhile, cooperation with other fields of science is evident, and there is a prompt and subjective analysis of information related to analytical systems and methodologies. This paper will review the concepts, requirements, and architecture of IoT and its role in the miniaturization and automation of analytical tools using electronic modules and sensors. The aim is to explore the standards and perspectives of IoT and its interaction with different aspects of analytical chemistry. Additionally, it aimed to explain the basics and applications of IoT for chemists, and its relevance to different subfields of analytical chemistry, particularly in the field of environmental chemical surveillance. The article also covers updating IoT devices and creating DIY-based degradation devices to enhance the educational aspect of chemistry and reduce barriers to lab facilities and equipment. Lastly, it will explore how IoT is really important and how it's going to significantly impact analytical chemistry.
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Monitoramento Ambiental , Internet das Coisas , Miniaturização , Monitoramento Ambiental/métodosRESUMO
Ergot alkaloids, naturally occurring mycotoxins of Claviceps fungi, pose health risks. This necessitates accurate analysis methods to ensure food safety. This study explored the open-source miniaturized all-in-one 2LabsToGo system to analyze ergot alkaloids in whole rye samples. It is suited for sustainable atline analysis as it combines all planar chromatography tasks, allowing low-cost quality control in milling plants. The LOD and LOQ of ergocristine were determined to be 0.4 and 1.2 ng/zone, respectively. Detectability of ergot alkaloids was proven to be below the current maximum limit of 500 µg/kg for rye milling products. The repeatability (%RSD) was 4.1 % and the coefficient of determination of the analytical response (R2) was 0.9918 for ergocristine. The mean recovery rate of ergot alkaloids in spiked whole rye grain was close to 100 %. Results of screening whole rye for ergot alkaloids were successfully verified by comparison with those obtained by conventional status quo HPTLC instrumentation.
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Alcaloides de Claviceps , Contaminação de Alimentos , Secale , Secale/química , Alcaloides de Claviceps/análise , Contaminação de Alimentos/análise , Cromatografia Líquida de Alta Pressão , Micotoxinas/análise , Claviceps/química , Limite de DetecçãoRESUMO
Mass spectrometry is characterized by its high sensitivity, ability to measure very low analyte concentrations, specificity to distinguish between closely related compounds, availability to generate high-throughput methods for screening, and high multiplexing capacity. This technique has been used as a platform to analyze fluid biomarkers for Alzheimer's disease. However, more effective sample preparation procedures, preferably antibody-independent, and more automated mass spectrometry platforms with improved sensitivity, chromatographic separation, and high throughput are needed for this purpose. This short communication discusses the development of a fiber-in-tube SPME-CapLC-MS/MS method to determine Aß peptides in cerebrospinal fluid obtained from Alzheimer's disease patients. To obtain the fiber-in-tube SPME capillary, we longitudinally packed 22 nitinol fibers coated with a zwitterionic polymeric ionic liquid into the same length of the PEEK tube. In addition, this communication compares this fiber-in-tube SPME method with the conventional HPLC scale (HPLC-MS/MS) and when directly coupled to CapESI-MS/MS without chromatographic separation, and, as a case study, discusses the benefits and challenges inherent in miniaturizing the flow scale of the sample preparation technique (fiber-in-tube SPME) to the CapLC-MS/MS system. Fiber-in-tube SPME-CapLC-MS/MS provided LLOQ ranging from 0.09 to 0.10 ng mL-1, accuracy ranging from 91 to 117â¯% (recovery), and reproducibility of less than 18â¯% (RSD). Analysis of the cerebrospinal fluid samples obtained from Alzheimer's disease patients evidenced that the method is robust. At the capillary scale (10 µL min-1), this innovative method presented higher analytical sensitivity than the conventional HPLC-MS/MS scale. Although fiber-in-tube SPME directly coupled to CapESI-MS/MS offers advantages in terms of high throughput, the sample was dispersed and non-quantitatively desorbed from the capillary at low flow rate. These results highlighted that chromatographic separation is important to decrease the matrix effect and to achieve higher detectability, which is indispensable for bioanalysis.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Microextração em Fase Sólida , Espectrometria de Massas em Tandem , Doença de Alzheimer/líquido cefalorraquidiano , Humanos , Espectrometria de Massas em Tandem/métodos , Microextração em Fase Sólida/métodos , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/análise , Reprodutibilidade dos TestesRESUMO
Since the last decades, light has been shed on the pollution of aquatic ecosystems. Considering apolar compounds in water, analysis of the dissolved phase is not sufficient due to their possible bioaccumulation. Additional analysis of sediments, biota, or sentinel species is necessary. Among sentinel species, Gammarus fossarum is a small shrimp of 30 mg that lives naturally in the river. Its ability to bioaccumulate makes it a good bioindicator of river pollution. Nevertheless, micropollutants are difficult to extract from gammarids due to their small size and their high level of lipids. Extracted interferences can lead to analytical difficulties. Targeted micropollutants in this work were organotins, personal and pharmaceutical care products (PPCPs), pesticides, flame retardants, and perfluorinated compounds. A sample preparation based on QuEChERS followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was developed: different salts (acetate and citrate) and purification (addition of hexane, dispersive SPE) were tested and validated. Targeted molecules used to be analyzed by LC-MS/MS, except organotins which are principally analyzed in gas chromatography. One of the main challenges was to quantify them also in LC-MS/MS to implement an original multi-residue method. The analysis of 40 compounds was finally validated according to ICH guidelines, with LOQs ranging from 0.04 ng.g-1 to 313.5 ng.g-1. Regarding Perfluorooctanesulfonic acid (PFOS) and the sum of hexabromocyclododecane, LOQs reached the environmental quality standards in biota which are respectively of 9.1 and 167 ng.g-1. Finally, the method was applied to 15 real samples. Many compounds were quantified: perfluorinated compounds, drugs such as ketoprofen, and even cosmetics products such as octocrylene. This is the first study to quantify as many emerging compounds, especially organotins, in a sentinel species such as G. fossarum.
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Ecossistema , Espectrometria de Massas em Tandem , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massa com Cromatografia Líquida , Extração em Fase SólidaRESUMO
Compact high-frequency arrays are of interest for clinical and preclinical applications in which a small-footprint or endoscopic device is needed to reach the target anatomy. However, the fabrication of compact arrays entails the connection of several dozens of small elements to the imaging system through a combination of flexible printed circuit boards at the array end and micro-coaxial cabling to the imaging system. The methods currently used, such as wire bonding, conductive adhesives, or a dry connection to a flexible circuit, considerably increase the array footprint. Here, we propose an interconnection method that uses vacuum-deposited metals, laser patterning, and electroplating to achieve a right-angle, compact, reliable connection between array elements and flexible-circuit traces. The array elements are thickened at the edges using patterned copper traces, which increases their cross-sectional area and facilitates the connection. We fabricated a 2.3 mm by 1.7 mm, 64-element linear array with elements at a 36 µm pitch connected to a 4 cm long flexible circuit, where the interconnect adds only 100 µm to each side of the array. Pulse-echo measurements yielded an average center frequency of 55 MHz and a -6 dB bandwidth of 41%. We measured an imaging resolution of 35 µm in the axial direction and 114 µm in the lateral direction and demonstrated the ex vivo imaging of porcine esophageal tissue and the in vivo imaging of avian embryonic vasculature.
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Transdutores , Animais , Suínos , Desenho de Equipamento , Ultrassonografia , Imagens de Fantasmas , Impedância ElétricaRESUMO
This paper presents a waveguide Lens antenna at the W-band adopting dual-focusing Lens to improve the performance. The Lens antenna consisted of a waveguide slotted structure and lenses processed using NOA73 meet the demands of miniaturization for current communication systems. The antenna radome fabricated using NOA73 not only protects the antenna structure but also improves the gain of the antenna by about 9.5 dBi via electromagnetic wave dual-focusing. A prototype is fabricated using novel UV-LIGA technology. Measured results are compared with simulated values. Measured results confirmed the fabricated antenna operated in the W-band with a 10 dB fractional bandwidth (FBW) of 6.5% from 97.5 to 104 GHz and a peak gain of 22 dBi at 100 GHz in the direction perpendicular to the plane of the feed waveguide. A good agreement between simulation and measurement is obtained, demonstrating efficient radiations in the operating band.
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Continuous chromatography has emerged as one of the most attractive methods for protein purification. Establishing such systems involves installing several chromatographic units in series to enable continuous separation processes and reduce the cost of the production of expensive proteins and biopharmaceuticals (such as monoclonal antibodies). However, most of the established systems are bulky and plagued by high dead volume, which requires further optimization for improved separation procedures. In this article, we present a miniaturized periodic counter-current chromatography (PCCC) system, which is characterized by substantially reduced dead volume when compared to traditional chromatography setups. The PCCC device was fabricated by 3D printing, allowing for flexible design adjustments and rapid prototyping, and has great potential to be used for the screening of optimized chromatography conditions and protocols. The functionality of the 3D-printed device was demonstrated with respect to the capture and polishing steps during a monoclonal antibody purification process. Furthermore, this novel miniaturized system was successfully used for two different chromatography techniques (affinity and ion-exchange chromatography) and two different types of chromatographic units (columns and membrane adsorbers). This demonstrated versability underscores the flexibility of this kind of system and its potential for utilization in various chromatography applications, such as direct product capture from perfusion cell cultures.
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Extracorporeal membrane oxygenation (ECMO) has evolved into a pivotal intervention in critical care, offering a lifeline for patients facing severe respiratory or cardiac failure. This review provides a comprehensive exploration of ECMO, spanning its definition and historical background to its contemporary advancements and ongoing impact in critical care. The versatility of ECMO in addressing diverse critical conditions, careful patient selection criteria, and the nuanced management of complications are discussed. Advances in technology, including miniaturization, novel circuit designs, and the integration of remote monitoring, showcase the evolving landscape of ECMO. The review underscores the ongoing impact of ECMO in improving survival rates, enhancing mobility, and enabling remote expertise. As a symbol of hope and innovation, ECMO's lifesaving potential is evident in its ability to navigate the complexities of critical care and redefine the boundaries of life support interventions.