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The presence of hexavalent chromium species (CrVI) in wastewater from manufacturing industries such as electroplating and leather production can pose serious health hazards. To address these concerns, this study developed a novel adsorbent based on activated carbon as the primary material to attract CrVI. Activated carbon has been modified with several other components to improve its comprehensive performance, including adsorption capacity, chemical stability, collectability, and reusability. Specifically, decoration with magnetite nanoparticles made it possible to collect the adsorbent magnetically and reuse it several times. On the one hand, the addition of chitosan not only increased the chemical stability of activated carbon, especially under acidic conditions, but also enhanced the Cr adsorption capacity at pH higher than 4, where adsorption of only activated carbon was significantly decreased, probably because the protonated amino groups attracted chromate anions. In addition, the co-existence of tannic acid did not increase the adsorption capacity significantly but appeared to promote the reductive adsorption of CrVI, where the reduction of CrVI means lowering the toxicity of Cr species. It was demonstrated that activated carbon modified with magnetite, chitosan, and tannic acid exhibited superior comprehensive performance that could be repeatedly used over a wide pH range as compared to the parent activated carbon.
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The case of a 72-year-old female patient with arrhythmogenic syncope associated with a combination therapy of flecainide and lacosamide is presented. The authors believe in an additive effect of both drugs on myocardial voltage-gated sodium channels with extraordinary QRS widening, exit block with temporary pacing and complete reversibility through infusion of sodium bicarbonate as bail-out therapy.
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3D-printing technology allows scientist to fabricate easily electrochemical sensors. Until now, these sensors were designed employing a large amount of material, which increases the cost and decreases manufacturing throughput. In this work, a low-cost 3D-printed on-drop electrochemical sensor (3D-PES) was fully manufactured by fused filament fabrication, minimizing the number of printing layers. Carbon black/polylactic acid filament was employed, and the design and several printing parameters were optimized to yield the maximum electroanalytical performance using the minimal amount of material. Print speed and extrusion width showed a critical influence on the electroanalytical performance of 3D-PES. Under optimized conditions, the fabrication procedure offered excellent reproducibility (RSD 1.3% in working electrode diameter), speed (< 3 min/unit), and costs (< 0.01 $ in material cost). The 3D-PES was successfully applied to the determination of phloridzin in apple juice. The analytical performance of 3D-PES was compared with an equivalent commercial on-drop screen-printed electrode, yielding similar precision and accuracy but lower sensitivity. However, 3D-PES provides interesting features such as recyclability, biodegradability, low-cost, and the possibility of being manufactured near the point of need, some of which meets several demands of Green Chemistry. This cost-effective printing approach is a green and promising alternative for manufacturing disposable and portable electroanalytical devices, opening new possibilities not only in on-site food analysis but also in point-of-care testing.
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Técnicas Electroquímicas , Análisis de los Alimentos , Jugos de Frutas y Vegetales , Poliésteres , Impresión Tridimensional , Hollín , Hollín/química , Poliésteres/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/economía , Jugos de Frutas y Vegetales/análisis , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/economía , Análisis de los Alimentos/métodos , Electrodos , Malus/química , Análisis Costo-Beneficio , Límite de DetecciónRESUMEN
UV sensing 3D printed optical fiber hydrogels provide a flexible and precise method of remotely of detecting exposure to UV radiations. The optical fibers were created using digital light processing 3D printing technique with hydrogel composites, including micro-sized photochromic dyes (pink, blue and their combination). When exposed to ultraviolet (UV) radiation, these dyes exhibited specific absorption characteristics, resulting in significant decreases in both reflection and transmittance mode spectra at 560 nm, 620 nm, and 590 nm. Optical fibers of lengths 1, 2, and 3 cm were manufactured in two orientations: vertical and horizontal. Scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction were utilized to characterize the printed fiber probes. The optical performance of the fibers was tested using customized measurement setups. The reflection and transmission of the printed fibers reduced as the length increased due to optical losses. Reflection and transmisson loss of 20-40% can be observed when the length is increased from 1 to 3 cm. The maximum loss in reflection is observed for pink fiber in the presence of UV irradiation. Also, the type of powder used impacted the response and retraction time, whereas the mixed fiber showed the highest response time of 12-20 s under various conditions. The pink dye added fiber probes shows quick response to UV radiation. An increase in the response time is observed with increasing fiber length. The impact of printing orientation on the transmission and reflectance mode operations of optical fibers was assessed. In addition, the stability of the fiber probes are assesed using a green laser having wavelength 532 nm. This work comprehensively examines the optical properties, manufacturing procedures, and sensing capacities of UV-sensitive photochromic optical fiber sensors.
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With the increased availability of chemical data in public databases, innovative techniques and algorithms have emerged for the analysis, exploration, visualization, and extraction of information from these data. One such technique is chemical grouping, where chemicals with common characteristics are categorized into distinct groups based on physicochemical properties, use, biological activity, or a combination. However, existing tools for chemical grouping often require specialized programming skills or the use of commercial software packages. To address these challenges, we developed a user-friendly chemical grouping workflow implemented in KNIME, a free, open-source, low/no-code, data analytics platform. The workflow serves as an all-encompassing tool, expertly incorporating a range of processes such as molecular descriptor calculation, feature selection, dimensionality reduction, hyperparameter search, and supervised and unsupervised machine learning methods, enabling effective chemical grouping and visualization of results. Furthermore, we implemented tools for interpretation, identifying key molecular descriptors for the chemical groups, and using natural language summaries to clarify the rationale behind these groupings. The workflow was designed to run seamlessly in both the KNIME local desktop version and KNIME Server WebPortal as a web application. It incorporates interactive interfaces and guides to assist users in a step-by-step manner. We demonstrate the utility of this workflow through a case study using an eye irritation and corrosion dataset.Scientific contributionsThis work presents a novel, comprehensive chemical grouping workflow in KNIME, enhancing accessibility by integrating a user-friendly graphical interface that eliminates the need for extensive programming skills. This workflow uniquely combines several features such as automated molecular descriptor calculation, feature selection, dimensionality reduction, and machine learning algorithms (both supervised and unsupervised), with hyperparameter optimization to refine chemical grouping accuracy. Moreover, we have introduced an innovative interpretative step and natural language summaries to elucidate the underlying reasons for chemical groupings, significantly advancing the usability of the tool and interpretability of the results.
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BACKGROUND: Food safety has become an essential aspect of public concern and there are lots of detection means. Liquid chromatography plays a dominating role in food safety inspection because of its high separation efficiency and reproducibility. However, with the increasing complexity of real samples and monitoring requirements, conventional single-mode chromatography would require frequent column replacement and cannot separate different kinds of analytes on a single column simultaneously, which is costly and time-consuming. There is a great need for fabricating mixed-mode stationary phases and validating the feasibility of employing mixed-mode stationary phases for food safety inspection. RESULTS: This work fabricated multifunctional stationary phases for liquid chromatography to determine diverse food additives under the mixed mode of RPLC/HILIC/IEC. Two dicationic ionic liquid silanes were synthesized and bonded onto the silica gel surface. The functionalized silica was characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and elemental analysis. Both columns provide satisfactory separation performance towards 6 hydrophilic nucleosides, 4 hydrophobic polycyclic aromatic hydrocarbons, and 5 anions. Great repeatability of retention (RSD <0.1 %) and column efficiency (100330 plate/m) were obtained. Thermomechanical analysis and linear solvation energy relationship investigated the retention mechanism. Finally, the better in two prepared columns was employed to separate and determine the contents of NO2- and NO3- in vegetables(highest 4906 mg kg-1 NO3- in spinach), preservatives in bottled beverages (180.8 mg kg-1 sodium benzoate in soft drink), and melamine in milk with satisfactory performance and recovery rates ranging from 96.4 % to 105.6 %. SIGNIFICANCE: This work developed a novel scheme for preparing mixed-mode stationary phases by dicationic ionic liquid which provides great separation selectivity. Most importantly, this work proved the superiority of employing mixed-mode stationary phases for food safety inspection, which might avoid high-cost and frequent changes of columns and chromatography systems in the near future.
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Aditivos Alimentarios , Líquidos Iónicos , Dióxido de Silicio , Líquidos Iónicos/química , Dióxido de Silicio/química , Aditivos Alimentarios/análisis , Aditivos Alimentarios/aislamiento & purificación , Cromatografía Liquida/métodos , Nucleósidos/aislamiento & purificación , Nucleósidos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Aniones/análisis , Aniones/aislamiento & purificación , Aniones/química , Silanos/químicaRESUMEN
The high electrochemical reactivity of H2O molecules and zinc metal results in severe side reactions and dendrite formation on zinc anodes. Here we demonstrate that these issues can be addressed by using N-hydroxymethylacetamide (NHA) as additives in 2 M ZnSO4 electrolytes. The addition of NHA molecules, acting as both a hydrogen bond donor and acceptor, enables the formation of cyclic hydrogen bonding with H2O molecules. This interaction disrupts the existing hydrogen bonding networks between H2O molecules, hindering proton transport, and containing H2O molecules within the cyclic hydrogen bonding structure to prevent deprotonation. Additionally, NHA molecules show a preference for adsorption on the (101) crystal surface of zinc metal. This preferential adsorption reduces the surface energy of the (101) plane, facilitating the homogeneous Zn deposition along the (101) direction. Thus, the NHA enables Zn||Zn symmetric cell with a cycle lifespan of 1100 hours at 5 mA cm-2 and Zn||Cu asymmetric cell with a high Coulombic efficiency over 99.5%. Moreover, the NHA-modified Zn||AC zinc ion hybrid capacitor is capable of sustaining 15000 cycles at 2 A g-1. This electrolyte additive engineering presents a promising strategy to enhance the performance and broaden the application potential of zinc metal-based energy storage devices.
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Monosodium glutamate (MSG) is used as a common food additive in some foods. However, based on our search and knowledge, no comprehensive study discussed the effect of MSG on the human gut microbiome. In this study, the effects of MSG on the gut microbiome, liver, and kidney were performed. Data were collected from databases including PubMed, Scopus, Web of Science, and ScienceDirect using the search strategy and keywords. Finally, 14 eligible studies were selected for systematic review. This study provides a new perspective on the effects of MSG on the gut flora, shedding light on the potential relationship between MSG intake and human health.
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In this study, three different groups of sausages were produced from thornback ray (Raja clavata) without additives (control group), waste pomegranate peel extract (natural group), and ascorbic acid (synthetic group). Biochemical, physicochemical, and microbiological changes of sausages were examined under refrigerator conditions (+4°C), and the shelf life was determined. The best results in terms of nutritional and physicochemical values were obtained in sausages treated with pomegranate peel extract. All sausage groups were spoiled on the 15th day in terms of the total volatile basic nitrogen (TVB-N); however, the pomegranate peel extract group showed a more positive effect compared to the other sausage groups. However, this value was not considered because cartilaginous fish such as stingrays contain higher levels of nonprotein nitrogenous compounds. It was observed that microbial growth was less in the natural group and the antimicrobial effect of pomegranate peel extract was higher than that of ascorbic acid. In addition, it was determined that the pomegranate peel extract group extended the shelf life up to 6 days in terms of total viable count (TVC) and yeast/mold compared to the control and synthetic groups, respectively. This study showed that pomegranate peel extract has a better protective effect than ascorbic acid and it can be used as a natural additive in preserving the quality of seafood products.
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Manufacturing of copper micro-patterns is crucial in electronics for its utilization as high conductivity transparent conductive films (TCFs) and circuits. In the preparation process of current TCFs, a plethora of materials have emerged that can replace traditional indium tin oxide (ITO). However, even for the most promising metal-based nanowire materials, there are issues such as high cost, complex welding, and high contact resistance. To address these problems, this paper proposes a printable and filament-drawable polydimethylsiloxane (PDMS)-based adhesive, which, through a novel additive patterning technology, efficiently and economically manufactures self-welding copper micro-meshes and circuits. The adhesive can be processed into micro-patterns through printing and filament drawing, on which ionic Ag can be in situ reduced and anchored, thereby eliminating the need for tedious pre- and post-treatment steps. The fully exposed Ag particles dramatically minimize the usage of precious metal catalyst, thus efficiently catalyzing electroless copper deposition (ECD) reaction. Highly conductive (1.03 × 107 S m-1) copper circuits can be fabricated on the printed adhesive patterns, exhibiting versatile applicability to diverse substrates. Highly precise copper micro-meshes (â¼50 µm) can be fabricated on the filament networks drawn by the adhesive. The copper meshes undergo complete self-welding at junctions during the ECD process, thus exhibiting ultra-low square resistance of 0.45 Ω sq-1 while maintaining a high transmittance of 82.2 %. This is far superior to most of TCFs in published literature.
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OBJECTIVE: This study aims to design and fabricate a 3D printed heterogeneous paediatric head phantom and to customize a thorax phantom for radiotherapy dosimetry. Approach: This study designed, fabricated, and tested 3D printed radiotherapy phantoms that can simulate soft tissue, lung, brain, and bone. Various polymers were considered in designing the phantoms. Polylactic acid+, nylon, and plaster were used in simulating different tissue equivalence. Dimensional accuracy, and CT number were investigated. The phantoms were subjected to a complete radiotherapy clinical workflow. Several treatment plans were delivered in both the head and the thorax phantom from a simple single 6 MV beam, parallel opposed beams, and five-field intensity modulated radiotherapy (IMRT) beams. Dose measurements using an ionization chamber and radiochromic films were compared with the calculated doses of the Varian Eclipse treatment planning system (TPS). Main results: The fabricated heterogeneous phantoms represent paediatric human head and adult thorax based on its radiation attenuation and anatomy. The measured CT number ranges are within -786.23 ± 10.55, 0.98 ± 3.86, 129.51 ± 12.83, and 651.14 ± 47.76 HU for lung, water/brain, soft tissue, and bone, respectively. It has a good radiological imaging visual similarity relative to a real human head and thorax depicting soft tissue, lung, bone, and brain. The accumulated dose readings for both conformal radiotherapy and IMRT match with the TPS calculated dose within ±2% and ±4% for head and thorax phantom, respectively. The mean pass rate for all the plans delivered are above 90% for gamma analysis criterion of 3% / 3 mm. Significance and conclusion: The fabricated heterogeneous paediatric head and thorax phantoms are useful in Linac end-to-end radiotherapy quality assurance based on its CT image and measured radiation dose. The manufacturing and dosimetry workflow of this study can be utilized by other institutions for dosimetry and trainings. .
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OBJECTIVE: To investigate the potential of 3D-printable thermoplastics as tissue-equivalent materials to be used in multimodal radiotherapy end-to-end quality assurance (QA) devices. APPROACH: Six thermoplastics were investigated: Polylactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), Polyethylene Terephthalate Glycol (PETG), Polymethyl Methacrylate (PMMA), High Impact Polystyrene (HIPS) and StoneFil. Measurements of mass density (ρ), Relative Electron Density (RED), in a nominal 6MV photon beam, and Relative Stopping Power (RSP), in a 210MeV proton pencil-beam, were performed. Average Hounsfield Units (HU) were derived from CTs acquired with two independent scanners. The calibration curves of both scanners were used to predict average ρ, RED and RSP values and compared against the experimental data. Finally, measured data of ρ, RED and RSP was compared against theoretical values estimated for the thermoplastic materials and biological tissues. MAIN RESULTS: Overall, good ρ and RSP CT predictions were made; only PMMA and PETG showed differences >5%. The differences between experimental and CT predicted RED values were also <5% for PLA, ABS, PETG and PMMA; for HIPS and StoneFil higher differences were found (6.94% and 9.42/15.34%, respectively). Small HUs variations were obtained in the CTs for all materials indicating good uniform density distribution in the samples production. ABS, PLA, PETG and PMMA showed potential equivalency for a variety of soft tissues (adipose tissue, skeletal muscle, brain and lung tissues, differences within 0.19% - 8.35% for all properties). StoneFil was the closest substitute to bone, but differences were >10%. Theoretical calculations of all properties agreed with experimental values within 5% difference for most thermoplastics. SIGNIFICANCE: Several 3D-printed thermoplastics were promising tissue-equivalent materials to be used in devices for end-to-end multimodal radiotherapy QA and may not require corrections in treatment planning systems' dose calculations. Theoretical calculations showed promise in identifying thermoplastics matching target biological tissues before experiments are performed.
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The stability of aqueous zinc metal batteries is significantly affected by side reactions and dendrite growth on the anode interface, which primarily originate from water and anions. Herein, we introduce a multi H-bond site additive, 2, 2'-Sulfonyldiethanol (SDE), into an aqueous electrolyte to construct a sieving-type electric double layer (EDL) by hydrogen bond interlock in order to address these issues. On the one hand, SDE replaces H2O and SO42- anions that are adsorbed on the zinc anode surface, expelling H2O/SO42- from the EDL and thereby reducing the content of H2O/SO42- at the interface. On the other hand, when Zn2+ are de-solvated at the interface during the plating, the strong hydrogen bond interaction between SDE and H2O/SO42- can trap H2O/SO42- from the EDL, further decreasing their content at the interface. This effectively sieves them out of the zinc anode interface and inhibits the side reactions. Moreover, the unique characteristics of trapped SO42- anions can restrict their diffusion, thereby enhancing the transference number of Zn2+ and promoting dendrite-free deposition and growth of Zn. Consequently, utilizing an SDE/ZnSO4 electrolyte enables excellent cycling stability in Zn//Zn symmetrical cells and Zn//MnO2 full cells with lifespans exceeding 3500 h and 2500 cycles respectively.
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Current additive manufacturing (AM) techniques for tungsten, such as powder bed fusion and directed energy deposition, often generate parts with rough surfaces. Vat photopolymerization presents a promising alternative for fabricating tungsten structures with high shape fidelity and low surface roughness. However, existing vat photopolymerization approaches suffer from surface defects and low final density, leading to compromised mechanical properties. Therefore, achieving high-density tungsten structures using vat photopolymerization remains a crucial challenge. This work presents a straightforward and reliable method for fabricating complex, micro-architected tungsten structures with superior density and hardness. The approach utilizes a water-based photoresin with exceptional tungsten ion loading capacity. The photoresin is then patterned using digital light processing (DLP) to create tungsten-laden precursors. A three-step debinding and sintering process subsequently achieves 3D tungsten structures with dense surface morphology and minimal internal defects. The microstructures achieve a minimum feature size of 35 µm, a low surface roughness of 2.86 µm, and demonstrate exceptional mechanical properties. This new method for structuring tungsten opens doors to a broad range of applications, including micromachining, collimators, detectors, and metamaterials.
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Modifying catalyst surface with small molecular-additives presents a promising avenue for enhancing electrocatalytic performance. However, challenges arise in preserving the molecular-additives and maximizing their tuning effect, particularly at high current-densities. Herein, we develop an effective strategy to preserve the molecular-additives on electrode surface by applying a thin protective layer. Taking 4-dimethylaminopyridine (DMAP) as an example of a molecular-additive, the hydrophobic protection layer on top of the DMAP-functionalized Cu-catalyst effectively prevents its leaching during CO2 electroreduction (CO2R). Consequently, the confined DMAP molecules substantially promote the CO2-to-multicarbon conversion at low overpotentials. For instance, at a potential as low as -0.47 V vs. reversible hydrogen electrode, the DMAP-functionalized Cu exhibits over 80% selectivity towards multi-carbon products, while the pristine Cu shows only ~35% selectivity for multi-carbon products. Notably, ethanol appears as the primary product on DMAP-functionalized Cu, with selectivity approaching 50% at a high current density of 400 mA cm-2. Detailed kinetic analysis, in-situ spectroscopies, and theoretical calculations indicate that DMAP-induced electron accumulations on surface Cu-sites decrease the reaction energy for C-C coupling. Additionally, the interactions between DMAP and oxygenated intermediates facilitate the ethanol formation pathway in CO2R. Overall, this study showcases an effective strategy to guide future endeavors involving molecular tuning effects.
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We present the R package galamm, whose goal is to provide common ground between structural equation modeling and mixed effect models. It supports estimation of models with an arbitrary number of crossed or nested random effects, smoothing splines, mixed response types, factor structures, heteroscedastic residuals, and data missing at random. Implementation using sparse matrix methods and automatic differentiation ensures computational efficiency. We here briefly present the implemented methodology, give an overview of the package and an example demonstrating its use.
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The consumption of poultry products contaminated with Salmonella species is one of the most common causes of Salmonella infections. In vivo studies demonstrated the potential application of peanut skins (PS) as an antimicrobial poultry feed additive to help mitigate the proliferation of Salmonella in poultry environments. Tons of PS, a waste by-product of the peanut industry, are generated and disposed in U.S. landfills annually. Peanut skins and extracts have been shown to possess antimicrobial and antioxidant properties. Hence, we aimed to determine the effect of PS as a feed additive on the gut microbiota of broilers fed a control or PS supplemented (4% inclusion) diet and inoculated with or without Salmonella enterica Enteritidis (SE). At hatch 160 male broilers were randomly assigned to 4 treatments: 1) CON-control diet without SE, 2) PS-PS diet without SE, 3) CONSE-control diet with SE, 4) PSSE-PS diet with SE. On d 3, birds from CONSE and PSSE treatments were inoculated with 4.2 × 109 CFU/mL SE. At termination (4 wk), 10 birds/treatment were euthanized and ileal and cecal contents were collected for 16S rRNA analysis using standard methodologies. Sequencing data were analyzed using QIIME2. No effect of PS or SE was observed on ileal alpha and beta diversity, while evenness, richness, number of amplicon sequence variants (ASV) and Shannon, as well as beta diversity were significantly (P < 0.05) affected in ceca. Similarly, more differentially abundant taxa between treatment groups were identified in ceca than in ileum. However, more microbiota functional changes, based on the PICRUST2 prediction, were observed in ileum. Overall, relatively minor changes in microbiota were observed during SE infection and PS treatment, suggesting that PS addition may not attenuate the SE proliferation, as shown previously, through modulation of microbiota in gastrointestinal tract. However, while further studies are warranted, these results suggest that PS may potentially serve as a functional feed additive for poultry for improvement of animal health.
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Shaping hard and brittle materials, e.g. cermets, at micrometer resolution has long been known challenging for both mechanical machining and high energy beam based additive manufacturing. Digital light processing (DLP), which features great printing quality and decent precision, unfortunately lacks capability to deal with the popular slurry-typed cermet precursor due to the tremendous optical absorption by its particles. Here, an innovative protocol based on a versatile collapsable matrix is devised to allow high-precision printing of WC-Co cermets on DLP platform. By tuning the external environment, this matrix attenuates composite powders to facilitate photopolymerization at the printing stage, and shrinks to condense green parts prior to thermal sintering. The as-obtained samples by collapsable matrix assisted DLP can reach a relative density of ≈90%, a record-breaking resolution of ≈10 µm, and a microhardness of up to 14.5 GPa. Complex delicate structures, including school emblem, honeycomb, and micro-drill can be directly fabricated, which has never been achieved before. Impressively, the as-obtained micro-drill is able to be directly used in drilling tasks. The above strategy represents a great progress in DLP by enabling shaping strong light attenuating materials at high resolution. Such advantages are ideal for the next generation ceramic-metal composite additive manufacturing.
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Analysis of the restricted mean survival time (RMST) has become increasingly common in biomedical studies during the last decade as a means of estimating treatment or covariate effects on survival. Advantages of RMST over the hazard ratio (HR) include increased interpretability and lack of reliance on the often tenuous proportional hazards assumption. Some authors have argued that RMST regression should generally be the frontline analysis as opposed to methods based on counting process increments. However, in order for the use of the RMST to be more mainstream, it is necessary to broaden the range of data structures to which pertinent methods can be applied. In this report, we address this issue from two angles. First, most of existing methodological development for directly modeling RMST has focused on multiplicative models. An additive model may be preferred due to goodness of fit and/or parameter interpretation. Second, many settings encountered nowadays feature high-dimensional categorical (nuisance) covariates, for which parameter estimation is best avoided. Motivated by these considerations, we propose stratified additive models for direct RMST analysis. The proposed methods feature additive covariate effects. Moreover, nuisance factors can be factored out of the estimation, akin to stratification in Cox regression, such that focus can be appropriately awarded to the parameters of chief interest. Large-sample properties of the proposed estimators are derived, and a simulation study is performed to assess finite-sample performance. In addition, we provide techniques for evaluating a fitted model with respect to risk discrimination and predictive accuracy. The proposed methods are then applied to liver transplant data to estimate the effects of donor characteristics on posttransplant survival time.
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Modelos Estadísticos , Humanos , Análisis de Supervivencia , Trasplante de Hígado , Modelos de Riesgos Proporcionales , Biometría/métodosRESUMEN
Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on Loigolactobacillus coryniformis DSM 34345 when used as a technological additive to improve ensiling of fresh plant material. The additive is intended for use with all fresh plant material for all animal species at a proposed minimum concentration of 1 × 108 colony forming units (CFU)/kg fresh plant material. The bacterial species L. coryniformis is considered by EFSA to be suitable for the qualified presumption of safety approach to safety assessment. The identity of the strain was established and no acquired antimicrobial resistance genes of concern were detected. Therefore, the FEEDAP Panel concluded that the use of the strain as a silage additive is considered safe for all the animal species, for consumers of products from animals fed the treated silage and for the environment. Regarding user safety, the additive containing Loigolactobacillus coryniformis DSM 34345 should be considered as a potential skin and respiratory sensitiser, and any exposure through skin and respiratory tract is considered a risk. One preparation was shown not to be irritant to skin or eyes. However, the Panel cannot assess the irritation potential of other possible preparations. The FEEDAP Panel concluded that Loigolactobacillus coryniformis DSM 34345 has the potential to improve the production of silages prepared from all fresh plant materials at a minimum concentration of 1 × 108 CFU/kg fresh material.