Dimensional Resolution Research Articles

Transformer-based adaptive 3D residual CNN with sparse representation for PAN-sharpening of multispectral images

ABSTRACT Panchromatic (PAN)-sharpening is an important process for most of the practical appliances in the domain of geospatial analysis. Because of the balance among instantaneous field of view and Signal-to-Noise Ratio (SNR), the Multi-Spectral (MS) and PAN images with complementary features are captured by the satellite sensors. Fusing PAN illustrations with maximal dimensional resolution and MS illustrations with maximal spectral resolution is known as PAN-sharpening, which is widely utilized to improve spatial and spectral resolutions. The crucial point in the PAN-sharpening task is to maintain a balance between the extraction of data and the insertion of data. If a misbalance occurs, it may lead to a distortion of the intensity. To address these issues, a new PAN-sharpening model is developed to combine the MS and PAN illustrations to increase the image’s spatial resolution. In addition, the spatial and spectral distortions of the illustrations are highly decreased by using this PAN-sharpening model. Originally, the PAN and MS illustrations were collected from traditional online sources. The MS and PAN images are initially combined and given to the sparse representation process. This provides a simulated PAN-sharpened image. This image is further provided to the intelligent deep learning network, which is the Transformer-based Adaptive 3D Residual Convolutional Neural Network (TA-3DRCNN) and hence the higher-resolution images are obtained, and it is useful in various applications. The parameters present in TA-3DRCNN are tuned using the Modified Uniform Number-based Gannet Optimization Algorithm (MUN-GOA) for upgrading the effectiveness of PAN-sharpening. The resultant outcome is contrasted with the customary PAN-sharpening approaches to validate the system’s effectiveness with respect to various measures.

Regulating emulsion properties through tannin acid-mediated gelatin/cellulose nanocrystal complexes: From low-oil emulsion to high internal phase emulsion gel for 3D printing

In this study, a stabilized low-oil emulsion and high internal phase emulsion gels (HIPE gels) integrated preparation method is proposed. Highly stable low-oil emulsions, prepared using tight ternary complexes formed by incorporating tannic acid (TA) into gelatin/cellulose nanocrystals (GLT/CNC) complexes mainly through strengthening hydrogen-bonding interaction. The subsequent heating-centrifugation process was used to enable the conversion of GLT/CNC/TA stabilized low-oil emulsions to stabilized HIPE gels, and systematically investigated the regulation of emulsion properties by TA concentrations. The ternary complexes formed by appropriate concentration of TA (0.6 %) can form stable low-oil emulsions with smallest average particle (36.1 ± 0.25 μm) size and best rheological properties, while the rheological properties of HIPE gels were similarly regulated by the TA concentration (0 %, 0.2 %, 0.6 %, 1.0 %, 1.2 %). Heating induced flocculation of low-oil emulsions without causing demulsification, allowed for the subsequent centrifugation to yield stable HIPE gels, significantly superior to the GLT/CNC/TA-stabilized HIPE gels prepared by conventional methods that typically exhibit thermal instability. TA effectively promoted the interfacial adsorption of GLT/CNC and tight stacking of oil droplets to build a more stable network structure in the continuous phase. HIPE gels with 0.6 % TA demonstrated excellent 3D printability with optimal dimensional resolution and surface quality, presenting a novel strategy for HIPE gel preparation and versatile emulsion applications.

Exploring three-dimensional photoinhibition to enhance vat photopolymerization: A preliminary study

Vat photopolymerization (VPP) based additive manufacturing (AM) technologies print 3D components by using light to selectively cure photosensitive resins. In VPP-based AM, one outstanding challenge remains in controlling the over-curing, which is mainly caused by the diffusive and/or excessive photo-induced species such as free radicals and can severely affect the geometric properties of as-printed parts. Common practices rely on formulating proper resins or optimizing exposure parameters to address the vertical over-curing but often ignore the lateral over-curing. In this work, we develop a new VPP process of photoinhibition aided photopolymer AM (PinPAM) to comprehensively address over-curing issues in both vertical and lateral dimensions for enhancing the properties of as-printed geometry. The PinPAM method incorporates an adaptive photoinhibition zone, generated both surrounding and underneath the curing zone on a layer basis. This differs from current literature approaches that utilize photoinhibition to create a higher deadzone to increase print speed or constrain vertical profiles for achieving volumetric VPP AM. We present several preliminary experimental study cases involving pillar array sample printing. By comparing part dimensions and shapes resulting from traditional VPP and PinPAM, our experiments prove the concept of PinPAM and demonstrate its potential to address over-curing in VPP. Furthermore, we present an initial case study on optimizing the PinPAM process for printing cylinder samples with targeted dimensions, illustrating the planning and implementation of PinPAM. A discussion on future research directions to establish PinPAM is included. The developed PinPAM opens up a new avenue for improving VPP printed parts’ geometrical properties and facilitating its adoption in precision fabrications that demand dimensional accuracy and resolution.

Enhanced optical bistability of energy saving viologen-based electrochromic display with a commercial phenol-based epoxy resin

A highly bistable viologen-based electrochromic display was successfully developed by using a simple strategy with cheap commercial phenol-based epoxy. By adding epoxy, phenol species can contribute a dual effect, in which they can play as electron shuttles to facilitate fast coloration of ECDs and stabilize the long bistability of ECDs through the proton-coupled electron transfer (PCET) mechanism during coloration state. With the use of epoxy, CPHEV2+/E exhibits an improvement of maximum ΔT, which is 78.6 % at 596 nm compared to 53 % for that of ECD without epoxy. The ECD with added epoxy can hold the colored state up to 50 h after applying a voltage of −2.5 V for 15 s compared with ECD without epoxy which is 22 min. Notably, the color state undergoes decomposition to 10 % of its initial value after 3.5 h without any extra power supply. The 3D-printed rose flower ECD was successfully demonstrated using digital light processing (DLP) with good dimensional accuracy and resolution.

Fabrication of telechelic DNA-bridged food emulsion gel as edible ink for 3D printing

Abstract Objectives Interdroplet interactions affect the properties and textures of emulsions. In this study, we creatively introduced telechelic DNA to link oil droplets directly at molecular scale to further improve the viscoelastic properties of emulsions. Materials and Methods A stable emulsion with 70% oil fraction was prepared by adding 40 mg/mL of whey protein isolate and peach gum polysaccharide complex (WPI–PGP complex). The addition of telechelic DNA (0.125–0.375 μmol/L) made the emulsion change from a cream-like state to a self-supporting gel. Results Rheological experiments confirmed that the telechelic DNA could improve the yield stress, storage modulus/loss modulus (Gʹ/Gʹʹ) and apparent viscosity of the emulsion gel in a concentration-dependent manner (0–0.375 μmol/L). Inverted fluorescence images clearly showed the interdroplet network of the emulsion gel linked by telechelic DNA. For 3D printing, the emulsion gel with a higher concentration (0.375 μmol/L) of telechelic DNA displayed better surface quality and dimensional resolution, indicating improved printability. Conclusion This study successfully designed a novel telechelic DNA-bridged emulsion gel, which showed great potential as edible ink for 3D printing.

Preparation and characteristics of honeycomb mullite ceramics with controllable structure by stereolithography 3D printing and in-situ synthesis

Porous honeycomb mullite ceramics were controllably fabricated in-situ using stereolithography 3D printing. The effects of the dispersant type and content on the rheological behavior of the mullite precursor slurry were investigated. Additionally, the influence of the debinding atmosphere (air and argon) on the quality of the samples and formation of cracks was also studied. The results indicated that oleic acid (OA), 3-glycidoxypropylthrimethoxysilane (KH560), and disperbyk (BYK111) displayed the capability to create low-viscosity and highly stable slurries. Among these KH560 was proved to be the most effective. The mullite precursor slurry containing 4 wt% KH560 dispersants exhibited a shear thinning behavior. It displayed a viscosity of 0.26 Pa·s at a shear rate of 30 s−1. The mullite ceramic parts displayed good a dimensional resolution at an exposure dose of 5.47 mJ/cm2. During the debinding process, the printed parts were susceptible to cracking and deformation in air, but remained devoid of defects in argon. When the samples were sintered at 1600 °C, the corundum phase transformed almost completely into the mullite phase. The linear shrinkage values were 5.81%, 6.33%, and 10.26% in the O-X, O–Y and O-Z directions, respectively.

Utility of Cone-Beam Computed Tomography in the Detection of Low Bone Mass-A Systematic Review.

Cone-beam computed tomography (CBCT) is widely used in the preoperative qualitative and quantitative assessment of dental implant sites, offering dimensional accuracy, spatial resolution, gray density, and contrast comparable to those of classical CT scan, yet with disputable ability to determine bone mass density. A systematic review of the literature was performed using the PubMed and SCOPUS databases, with terms referring to low bone mass and cone-beam computed tomography (CBCT). Sixteen studies were included in the review. The results show different perspectives, but the evidence favors the use of CBCT, combined with dual-energy X-ray absorptiometry bone density scan (DXA) evaluation, for the assessment of the osteoporosis status of the aging population and, more specifically, in postmenopausal women. Radiographic density (RD) values of the dens and the left part of the first cervical vertebra show the strongest correlation coefficients and the highest sensitivity, specificity, and accuracy for predicting osteoporosis (OP) in the lumbar vertebrae and the femoral neck. Our review suggests the potential of CBCT as a screening tool for patients with low bone mass using different radiomorphometric indices. Linear measurements of the inferior mandibular cortex were lower in osteoporotic individuals, indicating the perspective of CBCT also as a diagnostic tool for this disease.

P-Band UAV-SAR 4D Imaging: A Multi-Master Differential SAR Tomography Approach

Due to its rapid deployment, high-flexibility, and high-accuracy advantages, the unmanned-aerial-vehicle (UAV)-based differential synthetic aperture radar (SAR) tomography (D-TomoSAR) technique presents an attractive approach for urban risk monitoring. With its sufficiently long spatial and temporal baselines, it offers elevation and velocity resolution beyond the dimensions of range and azimuth, enabling four-dimensional (4D) SAR imaging. In the case of P-band UAV-SAR, a long spatial-temporal baseline is necessary to achieve high enough elevation-velocity dimensional resolution. Although P-band UAV-SAR maintains temporal coherence, it still faces two issues due to the extended spatial baseline, i.e., low spatial coherence and high sidelobes. To tackle these problems, we introduce a multi-master (MM) D-TomoSAR approach, contributing three main points. Firstly, the traditional D-TomoSAR signal model is extended to a MM one, which improves the average coherence coefficient and the number of baselines (NOB) as well as suppresses sidelobes. Secondly, a baseline distribution optimization processing is proposed to equalize the spatial–temporal baseline distribution, achieve more uniform spectrum samplings, and reduce sidelobes. Thirdly, a clustering-based outlier elimination method is employed to ensure 4D imaging quality. The proposed method is effectively validated through computer simulation and P-band UAV-SAR experiment.

Recent Advances on 3D-Printed Zirconia-Based Dental Materials: A Review

Zirconia-based materials are widely used in dentistry due to their biocompatibility and suitable mechanical and tribological behavior. Although commonly processed by subtractive manufacturing (SM), alternative techniques are being explored to reduce material waste, energy consumption and production time. 3D printing has received increasing interest for this purpose. This systematic review intends to gather information on the state of the art of additive manufacturing (AM) of zirconia-based materials for dental applications. As far as the authors know, this is the first time that a comparative analysis of these materials' properties has been performed. It was performed following the PRISMA guidelines and using PubMed, Scopus and Web of Science databases to select studies that met the defined criteria without restrictions on publication year. Stereolithography (SLA) and digital light processing (DLP) were the techniques most focused on in the literature and the ones that led to most promising outcomes. However, other techniques, such as robocasting (RC) and material jetting (MJ), have also led to good results. In all cases, the main concerns are centered on dimensional accuracy, resolution, and insufficient mechanical strength of the pieces. Despite the struggles inherent to the different 3D printing techniques, the commitment to adapt materials, procedures and workflows to these digital technologies is remarkable. Overall, the research on this topic can be seen as a disruptive technological progress with a wide range of application possibilities.

Fabrication of Complex Three-Dimensional Structures of Mica through Digital Light Processing-Based Additive Manufacturing

Mica is a group of clay minerals that are frequently used to fabricate electrical and thermal insulators and as adsorbents for the treatment of cationic pollutants. However, conventional subtractive manufacturing has the drawback of poor three-dimensional (3D) shape control, which limits its application. In this study, we propose digital light processing (DLP)-based additive manufacturing (AM) as one of the most effective ways to address this drawback. Two major challenges for the ceramic DLP process are the production of a homogeneous and stable slurry with the required rheological properties and the maintenance of printing precision. The mica green body was fabricated using a 53 vol.% solid loading slurry through DLP, which exhibited good dimensional resolution under an exposure energy dose of 10 mJ/cm2. The precise, complex 3D structure was maintained without any defects after debinding and sintering at 1000 °C. The use of ceramic AM to overcome the shape-control limitations of mica demonstrated in this study offers great potential for expanding the applications of mica.

Characterisation of irradiated and non-irradiated silicon sensors with a table-top two photon absorption TCT system

A tabletop Two Photon Absorption-Transient Current Technique (TPA-TCT) set-up built at CERN was used to investigate a non-irradiated PIN diode, an irradiated PIN diode, and a non-irradiated 5 × 5-multipad HPK LGAD. The intrinsic three dimensional spatial resolution of this method is demonstrated under normal incidence of the laser probe. A charge collection versus depth profile of the non-irradiated PIN diode is presented, where reflection on the rear silicon-air interface was observed. It is found that the time-over-threshold versus depth profile is particularly suitable to determine the boundaries of the DUT’s active volume. A depth scan of the irradiated PIN diode is discussed and a method to omit the single photon absorption background is presented. Finally, a charge collection measurement in the inter-pad region of the 5 × 5-multipad HPK LGAD is presented and it is demonstrated that TPA-TCT can be used to image the implantation and the electric field of segmented silicon devices in a three dimensional manner.

A novel UV-curable acryl-polyurethane for flexural 3D printing architectures

An acryl-functionalized urethane prepolymer series with various compositions were synthesized using polyethylene glycol (PEG) and hexamethylene diisocyanate (HDI). A novel acryl-urethane resin (AU) was designed by the addition of 2-hydroxyethyl methacrylate (2-HEMA) as a suitable material for digital light processing (DLP) 3D printing. The optimizing photo-initiator and additive were selected by UV-spectroscopy. The formulation containing the UV-curable AU resin and photo-curable additives was exposed to 405 nm UV radiation to produce the flexible 3D architectures. The effects of the photo-initiator/multifunctional acrylate value and UV absorptive power on the 3D printing performance were evaluated in terms of the mechanical properties and dimensional resolution. When the acryl-urethane resin/base acrylate ratio was 1/9, the UV-cured APU formulations had the excellent mechanical properties and highest resolution. The surface properties of the 3D architectures were tuned by controlling the photo-initiator type and composition in the AU resin. Overall, this novel UV-curable AU resin can be a promising prepolymer for the DLP printing of flexible photo-resin for biocompatible and photo-curable applications. © 2001 Elsevier Science. All rights reserved

Abstract GS1-00: Single-cell spatial analysis by imaging mass cytometry and immunotherapy response in triple-negative breast cancer (TNBC) in the NeoTRIPaPDL1 trial

Abstract Background Immunecheckpoint inhibitors are effective in early and advanced TNBC, however only aminority of patients benefit making precision immune-oncology a major unmetneed. Imaging mass cytometry (IMC) enables high dimensional tissue imaging atsubcellular resolution for assessment of TNBC ecosystems, providing informationon cell type composition, functional status, and spatial organisation. Methods InNeoTRIP patients with TNBC were randomized to eight cycles ofnab-paclitaxel/carbo (CT) with/without atezolizumab (CTA). Forty-four proteinsspanning cancer cells and the tumor microenvironment (TME) were assessed onpre-treatment biopsies (n=243/280; 86.8% evaluable after QC). FFPE samples werelabelled with antibodies conjugated to isotopically pure rare earth metalreporters and profiled at one micron resolution by IMC. For each sample, wehave generated three high dimensional images that encompass the tumor,tumor-stroma interface and adjacent stroma. We investigated the association ofprotein expression assessed separately for epithelial and TME cells, cellphenotypes, and spatial architectures with PD-L1 status (Ventana SP142),stromal TILs, TNBC types and pathological complete response (pCR). 237 patients(84.6%) have both IMC and RNA-seq available allowing for comparison with genesignatures derived from HALLMARK,ConsensusTME immune cell types, and Nanostring. Results Across243 samples we identify just over one million single cells. By supervised clustering,we defined 37 robust cell phenotypes. PD-L1-positive tumors, high stromal TILsand TNBC type were characterized by extreme heterogeneity and unique cell-type andspatial TME composition. Severalbiomarkers demonstrated a significant test for interaction. Considering proteinexpression, GATA3 and CD20 on TME, HLA-DR in epithelial cells and Ki67 assessedboth in epithelial and TME, had a significant test for interaction (p <0.05). For all these biomarkers, high expression (above median) was associatedwith an increase of pCR of >10% in favour of atezolizumab, whereas lowerexpression group demonstrated a similar pCR rate among arms.Two cellphenotypes, PD-L1+IDO+ antigen presenting cells (APCs) and CD56+ neuroendocrine(NE) epithelial cells, had a significant test for interaction. Higherexpression of these biomarkers was associated with higher likelihood of pCR in CTAarm, but not in CT arm. For example, PD-L1+IDO+APCs in the CTA arm wereassociated with pCR proportions of 64.6% and 24.6% for above- and below-mediangroups respectively (OR4.5 [2.01-10.1], p<0.001).Mostof these tests of interaction retained significance after adjustment by PD-L1status and stromal TILs. Notably, none among 61 gene-expression basedimmune-related pathways and 7 proliferation-related signatures demonstrated a significant test ofinteraction. Resultsof systematic multi-tiered image analysis at the levels of cell-cellinteractions and recurrent higher order multicellular complexes defining TNBC ecosystemsidentified by graph-based methods will be presented at the meeting. Conclusions Imaging mass cytometry provides a morecomprehensive overview of TNBC heterogeneity at a single-cell level withspatial resolution. Bulk protein or gene expression might deliver limitedpredictive information because it does not consider the cell compartment ofexpression. Precise cell phenotyping highlights the predictive role ofPD-L1+IDO+APCs and CD56+NE epithelial cells. Overall, we demonstrated that IMCis feasible in a large, randomized trial and provides independent predictiveinformation on immune checkpoint inhibitors benefit to PD-L1, TILs and gene-expressionprofiles. Citation Format: Giampaolo Bianchini, Xiao Qian Wang, Esther Danenberg, Chiun-Sheng Huang, Daniel Egle, Maurizio Callari, Begoña Bermejo, Claudio Zamagni, Marc Thill, Anton Anton, Matteo Dugo, Stefania Zambelli, Stefania Russo, Eva Maria Ciruelos, Richard Greil, Vladimir Semiglazov, Marco Colleoni, Catherine Kelly, Gabriella Mariani, Lucia Del Mastro, Balázs Győrffy, Olivia Biasi, Pinuccia Valagussa, Giuseppe Viale, Luca Gianni, H Raza Ali. Single-cell spatial analysis by imaging mass cytometry and immunotherapy response in triple-negative breast cancer (TNBC) in the NeoTRIPaPDL1 trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr GS1-00.

Feasibility of manufacturing of Al2O3–Mo HTCC by hybrid additive process

Additive manufacturing processes make it possible to produce increasingly complex 3D parts. In addition, these numerical processes can be usefully used to manufacture ceramic/metal parts of high dimensional resolution with thermal, electrical and electronic properties of interest for applications in the field of power electronics.In this context, a hybrid additive machine was developed to manufacture ceramic/metal parts. This machine consists in the combination of two additive manufacturing processes: stereolithography and robocasting.Using this hybrid process, the feasibility of HTCC components has been demonstrated by building dielectric alumina by stereolithography and molybdenum conductive network by robocasting. Molybdenum-based metallic formulation adapted to the process and allowing to obtain a high conductive metallic network has been developed. The co-debinding and co-sintering cycles have been optimized to minimize the content of residual carbon and to prevent the oxidation of molybdenum. The alumina/molybdenum interface has also been observed to conclude about a possible delamination between these two materials with different thermal expansion coefficients (CTE). Sintered HTCC parts have been characterized in the domain of hyperfrequency. The frequency responses deviate from the simulation due to a lack of dimensional accuracy of the metallic network.

Middle-up quantification of therapeutic monoclonal antibodies in human plasma with two dimensional liquid chromatography high resolution mass spectrometry: Adalimumab as a proof of principle

Next generation human therapeutic monoclonal antibodies (t-mAbs) are harder to quantify with the widely used bottom-up tryptic digestion method. Due to their homology with endogenous immunoglobulins, there is a lack of unique and stable ‘signature’ peptides that can be targeted. Middle-up two dimensional liquid chromatography high resolution mass spectrometry (2D-LC-HRMS), targeting the entire light chain, was examined as an alternative. Adalimumab (ADM) was successfully quantified in human plasma after Melon® Gel sample purification, followed by orthogonal separation on a weak cation exchange (WCX) and reversed phase column. Charge and hydrophobicity were used to separate ADM from the polyclonal immunoglobulin background. HRMS with its high resolution and exact mass was able to isotopically resolve the ADM light chain and to provide another separation dimension on the basis of mass to charge ratio. Using the targeted single ion monitoring (T-SIM) with multiplex (MSX) option, three ADM light chain precursors, 2341.80, 2129.00, and 1951.68 m/z, and one internal standard precursor 2146.39 m/z, were measured simultaneously. The Melon® Gel sample purification was found to be very efficient in removing plasma proteins that would otherwise interfere with chromatographic separation and ionization. The linearity of the method for the analysis of ADM was excellent (R2=0.999) between 1 – 128 mg/L with an LLOQ signal to noise ratio (S/N) of 10. Within-run and between-run precision and accuracy were in concordance with the EMA guideline. Cross-validation of the 2D-LC-HRM method with the standard peptide LC-MS/MS method showed a good agreement (R2 = 0.86) between the methods. However, there was a bias present, possibly due to charge variant ADM formation over time. Since the presented 2D-LC-HRMS method is able to measure only the native form of ADM, it is able to provide a measure of the active form of ADM in patients.

Post-processing and printability evaluation of red ginseng snacks for three-dimensional (3D) printing

The effect of the types of starch matrix and post-processing conditions on the physical properties of three-dimensional (3D) printed functional snacks were studied. Three types of starch (waxy corn, tapioca and potato) solutions were used at three concentration (7, 10 and 13%) by dissolving in deionized water, while red ginseng powder was fixed at 20% w/w. The use of different types of starch greatly influenced the rheological properties and printability. The highest shear modulus (range of 4.23–9.46 kPa) was measured using high amylose potato starch (PS). The best dimensional stability and printing resolution were obtained with 10% PS. The mechanical properties of the final products after freeze-drying as a post-processing technique were independent of the rheological properties and printability of the red ginseng paste. The hardness of the ginseng snacks showed a relative hardness between pastries (hardness of 20.1 N) and dark chocolate (hardness of 546 N). The results suggested that lyophilization-based post-processing may be a promising tool for modification of the food texture with 3D printing.

Position sensitive measurement of trace lithium in the brain with NIK (neutron-induced coincidence method) in suicide

Mood disorder is the leading intrinsic risk factor for suicidal ideation. Questioning any potency of mood-stabilizers, the monovalent cation lithium still holds the throne in medical psychiatric treatment. Furthermore, lithium`s anti-aggressive and suicide-preventive capacity in clinical practice is well established. But little is still known about trace lithium distribution and any associated metabolic effects in the human body. We applied a new technique (neutron-induced coincidence method “NIK”) utilizing the 6Li(n,α)3H reaction for the position sensitive, 3D spatially resolved detection of lithium traces in post-mortem human brain tissue in suicide versus control. NIK allowed, for the first time in lithium research, to collect a three dimensional high resolution map of the regional trace lithium content in the non lithium-medicated human brain. The results show an anisotropic distribution of lithium, thus indicating a homeostatic regulation under physiological conditions as a remarkable link to essentiality. In contrast to suicide we could empirically prove significantly higher endogenous lithium concentrations in white compared to gray matter as a general trend in non-suicidal individuals and lower lithium concentrations in emotion-modulating regions in suicide.

Bridging the gap between lab-scale and commercial dimensions of hollow fiber nanofiltration membranes

The development of nanofiltration membranes with hollow fiber geometry is a relatively young field of research in membrane science with only limited, but quickly growing, availability on a commercial scale. These membranes offer promising properties for application in water treatment such as high fouling resistance and low cost compared to Reverse Osmosis membranes. Major differences are found in dimension and operating conditions of hollow fiber nanofiltration membranes used in academia and on an industrial scale. To allow for adequate comparison and prediction of membrane performance, the effect of fiber dimension and operating conditions on process performance needs to be properly understood. A systematic experimental study on MgSO4 retention by hollow fiber nanofiltration membranes was performed to investigate the effect of fiber length and operational conditions on membrane performance. A significant drop in the retention of MgSO4 was observed for 1.5 m long fibers in flux ranges of 20 LMH when reducing crossflow velocity to 0.1 m/s. Transport models were used to describe and predict this behavior. We show that the commonly used mass transport models under predict this decrease in retention. Using different theoretical transport models for the hollow fiber feed phase and reducing dimensional resolution from 2D to 1D and 0D allows for the identification of limitations of the commonly applied analytical mass transfer correlations. To accommodate for this discrepancy found between experimental results and model predictions, a correction factor was derived using the 2D model to specifically account for deviations of these correlations at high permeate recovery values. Our newly developed model makes it possible to accurately predict full scale membrane performance solely based on measured done on small scale membranes, an important precondition for the further development of dense hollow fiber based membranes and processes.

A new view of observed galaxies through 3D modelling and visualisation

Observational astronomers survey the sky in great detail to gain a better understanding of many types of astronomical phenomena. In particular, the formation and evolution of galaxies, including our own, is a wide field of research. Three dimensional (spatial 3D) scientific visualisation is typically limited to simulated galaxies, due to the inherently two dimensional spatial resolution of Earth-based observations. However, with appropriate means of reconstruction, such visualisation can also be used to bring out the inherent 3D structure that exists in 2D observations of known galaxies, providing new views of these galaxies and visually illustrating the spatial relationships within galaxy groups that are not obvious in 2D. We present a novel approach to reconstruct and visualise 3D representations of nearby galaxies based on observational data using the scientific visualisation software Splotch. We apply our approach to a case study of the nearby barred spiral galaxy known as M83, presenting a new perspective of the M83 local group and highlighting the similarities between our reconstructed views of M83 and other known galaxies of similar inclinations.

Hybridization of additive manufacturing processes to build ceramic/metal parts: Example of HTCC

Stereolithography is an additive manufacturing process, which makes it possible to fabricate useful complex 3D ceramic parts with a high dimensional resolution, a good surface roughness and properties close to those obtained by classical routes. Previous work concerning LTCC components, demonstrates that it is possible, by coupling the stereolithography with robocasting additive processes, to obtain multi-material components (e.g. ceramic / metal components). On the base of this previous work, the manufacturing of HTCC components using this innovative hybrid additive manufacturing process is described. Various complex and innovative geometries of HTCC alumina/tungsten components, in order to improve the characteristics of current circuits, are built and the mechanical and electrical properties characterized. Finally, hyper-frequency parameters of simulated HTCC complex micro strip resonators were compared to measured values on components manufactured by additive manufacturing.