Reproducible Process Research Articles

Nanostructured Ag‐Bioglass Implant Coatings with Antibacterial and Osteogenic Activity

AbstractBone implant failure due to aseptic loosening and biofilm infections is an increasing healthcare problem. Implants may be coated with nanoparticles to avoid bacterial colonization and promote osseointegration. However, these nanocoatings often require long, expensive, and complex manufacturing routes with limited clinical translation potential. Here, a multifunctional nanoparticle coating consisting of silver (Ag) and bioglass (BG) is investigated to overcome current limitations by providing synchronously antibacterial and osteogenic effect. Flame spray pyrolysis (FSP) is exploited as a scalable and reproducible process to synthesize large quantities of nanoparticles and deposit them on titanium (Ti) substrates. The deposited nanocoatings show a homogeneous morphology and biomineralize after soaking in simulated body fluid (SBF), while their adhesion on Ti substrates is promoted by in situ flame annealing. The Ag+ ion release from Ag containing BG samples inhibits Staphylococcus aureus biofilm formation up to 3 log units, while the osteogenic responses of pre‐osteoblastic cells directly grown on AgBG samples show similar levels of alkaline phosphatase activity, calcium and collagen production when compared to pure Ti. The inexpensively synthesized multifunctional AgBG nanostructured implant coatings exert a high bioactivity and antibacterial response while maintaining high biocompatibility. The insights of this study can direct the development of multifunctional implant coatings.

Analysis of issues in gate recess etching in the InAlAs/InGaAs HEMT manufacturing process

AbstractWe have developed an InAlAs/InGaAs metamorphic high electron mobility transistor device fabrication process where the gate length can be tuned within the range of 0.13 μm–0.16 μm to suit the intended application. The core processes are a two‐step electron‐beam lithography process using a three‐layer resist and gate recess etching process using citric acid. An electron‐beam lithography process was developed to fabricate a T‐shaped gate electrode with a fine gate foot and a relatively large gate head. This was realized through the use of three‐layered resist and two‐step electron beam exposure and development. Citric acid‐based gate recess etching is a wet etching, so it is very important to secure etching uniformity and process reproducibility. The device layout was designed by considering the electrochemical reaction involved in recess etching, and a reproducible gate recess etching process was developed by finding optimized etching conditions. Using the developed gate electrode process technology, we were able to successfully manufacture various monolithic microwave integrated circuits, including low noise amplifiers that can be used in the 28 GHz to 94 GHz frequency range.

Characterisation of Fibre Bundle Deformation Behaviour—Test Rig, Results and Conclusions

Deformation of continuous fibre reinforced plastics during thermally-assisted forming or joining processes leads to a change of the initial material structure. The load behaviour of composite parts strongly depends on the resultant material structure. The prediction of this material structure is a challenging task and requires a deep knowledge of the material behaviour above melting temperature and the occurring complex forming phenomena. Through this knowledge, the optimisation of manufacturing parameters for a more efficient and reproducible process can be enabled and are in the focus of many investigations. In the present paper, a simplified pultrusion test rig is developed and presented to investigate the deformation behaviour of a thermoplastic semi-finished fiber product in a forming element. Therefore, different process parameters, like forming element temperature, pulling velocity as well as the forming element geometry, are varied. The deformation behaviour in the forming zone of the thermoplastic preimpregnated continuous glass fibre-reinforced material is investigated by computed tomography and the resultant pulling forces are measured. The results clearly show the correlation between the forming element temperature and the resulting forces due to a change in the viscosity of the thermoplastic matrix and the resulting fiber matrix interaction. In addition, the evaluation of the measurement data shows which forming forces are required to change the shape of the thermoplastic unidirectional material with a rectangular cross-section to a round one.

Strategic partnering to enable cell therapy commercialization: an ArsenalBio case study

As emerging cell therapies move towards the commercialization phase, focus has been placed on establishing scalable and reproducible manufacturing processes and incorporating innovations to streamline cell therapy manufacturing. Strategic partnering between biotech and pharma companies can facilitate the challenging transition of moving cell therapies through the commercialization pipeline.

Denoising of Distributed Acoustic Sensing Seismic Data Using an Integrated Framework

Abstract Distributed acoustic sensing (DAS) is an emerging technology that offers great potential in the high-resolution multi-scale seismic investigation due to its dense spatial coverage and cost-effectiveness. However, DAS data notoriously suffer from the low signal-to-noise ratio (SNR) due to various types of strong noise, for example, high-frequency noise, high-amplitude erratic noise, vertical or horizontal noise. Here, we propose a novel denoising framework by cascading several individual denoising methods that are designed for suppressing specific types of noise. First, to suppress the high-frequency noise, we apply a bandpass filter, which is implemented by recursive infinite impulse response filtering in the time domain. Second, to suppress the erratic noise, we apply a structure-oriented median filter that arises from the reflection seismology field. Finally, to suppress the vertical or horizontal noise, we apply a carefully designed dip filter in the frequency–wavenumber domain. The overall effect of these cascaded denoising steps is that the DAS data can be dramatically improved in terms of SNR. We introduce in detail the implementations of each step in the proposed denoising framework and analyze their respective contribution toward the final improvement. We demonstrate the effectiveness of the proposed denoising framework through the open-access Frontier Observatory for Research in Geothermal Energy (FORGE) geothermal DAS dataset and provide the reproducible processing workflows for all the DAS subsets containing the catalog earthquake and microseismic events.

Investigations on laser beam welding of thick steel plates using a high-power diode laser beam source

For joining of thick steel plates, commonly arc welding and partially laser-arc hybrid welding are used. Both techniques offer individual disadvantages besides their advantages. Arc welding processes are typically characterized by low welding speeds, high heat inputs, high distortions, and high filler material consumptions. Laser-arc hybrid welding processes are limited to weldable material thicknesses regarding weld imperfections as well as the ability to bridge gaps. Therefore, the investigations presented are about high-power diode laser beam welding of steel with plate thicknesses t between 15 and 30 mm using output powers PL of up to 60 kW and welding speeds v between 0.5 and 1.0 m/min. The welding experiments contain butt welds by using weld backing materials. Among other things, influence of energy per unit length (laser beam power PL, welding speed v), focal position z, and plate thickness t are analyzed for different reproducible processes. The evaluation of weld seams includes visual inspection, metallographic analyses regarding geometric characteristics, and weld imperfections as well as radiographic inspections. The investigations show achievable qualities and characteristics of the weld seams depending on the plate thickness t by using high-power diode laser beam sources. Weld seams on plates with thicknesses t of 15 and 22 mm were welded without cracks or other weld imperfections according to metallographic analyses and radiographic testing by using a laser beam power PL of 40 kW and the suitable process parameters developed. As a result, relatively high plate thicknesses t can be welded in a single layer with high quality as well as comparatively high welding speed v.

Database of SARS-CoV-2 and coronaviruses kinetics relevant for assessing persistence in food processing plants

SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2), a virus causing severe acute respiratory disease in humans, emerged in late 2019. This respiratory virus can spread via aerosols, fomites, contaminated hands or surfaces as for other coronaviruses. Studying their persistence under different environmental conditions represents a key step for better understanding the virus transmission. This work aimed to present a reproducible procedure for collecting data of stability and inactivation kinetics from the scientific literature. The aim was to identify data useful for characterizing the persistence of viruses in the food production plants. As a result, a large dataset related to persistence on matrices or in liquid media under different environmental conditions is presented. This procedure, combining bibliographic survey, data digitalization techniques and predictive microbiological modelling, identified 65 research articles providing 455 coronaviruses kinetics. A ranking step as well as a technical validation with a Gage Repeatability & Reproducibility process were performed to check the quality of the kinetics. All data were deposited in public repositories for future uses by other researchers.

Innovative component positioning method for thermoformed electronics

This research presents an innovative method to accurately and repeatedly position electronic components in thermoformed electronics. The paper focuses on 3D shaped electronics, which are made up of stretchable metal structures integrated into thermoformable material. We used the degree of freedom theory to develop a design method that allows us to build the circuit in 2D in such a way that there is only one possible position for electronic components in the final 3D shape after thermoforming the sample. As a result, we have a reproducible design process for thermoformed electronics. We have assessed the result of the fabricated samples by measuring the 3D coordinates of the components on the 3D shaped design using a 3D scanner. The results proved that we have a repeatable component positioning methodology.

Public Policy and Broader Applications for the Use of Text Analytics During Pandemics

The state of Iowa conducted an initial business survey in March 2020 as the novel coronavirus disease 2019 (COVID-19) broke out across the United States. The survey data have been used for decision and policy making at the state level. Relief incentive packages were provided via the Iowa Economic Development Authority (IEDA) to Iowa-based companies to support their operations. A team of policy makers, faculty, and industry professionals was formed to conduct text analyses, analyze the survey responses, validate insights, and ensure that the appropriate policies were enacted. The analysis yielded a reproducible process using the statistical software R to quickly analyze large volumes of free-text responses to open-ended survey questions and develop topics comparable to those found through human coding. This process, using biterm topic models (BTMs), was first used to verify and validate the results of human coding and, because of its increased speed to insights compared with that of human coding, to validate hypotheses empirically much more quickly in subsequent surveys. Analyzing free-text responses has given the IEDA confidence that open-ended survey questions provide value not previously captured. In addition to the original survey, the three subsequent ones, along with several additional projects, have been shaped by the original text-mining methods. History: This paper was refereed. This article has been selected for inclusion in the Special Issue on Analytics Remedies to COVID-19.

Application of Parametric Modeling in Atomic Layer Deposition

Atomic Layer Deposition (ALD) is sequential and conformal process that provides precise thickness control due to its self-limiting nature even in high aspect ratio structures. The exponential growth in the use of ALD is due the availability of hundreds of precursor chemistries for diverse technological applications beyond just semiconductors and microelectronics. However, one of recurring challenges is the problem of results disparity, and errors that underline the causes of disparity, primarily may be due to lack of consistency in process optimization and reproducibility. In this research, a Design of Experiment (DoE) approach is adopted for parametric optimization for synthesis of Al2O3 thin films using ALD. The objective of this work is to adopt DoE for reproducible ALD synthesis processes within statistical reliability.Briefly, the precursors used for Al2O3 ALD (Ultratech Veeco Thermal ALD) were Trimethylaluminum (TMA) and H2O with Ozone. The effect of four parameters, namely pulse duration of TMA and water, number of cycles, and temperature were evaluated for the response parameter of Al2O3 thickness on Si with 300 nm of SiO2. E-Chip DoE software was chosen for data modeling. E-Chip considers multivariate analysis to provide the parametric relationship for Analysis of Variances (ANOVA) and predictive surface response analysis, thus eliminating the need for extensive process optimization experiments that are required for full factorial design. Initially, screening experiments were conducted to determine the levels of input parameters. The pulse duration for TMA and H2O were 0.01-0.02 sec, the number of cycles were varied between 50 and 100, the temperature range was 100-200 0C. For each sample, five thickness and roughness readings were measured on an ex-situ ellipsometer and Atomic Force Microscope (AFM). The stoichiometry of Al2O3 thin films were evaluated using XPS.The data analysis reveals that the influential parameters are number of cycles, pulse duration, and temperature in the order of their significance. The direct relationship between number of cycles and Al2O3 thickness infers that flux available is effectively used for layer growth. The consistency of layer thickness is related not just to the conformality but also to the adsorption of reactive species effectively. Uneven pulse duration also contributes to the linear growth of layer thickness, which supports the effectiveness of reactive species saturation and purging of un-reactive elements. The temperature variation was also an influential parameter as it affected the vapor pressure for TMA and H2O. This mechanistic model based on DoE is a suitable tool to predict the ALD’s growth per cycle, which can further help in understanding of any chemisorption with substrate treatment or variation in film roughness characteristics. Study of other DoE parameters such as type of substrate, substrate functionalization, reactor size in relation to the size of substrate, and purge duration are ongoing. Figure 1 describes the ANOVA chart estimates and surface response graphs, which identifies the bounded parametric region along with the ability to predict the influence of change in parameters based on developed mechanistic model. Figure 1

Evaluating a novel approach to stimulate open science collaborations: a case series of "study-a-thon" events within the OHDSI and European IMI communities.

We introduce and review the concept of a study-a-thon as a catalyst for open science in medicine, utilizing harmonized real world, observation health data, tools, skills, and methods to conduct network studies, generating insights for those wishing to use study-a-thons for future research. A series of historical study-a-thons since 2017 to present were reviewed for thematic insights as to the opportunity to accelerate the research method to conduct studies across therapeutic areas. Review of publications and experience of the authors generated insights to illustrate the conduct of study-a-thons, key learning, and direction for those wishing to conduct future such study-a-thons. A review of six study-a-thons have provided insights into their scientific impact, and 13 areas of insights for those wishing to conduct future study-a-thons. Defining aspects of the study-a-thon method for rapid, collaborative research through network studies reinforce the need to clear scientific rationale, tools, skills, and methods being collaboratively to conduct a focused study. Well-characterized preparatory, execution and postevent phases, coalescing skills, experience, data, clinical input (ensuring representative clinical context to the research query), and well-defined, logical steps in conducting research via the study-a-thon method are critical. A study-a-thon is a focused multiday research event generating reliable evidence on a specific medical topic across different countries and health systems. In a study-a-thon, a multidisciplinary team collaborate to create an accelerated contribution to scientific evidence and clinical practice. It critically accelerates the research process, without inhibiting the quality of the research output and evidence generation, through a reproducible process.

Transfection innovation for large-scale AAV & LV: considerations for process development through commercial manufacturing

GMP-compliant nucleic acid delivery to HEK293 cells is often a critical first step in the manufacture of advanced therapies utilizing recombinant adeno-associated virus (AAV) or lentivirus (LV) to facilitate delivery of a therapeutic transgene to patients. Accordingly, the need for safe and reproducible large-scale viral vector manufacture processes has never been greater. Mirus Bio has developed a fully synthetic, innovative transfection formulation to enable higher titer AAV and LV generation and reduce the cost of therapeutic development and manufacture to bring more life-changing doses to patients sooner. Initial viral vector process development efforts tended towards adherent cell culture and transient transfection. These were for rare indications with low demand, and lower doses were needed. Now, the industry is undergoing rapid manufacturing development to support the upcoming demand for higher prevalence and/or dosage diseases. As a result, the size and yield in manufacturing have increased, as well as the need for lower costs to enable economic manufacture.

Strategic partnering to enable cell therapy commercialization

As emerging cell therapies move towards the commercialization phase, focus has been placed on establishing scalable and reproducible manufacturing processes and incorporating innovations to streamline cell therapy manufacturing. This article will discuss how strategic partnering between biotech and pharma companies can facilitate the challenging transition of moving therapies through the commercialization pipeline.

A 3D Collagen-Based Bioprinted Model to Study Osteosarcoma Invasiveness and Drug Response.

The biological and therapeutic limits of traditional 2D culture models, which only partially mimic the complexity of cancer, have recently emerged. In this study, we used a 3D bioprinting platform to process a collagen-based hydrogel with embedded osteosarcoma (OS) cells. The human OS U-2 OS cell line and its resistant variant (U-2OS/CDDP 1 μg) were considered. The fabrication parameters were optimized to obtain 3D printed constructs with overall morphology and internal microarchitecture that accurately match the theoretical design, in a reproducible and stable process. The biocompatibility of the 3D bioprinting process and the chosen collagen bioink in supporting OS cell viability and metabolism was confirmed through multiple assays at short- (day 3) and long- (day 10) term follow-ups. In addition, we tested how the 3D collagen-based bioink affects the tumor cell invasive capabilities and chemosensitivity to cisplatin (CDDP). Overall, we developed a new 3D culture model of OS cells that is easy to set up, allows reproducible results, and better mirrors malignant features of OS than flat conditions, thus representing a promising tool for drug screening and OS cell biology research.

Impact of microcarrier concentration on mesenchymal stem cell growth and death: Experiments and modeling.

Mesenchymal stem cell (MSC) products are promising therapeutic candidates to treat a wide range of pathologies. The successful commercialization of these cell therapies will, however, depend on the development of reproducible cell production processes. For this, using microcarriers as growth supports within controlled conditions may be a viable process option. Although increasing microcarrier concentration may be associated with greater productivity due to the increased available culture surface, additional friction or shocks between microcarriers are likely to lead to undesired cell death. However, data detailing the impact of microcarrier collisions on MSC growth remains scarce. The following work demonstrates that MSC growth on microcarriers is greatly influenced by particle concentration even when little impact is observed on the apparent growth rate. It is suggested that the apparent growth rate may result in an equilibrium between growth and death kinetics which are independently affected by particle concentration and that certain MSCquality attributes may be progressively degraded in parallel. In addition, the theoretical reduction of theMSC growth rate was modeled according to the ratio between the average interparticle distance and the Kolmogorov scale. This study is an original contribution toward understanding the hydrodynamic effects in microcarrier-based stem cell cultures.

Manufacturing of Peptide Microarrays Based on Catalyst-Free Click Chemistry.

Immobilization of peptides to a solid surface is frequently an important first step before they can be probed with a variety of biological samples in a heterogeneous assay format for research and clinical diagnostic purposes. Peptides can be derivatized in many ways to subsequently covalently attach them to an activated solid surface such as, for instance, epoxy-functionalized glass slides. Here, we describe a clean, efficient, and reproducible fabrication process based on catalyst-free click chemistry compatible with the construction of low- to high-density peptide microarrays.

Reproducible low-cost flexible quadruple-tank process experimental setup for control educators, practitioners, and researchers

The major hurdle in accessing laboratory experimentation is the cost of acquiring experimental scientific equipment, which is unbearable for many institutions. This paper aims to provide the community of control educators, practitioners, and researchers with an open-source low-cost experimental setup and dedicated interface, which is flexible and very easily reproducible. The proposed apparatus is a setup of four interconnected tanks. The setup is representative of real-life industrial processes and it can be adjusted to allow for several configurations for flexibility. A user-friendly dedicated MATLAB/Simulink interface with a personal computer is developed. It supports a seamless shift between a numeric simulation of the quadruple-tank process dynamics and the interface with the physical experimental plant. The CAD models, technical drawings, wiring schematics, PCB design, interface, assembly tutorials, and several examples are provided in an open-source repository. The parts are inexpensive, readily obtained, and fast to assemble. Each setup costs under 650€ and takes roughly 4 h to assemble. In this paper, several application examples are presented, not only for educational purposes, but also for the validation of a state-of-the-art decentralized control method.

Modification of Tubings for Peristaltic Pumping of Biopharmaceutics

Protein particle formation during peristaltic pumping of biopharmaceuticals is due to protein film formation on the inner tubing surface followed by rupture of the film by the roller movement. Protein adsorption can be prevented by addition of surfactants as well as by increasing the hydrophilicity of the inner surface. Attempts based on covalent surface coating were mechanically not stable against the stress of roller movement. We successfully incorporated surface segregating smart polymers based on a polydimethylsiloxane (PDMS) backbone and polyethylene glycol (PEG) side blocks in the tubing wall matrix. For this we applied an easy, reproducible and cost-effective process based on soaking of tubing in toluene containing the PDMS-PEG copolymer. With this tubing modification we could drastically reduce protein particle formation during peristaltic pumping of a monoclonal antibody and human growth hormone (HGH) formulation in silicone and thermoplastic elastomer-based tubing. The modification did not impact the tubing integrity during pumping while hydrophilicity was increased and protein adsorption was prevented. Free PDMS-PEG copolymer might have an additional stabilizing effect, but less than 50 ppm of the PDMS-PEG copolymer leached from the modified tubing during 1 h of pumping in the experimental setup. In summary, we present a new method for the modification of tubings which reduces protein adsorption and particle formation during any operation involving peristaltic pumping, e.g. transfer, filling, or tangential flow filtration.

Synthesis of hierarchically porous Ni foam-supported heazlewoodite Ni3S2 nanorod electrocatalysts for highly efficient oxygen evolution reaction

At present, the design of highly efficient and stable oxygen electrocatalysts for water-splitting cells in alkaline medium is predominantly limited by the sluggish kinetics for the oxygen evolution reaction (OER). This study proposes a facile and reproducible synthesis process to nurture the hierarchically porous Ni3S2 arrays on nickel foam (Ni3S2@NF) for use as a catalyst. For the hydrothermal synthesis reaction, ultrathin nanorod heazlewoodite Ni3S2 catalysts on NF is synthesized by controlling the amount of hydrazine (2 mL) and the processing time/temperatures (150 ℃ for 12 h). Due to the hierarchically porous nanorod morphologies, Ni3S2@NF under O2-saturated 1 M KOH aqueous solution shows excellent OER performance, with a low overpotential of 263 mV at a current density of 100 mA‧cm−2 and a Tafel slope of 72 mV‧dec−1. Further, Ni3S2@NF shows stable potential behavior at around 1.521 V under the constant current operation of 50 mA cm−2 for 50 h. Ni3S2@NF also shows negligible performance degradation during the constant current (at 50 mA cm−2 for 50 h) and voltage cycling (1.25–1.65 V for 1000 cycles) tests in a 1 M KOH solution. The excellent catalytic performance of Ni3S2@NF can be attributed to the hierarchically porous and ultrathin nanorod structures, the multi-valence-state character of Ni element, and the synergistic effect of NF, and high intrinsic catalytic active electrocatalysts for the OER.

In Search of a Universal Method: A Comparative Survey of Bottom-Up Proteomics Sample Preparation Methods.

Robust, efficient, and reproducible protein extraction and sample processing is a key step for bottom-up proteomics analyses. While many sample preparation protocols for mass spectrometry have been described, selecting an appropriate method remains challenging since some protein classes may require specialized solubilization, precipitation, and digestion procedures. Here, we present a comprehensive comparison of the 16 most widely used sample preparation methods, covering in-solution digests, device-based methods, and commercially available kits. We find a remarkably good performance of the majority of the protocols with high reproducibility, little method dependency, and low levels of artifact formation. However, we revealed method-dependent differences in the recovery of specific protein features, which we summarized in a descriptive guide matrix. Our work thereby provides a solid basis for the selection of MS sample preparation strategies for a given proteomics project.