Academic Research Laboratory Research Articles

Cardiac Tissue Engineering as Use Case to Connect Biomedical Research Laboratories to an Emerging Global Data Infrastructure.

Methods for cardiac tissue engineering and application in experiments are core technologies developed at the Institute of Pharmacology and Toxicology in Göttingen. As is the case in many academic research laboratories data capture and documentation may be improved to latest methods of digital research. A comprehensive information system infrastructure is the foundation of further advances toward automation of lab processes. A data management system concept is proposed and prototypically deployed that enables traceability of assets within the lab and reproducibility of published assays and results. The prototype integrates existing electronic lab notebook, experiment result database, and a newly introduced research data management system by means of a custom developed portal and integration component. The architecture concept and developed integration tools explore connection of routine experimental work in a biomedical research lab to a universal infrastructure of data.

Incorporating Specific Functional Strength Integration Techniques to Improve Functional Performance for Veterans After Total Hip Arthroplasty: Protocol for a Randomized Clinical Trial.

Total hip arthroplasty (THA) is a common procedure, yet persistent deficits in functional performance exist after surgery. These deficits may be related to movement compensations observed after THA, which negatively affect quality of life and may increase morbidity and health care utilization, including in the veteran population. However, the best rehabilitative approach to remediating movement compensations and physical function deficits has not been determined. The objective is to determine if a functional strength integration intervention (FSI), as part of a post-THA rehabilitation program, improves movement compensation, physical function, muscle strength, and self-reported outcome measures more than a control group (CON) undergoing a standard of care exercise program. This is a 2-arm randomized, controlled clinical trial. The Veteran Affairs outpatient physical therapy clinics and academic research laboratory will be the settings. One hundred veterans undergoing THA for hip osteoarthritis will be included in the study. Participants will be randomized to either the FSI or CON group and participate in visits of physical therapy over 8weeks. The FSI protocol will include targeted exercise to improve muscular control and stability around the hip and trunk to minimize movement compensation during daily activity combined with progressive resistance exercise. The CON protocol will include patient education, flexibility activity, and low load resistance exercise. Functional performance, muscle strength and endurance, and self-reported outcomes will be measured at baseline (prior to surgery), midway through intervention (6weeks after surgery), at the end of intervention (10weeks after surgery), and 26weeks after THA. The inability to blind treating therapists to study arm allocation is a limitation. The proposed study aims to determine if targeted FSI can affect movement compensation to improve functional outcomes after THA more than traditional rehabilitation paradigms.

Learning how to pivot.

After 5 years as a postdoc and co–principal investigator in an academic research lab, I am about to start my own company. It's a big step, and I'm excited—and a little anxious—about how it will work out. I am very aware that things might not go the way I envision. But pivoting does not feel as intimidating as it could—because I've done it before, starting early in my career. In doing so, I've learned that career changes should not be feared. Instead, they are valuable opportunities for professional development and growth. ![][1] ILLUSTRATION: ROBERT NEUBECKER > “Professors told me that a move to industry would be a path of no return.” When I finished my undergraduate training 14 years ago, I wanted to continue in academic research. But none of my applications for Ph.D. programs was successful. I wondered whether spending time in an industry job might help me stand out. At the same time, I worried that going to industry would compromise my chances of ultimately pursuing an academic career. Colleagues and professors told me that a move to industry would be a path of no return, and that big career changes could be rough. It felt like a momentous decision that would set the tone for the rest of my career. Nonetheless, I decided to take the leap and accept a position at a biotech company. To my surprise, I loved working there. In fact, my experience was so positive that I changed plans. I did not want to do a Ph.D. anymore; I wanted a career in industry. I thought I had found my vocation, and that my path was clear. But my position was just a 1-year contract, and when I started to look for my next industry job, I hit a bureaucratic obstacle. I was searching for jobs across Europe, and in many countries my undergraduate degree was not considered sufficient training for the positions I wanted. So much for that supposedly clear path. It looked like it was time for another pivot—back to where I had started, applying to Ph.D. programs. Again, I wondered whether moving back and forth between industry and academia might put me at a disadvantage with potential future employers. But my previous transition had taught me I should be open-minded and embrace opportunities as they come, even if they are not my top choice at the time. You never know how things are going to turn out. So, I tried not to be too anxious about changing course again. During one interview for a Ph.D. program, the selection committee focused on how uncommon it was for someone working in industry to want to come back to academia. I had played my cards right; I stood out! The program accepted me, and I enjoyed my Ph.D. experience. I loved the science, had a great mentor, and lived in a fantastic city. Even though I had pictured a different course, I didn't have any regrets. When I finished my Ph.D., I still wanted to return to industry. I thought my previous industry experience coupled with my improved credentials would make the transition relatively easy, but that did not end up being the case. I wasn't getting any job offers. I was disappointed, but I took some solace in remembering how well pivoting had worked out for me in the past. I was now much more comfortable moving from plan A to plan B—or even plan C. So, I started to apply for postdoctoral positions. I got a great offer to start an independent line of research in a group with an outstanding working environment, and my time there has been great. In addition to my research, I've developed my entrepreneurial and leadership skills as co-founder and president of my Ph.D. program's alumni association. Looking back, plan B feels like a plan A—just as it did so many times before in my back-and-forth career. And now I'm ready to embark on plan C: setting out as an entrepreneur. I accepted a job in industry when my mind was in academia. I found a job in academia when all I wanted was a job in industry. Yet I feel happy with my career path, and I look forward to the pivots yet to come. [1]: /embed/graphic-1.gif

A Roadmap for Foundational Research on Artificial Intelligence in Medical Imaging: From the 2018 NIH/RSNA/ACR/The Academy Workshop.

Imaging research laboratories are rapidly creating machine learning systems that achieve expert human performance using open-source methods and tools. These artificial intelligence systems are being developed to improve medical image reconstruction, noise reduction, quality assurance, triage, segmentation, computer-aided detection, computer-aided classification, and radiogenomics. In August 2018, a meeting was held in Bethesda, Maryland, at the National Institutes of Health to discuss the current state of the art and knowledge gaps and to develop a roadmap for future research initiatives. Key research priorities include: 1, new image reconstruction methods that efficiently produce images suitable for human interpretation from source data; 2, automated image labeling and annotation methods, including information extraction from the imaging report, electronic phenotyping, and prospective structured image reporting; 3, new machine learning methods for clinical imaging data, such as tailored, pretrained model architectures, and federated machine learning methods; 4, machine learning methods that can explain the advice they provide to human users (so-called explainable artificial intelligence); and 5, validated methods for image de-identification and data sharing to facilitate wide availability of clinical imaging data sets. This research roadmap is intended to identify and prioritize these needs for academic research laboratories, funding agencies, professional societies, and industry.

Ethics as a rare bird: a challenge for situated studies of ethics in the engineering lab

ABSTRACTEngineering ethics cannot be reduced to the ethics of individual engineers but must be considered in situ, within the sociocultural and environmental contexts of a research or design project. We studied teams in academic engineering research laboratories and how they understood and practiced ethics in their own work. Problems arise for ethnographic methods for researching this aspect of engineering ethics; namely, voluntary ethics discussions rarely occurred in the lab. In our field site, we observed many spontaneous discussions, but engineering ethics issues were not among the topics discussed. Ethical decision-making seemed to be like a rare, shy species of bird, hard to spot, requiring methods to flush it out of hiding or attract it. We adapted structured interview and facilitated discussion protocols to accomplish this. Success was modest. The problem lies both in engineering culture and in the methodological difficulties in studying situated, distributed ethical deliberation and responsibility.

The power and accessibility of high-throughput methods for catalysis research

Developing catalytic reactions for organic synthesis is the central goal of countless research groups worldwide. High-throughput experimentation is invaluable for this pursuit, with the requisite tools becoming increasingly available to both industrial and academic research labs.

Adenosine Triphosphate Release is Required for Toll-Like Receptor-Induced Monocyte/Macrophage Activation, Inflammasome Signaling, Interleukin-1β Production, and the Host Immune Response to Infection.

Monocytes and macrophages produce interleukin-1β by inflammasome activation which involves adenosine triphosphate release, pannexin-1 channels, and P2X7 receptors. However, interleukin-1β can also be produced in an inflammasome-independent fashion. Here we studied if this mechanism also involves adenosine triphosphate signaling and how it contributes to inflammasome activation. In vitro studies with human cells and randomized animal experiments. Preclinical academic research laboratory. Wild-type C57BL/6 and pannexin-1 knockout mice, healthy human subjects for cell isolation. Human monocytes and U937 macrophages were treated with different inhibitors to study how purinergic signaling contributes to toll-like receptor-induced cell activation and interleukin-1β production. Wild-type and pannexin-1 knockout mice were subjected to cecal ligation and puncture to study the role of purinergic signaling in interleukin-1β production and host immune defense. Toll-like receptor agonists triggered mitochondrial adenosine triphosphate production and adenosine triphosphate release within seconds. Inhibition of mitochondria, adenosine triphosphate release, or P2 receptors blocked p38 mitogen-activated protein kinase and caspase-1 activation and interleukin-1β secretion. Mice lacking pannexin-1 failed to activate monocytes, to produce interleukin-1β, and to effectively clear bacteria following cecal ligation and puncture. Purinergic signaling has two separate roles in monocyte/macrophage activation, namely to facilitate the initial detection of danger signals via toll-like receptors and subsequently to regulate nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 3 inflammasome activation. Further dissection of these mechanisms may reveal novel therapeutic targets for immunomodulation in critical care patients.

Metabolic imaging with the use of fluorescence lifetime imaging microscopy (FLIM) accurately detects mitochondrial dysfunction in mouse oocytes

To determine whether metabolic imaging with the use of fluorescence lifetime imaging microscopy (FLIM) identifies metabolic differences between normal oocytes and those with metabolic dysfunction. Experimental study. Academic research laboratories. None. Oocytes from mice with global knockout of Clpp (caseinolytic peptidase P; n = 52) were compared with wild-type (WT) oocytes (n = 55) as a model of severe oocyte dysfunction. Oocytes from old mice (1year old; n = 29) were compared with oocytes from young mice (12weeks old; n = 35) as a model of mild oocyte dysfunction. FLIM was used to measure the naturally occurring nicotinamide adenine dinucleotide dehydrogenase (NADH) and flavin adenine dinucleotide (FAD) autofluorescence in individual oocytes. Eight metabolic parameters were obtained from each measurement (4 per fluorophore): short (τ1) and long (τ2) fluorescence lifetime, fluorescence intensity (I), and fraction of the molecule engaged with enzyme (F). Reactive oxygen species (ROS) levels and blastocyst development rates were measured to assess illumination safety. In Clpp-knockout oocytes compared with WT, FAD τ1 and τ2 were longer and I was higher, NADH τ2 was longer, and F was lower. In old oocytes compared with young ones, FAD τ1 was longer and I was lower, NADH τ1 and τ2 were shorter, and I and F were lower. FLIM did not affect ROS levels or blastocyst development rates. FLIM parameters exhibit strong differentiation between Clpp-knockout versus WT, and old versus young oocytes. FLIM could potentially be used as a noninvasive tool to assess mitochondrial function in oocytes.

Occupational Safety in Academic Research Laboratories: Identifying Upstream Risk Factors

Occupational Safety in Academic Research Laboratories: Identifying Upstream Risk Factors

Theoretical Approaches to Studying Psychological Ensuring of Personnel Management in Scientific Organizations

Introduction. The paper addresses the issue of psychological ensuring of personnel management in Russian scientific organizations. For the first time, the types of scientific organizations in the Russian Federation are analyzed to account for their opportunities and limitations of employing existing international techniques for personnel management under the conditions of growing globalization and informatization in the field of research activities.
 Theoretical Basis. When choosing a theoretical approach for psychological ensuring of personnel management, it is important to take into consideration the type of scientific organization in terms of its research activities (theoretical/applied), form of financing (budget/commercial/mixed), and the place the research activities occupy among a researcher’s professional responsibilities (central/peripheral).
 Results. The study reviewed the following theories and theoretical models: the model of the peaks of a scientist’s creative productivity (G. J. Feist), the model of gift economy in the field of research activities (K. Vermeir), and various hybrid models. According to the study analyses, the concept of motivation for scientific activity (T. V. Razina) can be instrumental in assessing the role of ten types of motivational subsystems when carrying out research activities and developing the means of stimulating them. The study concentrates on the following theoretical models for establishing creative environments: (a) the dynamic theory of organizational knowledge creation (I. Nonaka and colleagues) that is applicable for any organization and (b) the model of creative environments for the research process in academic circles or commercial research laboratories suggested by A. P. Wierzbicki and Y. Nakamori. The paper also analyses certain characteristics of virtual organizations that determine specific aspects of personnel management process and reflects on particular models for its implementation.
 Discussion. The theories and theoretical approaches to managing research teams, encompassed in the study were analyzed specifically in application to scientific organizations in Russia. The main obstacles for their ‘direct’ use there lie in ethnic, national, and specific cultural characteristics of Russian research facilities, limited use of information technology, and the lack of socio-economic and political stability in the country.
 Highlights
 
 Cultural and historical specificity, as well as the vast variety of types of scientific organizations in Russia, determine the need for the development and considerable modification of the existing methods and techniques for personnel management.
 Gradually establishing creative environments in Russian research teams that would take into their specific characteristics has a great potential for the practice of personnel management.
 Carrying out empirical studies on creative productivity – its peaks and the factors that determine them (e.g., age, academic degree) is important for psychological ensuring of personnel management in Russian scientific organizations.

Functional cargo delivery into mouse and human fibroblasts using a versatile microfluidic device

Efficient intracellular cargo delivery is a key hurdle for the translation of many emerging stem cell and cellular reprogramming therapies. Recently, a microfluidic-based device constructed from silicon was shown to transduce macromolecules into cells via shear-induced formation of plasma membrane pores. However, the scalability and widespread application of the current platform is limited since physical deformation-mediated delivery must be optimized for each therapeutic application. Therefore, we sought to create a low-cost, versatile device that could facilitate rapid prototyping and application-specific optimization in most academic research labs. Here we describe the design and implementation of a microfluidic device constructed from Polydimethylsiloxane (PDMS) that we call Cyto-PDMS (Cytoplasmic PDMS-based Delivery and Modification System). Using a systematic Cyto-PDMS workflow, we demonstrate intracellular cargo delivery with minimal effects on cellular viability. We identify specific flow rates at which a wide range of cargo sizes (1-70kDa) can be delivered to the cell interior. As a proof-of-principle for the biological utility of Cyto-PDMS, we show (i) F-actin labeling in live human fibroblasts and (ii) intracellular delivery of recombinant Cre protein with appropriate genomic recombination in recipient fibroblasts. Taken together, our results demonstrate that Cyto-PDMS can deliver small-molecules to the cytoplasm and biologically active cargo to the nucleus without major effects on viability. We anticipate that the cost and versatility of PDMS can be leveraged to optimize delivery to a broad array of possible cell types and thus expand the potential impact of cellular therapies.

Characteristics of Nasal Septal Cartilage-Derived Progenitor Cells during Prolonged Cultivation.

Objective To produce alternate cell sources for tissue regeneration, human nasal septal cartilage-derived progenitor cells (NSPs) were tested to identify whether these cells meet the criteria of cartilage progenitor cells. We also evaluated the effects of prolonged cultivation on the characteristics of NSPs. Study Design In vitro study. Setting Academic research laboratory. Methods NSPs were isolated from discarded human nasal septal cartilage. NSPs were cultured for 10 passages. The expression of septal progenitor cell surface markers was assessed by fluorescence-activated cell sorting. Cell proliferation was measured with a cell-counting kit. Cytokine secretion was analyzed with multiplex immunoassays. Chondrogenic differentiation of NSPs without differentiation induction was analyzed with type II collagen immunohistochemistry. Cartilage-specific protein expression was evaluated by Western blotting. Under osteo- and adipodifferentiation media, 2 lineage differentiation potentials were evaluated by histology and gene expression analysis. Results Surface epitope analysis revealed that NSPs are positive for mesenchymal stem cells markers and negative for hematopoietic cell markers. Cultured NSPs showed sufficient cell expansion and chondrogenic potential, as demonstrated by immunostaining and expression of cartilage-specific protein. IL-6, IL-8, and transforming growth factor ß were secreted by over 200 pg/mL. The osteo- and adipodifferentiation potentials of NSPs were identified by histology and specific gene expression. The aforementioned characteristics were not influenced by prolonged cultivation. Conclusion NSPs represent an initial step toward creating a cell source from surgically discarded tissue that may prove useful in cartilage regeneration.

7th National Conference on Processing and Characterization of Materials (NCPCM 2017)

PREFACEThe 7th National Conference on Processing and Characterization of Materials (NCPCM 2017) was organized by the Department of Metallurgical and Materials Engineering, National Institute of Technology Rourkela, India during 08-09 December 2017.The advanced processing of materials and their subsequent characterization are now-a-days gaining attention owing to the advancement of technology and need of high-quality materials for critical applications. The purpose of the conference was to bring recent developments in materials processing and characterization in the Indian context. About 120 participants and delegates from various organizations in India attended the conference. There were eight technical sessions of about 83 contributory talks along with seven keynote lectures. The conference became a platform for the interaction and exchange of ideas among the scientists, practicing engineers and young researchers from various academic institutions, research laboratories and industries from all over India engaged in frontiers of processing and characterization of conventional as well as advanced materials. This volume contains the selected full-length technical papers presented at the conference NCPCM 2017.

Discovery of Novel Adenosine Receptor Antagonists through a Combined Structure- and Ligand-Based Approach Followed by Molecular Dynamics Investigation of Ligand Binding Mode.

An intense effort is made by pharmaceutical and academic research laboratories to identify and develop selective antagonists for each adenosine receptor (AR) subtype as potential clinical candidates for "soft" treatment of various diseases. Crystal structures of subtypes A2A and A1ARs offer exciting opportunities for structure-based drug design. In the first part of the present work, Maybridge HitFinder library of 14400 compounds was utilized to apply a combination of structure-based against the crystal structure of A2AAR and ligand-based methodologies. The docking poses were rescored by CHARMM energy minimization and calculation of the desolvation energy using Poisson-Boltzmann equation electrostatics. Out of the eight selected and tested compounds, five were found positive hits (63% success). Although the project was initially focused on targeting A2AAR, the identified antagonists exhibited low micromolar or micromolar affinity against A2A/A3, ARs, or A3AR, respectively. Based on these results, 19 compounds characterized by novel chemotypes were purchased and tested. Sixteen of them were identified as AR antagonists with affinity toward combinations of the AR family isoforms (A2A/A3, A1/A3, A1/A2A/A3, and A3). The second part of this work involves the performance of hundreds of molecular dynamics (MD) simulations of complexes between the ARs and a total of 27 ligands to resolve the binding interactions of the active compounds, which were not achieved by docking calculations alone. This computational work allowed the prediction of stable and unstable complexes which agree with the experimental results of potent and inactive compounds, respectively. Of particular interest is that the 2-amino-thiophene-3-carboxamides, 3-acylamino-5-aryl-thiophene-2-carboxamides, and carbonyloxycarboximidamide derivatives were found to be selective and possess a micromolar to low micromolar affinity for the A3 receptor.

Effects of Common Ear Drops on Tympanic Membrane Healing in Rats.

Objective Ciprofloxacin + dexamethasone ear drops have been associated with higher rates of tympanic membrane perforations than ofloxacin. This was thought to be an effect of the steroid; however, ciprofloxacin (sans steroid) has been found to be more toxic to tympanic membrane fibroblasts than ofloxacin in vitro. This study aimed to compare the effect of these agents on tympanic membrane healing in vivo. Study Design Controlled animal study. Setting Academic research laboratory. Methods Perforations were created in 54 rats with a carbon dioxide laser. Rats were randomized to 6 groups (9/group), with 1 ear receiving ofloxacin, ciprofloxacin, dexamethasone, ofloxacin + dexamethasone, ciprofloxacin + dexamethasone, or neomycin, and the contralateral ear receiving saline twice daily for 10 days. Healing was assessed over 40 days. Results Ofloxacin did not delay healing relative to saline. All other treatments delayed healing relative to ofloxacin at day 10 ( P < .0001). Dexamethasone and ofloxacin + dexamethasone delayed healing up to day 14 ( P < .0001). Neomycin and ciprofloxacin + dexamethasone further delayed healing up to day 28 ( P = .009) and day 35 ( P = .043), respectively. All eardrums healed by day 10 with ofloxacin, day 20 with ciprofloxacin, day 28 for dexamethasone, and day 35 for ofloxacin + dexamethasone. At day 40, 2 of 9 ciprofloxacin + dexamethasone-treated eardrums had not healed. All saline-treated eardrums in the ofloxacin, ciprofloxacin, dexamethasone, and ofloxacin + dexamethasone groups were healed by day 14, but this was delayed to day 20 in the ciprofloxacin + dexamethasone group ( P = .007). Conclusions Ototopical quinolones delay rat tympanic membrane healing in a drug-specific manner, with ciprofloxacin having a greater impact than ofloxacin. This effect is potentiated by steroids.

Integration of Antibody Array Technology into Drug Discovery and Development.

Antibody arrays represent a high-throughput technique that enables the parallel detection of multiple proteins with minimal sample volume requirements. In recent years, antibody arrays have been widely used to identify new biomarkers for disease diagnosis or prognosis. Moreover, many academic research laboratories and commercial biotechnology companies are starting to apply antibody arrays in the field of drug discovery. In this review, some technical aspects of antibody array development and the various platforms currently available will be addressed; however, the main focus will be on the discussion of antibody array technologies and their applications in drug discovery. Aspects of the drug discovery process, including target identification, mechanisms of drug resistance, molecular mechanisms of drug action, drug side effects, and the application in clinical trials and in managing patient care, which have been investigated using antibody arrays in recent literature will be examined and the relevance of this technology in progressing this process will be discussed. Protein profiling with antibody array technology, in addition to other applications, has emerged as a successful, novel approach for drug discovery because of the well-known importance of proteins in cell events and disease development.

Photolithography-Based Nanopatterning Using Re-entrant Photoresist Profile.

Photolithography based on optical mask is widely used in academic research laboratories due to its low cost, simple mechanism, and ability to pattern in micron-sized features on a wafer-scale area. Because the resolution is bound by diffraction limits of the light source, nanoscale patterning using photolithography requires short-wavelength light source combined with sophisticated optical elements, adding complexity and cost. In this paper, a novel method of subwavelength patterning process using conventional i-line mercury lamp is introduced, without the use of such advanced optical tools. The method utilizes the re-entrant geometry of image reversal photoresist produced from the developing process, where a secondary mask is generated by isotropically depositing a metal layer to cover the re-entrant profile of the photoresist. Removing the photoresist by applying ultrasonic vibrations in acetone bath uniformly cracks the metal layer at the sidewalls of the re-entrant profile, exposing the substrate with a reduced feature size. The width of the initial mask pattern can be reduced by 400 nm in a controlled manner, regardless of the original width choice. As a result, the method is shown to achieve sub-100 nm scale linear patterns compatible for both subsequent deposition process and dry-etching process. Our approach is applicable to various shapes of the patterns and can be used in electronic device fabrication requiring nanoscale lithography patterning, such as the gate fabrication of AlGaN/GaN high-electron-mobility transistor.

Genome Engineering of Hybridomas to Generate Stable Cell Lines for Antibody Expression.

From the perspective of academic and small research laboratories, the most common and practical strategy for recombinant expression of full-length monoclonal antibodies is to perform transient plasmid transfection of mammalian cells, resulting in small-scale and limited protein production. The generation of stable antibody producing mammalian cell lines enables larger-scale and consistent expression, however this approach is rarely pursued due to the time-consuming and expensive process of single colony screening and characterization. In order to bridge the gap between the simplicity of transient transfection and consistent production by stable cell lines, we describe a method to stably integrate antibody genes into the endogenous immunogenomic loci of hybridoma cells using CRISPR/Cas9 genome editing. Initially, the antibody variable light (VL) chain is deleted by multiplexed Cas9 cleavage; subsequently, the variable heavy (VH) chain is replaced by a fluorescent reporter gene (mRuby) by Cas9-assisted homology-directed repair (HDR). This cell line is customized by replacing mRuby with a synthetic antibody (consisting of a VL, light constant region and VH) by once again using Cas9-assisted HDR. Due to hybridomas' inherent ability to surface display and secrete antibodies, they provide a suitable host for both the selection and the production process, substantially streamlining the process for stable cell line generation, and thus we refer to this platform as plug-and-(dis)play (PnP) hybridomas.

Temperature Augmented Visual Method for Initial Screening of Hydrate Inhibitors

The formation of gas hydrates in oil &amp; gas pipelines and drilling fluid flow lines is a major issue in the petroleum industry. Gas hydrate inhibitors are normally used to inhibit the formation of gas hydrates in the pipelines/flowlines. Initial screening of hydrate inhibitors and AntiAgglomerants (AA) requires a safe and economical experimental setup/method. Conventional visual method was used for initial screening of hydrate inhibitors in many researches. Some researchers also suggested modified visual methods, but all of them lacks accurate measurement of induction time and found to be inappropriate for experimental solutions like drilling mud, etc. In this work, a temperature augmented visual method was presented which can be used in academic research laboratories for study and initial screening of hydrate inhibitors. This method is capable of parallel screening of inhibitors and determines hydrate induction time precisely. Experiments were conducted to determine the hydrate induction time of different inhibitors using augmented method and compared with conventional visual method. The developed method found to be more precise in determining the induction time of hydrates in all types of experimental solutions.

Fabrication of whole-thermoplastic normally closed microvalve, micro check valve, and micropump

There is a critical need to develop fabrication methods for rapid and cost-effective prototyping of thermoplastics-based microfluidics in academic research laboratories. This paper presents a method for the fabrication of whole-thermoplastic microfluidic functional elements, including a pneumatic (gas-actuated) normally closed microvalve, a micro-check valve, and a pneumatic dual-phase micropump. All devices were made from thermoplastic polyurethane (TPU) and poly(methyl methacrylate) (PMMA). The fabrication process consisted of only laser micromachining and thermal fusion bonding without need to perform any particular chemical treatment or use a master mold. These features enable the widespread adaptation of this method in academic research settings. Characterizations revealed that the fabricated normally closed microvalve could stop liquid flows at pressures lower than 2 psi in its passive operation mode where no pressure was used for valve actuation. The check valve could block liquid flows with liquid pressures of up to 30 psi in its reverse mode of operation while it could allow liquid to pass through in its forward mode. In addition, the micropump, which consisted of two check valves and a pneumatic uni-diaphragm displacement chamber, could pump liquid at an average flow rate of 87.6 ± 5.0 μL/min using an actuation frequency and pressure of 1 Hz and ±5 psi, respectively. Taken together, the developed low-cost whole-thermoplastic microfluidic functional elements could be employed for the fabrication of various lab-on-a-chip applications.