Experimental Model For Study Research Articles

Effects of selenium supplementation on glycemic control markers in healthy rodents: A systematic review protocol.

BackgroundIn vivo and in vitro studies have shown that Se has an insulin-mimetic action associated with its antioxidant activity. Other studies, in turn, suggest that high Se doses and high selenoprotein expression interfere with insulin signaling. This study aims to evaluate the effects of Se supplementation on glycemic control markers in healthy rodents.MethodsThe protocol was developed according to the Preferred Reporting Items for Systematic Review and Metaanalysis Protocol (PRISMA-P) and was published in the International Prospective Register of Systematic Reviews database (PROSPERO; CRD4202121201142019119181). Experimental, randomized, or non-randomized studies of healthy rodents models will be included. All forms of supplemented Se will be considered, including organic, inorganic, and synthetic compounds, selenium-enriched yeasts, zerovalent Se nanoparticles, and selenized polysaccharides. Fasting blood glucose will be considered the primary outcome. Homeostatic model assessment, plasma and erythrocyte Se concentration, GPX activity, SELENOP concentration, and other Se biomarkers will be considered secondary outcomes. EMBASE, Scopus, Pubmed/Medline, Web of Science, and CINAHL will be searched for articles published with no language restrictions. Two reviewers will independently conduct the search and selection of articles, data extraction, and quality analysis. The risk of bias and methodological quality analyses of the included studies will be performed using the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) and Collaborative Approach to Meta-Analysis and Review (CAMARADES) tools, respectively. The results will be presented as a narrative synthesis according to the Synthesis Without Meta-analysis (SWiM) Reporting Guideline. Meta-analyses will be conducted where appropriate using random-effects models.DiscussionThe review may clarify the interaction between different forms of supplemented Se and glycemic control in rodents models. The results will provide evidence that will help select doses and forms of Se to administer in clinical trials while according to impact on the glycemic control while elucidating mechanisms of Se metabolism.

A subjective analysis of participants’ views in a study of experimental modelling of imposed airway obstruction in infants and children

Deliberate airway obstruction is a well-recognised form of child abuse and one of the most common causes of death in cases of child homicide. Although classical signs such as petechial haemorrhages can be helpful in raising the suspicion of mechanical asphyxia, they are not always present. Therefore, distinguishing between bruising caused by accidents, medical conditions or non-accidental injury remains challenging. We aimed to characterise bruising patterns which are potentially more consistent with deliberate airway obstruction by means of an experimental modelling study. The first results of our project were previously published and demonstrated that bruising anywhere on the head may be consistent with deliberate upper airway obstruction. In this paper, we present the findings of a questionnaire carried out during the modelling to assess participants’ perception of force and consider how variables such as age, use of adjuncts and force distribution may affect bruising patterns in deliberate airway obstruction. Statistical analysis of our results showed that participants felt they were using less force in scenarios involving the infant rather than the child resuscitation dummy as well as when using adjuncts, meaning marks are likely to be more subtle. Therefore, in such cases it is important to examine for other signs of asphyxiation (such as petechiae) and consider the possibility that adjuncts might have been used which could make picking up localised injuries more difficult. Our results also showed that participants often felt force was not distributed evenly across the digits, reporting the greatest force through either the thumb in isolation or the thumb plus another digit in up to nearly 50% of cases. This suggests that just one or two bruises may be consistent with deliberate airway obstruction.

Magma fragmentation: a perspective on emerging topics and future directions

The breaking apart of magma into fragments is intimately related to the eruptive style and thus the nature and footprint of volcanic hazards. The size and shape distributions of the fragments, in turn, affect the efficiency of heat transfer within pyroclastic plumes and currents and the settling velocity, and so the residence time, of particles in the atmosphere. Fundamental work relating the glass transition to the fragmentation of magmas remains at the heart of conceptual and numerical models of volcanic eruptions. Current fragmentation criteria, however, do not predict the sizes and shapes of the resulting fragments, or fully account for the multiphase nature of magmas or ways in which magma can break in a fluidal manner or by thermal stress. The pulsatory, non-steady state nature of some eruptions, and related interactions with these fragmentation criteria, also requires further investigation. Here, we briefly review some recent advances in the field of magma fragmentation and provide a perspective on how integrated field, experimental and numerical modelling studies can address key outstanding challenges.

BONE REGENERATION IN HEALTHY AND OSTEOPOROTIC CONDITIONS. PRECLINICAL EVIDENCE.

Introduction Osteoporosis is one of the most common skeletal disorders affecting a significant percentage of people worldwide. Research data suggested that systemic diseases such as osteoporosis could act as risk factors for bone regeneration, jeopardizing the healing process and thus the predictability of bone regenerative techniques on compromised patients. The use of titanium dental implants is considered a successful and largely predictable treatment option for partial/full edentulism. However, a prerequisite for the successful implant placement in the prosthodontally ideal driven position is a minimum amount of bone at the recipient site. It is well accepted that preclinical studies in experimental models simulating healthy and systemic conditions, are one of the most important stages in the research of new biomaterials and therapeutic modalities. Aim and Methods The aim of this study is to review the potential effect of osteoporosis on guided bone regeneration in healthy and osteoporotic-like conditions in preclinical models. Material and Methods Literature search was conducted in MEDLINE and PUBMED up to March 2022. Results Research data showed significant new bone apposition in the defect sites, although a trend for less bone formation of lower quality was observed in osteoporotic compared to healthy conditions. Conclusion Evidence suggested that low level of estrogen might negatively affect the biological process of bone grafts/substitutes integration. Preclinical studies provide the possibility of better understanding the underlying mechanism of bone regeneration in compromised conditions. It is important to emphasize that optimization of these models, simulating healthy and systemic conditions, is important for future research.

Effect of Morphologically Transformed Acellular Dermal Matrix on Chronic Diabetic Wounds: An Experimental Study in a Calvarial Bone Exposure Diabetic Rat Model.

The use of acellular dermal matrix on chronic diabetic wounds in clinical practice is hindered by its high cost and difficulty in application. We aimed to acquire experimental evidence on the effect of morphologically transformed acellular dermal matrix on chronic diabetic wounds and investigate how this transformation affects the wound healing mechanism. We developed a new chronic wound model that resembles a diabetic chronic wound as it involves an open wound with partial calvarial bone exposure in diabetic rats. According to treatment materials, rats were assigned into the CONTROL, ADM, and PASTE groups. The wound healing period was subdivided into T1 and T2 (postoperative days 14 and 30, respectively). Three-staged analyses were performed using 3D camera, histological analysis, and real-time quantitative polymerase chain reaction. The morphologically transformed acellular dermal matrix showed a compatible treatment rate in the total wound and more rapidly reduced the initial bone exposure area. In the PASTE group, collagen scaffold appeared at a later period and expression levels of epidermal growth factor and epidermal growth factor receptor increased. The transformation of acellular dermal matrix into the pulverized form is thought to contribute to its non-inferior therapeutic effect compared with normal acellular dermal matrix. With respect to the mechanism, the pulverized form reduced the bone exposure area in the early stage and provided a collagen scaffold at a later period. An increase in epithelial growth factors through mechanochemical transformations along with increased contact area contribute to the enhanced healing capacity of the morphologically transformed acellular dermal matrix.

Prophylactic Effects of NFκB Essential Modulator-Binding Domain Peptides on Bone Infection: An Experimental Study in a Rabbit Model.

IntroductionOsteomyelitis is characterized by intensive inflammatory bone disease and remains a clinical challenge in orthopedic surgery, despite the advances made in medical and surgical therapies. Staphylococcus aureusis a major causative agent of osteomyelitis, causing the progressive inflammatory destruction of bone. Prophylaxis of osteomyelitis during orthopedic surgery is necessary. NFκB essential modulator–binding domain (NBD) peptides are cell-permeable peptide inhibitors of the IκB-kinase complex. The prophylactic effect of NBD peptides in relieving inflammation and inhibiting bone defects in osteomyelitis is still under investigation. Our purpose was to determine the preventive effect of NBD peptides in S. aureus infection–induced bone defects in osteomyelitis.MethodsAn S. aureus osteomyelitis rabbit model was used in this study. The rabbits were divided into four groups: NBD, cefazolin, control, and PBS. Clinical and laboratory indicators of erythrocyte-sedimentation rate, CRP, and TNFα levels were assessed to monitor systemic reactions. The efficacy of NBD peptides in S. aureus–induced osteomyelitis was evaluated by radiological, histological, and microbiological examinations, immunohistochemistry, immunofluorescence, and micro-CT scans.ResultsIn general, NBD peptides effectively reduced clinical signs in rabbits when compared with the control group. Radiography indicated that there was more severe osteomyelitis in the bacterium-infection control group. There was no significance between cefazolin- and NBD-group average scores. The histological results of the lesion slices further confirmed different severity among the groups. Additionally, significant pathological differences were found between the cefazolin and NBD groups, and the PBS group showed no obvious pathological changes.ConclusionProphylactic administration of NBD peptides to bone-defect areas inhibited bacterial spread and promoted bone regeneration, making NBD peptides a possible treatment option for prophylaxis in bone infections.

Optimizing pressure retarded osmosis spacer geometries: An experimental and CFD modeling study

Existing desalination plants face the challenges of high energy costs and environmental impacts from brine disposal. Pressure retarded osmosis (PRO) is a membrane-based technology that could mitigate these issues by capturing the potential energy in the salinity gradient between brine and dilute (e.g., freshwater/wastewater) solutions. Currently, a major challenge facing PRO is concentration polarization (CP), which is the reduction of the salinity gradient caused by the buildup of solutes along both the brine side of the membrane surface (external) and within the membrane support structure (internal). CP can be reduced using membrane spacers, but they have the drawback of increasing the pressure drop along the length of the feed channel. Therefore, it is important to design a membrane spacer that can minimize the effects of both CP and the internal pressure drop. In this study, we simulated the effect that membrane spacer geometries have on CP and the internal pressure drop via computational fluid dynamics (CFD) using the open-source software, OpenFOAM. Simulations were validated using experimental results for five physical spacer geometries on a bench-scale PRO system. The highest performing physical spacer geometry was a 47 mil (1.41 mm) thick parallel oriented spacer (47P), which was then improved upon through integrated CFD-based optimization using the open-source optimization toolkit, DAKOTA. Single-objective genetic algorithms were used to iteratively modify the spacer geometry by increasing the linearity of the thinner cross-strand and decreasing the linearity of the thicker parallel strand, which created a more hexagonally shaped cross-section. This modification was able to increase overall system performance, which was represented by the ratio of the mass flux density of the feed permeate through the membrane to the pressure drop across the length of the feed channel, by 16.3%. This suggests that a membrane spacer with a parallel hexagonal configuration allows the fluid to flow with minimal internal pressure drop while still creating the necessary back-mixing from the membrane surface to the bulk fluid needed to promote mass transfer and reduce the impacts of CP. Implementing these improvements in spacer design would cause the feed pump to consume less energy, which would increase the net energy generation potential and overall sustainability of PRO systems.

SGLT2 Inhibitors as the Most Promising Influencers on the Outcome of Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease (NAFLD), the most frequent liver disease in the Western world, is a common hepatic manifestation of metabolic syndrome (MetS). A specific cure has not yet been identified, and its treatment is currently based on risk factor therapy. Given that the initial accumulation of triglycerides in the liver parenchyma, in the presence of inflammatory processes, mitochondrial dysfunction, lipotoxicity, glucotoxicity, and oxidative stress, can evolve into non-alcoholic steatohepatitis (NASH). The main goal is to identify the factors contributing to this evolution because, once established, untreated NASH can progress through fibrosis to cirrhosis and, ultimately, be complicated by hepatocellular carcinoma (HCC). Several drugs have been tested in clinical trials for use as specific therapy for NAFLD; most of them are molecules used to cure type 2 diabetes mellitus (T2DM), which is one of the main risk factors for NAFLD. Among the most studied is pioglitazone, either alone or in combination with vitamin E, glucagon-like peptide-1 (GLP-1) receptor agonists, dipeptidyl peptidase-4 (DPP-4) inhibitors. Actually, the most promising category seems to be sodium-glucose cotransporter (SGLT2) inhibitors. Their action is carried out by inhibiting glucose reabsorption in the proximal renal tubule, leading to its increased excretion in urine and decreased levels in plasma. Experimental studies in animal models have suggested that SGLT2 inhibitors may have beneficial modulatory effects on NAFLD/NASH, and several trials in patients have proven their beneficial effects on liver enzymes, BMI, blood lipids, blood glucose, and insulin resistance in NAFLD patients, thus creating strong expectations for their possible use in preventing the evolution of liver damage in these patients. We will review the main pathogenetic mechanisms, diagnostic modalities, and recent therapies of NAFLD, with particular attention to the use of SGLT2 inhibitors.

Integrated experimental and thermodynamic modeling study of phase equilibria in the ‘CuO0.5’-MgO-SiO2 system in equilibrium with liquid Cu metal for characterizing refractory-slag interactions

An integrated experimental and thermodynamic modeling study of the phase equilibria in the ‘CuO0.5’-MgO-SiO2 system in equilibrium with liquid Cu metal has been undertaken to better understand the reactions between MgO-based refractories and liquid slag in copper converting and refining processes. New experimental phase equilibria data at 1250–1680 °C were obtained for this system using a high-temperature equilibration of synthetic mixtures with predetermined compositions in silica ampoules or magnesia crucibles, a rapid quenching technique, and electron probe X-ray microanalysis of the equilibrated phase compositions. The system has been shown to contain primary phase fields of cristobalite (SiO2), tridymite (SiO2), pyroxene/protoenstatite (MgSiO3), olivine/forsterite (Mg2SiO4), periclase (MgO), and cuprite (Cu2O). Three regions of 2-liquid immiscibility were found—two in the high-silica range of compositions above the cristobalite primary phase field (close to ‘CuO0.5’-SiO2 and MgO–SiO2 binaries) and one in the low-SiO2, high-‘CuO0.5’ compositional region above the periclase and olivine phase fields. The results obtained in this study indicate that silica in high-copper refining slags likely led to olivine and pyroxene phase formation, increased solubility of MgO in liquid slag, and decline in the performance of MgO-based refractories. New experimental data were used in the development of a thermodynamic database describing this pseudo-ternary system.

In Silico Analysis of the Antagonist Effect of Enoxaparin on the ApoE4-Amyloid-Beta (Aβ) Complex at Different pH Conditions.

Apolipoprotein E4 (ApoE4) is thought to increase the risk of developing Alzheimer’s disease. Several studies have shown that ApoE4-Amyloid (A) interactions can increment amyloid depositions in the brain and that this can be augmented at low pH values. On the other hand, experimental studies in transgenic mouse models have shown that treatment with enoxaparin significantly reduces cortical A levels, as well as decreases the number of activated astrocytes around A plaques. However, the interactions between enoxaparin and the ApoE4-A proteins have been poorly explored. In this work, we combine molecular dynamics simulations, molecular docking, and binding free energy calculations to elucidate the molecular properties of the ApoE4-A interactions and the competitive binding affinity of the enoxaparin on the ApoE4 binding sites. In addition, we investigated the effect of the environmental pH levels on those interactions. Our results showed that under different pH conditions, the closed form of the ApoE4 protein, in which the C-terminal domain folds into the protein, remains stabilized by a network of hydrogen bonds. This closed conformation allowed the generation of six different ApoE4-A interaction sites, which were energetically favorable. Systems at pH5 and 6 showed the highest energetic affinity. The enoxaparin molecule was found to have a strong energetic affinity for ApoE4-interacting sites and thus can neutralize or disrupt ApoE4-A complex formation.

Role of the Antioxidant Activity of Melatonin in Myocardial Ischemia-Reperfusion Injury.

Ischemia-reperfusion injury is a common problem in the age of interventional cardiology; it is primarily mediated by oxidative stress and reactive agents. Melatonin has antioxidative properties that make its use promising for treating ischemia-reperfusion injury. Multiple experimental studies in murine and porcine models have been performed with good results. Clinical trials have also been conducted but given their heterogeneity, no conclusive results can be made. Melatonin pharmacokinetic properties are not ideal; therefore, many analogs have been proposed with improved characteristics, and some studies have evaluated their efficacy in animal models, but clinical trials are needed to recommend their use. In this review, we expose the results of the most impactful studies regarding melatonin use in ischemia-reperfusion injury.

Phase instabilities in austenitic steels during particle bombardment at high and low dose rates

Disruption of phase stability by energetic particle bombardment is a major challenge in designing advanced radiation-tolerant alloys and ion beam processing of nanocomposites. Particularly, ballistic dissolution susceptibility of different solute nanocluster species in alloys is poorly understood. Here, low dose rate neutron irradiations were conducted on a Fe-Cr-Ni based austenitic steel in the BOR-60 reactor (9.4 × 10−7 dpa/s, 318 °C) followed by accelerated dose rate ion irradiations at multiple temperatures (~ 10−3 dpa/s, 380 – 420 °C). Using atom probe tomography, the stability of radiation-enhanced Cu-rich and radiation-induced Ni-Si-Mn-rich nanoclusters was evaluated. During neutron irradiation, Cu-rich clusters nucleated with their core concentrations progressively increasing with dose, while Ni-Si-Mn-rich clusters formed and evolved into G-phase precipitates. Ion irradiations dramatically altered the nanoclusters. Cu-rich clusters were ballistically dissolved, but Ni-Si-Mn-rich clusters remained stable and coarsened with dose at 400 and 420 °C, highlighting that different nanocluster species in a single microstructure can have innately distinct ballistic dissolution susceptibilities. Solute-specific recoil rates were incorporated into the Heinig precipitate stability model, which shows that in addition to radiation-enhanced diffusion, recovery from ballistic dissolution depends on solute concentration gradient near cluster interfaces. The combined experimental-modeling study quantified the critical temperatures and damage rates where ballistic dissolution dominates for each cluster species.

Association of Blastocystis hominis with colorectal cancer: A systematic review of in vitro and in vivo evidences.

BACKGROUNDRecently, there have been several findings that showed intestinal colonisation of Blastocystis hominis (Blastocystis) as a risk factor to the worsening of colorectal cancer (CRC). However, studies have shown controversial results in the pathogenicity of Blastocystis.AIMTo review systematically the evidence available on the association between CRC and Blastocystis and the prevalence of Blastocystis in CRC patients and to investigate cytopathic and immunological effects of Blastocystis in in vitro and in vivo studies.METHODSPRISMA guidelines were utilised in conducting this systematic review. Original articles published before February 2, 2020 were included. PubMed, Science Direct, Scopus and Google scholar databases were searched. Manual searching was carried out to find articles missed during the online search.RESULTSOut of 12 studies selected for this systematic review, seven studies confirmed the prevalence of Blastocystis and found it to be between 2%-28% in CRC patients, whereby subtype 1 and subtype 3 were predominantly seen. A total of four studies employing in vitro human colorectal carcinoma cell line study models showed significant cytopathic and immunological effects of Blastocystis. In addition, one in vivo experimental animal model study showed that there was a significant effect of infection with Blastocystis on exacerbation of colorectal carcinogenesis.CONCLUSION Blastocystis is a commonly identified microorganism in CRC patients. These studies have provided supportive data that Blastocystis could exacerbate existing CRC via alteration in host immune response and increased oxidative damage. Future studies of CRC and Blastocystis should attempt to determine the various stages of CRC that are most likely to be associated with Blastocystis and its relationship with other intestinal bacteria.

Amniotic Fluid: A Perspective on Promising Advances in the Prevention and Treatment of Necrotizing Enterocolitis.

Necrotizing enterocolitis (NEC) is a common and potentially fatal disease that typically affects preterm (PIs) and very low birth weight infants (VLBWIs). Although NEC has been extensively studied, the current therapeutic approaches are unsatisfactory. Due to the similarities in the composition between human amniotic fluid (AF) and human breast milk (BM), which plays a protective role in the development of NEC in PIs and VLBWIs, it has been postulated that AF has similar effects on the outcome of NEC and potential therapeutic implications. AF has been long used for its diagnostic purposes and is often discarded after birth as “biological waste”. However, researchers have started to elucidate its therapeutic potential. Experimental studies in animal models have shown that diseases of various organ systems can possibly benefit from AF-based therapy. Hence, we have identified three approaches which show promising results for future clinical application in the prevention and/or treatment of NEC: (1) administration of processed AF (PAF) isolated from donor mothers, (2) administration of AF stem cells (AFSCs), and (3) administration of simulated AF (SAF) formulated to mimic the composition of physiological AF. We have highlighted the most important aspects that should be taken into account to guide further research on the clinical application of AF-based therapy. We hope that this review can provide a framework to identify the challenges of AF-based therapy and help to design future studies to better evaluate AF-based approaches for the treatment and/or prevention of NEC in PIs and VLBWIs.

Assessment and Comparison of Cable-Actuation of Pill Bug Inspired Adaptive Origami Structure Using Computer Vision and Dynamic Relaxation

The ancient art of origami can be harnessed for the development of adaptive structures, including those at civil-engineering scale. This can be enhanced with biomimetics, the study and development of synthetic mechanisms that mimic the structure or functionality of biological organisms in nature. The origami structure presented in this paper draws inspiration from pill bugs, a species of woodlice that can alter its shape between a flat and a rolled configuration. The panel type origami pill bug structure is modelled as bars, hinges, and active elements for actuation. This paper provides analysis and comparison of a new formulation of the form-finding method called dynamic relaxation for the analytical study with a computer vision algorithm for the experimental study of a 3D-printed model. The objective of this study is to simulate and experimentally validate the quasi-static and dynamic response to characterize the kinematic properties and dynamic behavior of the origami pill bug structure.

The importance of vascular epithelial growth factor (VEGF) and inducible nitric oxide synthase (INOS) in rhinitis medicamentosa pathogenesis: An experimental rat model study.

Our aim in this study is to reveal the expression of Vascular Endothelial Growth Factor (VEGF) and Inducible Nitric Oxide Synthase (iNOS) in the pathogenesis of rhinitis medicamentosa (RM), which occurs as a result of the overdose and long-term use of topical nasal decongestants. In this study, 24 Wistar albino rats were divided into two groups as experimental and control groups. In the experimental group, 50 µl of 0.05% oxymetazoline (iliadin® merck) was applied intranasally to each nostril three times a day for 2 months with the help of a micropipette. 50 µl saline was applied to the control group. At the end of the second month, the rats were examined. RM was detected in the experimental group. Then the nasal tissues of the rats were removed and fixed with 10% phosphate buffered neutral formaldehyde (pH=7.4). Nasal tissues were decalcified in Morse's solution (10% sodium citrate and 22.5% formic acid). Histopathological evaluations of the preparations were stained using Masson Trichrome (TCM) and Hematoxylin Eosin (H&E) techniques and immunohistochemical examinations of the preparations were stained with VEGF and iNOS antibodies and photographed using the Leica DM6000B microscope and the Leica Application Suite Program. In the RM group, we found a significant increase in VEGF and iNOS expression in the nasal mucosa compared to the control group (p<0.001). We also observed the main histopathological changes in the nasal mucosa under a light microscope, including squamous metaplasia in the epithelium of the tunica mucosa, submucosal perivascular edema and degeneration of the submucosal glands. According to these results, increased expression levels of VEGF and iNOS play an important role in rebound swelling in RM pathogenesis.

Bibliometric and Visualized Analysis of Tissue Engineering for Cartilage Repair and Regeneration Over the Past Decade.

Tremendous progress has been made in the field of cartilage repair and regeneration, particularly with tissue-engineering approaches. This study aims to estimate the global status and current trends in the field of cartilage tissue engineering. Publications from 2011 to 2020 on tissue engineering for cartilage repair and regeneration were retrieved from Web of Science Core Collection database. The source data were statistically evaluated based on the bibliometrics. In terms of visualized analysis, some bibliometric indicators such as bibliographic coupling, co-citation, co-authorship and co-occurrence analysis were performed by VOSviewer software, to investigate the research trends in tissue engineering for cartilage repair and regeneration. In total, 3715 papers were included. Since 2011, the amount of issued papers and relative research interest (RRI) have grown by leaps and bounds globally. The United States was the biggest contributor to the research in this field, due to the greatest citation frequency, the highest H index and the strongest total link strength. Romania had the highest average citation for each. The journal Tissue Engineering Part A published most articles in this field. For institutions, the largest contributors were Shanghai Jiaotong University, University of California System and Sichuan University. Studies could all be grouped into four main clusters: study of biomaterial scaffolds, study of seeding cells and growth factors, experimental animal model and clinical study, and mechanism research. Great efforts should be put into the study of biomaterial scaffolds, seeding cells and growth factors, considered to be the next hot topics in cartilage tissue engineering. This findings provide collaborative insights and research orientation for academic researchers, surgeons and healthcare practitioners to a certain extent. The online version contains supplementary material available at 10.1007/s43465-021-00569-1.

Composite-to-metal joining using interference fit micropins

Interference fit micropinning is a novel joining method that involves inserting thin pins with a size interference into an array of ultra-thin holes to create high strength structural joints. An experimental and finite element (FE) modelling study demonstrates the high structural properties of composite-to-metal joints using interference fit micropins. The joint studied consisted of plates of carbon-epoxy laminate and aluminium alloy joined using an array of steel micropins (505 μm diameter) with a close interference (1%) to the holes. The interference fit micropins are effective at creating composite-to-metal joints with high specific ultimate strength and ductility. The capacity of micropins to provide composite-to-metal joints with high structural properties under lap shear and peel load conditions is demonstrated. The effect of the spacing and number of micropins on the joint properties is evaluated.

Genetic Biomarkers of Metabolic Detoxification for Personalized Lifestyle Medicine.

Metabolic detoxification (detox)—or biotransformation—is a physiological function that removes toxic substances from our body. Genetic variability and dietary factors may affect the function of detox enzymes, thus impacting the body’s sensitivity to toxic substances of endogenous and exogenous origin. From a genetic perspective, most of the current knowledge relies on observational studies in humans or experimental models in vivo and in vitro, with very limited proof of causality and clinical value. This review provides health practitioners with a list of single nucleotide polymorphisms (SNPs) located within genes involved in Phase I and Phase II detoxification reactions, for which evidence of clinical utility does exist. We have selected these SNPs based on their association with interindividual variability of detox metabolism in response to certain nutrients in the context of human clinical trials. In order to facilitate clinical interpretation and usage of these SNPs, we provide, for each of them, a strength of evidence score based on recent guidelines for genotype-based dietary advice. We also present the association of these SNPs with functional biomarkers of detox metabolism in a pragmatic clinical trial, the LIFEHOUSE study.

Experimental and kinetic modeling study of the homogeneous chemistry of NH3 and NOx with CH4 at the diluted conditions

Homogeneous oxidation of CH4/NH3/NO/NO2 mixtures in the temperature range from 600 to 1200 K was investigated in this work. Seven gas mixtures were designed to reveal the influence of CH4 and NO/NO2 ratio during the reaction process. The experiments were carried out in a laminar flow reactor at atmospheric pressure. Synchrotron vacuum ultraviolet photoionization mass spectrometry was used to achieve comprehensive detection of major products and critical hydrocarbon, carbonyl and nitrogenous intermediates. An improved kinetic model, which incorporates a detailed C1-C2/NOx/NH3 sub-mechanism was developed to complement the experiments. In general, the experimental results are in good agreement with prediction of the kinetic model. Rate of production analysis and sensitivity analysis were performed to interpret the experimental observations. The results show that in the oxidation of NH3/NOx mixtures, the NO/NO2 ratio can affect the conversion of NO through the reaction NH2 + NO2 = H2NO + NO. In the presence of CH4, the oxidation reactivity of NH3/NOx mixture is significantly promoted. As the added amount of CH4 increases, the production of H2O is enhanced while N2 formation is inhibited. Beside, the addition of CH4 also promotes the production of carbonyl and nitrogenous species. In the oxidation of CH4/NH3/NOx mixtures, the change of NO2/NO ratios only has little effect on the formation of major products and intermediates.