Collections in this community

Recent Submissions

  • RNA-seq analysis revealed key genes associated with seed germination of Fritillaria taipaiensis P.Y.Li by cold stratification

    Yang, Qiu-Xiong; Chen, Dan; Zhao, Yan; Zhang, Xiao-Yu; Zhao, Min; Peng, Rui; Sun, Nian-Xi; Baldwin, Timothy; Yang, Sheng-Chao; Liang, Yan-Li; et al. (Frontiers Media S.A., 2022-09-28)
    Seed dormancy is an adaptive strategy for environmental evolution. However, the molecular mechanism of the breaking of seed dormancy at cold temperatures is still unclear, and the genetic regulation of germination initiated by exposure to cold temperature requires further investigation. In the initial phase of the current study, the seed coat characteristics and embryo development of Fritillaria taipaiensis P.Y.Li at different temperatures (0°C, 4°C, 10°C & 25°C) was recorded. The results obtained demonstrated that embryo elongation and the dormancy-breaking was most significantly affected at 4°C. Subsequently, transcriptome analyses of seeds in different states of dormancy, at two stratification temperatures (4°C and 25°C) was performed, combined with weighted gene coexpression network analysis (WGCNA) and metabolomics, to explore the transcriptional regulation of seed germination in F. taipaiensis at the two selected stratification temperatures. The results showed that stratification at the colder temperature (4°C) induced an up-regulation of gene expression involved in gibberellic acid (GA) and auxin biosynthesis and the down-regulation of genes related to the abscisic acid (ABA) biosynthetic pathway. Thereby promoting embryo development and the stimulation of seed germination. Collectively, these data constitute a significant advance in our understanding of the role of cold temperatures in the regulation of seed germination in F. taipaiensis and also provide valuable transcriptomic data for seed dormancy for other non-model plant species.
  • More time for aliens? Performance shifts lead to increased activity time budgets propelling invasion success

    Ginal, Philipp; Kruger, Natasha; Wagener, Carla; Araspin, Laurie; Mokhatla, Mohlamatsane; Secondi, Jean; Herrel, Anthony; Measey, John; Rödder, Dennis (Springer, 2022-09-22)
    In the Grinnellian niche concept, the realized niche and potential distribution is characterized as an interplay among the fundamental niche, biotic interactions and geographic accessibility. Climate is one of the main drivers for this concept and is essential to predict a taxon’s distribution. Mechanistic approaches can be useful tools, which use fitness-related aspects like locomotor performance and critical thermal limits to predict the potential distribution of an organism. These mechanistic approaches allow the inclusion key ecological processes like local adaptation and can account for thermal performance traits of different life-history stages. The African Clawed Frog, Xenopus laevis, is a highly invasive species occurring on five continents. The French population is of special interest due to an ongoing expansion for 40 years and a broad base of knowledge. We hypothesize that (1) the French population exhibits increased activity time in the invasive European range that could be devoted to fitness-relevant activity and (2) tadpoles may have less activity time available than adult frogs from the same range. We investigate how thermal performance traits translate into activity time budgets and how local adaptation and differences in the thermal responses of life-history stages may boost the European Xenopus invasion. We use a mechanistic approach based on generalized additive mixed models, where thermal performance curves were used to predict the hours of activity and to compare the potential activity time budgets for two life-history stages of native and invasive populations. Our results show that adult French frogs have more activity time available in Europe compared to South African frogs, which might be an advantage in searching for prey or escaping from predators. However, French tadpoles do not have more activity time in Europe compared to the native South African populations suggesting that tadpoles do not suffer the same strong selective pressure as adult frogs.
  • Modeling of CO2 absorption into 4-diethylamino-2-butanol solution in a membrane contactor under wetting or non-wetting conditions

    Yuan, Cuiting; Li, Linlin; Li, Yifu; Pan, Zhen; Zhang, Na; N.Borhani, Tohid; Zhang, Zhien (Elsevier, 2022-09-14)
    In this work, 4-diethylamino-2-butanol (DEAB) as a new type of alkanolamine solvent is used for CO2 capture in a hollow fiber membrane contactor (HFMC). A model describing the gas and liquid reactions and transport inside the membrane contactor under the wetting or non-wetting conditions was built. The countercurrent flow of natural gas and solvent was considered in the model. To investigate the influence of solvent type on decarburization efficiency, DEAB was used and compared with other common solvents such as potassium carbonate (K2CO3), triethylamine (TEA) and diethanolamine (DEA). Under the same operating conditions, the impact of parameters such as humidity, gas flow rate, liquid concentration, membrane length on the decarburization performance was examined. The results indicate that DEAB solvent has the best overall performance especially under the wetting conditions. It was noted that increasing liquid concentration, membrane length and decreasing gas flow rate enhance decarburization.
  • Do job advertisements promote gender inequality in the construction sector?

    Aluko, Ralph O.; Oshodi, Olalekan; Daniel, Emmanuel Itodo (Unpublished, 2022-08-31)
    The poor performance of construction projects remains a topical issue in the academic field of construction management. Across the globe, statistical data indicates that the construction sector is male dominated. The observed inequality is linked to conflicts, which is one of the main reasons for the poor performance of construction projects. The current study aims to explore the differences between job adverts for male [construction manager] and female [social worker] dominated sectors of the economy by comparing word usage. Text mining was used to unearth the differences in the content of the job advertisements for these two roles. The findings indicate that masculine words [such as leader] are the most commonly used words in the job adverts for construction manager roles. The findings suggest that the content of job adverts seem to promote gender stereotypes associated with employment in the construction sector. Such gender cues may contribute to the gender differences in the construction workforce. Taken together, these findings suggest that there is a need to embed gender-neutral words in job adverts placed by construction sector.
  • Evaluating floating photovoltaics (FPVs) potential in providing clean energy and supporting agricultural growth in Vietnam

    M Pouran, Hamid; Padilha Campos Lopes, Mariana; Ziar, Hesan; Castelo Branco, David; Sheng, Yong (Elsevier, 2022-09-29)
    Vietnam’s promising economic growth has led to energy shortage, growing coal imports, and increasing carbon emissions. The country’s electricity demand annual growth rate has been 12% in recent years and is projected to be 8-9% by 2030. In Vietnam 40% of the land is dedicated to agriculture and thousands of inland water bodies are used for agriculture/aquaculture. Utilising even a small portion of them for Floating Photovoltaics (FPVs) would mitigate land-use conflicts and benefits agriculture and aquaculture. To demonstrate FPVs' potential, we selected a hydropower dam reservoir in the North and six irrigation reservoirs in the South. System Advisor Model (SAM) software was used to simulate the electricity generated if we cover 1%, 5%, and 10% of surfaces of these reservoirs. The results show a potential capacity close to 1 GWp and annual potential generation of 1.4 TWh if 1% of these surfaces were covered by FPVs. We also evaluated FPVs potential for four different types of water bodies in Vietnam: Lake, Lagoon, River and Without Classification. The results showed that the potential capacity, considering use of only of 1% of these water surfaces for FPVs is 3.7 GWp, and provides 5385 GWh generation, which highlights the significant contribution that FPVs can make to the renewable energy sector in this country. However, FPVs face some socio-technical barriers, including regulatory ambiguity about water rights, uncertainty about economic policies and limited information about their environmental impacts that could hamper the expansion of this technology, and need to be addressed through further research.
  • Environmental and technical impacts of floating photovoltaic plants (FPVs) as an emerging clean energy technology

    M Pouran, Hamid; Padilha Campos Lopes, Mariana; Nogueira, Tainan; Castelo Branco, David; Sheng, Yong (Cell Press, 2022-12-31)
    Floating photovoltaic plants (FPVs) are emerging as a new modality of photovoltaic system application. FPVs present several benefits in comparison with ground-mounted systems and could have major and lasting positive environmental and technical impacts globally, which is the focus of this paper. Floating solar technology does not occupy habitable and productive areas and can be deployed in brownfields and degraded environments, that helps reducing land-use conflicts. Saving water through mitigating evaporation and improving water security in water-scarce regions combined with their flexibility for deployment on different water bodies including drinking water reservoirs are of other advantages of FPVs. They also have higher efficiency than ground-mounted PV solar and are compatible with the existing hydropower infrastructures, which supports diversifying the energy supply and its resilience. Despite the notable growth of floating photovoltaics on an international scale, lack of supporting policies and development roadmaps by the governments could hinder FPVs’ sustainable growth. Long-term reliability of the floating structures is also of the existing concerns that if not answered could limit the expansion of this emerging technology.
  • Development of a new bio-microscope for 3D geometry characterization of fruit single cells

    Zhang, Meishuan; Wang, Yiheng; Wang, Junyi; Li, Zhiguo; Tchuenbou-Magaia, Fideline Laure (Wiley, 2022-09-16)
    Fruit cells are living irregular 3D transparent objects which makes them challenging to determine their real 3D size and shape through only two-dimensional (2D) images using the existing biological microscope. This study deals with a newly self-developed biological microscope including a microscope imaging system, a light source system, a stage and a support base for the 3D size characterization of fruit single cells. The main design concept is based on two optical path systems set up at the front (x-axis) and bottom (z-axis) directions of a transparent chamber containing single cells that allow the front view and bottom view of the single cell to be observed. Performance indicators such as mass, size, observation range, objective magnification, total magnification, focal range, focal accuracy and resolution of the developed biological microscope were estimated. Finally, the 3D geometry size of single tomato cells was measured by the new biological microscope to demonstrate the relative ease at which accurate real 3D geometry information of single fruit cells could be obtained, which echoes its scientific value.
  • Renewable energy re-distribution via multiscale IoT for 6G-oriented green highway management

    Rahman, Md Arafatur; Mukta, Marufa Yasmin; Asyhari, A. Taufiq; Moustafa, Nour; Patwary, Mohammad; Yousuf, Abu; Razzak, Imran; Gupta, Brij (IEEE, 2022-09-16)
    While recent works on investigating renewable energy sources for powering the highway offer promising solutions for sustainable environments, they are often impeded by unequal distribution of sources across the region due to variations in solar exposure and road intensity that electromagnetically and mechanically generate the energy. By exploiting viable gathering of massive renewable energy data using the Internet of Things (IoT), this paper proposes a framework for improved highway-energy management based on the unmanned aerial vehicle-assisted wireless energy re-distribution of the harvested renewable energy. Combining both massive low-rate sensing with high-speed 6G-envisioned transmission for data aggregation, the IoT architecture is of multi-scale, consisting of: i) global data exchange and analytics for energy mapping, re-distribution planning and forecasting, and ii) local data sensing and processing at individual highway lampposts for micro-energy management. The feasibility of the networked energy system is analyzed via analytical cost-reliability analyses. The cost analysis demonstrates the cost-effectiveness through the lowest Requirement of Energy and Cost of Energy for the setup and maintenance. The reliability analysis reveals the energy plus (E + ) feature of the system in certain conditions with enhanced reliability in adverse weathers that impact energy generation. With multi-scale data connectivity to intelligently manage standalone renewable energy, this work puts forward a viable idea of 6G use cases with massively networked energy sensors with a vision of achieving super-connected and intelligence-equipped highways.
  • A systematic method for identifying references to academic research in grey literature

    Bickley, Matthew; Kousha, Kayvan; Thelwall, Mike (Springer, 2022-06-23)
    Grey literature encompasses documents not published in academic journals or books. Some grey literature has substantial societal importance, such as medical guidelines, government analyses and pressure group reports. Academic research cited in such documents may therefore have had indirect societal impact, such as in policy making, clinical practice or legislation. Identifying citations to academic research from grey literature may therefore help assess its societal impacts. This is difficult, however, due to the variety of document and referencing formats used in grey literature, even from a single organisation. In response, this study introduces and tests a semi-automatic method to match academic journal articles with unstandardised grey literature cited references. For this, the metadata (lead author last name, title, year) of 2.45 million UK Russell Group university outputs was matched against a 100-document sample of UK government grey literature to assess the accuracy of 21 matching heuristics. The optimal method (lead author last name and title in either order, maximum of 200 characters apart) is sufficiently accurate and scalable to make the task of matching research outputs to grey literature references feasible. The method was then applied to 3347 government publications, showing approximately 23% of UK government grey literature in this study contained at least one reference to UK Russell Group university output, and of this grey literature, an average of 3.79 references were present per document. The applied method also shows that economics and environmental science academic research is most cited between 2010 and 2018.
  • The impact of SARS-CoV-2 variants on IBD management

    Segal, Jonathan P; Kumar, Aditi; Raine, Tim; Lamb, Christopher A; Brookes, Matthew; Department of Gastroenterology and Hepatology, Hillingdon Hospital, Uxbridge UB8 3NN, UK. Electronic address: jonathansegal1@nhs.net. (Elsevier, 2021-03-09)
  • Enhancing the resilience of road networks to flooding

    Xu, Wenping; Zhang, Yuan; Proverbs, David; Zhong, Zhi (Emerald, 2022-07-19)
    Purpose: This paper aims to clarify the resistance degree of group road logistics to flood disaster resilience. The paper measures the resilience of group road logistics by establishing network structure model. The purpose of this study is to improve the resilience of road log. Design/methodology/approach: This paper adopts Delphi method to collect data, interviews mainly flood management experts and supply chain risk management experts, and then analyzes the data through the network structure model combined with interpretative structure model (ISM) and analytical network process (ANP). Findings: The results show that flood frequency and drainage systems are the main factors affecting the resilience of road transport logistics in urban areas. These research results provide useful guidance for the effective planning and design of urban road construction and infrastructure. Research limitations/implications: However, the main factors affecting the resilience of road transport logistics are likely to change with the development of factors such as climate, economy and environment. Therefore, in future work, the authors' research will focus on the further application of this evaluation method. Practical implications: The results show that the impact of flooding on the four dimensions of road logistics resilience varies. This shows that in deciding what intervention measures are to be taken to improve the resilience of the road network to flooding, various measures need to be considered. Social implications: This paper provides a more scientific analysis of the risk management ability of the road network in the face of floods. In addition, it also provides a useful reference for urban road planners. Originality/value: This paper addresses a clear need to study how to build models to improve the resilience of road logistics in flood risk.
  • Parametric study of coolant-injection flow through different pore geometrical patterns for injection flow control in hypersonic flow

    Cerminara, Adriano; Adebayo, David Shina; Baroutaji, Ahmad; Arjunan, Arun (Interpore, 2022-05-31)
  • Cyclic guanidine containing amino acids that promote glucocerebrosidase

    Al-Taie, Zahraa S; Bartholomew, Barbara; Coles, Simon J; Evans, Daniel M; Hollinshead, Jackie; Jones, Leigh F; Kraehenbuehl, Rolf; Murphy, Patrick J; Nash, Robert J; Penkova, Yana B; et al. (Elsevier, 2022-08-24)
    Novel cyclic guanidine containing amino acids (S)-1, 2 and 3 were prepared from l-serine 5. (S)-2-Imino-3-methylimidazolidine-4-carboxylic acid hydrochloride salt 2. HCl and (3S, 6S)-3,6-bis(hydroxymethyl)-1,4-dimethylpiperazine-2,5-dione 15 showed in vitro promotion of the enzyme glucocerebrosidase.
  • Aberrant expression of miR-133a in endothelial cells inhibits angiogenesis by reducing pro-angiogenic but increasing anti-angiogenic gene expression

    Ahmed, Suhail; Kurusamy, Sathishkumar; David, Ezra Leander Santhosh; Khan, Kinza; Kalyanakrishnan, Krithika; Ian-Gobo, Miebaka; Kola, Teja Manidhar; Wilkinson, Robert N; Kannappan, Vinodh; Wang, Weiguang; et al. (Springer, 2022-08-30)
    Angiogenesis is a multi-factorial physiological process deregulated in human diseases characterised by excessive or insufficient blood vessel formation. Emerging evidence highlights a novel role for microRNAs as regulators of angiogenesis. Previous studies addressing the effect of miR-133a expression in endothelial cells during blood vessel formation have reported conflicting results. Here, we have assessed the specific effect of mature miR-133a strands in angiogenesis and the expression of endothelial angiogenic genes. Transfection of miR-133a-3p or -5p mimics in primary human endothelial cells significantly inhibited proliferation, migration, and tubular morphogenesis of transfected cells. Screening of gene arrays related to angiogenic processes, and further validation by TaqMan qPCR, revealed that aberrant expression of miR-133a-3p led to a decrease in the expression of genes encoding pro-angiogenic molecules, whilst increasing those with anti-angiogenic functions. Ingenuity Pathway Analysis of a collection of genes differentially expressed in cells harbouring miR-133a-3p, predicted decreased cellular functions related to vasculature branching and cell cycle progression, underlining the inhibitory role of miR-133a-3p in angiogenic cellular processes. Our results suggest that controlled delivery of miR-133a-3p mimics, or antagomirs in diseased endothelial cells, might open new therapeutic interventions to treat patients suffering from cardiovascular pathologies that occur with excessive or insufficient angiogenesis.
  • PLGA-nano-encapsulated disulfiram inhibits hypoxia-induced NF-κB, cancer stem cells, and targets glioblastoma in vitro and in vivo

    Kannappan, Vinodh; Liu, Ying; Wang, Zhipeng; Azar, Karim; Kurusamy, Sathishkumar; Kilari, Rajagopal Sharada; Armesilla, Angel; Najlah, Mohammad; Liu, Peng; Bian, Xiu-Wu; et al. (American Association for Cancer Research, 2022-08-02)
    Glioblastoma stem cell (GSC) is the major cause of glioblastoma multiforme (GBM) chemotherapy failure. Hypoxia is one of the determinants of GSC. NF-κB plays a pivotal link between hypoxia and cancer stem cells (CSCs). Disulfiram, an antialcoholism drug, has very strong NF-κB-inhibiting and anti-CSC activity. In this study, the in vitro anti-GSC activity of disulfiram and in vivo anti-GBM efficacy of poly lactic-co-glycolic acid nanoparticle-encapsulated disulfiram (DS-PLGA) were examined. We attempt to elucidate the molecular network between hypoxia and GSCs and also examined the anti-GSC activity of disulfiram in vitro and in vivo. The influence of GSCs and hypoxia on GBM chemoresistance and invasiveness was studied in hypoxic and spheroid cultures. The molecular regulatory roles of NF-κB, hypoxia-inducible factor-1α (HIF1α), and HIF2α were investigated using stably transfected U373MG cell lines. The hypoxia in neurospheres determines the cancer stem cell characteristics of the sphere-cultured GBM cell lines (U87MG, U251MG, U373MG). NF-κB is located at a higher hierarchical position than HIF1α/HIF2α in hypoxic regulatory network and plays a key role in hypoxia-induced GSC characters. DS inhibits NF-κB activity and targets hypoxia-induced GSCs. It showed selective toxicity to GBM cells, eradicates GSCs, and blocks migration and invasion at very low concentrations. DS-PLGA efficaciously inhibits orthotopic and subcutaneous U87MG xenograft in mouse models with no toxicity to vital organs.
  • Community pharmacy brief screening intervention to improve health outcomes for patients diagnosed with chronic diseases

    Arikawe, Olutayo; Morrissey, Hana; Ball, Patrick (SPER Publications and Solutions Pvt. Ltd., 2022-07-31)
    This study aimed to develop a new screening model designed for use in community pharmacies, to support people living with chronic health conditions. We hypothesized that poor memory and mental health may affect patients’ level of adherence to medications and selfcare, resulting in poor long-term health outcomes. There were three main interventions: screening for adherence, mental health, and memory; referral as required to other healthcare professionals and medication optimization. In addition to demographics, four validated tools were used: the Morisky 8-items scale, the clinically useful anxiety scale, the clinically useful depression scale, and the dementia UK concerned about your memory questionnaire. All pharmacy staff who were involved in the delivery of the model received prior training and certification. To ensure safety for all concerned, pharmacists and their staff involved in the study also received training and certification in Mental Health First Aid. The study concluded that the designed model is workable for delivery from community pharmacies. Community pharmacies are better placed too early intervene at the point of medication dispensing (initiation or repeat) to engage with the patient and share or review information about their conditions and medications, the consequences of good and poor adherence to therapy, and clarify their responsibility in self-management. The self-completed screening surveys for adherence, mental health, and cognitive function also proved successful to ensure that the patient is capable to undertake self-management task, pharmacology, lifestyle, and self-care, which is passed to them from their treating teams while they are waiting for their prescriptions.
  • Recent advances in repurposing disulfiram and disulfiram derivatives as copper-dependent anticancer agents

    Kannappan, Vinodh; Ali, Misha; Small, Benjamin; Rajendran, Gowtham; Elzhenni, Salena; Taj, Hamza; Wang, Weiguang; Dou, Q. Ping; Research Institute in Healthcare Science, Faculty of Science and Engineering, University of Wolverhampton, Wolverhampton, United Kingdom. (Frontiers Media, 2021-09-17)
    Copper (Cu) plays a pivotal role in cancer progression by acting as a co-factor that regulates the activity of many enzymes and structural proteins in cancer cells. Therefore, Cu-based complexes have been investigated as novel anticancer metallodrugs and are considered as a complementary strategy for currently used platinum agents with undesirable general toxicity. Due to the high failure rate and increased cost of new drugs, there is a global drive towards the repositioning of known drugs for cancer treatment in recent years. Disulfiram (DSF) is a first-line antialcoholism drug used in clinics for more than 65 yr. In combination with Cu, it has shown great potential as an anticancer drug by targeting a wide range of cancers. The reaction between DSF and Cu ions forms a copper diethyldithiocarbamate complex (Cu(DDC)2 also known as CuET) which is the active, potent anticancer ingredient through inhibition of NF-κB and ubiquitin-proteasome system as well as alteration of the intracellular reactive oxygen species (ROS). Importantly, DSF/Cu inhibits several molecular targets related to drug resistance, stemness, angiogenesis and metastasis and is thus considered as a novel strategy for overcoming tumour recurrence and relapse in patients. Despite its excellent anticancer efficacy, DSF has proven unsuccessful in several cancer clinical trials. This is likely due to the poor stability, rapid metabolism and/or short plasma half-life of the currently used oral version of DSF and the inability to form Cu(DDC)2 at relevant concentrations in tumour tissues. Here, we summarize the scientific rationale, molecular targets, and mechanisms of action of DSF/Cu in cancer cells and the outcomes of oral DSF ± Cu in cancer clinical trials. We will focus on the novel insights on harnessing the immune system and hypoxic microenvironment using DSF/Cu complex and discuss the emerging delivery strategies that can overcome the shortcomings of DSF-based anticancer therapies and provide opportunities for translation of DSF/Cu or its Cu(DDC)2 complex into cancer therapeutics.
  • Phenotypic variation in Xenopus laevis tadpoles from contrasting climatic regimes is the result of adaptation and plasticity

    Kruger, Natasha; Secondi, Jean; du Preez, Louis; Herrel, Anthony; Measey, John (Springer, 2022-08-22)
    Phenotypic variations between populations often correlate with climatic variables. Determining the presence of phenotypic plasticity and local adaptation of a species to different environments over a large spatial scale can provide insight on the persistence of a species across its range. Amphibians, and in particular their larvae, are good models for studies of phenotypic variation as they are especially sensitive to their immediate environment. Few studies have attempted to determine the mechanisms that drive phenotypic variation between populations of a single amphibian species over a large spatial scale especially across contrasting climatic regimes. The African clawed frog, Xenopus laevis, occurs in two regions with contrasting rainfall regimes in southern Africa. We hypothesised that the phenotypic variation of life-history traits of X. laevis tadpoles emerges from a combination of plastic and genetic responses. We predicted that plasticity would allow the development of tadpoles from both regions in each environment. We also predicted that local adaptation of larval traits would drive the differentiation of reaction norms between populations and lower survival in tadpoles reared away from their home environment. We measured growth, time to metamorphosis, and survival in a reciprocal transplant experiment using outdoor mesocosms. Supporting our prediction, we found that the measured variation of all traits was explained by both adaptation and plasticity. However, the reaction norms differed between populations suggesting adaptive and asymmetric plasticity. All tadpoles experienced lower survival when translocated, but only translocated tadpoles from the winter rainfall region matched survival of local tadpoles. This has implications for the dynamics of translocated X. laevis into novel environments, especially from the winter rainfall region. Our discovery of their asymmetric capacity to overcome novel environmental conditions by phenotypic plasticity alone provides insight into their invasion success.
  • Structural integrity evaluation of cyclic loading glass fibre reinforced polymer composite by acoustic emission and heat transfer

    Loganathan, Thozhuvur Govindaraman; Kalidas, Vinoth Kumar; Bari, Dr. Klaudio; Chadalavala, Hemadri; Venkatachalam, Gopalan (SAGE, 2022-08-19)
    GFRP composites experience structural changes like matrix cracking, debonding, delamination, and fibre failure on static and dynamic loading. In this work, composites with varying fibre orientation interaction angle and volume fractions are prepared and exposed to cyclic load. The cyclic load (R = 0) is a constant amplitude flexural load imposed on the cantilever beam specimen with varying frequencies (2.6, 4.6, 8.6 Hz) and cycles (up to 44 × 103). The structural integrity of the specimens on loading is examined in terms of Flexural, modulus, Acoustic Emission (AE) and heat transfer changes. The drop in flexural modulus is minimum in higher Vf = 32% laminate (A1 = 7.01%, B1 = 1.86%) than the lower Vf = 25% (A2 = 19.86%, B2 = 8.6%). The observed AE peak frequency for the induced damages is in the range of 50–100, 110–230, 245–380 kHz. The drop-in fibre volume fraction has a significant role in laminate with lower fibre interaction (Type A) to offer minimum variation (5.25%) in AE activity count which is the opposite in laminates with higher fibre interaction angle (31.75%). The step heat thermography exhibits minimum temperature difference (∆T) for moderate loading frequency and in a few cases, ∆T drops well below the virgin, insisting on in situ thermography to study the dynamic changes in composites. A fibre dominant behaviour can be observed with minimum variation in AE activity in a lower fibre interaction angle. Thus, the fibre orientation angle and fibre volume fraction have a significant role in the retention of the structural integrity of composites in dynamic loading.
  • Towards an interpretable model for automatic classification of endoscopy images

    García-Aguirre, Rogelio; Torres Treviño, Luis; Navarro-López, Eva María; González-González, José Alberto; Pichardo Lagunas, Obdulia; Martínez Seis, Bella; Martínez-Miranda, Juan (Springer, 2022-12-31)
    Deep learning strategies have become the mainstream for computer-assisted diagnosis tools development since they outperform other machine learning techniques. However, these systems can not reach their full potential since the lack of understanding of their operation and questionable generalizability provokes mistrust from the users, limiting their application. In this paper, we generate a Convolutional Neural Network (CNN) using a genetic algorithm for hyperparameter optimization. Our CNN has state-of-the-art classification performance, delivering higher evaluation metrics than other recent papers that use AI models to classify images from the same dataset. We provide visual explanations of the classifications made by our model implementing Grad-CAM and analyze the behavior of our model on misclassifications using this technique.

View more