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Abstract This study investigates the development of thermoplastic polyurethane (TPU) filaments incorporating multi‐walled carbon nanotubes (MWCNT) to enhance strain‐sensing capabilities. Various MWCNT reinforcement ratios are used to produce customized feedstock for fused filament fabrication (FFF) 3D printing. Mechanical properties and the piezoresistive response of samples printed with these multifunctional filaments are concurrently evaluated. Surface morphology and microstructural observations reveal that higher MWCNT weight percentages increase filament surface roughness and rigidity. The microstructural modifications directly influence the tensile strength and strain energy of the printed samples. The study identifies an apparent percolation threshold within the 10–12 wt.% MWCNT range, indicating the formation of a conductive network. At this threshold, higher gauge factors are achieved at lower strains. A newly introduced Electro‐Mechanical Sensitivity Ratio (ESR) parameter enables the classification of composite behaviors into two distinct zones, offering the ability to tailor self‐sensing structures with on‐demand properties. Finally, flexible structures with proven application in soft robotics and shape morphing are fabricated and tested at different loading conditions to demonstrate the potential applicability of the custom filaments produced. The results highlight a pronounced piezoresistive response and superior load‐bearing performance in the examined structures.

Summary: Integrated carbon capture and utilization (CCU) is appealing for in situ production of fuels and chemicals. Here, we propose and subsequently assess an integrated electrochemical CCU process and compare it with a carbon capture and storage (CCS) route from economic and environmental perspectives. This analysis reveals that under a baseline CCU scenario, carbon products reap either economic (67% and 10% gross margin increase for carbon monoxide [CO] and n-propanol, respectively) or environmental benefits (formic acid production would reduce ∼721 thousand ton carbon dioxide equivalent [CO2e]/year) relative to the CCS route. Under an optimistic scenario, while all of the carbon dioxide (CO2)-derived products are economically compelling over the CCS route, only formic acid production would reduce ∼1,465 thousand ton CO2e/year over CCS (∼575 thousand ton CO2e/year). This study may serve as a framework to decide whether a CCS or a CCU pathway would be compelling under a given scenario when fuel-cell-based CO2 capture technology is used to reduce carbon emissions and create economic value from fossil fuel-based power plants.

Open educational resources (OER) have become increasingly popular in recent times. Here, the aim was to synthesise the lessons learned through the development of OER materials for a university-level course called “environmental modelling„. Consequently, the topics of discussion included: (i) how to choose an appropriate creative commons license; (ii) ways of incorporating materials from other sources, such as publicly available sources, other open access materials, and an author’s own published materials if not published under a creative commons license; (iii) the impact of the developed OER in the field of environmental modelling; and (iv) the challenges in developing OER material. Upon developing the materials, we observed the following: (i) students enrolled in the course did not purchase textbooks; (ii) our OER materials ranked as one of the most accessed (i.e., number 7) materials according to the usage data that summed the number of file downloads and item views from PRISM (i.e., the hosting platform maintained by the University of Calgary); (iii) the students learned relatively better as per the data acquired by the University of Calgary’s universal student ratings of instruction (USRI) instrument; and (iv) other universities expressed interest in adopting the materials.

Open educational resources (OER) have become increasingly popular in recent times. Here, the aim was to synthesise the lessons learned through the development of OER materials for a university-level course called "environmental modelling". Consequently, the topics of discussion included: (i) how to choose an appropriate creative commons license; (ii) ways of incorporating materials from other sources, such as publicly available sources, other open access materials, and an author's own published materials if not published under a creative commons license; (iii) the impact of the developed OER in the field of environmental modelling; and (iv) the challenges in developing OER material. Upon developing the materials, we observed the following: (i) students enrolled in the course did not purchase textbooks; (ii) our OER materials ranked as one of the most accessed (i.e., number 7) materials according to the usage data that summed the number of file downloads and item views from PRISM (i.e., the hosting platform maintained by the University of Calgary); (iii) the students learned relatively better as per the data acquired by the University of Calgary's universal student ratings of instruction (USRI) instrument; and (iv) other universities expressed interest in adopting the materials.

Although the unforeseen shocks of the global inflation crisis of 2021-2022 rattled business practitioners, investors, and policy-makers, prior research on this phenomenon is centered on ‘mainstream’ business organizations, while the scholarly attention on informal micro-entrepreneurship businesses in the context of crisis management has been relatively sparse. This qualitative study intends to fill this gap in entrepreneurial crisis management literature by investigating the first-hand account of the adversity of the crisis and management practices as the inflation crisis unfolds. Based on semi-structured interviews and the interpretative phenomenological analysis (IPA) method with 16 informal micro-entrepreneurs from four different informal microenterprise sectors (service, trade, manufacturing, and agricultural) in Thailand, the findings revealed that this sector endured inflationary constraints related to customer base, profit margin, cash holding, and household borrowing. This study simultaneously demonstrates how informal micro-entrepreneurs bricolage responses by optimizing inventory agility and transformative supplier partnerships that shaped the immediate adjustments and doubling down on customer services, offering disruptive products and services, and digital shifting contributed to developing long-term resilient practices to navigate the inflation crisis. Furthermore, to advance our theoretical understanding for bolstering inflation crisis preparedness of micro-entrepreneurship via strategic policy responses with implications for policy-makers are also discussed.

Reliable and widely accepted, renewable energy sources stand as the optimal substitute for fossil fuels in meeting our growing energy demands. Specifically, solar energy can be harnessed into electrical power through solar cells. Many solar installations are situated in remote locations like rooftops, mountains, and deserts. Effective monitoring of these solar photovoltaic systems is crucial to maximize their performance. Monitoring solutions come in various configurations. The simplest approach involves offline data collection, entailing the placement of a data collection device on the installation which then stores data locally for a specific timeframe. However, this conventional monitoring method falls short in providing real-time data. In contrast, leveraging Internet of Things (IoT) technology to oversee solar photovoltaic power generation offers a substantial performance boost. This project aims to develop an IoT-powered system for real-time remote monitoring of solar photovoltaic installations. The collected data is stored in the IoT cloud, accessible through an application via an active internet connection from anywhere worldwide. This grants immediate insights into the installation’s status, facilitating maintenance and prompt fault detection.

Summary: The catastrophic declines of three species of 'Critically Endangered' Gyps vultures in South Asia were caused by unintentional poisoning by the non-steroidal anti-inflammatory drug (NSAID) diclofenac. Despite a ban on its veterinary use in 2006 (India, Nepal, Pakistan) and 2010 (Bangladesh), residues of diclofenac have continued to be found in cattle carcasses and in dead wild vultures. Another NSAID, meloxicam, has been shown to be safe to vultures. From 2012 to 2018, we undertook covert surveys of pharmacies in India, Nepal and Bangladesh to investigate the availability and prevalence of NSAIDs for the treatment of livestock. The purpose of the study was to establish whether diclofenac continued to be sold for veterinary use, whether the availability of meloxicam had increased and to determine which other veterinary NSAIDs were available. The availability of diclofenac declined in all three countries, virtually disappearing from pharmacies in Nepal and Bangladesh, highlighting the advances made in these two countries to reduce this threat to vultures. In India, diclofenac still accounted for 10–46% of all NSAIDs offered for sale for livestock treatment in 2017, suggesting weak enforcement of existing regulations and a continued high risk to vultures. Availability of meloxicam increased in all countries and was the most common veterinary NSAID in Nepal (89.9% in 2017). Although the most widely available NSAID in India in 2017, meloxicam accounted for only 32% of products offered for sale. In Bangladesh, meloxicam was less commonly available than the vulture-toxic NSAID ketoprofen (28% and 66%, respectively, in 2018), despite the partial government ban on ketoprofen in 2016. Eleven different NSAIDs were recorded, several of which are known or suspected to be toxic to vultures. Conservation priorities should include awareness raising, stricter implementation of current bans, bans on other vulture-toxic veterinary NSAIDs, especially aceclofenac and nimesulide, and safety-testing of other NSAIDs on Gyps vultures to identify safe and toxic drugs. [ABSTRACT FROM AUTHOR]

Entropy stabilized oxides (ESOs) are a new class of stable hybrids and single phase metal oxides made from multiple ions with material properties somewhere between the constituent oxides, or occasionally entirely new properties. One of the limitations of ESOs is their energy-intensive fabrication process, which has resulted in slow development and scale-up of new ESOs. In this work, we present a novel energy-efficient ESO synthesis method that uses the ability of carbonaceous materials to heat rapidly in response to radio frequency (RF) fields in 1–200 MHz range. Using carbon fibers and graphene as RF susceptors, synthesis of (Mg0·2Co0·2Ni0·2Cu0·2Zn0.2)O is achieved through RF-initiated combustion synthesis with heating rates of 203 °C/s at 20 W of input power. This method reduces the formation time of ESOs to less than a minute, allowing for much more efficient fabrication. The corresponding morphology and composition of the as-synthesized ESO-carbon fiber and ESO-graphene were studied using extensive spectroscopy and characterization. Additionally, single carbon fibers coated with ESO were tested for tensile strength and modulus; little change in mechanical properties was observed as compared to pristine fibers. This work opens an exciting frontier for the rapid synthesis of ESO-carbon composites using RF heating as a non-contact, rapid, and efficient manufacturing process.

The electricity crisis is a common issue in Bangladesh; however, recently the electricity scenario has been getting worse due to various reasons including power generation and distribution all over the country. Meanwhile, the large number of people requires a huge amount of energy which is not possible to be met by the national grid due to the limited power generation from different plants. Among all renewable energy sources, the solar photovoltaics (PV) system is the best choice as a generation source, either off-grid or with a grid-tied connection, to reduce the pressure on the national grid. In Bangladesh, there are more than 175,000 schools, and it is possible to generate a huge amount of renewable (solar) power to supply all the schools by using rooftop PV systems. We propose a new approach that combines solar energy harvesting and savings to make the schools self-sufficient and energywise. We performed a Hybrid Optimization Model for Multiple Energy Resources (HOMER) pro simulation and find that it was possible to generate approximately 200 megawatts (MW) of power. We conducted a feasibility study on generating power from rooftop PV systems on school buildings and reduced the power consumption using retrofitted thin-film-coated glass by around 16–20% per day depending on the school size, which can help the national power grid system by either making all the schools off-grid or grid-connected to supply power to the national grid. In addition, we perform a HelioScope simulation to investigate the maximum upscaling of PV sizing for the rooftops of school buildings in Bangladesh to realize how to make each school a mini solar power station in the future. The HelioScope simulation performance showed that it was possible to generate approximately 96,993 kWh per year from one school building.

Abstract Background Twitter is a popular social networking site where short messages or “tweets” of users have been used extensively for research purposes. However, not much research has been done in mining the medical professions, such as detecting the occupations of users from their biographical contents. Mining such professions can be used to build efficient recommender systems for cost-effective targeted advertisements. Moreover, it is highly important to develop effective methods to identify the occupation of users since conventional classification methods rely on features developed by human intelligence. Although, the result may be favorable for the classification problem. However, it is still extremely challenging for traditional classifiers to predict the medical occupations accurately since it involves predicting multiple occupations. Hence this study emphasizes predicting the medical occupational class of users through their public biographical (“Bio”) content. We have conducted our analysis by annotating the bio content of Twitter users. In this paper, we propose a method of combining word embedding with state-of-art neural network models that include: Long Short Term Memory (LSTM), Bidirectional LSTM, Gated Recurrent Unit, Bidirectional Encoder Representations from Transformers, and A lite BERT. Moreover, we have also observed that by composing the word embedding with the neural network models there is no need to construct any particular attribute or feature. By using word embedding, the bio contents are formatted as dense vectors which are fed as input into the neural network models as a sequence of vectors. Result Performance metrics that include accuracy, precision, recall, and F1-score have shown a significant difference between our method of combining word embedding with neural network models than with the traditional methods. The scores have proved that our proposed approach has outperformed the traditional machine learning techniques for detecting medical occupations among users. ALBERT has performed the best among the deep learning networks with an F1 score of 0.90. Conclusion In this study, we have presented a novel method of detecting the occupations of Twitter users engaged in the medical domain by merging word embedding with state-of-art neural networks. The outcomes of our approach have demonstrated that our method can further advance the process of analyzing corpora of social media without going through the trouble of developing computationally expensive features.

Analysis of long-term datasets on bird populations can be used to answer ecological and management questions that are useful for conservation. Tanguar Haor (9500 ha) is one of the major freshwater wetlands in Bangladesh and supports a large number of migratory and resident waterbirds. Because of its unique ecological and economic values, it is arguably the most notable wetland in the floodplains of northeast Bangladesh and in the region. This Ramsar site supports globally important populations of threatened waterbirds, such as the Baer’s Pochard Aythya baeri, Common Pochard Aythya ferina, Falcated Duck Mareca falcata, Ferruginous Duck Aythya nyroca, Oriental Darter Anhinga melanogaster, and Black-tailed Godwit Limosa limosa. Considering the international significance of this site, knowledge gaps on waterbird population trends, and key ecological factors, we conducted waterbird census between 2008 and 2021 to identify priority sites for conservation, population trends of resident and migratory waterbirds, and environmental factors that influence their abundances. We recorded a total of 69 species of waterbirds (maximum count of 166,788 individuals in 2013) and assessed population trends of 47 species. Of these, peak counts of 15 species exceeded the 1% threshold of their Asian-Australian Flyway population estimates. Most species (59%) showed a declining trend, including the critically endangered Baer’s Pochard and the vulnerable Common Pochard, and 16 species (41%) showed an increasing trend. Based on the abundance and species diversity, we have identified Chotainna beel and Lechuamara beel as conservation priority sites within the Haor complex and discuss key threats to these areas. We also offer evidence that adjusting water-level management to annual rainfall patterns could be a useful intervention for waterbird management. Involving local communities in conservation efforts by creating bird sanctuaries within the Haor complex will strengthen waterbird conservation in the country and along the East Asian-Australian Flyway.

Honeycomb structures are widely used in applications that require excellent strain energy mitigation at low structural weights. The load-bearing and energy absorption capacity of honeycomb structures strongly depend on their cell wall thickness to edge ratios. This work studies the mechanical response and strain energy absorption characteristics of hexagonal honeycomb structures with various cell wall thicknesses in response to out-of-plane loading conditions. Honeycomb structures with various nominal densities are first additively manufactured from flexible thermoplastic polyurethane (TPU). A comprehensive experimental study characterized the mechanical strength, energy absorption performance, and the strain recoverability of the structures. Density-graded structures are then fabricated by stacking multiple density layers of the honeycombs. Mechanical characterization of the density-graded structures points to their superior load-bearing response at large deformation conditions. From a strain energy absorption perspective, density graded structures are shown to outperform their uniform density counterparts at small deformation conditions. The results obtained in this work highlight the significance of density gradation as a practical means for the development of honeycomb structures with highly tailorable, application-specific mechanical properties.

Although the utilizing of renewable energy sources (RESs) in microgrid (MG) offers a recognized solution to meet the increasing demand, it’s performance depend on various meteorological factors of RESs. Again, the functioning of MGs is often affected with certain industrial load dynamics which allowing them to alter the operating region and tracking function of the MGs. The above-mentioned challenges motivate us to design the ancillary voltage control design for enabling the MGs to provide adaptive transient and tracking voltage responses over the changes of various factors like weather, consumer demand, and industrial loads. Firstly, we design an intelligent adaptive control (IAC) framework made by merging with proportional-integral (PI) regulator and artificial neural network (ANN) to sustain the regulated common bus voltage over the mentioned changes. The regulated bus voltage is forwarded to operate the industrial loads via the regulation of inverter-based secondary network (SN). A study on the variation of weather condition and consumer demand is done to show the efficacy of the IAC framework. Secondly, we propose a novel fixed control structure named model reference modified fractional-order PID (MR-F0PID) regulator to maintain the high tracking response of the MG via the control of inverter associated with the SNs. The tracking competency of this fixed control framework is analyzed over the running of a few industrial loads dynamics associated with single-phase inverter based SN and results are compared with the other related existing controllers. Moreover, a mathematical analysis for mapping the stable region is completed here to track down the closed-loop stability area. As a further study, the three-phase inverter based SN associated with several three-phase industrial load is also considered with the same DC bus and analyzed to observe the competency of the proposed fixed MR-FOPID control framework.

This research reports on the design, fabrication, and multiscale mechanical characterization of flexible, planar mechanical metamaterials with tailorable mechanical properties. The tunable mechanical behavior of the structures is realized through the introduction of orthogonal perforations with different geometric features. Various configurations of the perforations lead to a wide range of Poisson’s ratios (from −0.8 to 0.4), load-bearing properties, and energy absorption capacities. The correlations between the configuration of the perforations and the auxetic response of the structures are highlighted through computational and experimental characterizations performed at multiple length scales. It is demonstrated that the local in-plane rotation of the solid ligaments in a uniaxially loaded structure is the primary factor that contributes to its strain-dependent auxetic behavior at macroscopic scales. Confinement of these local rotations is then used as a practical strategy to activate a self-strengthening mechanism in the auxetic structures. It is further shown that the fabrication of planar flexible structures with controllable Poisson’s ratios is feasible through spatial adjustment of perforations in the structure. Finally, discussions are provided regarding the practical applications of these structures for a new generation of highly energy-absorbing protective equipment.