Long-term Integrity Research Articles

EVALUATING THE PLA AGING EFFECTS ON THE MECHANICAL PERFORMANCE OF 3D-PRINTED COMPONENTS

The aging influence on the mechanical performance of bio-degradable polymers holds significant importance in additive manufacturing, particularly in structural applications. Understanding the changes in mechanical properties over time is crucial for ensuring the long-term sustainability and reliability of polymer-based structures. Thus, this study aims to comprehensively evaluate the effects of aging on polylactic acid (PLA) by analyzing its failure mechanisms of 3D-printed samples subjected to compression load. To achieve this goal, specimens of PLA were exposed to natural environmental conditions for varying periods. Subsequently, the mechanical characteristics of the additively produced component were assessed after each exposure, providing valuable insights into its performance at different stages of aging. By quantifying the material’s ability to withstand applied forces, the study enables the prediction of its long-term structural integrity. In addition, the investigation of failure mechanisms aids in understanding the modes of failure that PLA may undergo as it ages. This knowledge is essential for developing strategies to prevent structural failures and enhance the overall reliability of PLA-based applications. The findings contribute to advancing the field of additive manufacturing, enabling PLA’s sustainable and reliable application in various industries.

Understanding Canada's Private Sponsorship Program: Its origins, features, and consequences

This article highlights features of Canada's private sponsorship program and ex-plains its consequences and performance. It explores which actors were involved in the private sponsorship, how domestic circumstances stimulated the application of the program, and it discusses its intended and unintended consequences. The author examines the profile of the Syrian refugees and discusses how personal characteristics may affect integration trajectories. Private sponsorship is consid-ered more effective than government-assisted sponsorship as it ensures a smooth-er, faster, and long-term integration of refugees. However, the author argues that personal profiles could play a critical role in integration process, and therefore, measuring the program's performance by only comparing it with a government-assisted program could be challenging.

Design and Optimization of English-Speaking Teaching Model Using Virtual Reality Technology

The advent of virtual reality (VR) technology has ushered in a new era in language education, offering innovative avenues for immersive and interactive learning experiences. This paper introduces a groundbreaking English speaking teaching model designed to harness the power of VR technology. Rooted in the imperative for authentic language practice, our model transports learners into virtual environments meticulously crafted to replicate real-life scenarios. Here, learners engage in conversational interactions, from everyday dialogues to professional exchanges, facilitated by interactive conversational agents. Complementing this immersive experience are adaptive learning algorithms that tailor exercises to individual proficiency levels, alongside multi-modal feedback mechanisms providing comprehensive guidance on pronunciation, intonation, and language usage. Through iterative refinement and a rigorous design methodology, our model seeks to enhance learner engagement, motivation, and proficiency across diverse skill levels.Preliminary pilot studies underscore the model's promise, with participants reporting heightened satisfaction, motivation, and perceived progress in English speaking skills. As we tread further into this innovative domain, future research avenues beckon, including investigations into long-term effectiveness, scalability, and integration into formal education systems. The convergence of VR technology and language education represents a paradigm shift, poised to redefine the dynamics of language acquisition and proficiency in an increasingly interconnected world.

Functionalized nanowires for miRNA-mediated therapeutic programming of naïve T cells.

Cellular programming of naïve T cells can improve the efficacy of adoptive T-cell therapy. However, the current ex vivo engineering of T cells requires the pre-activation of T cells, which causes them to lose their naïve state. In this study, cationic-polymer-functionalized nanowires were used to pre-program the fate of primary naïve CD8+ T cells to achieve a therapeutic response in vivo. This was done by delivering single or multiple microRNAs to primary naïve mouse and human CD8+ T cells without pre-activation. The use of nanowires further allowed for the delivery of large, whole lentiviral particles with potential for long-term integration. The combination of deletion and overexpression of miR-29 and miR-130 impacted the ex vivo T-cell differentiation fate from the naïve state. The programming of CD8+ T cells using nanowire-delivered co-delivery of microRNAs resulted in the modulation of T-cell fitness by altering the T-cell proliferation, phenotypic and transcriptional regulation, and secretion of effector molecules. Moreover, the in vivo adoptive transfer of murine CD8+ T cells programmed through the nanowire-mediated dual delivery of microRNAs provided enhanced immune protection against different types of intracellular pathogen (influenza and Listeria monocytogenes). In vivo analyses demonstrated that the simultaneous alteration of miR-29 and miR-130 levels in naïve CD8+ T cells reduces the persistence of canonical memory T cells whereas increases the population of short-lived effector T cells. Nanowires could potentially be used to modulate CD8+ T-cell differentiation and achieve a therapeutic response in vivo without the need for pre-activation.

Cointegration analysis of GDP indicators per capita between the Republic of Azerbaijan and Turkey on purchasing power parity

The article analyses the interrelationships between the main components of socio-economic development levels in Turkey and the Republic of Azerbaijan. The purpose of this work is to construct a cross-country regression model of per capita economic growth in Turkey and the Republic of Azerbaijan and to conduct a cross-country comparative analysis of the main components of inclusive growth under the strong influence of both countries. The aim of this research is to enable empirical study of the joint movement of both indicators, determine cause-effect relationships and co-integration dependence, establish long-term integration relationships, and take necessary steps and measures for a positive outcome. The level of economic development was measured using GDP per capita with purchasing power parity (PPP). The study analyses the dynamic interaction of indicators using data from January 1992 to December 2022. Econometric methodology was employed, including the extended Dickey-Fuller test to detect a single root, and the Granger test. The Johansen test, Error correction model, and ARDL model standard diagnostic tests were used to examine the cointegration relationship. Stationarity, causality, and cointegration tests were conducted on the entire sample at a significance level of 10%.

Long-Term Coherent Integration Algorithm for High-Speed Target Detection.

Long-term coherent integration (CI) can effectively improve the radar detection capability for high-speed targets. However, the range walk (RW) effect caused by high-speed motion significantly degrades the detection performance. To improve detection performance, this study proposes an improved algorithm based on the modified Radon inverse Fourier transform (denoted as IMRIFT). The proposed algorithm uses parameter searching for velocity estimation, designs a compensation function based on the relationship between velocity and distance walk and Doppler ambiguity terms, and performs CI based on the compensated signal. IMRIFT can achieve RW correction, avoid the blind-speed sidelobe (BSSL) effect caused by velocity mismatch, and improve detection performance, while ensuring low computational complexity. In addition, considering the relationship between energy concentration regions and bandwidth in the 2D frequency domain, a fast method based on IMIRFT is proposed, which can balance computational cost and detection capacity. Finally, a series of comparative experiments are conducted to demonstrate the effectiveness of the proposed algorithm and the fast method.

Evaluating the World’s First Sovereign Blue Bond: Lessons for Operationalising Blue Finance

The Seychelles blue bond is an innovative finance mechanism that has played a pivotal role in shaping the global landscape of blue bonds. Seychelles leadership in the blue economy sets a significant precedent. However, this precedent has also raised concerns among various stakeholders. This study evaluates of Seychelles’ sovereign blue bond, which was co-developed by the government of Seychelles and the World Bank. Three themes are explored, how the blue bond relates to other actors and donors in the blue economy space of Seychelles; how the blue bond contributes to advancing the national agenda and blue economy of Seychelles; and the key strengths, enablers and weaknesses of the blue bond. A series of considerations for future blue financing and blue bond mechanisms are presented, based on the findings of this study, to ensure that financing extends beyond blue washing and contributes meaningfully to the holistic transition to a sustainable blue economy. Our findings imply significant considerations for stakeholders in sustainable finance, suggesting ways to enhance the efficacy of blue bonds and emphasising the need for further research on their long-term impact and integration with other financial instruments.

Experimental Data on Maximum Swelling Pressure of Clayey Soils and Related Soil Properties

Clayey soils exhibit significant volumetric changes in response to variations in water content. The swelling pressure of clayey soils is a critical parameter for evaluating the stability and performance of structures built on them, facilitating the development of appropriate design methodologies and mitigation strategies to ensure their long-term integrity and safety. We present a dataset comprising maximum swelling pressure values from 759 compacted soil samples, compiled from 16 articles published between 1994 and 2022. The dataset is classified into two main groups: 463 samples of natural clays and 296 samples of bentonite and bentonite mixtures, providing data on various types of soils and their properties. Different swelling test methods, including zero swelling, swell consolidation, restrained swell, double oedometer, free swelling, constant volume oedometer, UPC isochoric cell, isochoric oedometer and consolidometer, were employed to measure the maximum swelling pressure. The comprehensive nature of the dataset enhances its applicability for geotechnical projects. The dataset is a valuable resource for understanding the complex interactions between soil properties and swelling behavior, contributing to advancements in soil mechanics and geotechnical engineering.

Oligodendrocytes: Myelination, Plasticity, and Axonal Support.

The myelination of axons has evolved to enable fast and efficient transduction of electrical signals in the vertebrate nervous system. Acting as an electric insulator, the myelin sheath is a multilamellar membrane structure around axonal segments generated by the spiral wrapping and subsequent compaction of oligodendroglial plasma membranes. These oligodendrocytes are metabolically active and remain functionally connected to the subjacent axon via cytoplasmic-rich myelinic channels for movement of metabolites and macromolecules to and from the internodal periaxonal space under the myelin sheath. Increasing evidence indicates that oligodendrocyte numbers, specifically in the forebrain, and myelin as a dynamic cellular compartment can both respond to physiological demands, collectively referred to as adaptive myelination. This review summarizes our current understanding of how myelin is generated, how its function is dynamically regulated, and how oligodendrocytes support the long-term integrity of myelinated axons.

Sonication assisted superior anti-corrosion properties of cathodically deposited novel nickel-graphene oxide-zinc oxide coating

This study details the sonication-assisted synthesis and characterization of a cathodically deposited novel nickel-graphene oxide -zinc oxide (Ni-GO-ZnO) composite coating achieved through electrodeposition and its comparison with anodically deposited GO. This coating was comprehensively characterized using Fourier-transform infrared (FTIR), X-ray diffraction (XRD), Raman spectroscopy, Field emission scanning electron microscopy (FE-SEM) coupled with Energy-dispersive X-ray spectroscopy (EDAX). Subsequently, its corrosion resistance for MS1010 mild steel in 3.5 wt % (NaCl) was evaluated via weight loss, contact angle, electrochemical impedance spectroscopy (EIS), Potentiodynamic polarization, and surface analysis techniques. These observations suggest that graphene oxide-zinc oxide (GO-ZnO) adsorbs nickel onto the MS surface effectively and reduces defects, which helps in blocking active corrosion sites. Tafel plots and EIS revealed that the Ni-GO-ZnO coating exhibited the lowest current density (39.95 µAcm²) and the highest charge transfer resistance (1211 Ωcm²). This was further validated by long-term immersion testing, where the Ni-GO-ZnO coating exhibited significantly less weight loss (1.33 mils/Y) compared to the deposited GO coating (2.2 mils/Y). The mechanism of formation of deposited GO and Ni-GO-ZnO coating on the metallic surface is proposed. The enhanced corrosion resistance of the Ni-GO-ZnO coating is attributed to its ability to 1) form a more compact metallic layer and 2) Minimize the active surface area vulnerable to corrosion attack. 3) Diminishes the presence of holes and cracks for corrosive ion ingress.4) Functionally impedes the ingress of chloride ions, primarily liable for steel degradation. The synergistic effect of the GO-ZnO constituents within the nickel matrix significantly enhances the long-term durability and integrity of the protective layer, a phenomenon hitherto unexplored. The empirical outcomes advocate for the advanced application of GO-ZnO-nickel coatings in safeguarding infrastructural materials against corrosive degradation.

Conserved proline residues prevent dimerization and aggregation in the β-lactamase BlaC.

Evolution leads to conservation of amino acid residues in protein families. Conserved proline residues are usually considered to ensure the correct folding and to stabilize the three-dimensional structure. Surprisingly, proline residues that are highly conserved in class A β-lactamases were found to tolerate various substitutions without large losses in enzyme activity. We investigated the roles of three conserved prolines at positions 107, 226, and 258 in the β-lactamase BlaC from Mycobacterium tuberculosis and found that mutations can lead to dimerization of the enzyme and an overall less stable protein that is prone to aggregate over time. For the variant Pro107Thr, the crystal structure shows dimer formation resembling domain swapping. It is concluded that the proline substitutions loosen the structure, enhancing multimerization. Even though the enzyme does not lose its properties without the conserved proline residues, the prolines ensure the long-term structural integrity of the enzyme.

Modelling of macrophage responses to biomaterials in vitro: state-of-the-art and the need for the improvement.

The increasing use of medical implants in various areas of medicine, particularly in orthopedic surgery, oncology, cardiology and dentistry, displayed the limitations in long-term integration of available biomaterials. The effective functioning and successful integration of implants requires not only technical excellence of materials but also consideration of the dynamics of biomaterial interaction with the immune system throughout the entire duration of implant use. The acute as well as long-term decisions about the efficiency of implant integration are done by local resident tissue macrophages and monocyte-derived macrophages that start to be recruited during tissue damage, when implant is installed, and are continuously recruited during the healing phase. Our review summarized the knowledge about the currently used macrophages-based in vitro cells system that include murine and human cells lines and primary ex vivo differentiated macrophages. We provided the information about most frequently examined biomarkers for acute inflammation, chronic inflammation, foreign body response and fibrosis, indicating the benefits and limitations of the model systems. Particular attention is given to the scavenging function of macrophages that controls dynamic composition of peri-implant microenvironment and ensures timely clearance of microorganisms, cytokines, metabolites, extracellular matrix components, dying cells as well as implant debris. We outline the perspective for the application of 3D systems for modelling implant interaction with the immune system in human tissue-specific microenvironment avoiding animal experimentation.

A first assessment of Hong Kong's circular economy for wastepaper: Material flows, value chains and the role of the semi-formal informal recycling sector

Collection, as the first stage of the recycling process, and pre-processing to increase waste stream purity constitute key operations for achieving high recycling rates and a closed loop in the circular economy. For wastepaper recycling in Hong Kong, it is the semi-formal-informal recycling (SFIR) sector that plays a central role in both stages. This study analyses the so far little explored SFIR stakeholder network in Hong Kong and sheds light on value chains, recovered waste paper quantities and the impact of policies on the sector. The findings show that SFIR stakeholders reclaim 55.6 t/recycling station/month of wastepaper and thereby achieve about a 5.7 times higher reclaim rate than the formal-private recycling system. Critical to this achievement is the SFIR transaction network, which enables its stakeholders to develop a value chain and thereby generate an added value of around 1900 HKD (243.9 USD/t) for wastepaper. Given limited circular structures in Hong Kong, financial subsidies are critical to sustain the SFIR's operations over the short-term. However, over the long-term legalization and integration of its stakeholders are necessary to ensure an economically and socially sustainable wastepaper recovery system in Hong Kong.

Analisis Integrasi Pasar Parsial untuk Komoditas Daging Ayam Broiler antar Berbagai Kabupaten/Kota di Provinsi Jambi

This research aims to determine the spatial market integration of broiler chicken meat commodities between various districts/cities in Jambi Province. The analysis method used is the VAR (Vector Autoregression) / VECM (Vector Error Correction Model) model. There is partial market integration in the long and short term for broiler chicken meat commodities between various regencies/cities in Jambi Province so that the price of broiler chicken meat in regencies/cities in Jambi Province influences each other not only in the current period but in relation to prices 1 to 2 days before. There is short and long-term spatial market integration for broiler chicken meat in districts/cities in Jambi Province. The price of broiler chicken meat in Jambi City causes changes in the price of broiler chicken meat in Batang Hari Regency, Kerinci Regency, Merangin Regency and West Tanjung Jabung Regency, and vice versa.

Assimilation of the deep learning-corrected global forecast system fields into the regional model for improving medium-range persistent precipitation forecasts

The error of regional models gradually increases during long-term integration, and it can be reduced with the constraint of large-scale circulation by assimilating global forecast system (GFS) fields to improve the forecast performance. However, with increasing forecast time, the GFS forecast error also significantly increases and varies widely. Directly assimilating GFS fields into the regional model without processing may generate negative impacts, whereas employing postprocessing correction methods can effectively mitigate GFS forecast errors. In this study, the GFS data of European Centre for Medium-Range Weather Forecasts (ECMWF) are first corrected using a convolutional long- and short-term memory network method. The correction model can correct multiple forecasts simultaneously by training only one model, and the correction results are less erroneous than those obtained by training multiple correction models for the different forecast times and pressure layers. The corrected ECMWF forecast fields are then assimilated into Weather Research and Forecasting Model (WRF) using the nudging method. This assimilation method generally improves the forecasts for precipitation above the moderate rainfall level at forecast times of 4–7 days, and reduces the errors of surface wind speed forecasts. This study improves the accuracy of correction models and the forecasts of persistent precipitation weather event with regional model.

Promoting Eco-Friendly Consumption Behavior in Vocational High School Students: A Comprehensive Case Study of Educational Approaches

Background: Students can be taught eco-friendly consuming habits through classroom learning activities with the help of teachers and other school-related activities. The study's focus is a case study completed at a vocational high school. We seek to understand the broad-reaching consequences that this teaching strategy might evoke by examining the potential implications of integrating environmentally responsible consumption practices within an educational framework. Through a thorough case study, we aim to shed light on how incorporating environmentally responsible consuming practices into schooling could support more general educational goals and encourage sustainable habits. Internalizing this through character education entails setting models and developing routine behaviors based on school policies and extracurricular activities in addition to integrated environmental education. This supports the long-term integration of these ideals into students' personalities. Method: This research uses a survey methodology and is explanatory. The SPSS (Statistical Package for Social Science) was used to analyze the data. 95 respondents make up the sample size for the sampling method, which uses proportionate random sampling. Result: According to the research's findings, integrating character education and general education are impacted by internalizing environmentally responsible consumption habits.

Assessing Uganda’s Progressive Refugee Policy in the Era of COVID-19: Introduction to the Special Issue

Uganda is home to 1.5 million refugees from DRC, Burundi, South Sudan and other countries. The Uganda political framework is one of the most progressive and inclusive toward refugees. Only a fraction of the refugees is likely to revert to their home countries. The papers collected in this special issue assess Uganda’s progressive refugee policy with reference to how it functioned in the era of COVID-19 using a unique panel data collected between 2017 and 2021. The findings of the special issue stress that the support to refugees and hosts is helping to manage daily challenges but not to ultimately get them out of poverty. Further, this support was insufficient to provide a comprehensive response to COVID-19. For the long-term sustainable integration and development, new policy approaches are needed.

Blue-Green Horizons: Redefining Alginate Bioplastics with Spirulina Dyes

AbstractThis study introduces a novel, eco-friendly approach for the extraction and application of Spirulina (Sp.) pigments in alginate bioplastics, representing a significant advancement over traditional dyeing methods. The research explores a zero waste model process in a Fab Lab setting, involving three stages, liquid dye preparation, fibre dyeing, and bioplastic dyeing, with a focus on utilizing all by-products sustainably. In the liquid dye preparation phase, vibrant blue-green pigments were successfully extracted from Spirulina powder. The colour depth depended on the Spirulina concentration and the precipitation method used, with pH playing a critical role in achieving a range of green–blue hues. The fibre dyeing phase tested Spirulina dyes on various natural fibres, examining the impact of alum mordant pre-treatment on colour absorption and stability. Optimal dyeing results were obtained with a 1:1 ratio of Spirulina-filtered powder suspension to alum acid precipitation solution at a pH of 4. The techniques optimized were then applied to alginate bioplastics, including bio-yarns and bio-films, yielding a wide spectrum from green to blue. Bio-yarns showed better colour retention compared to bio-films, possibly due to residual alum. However, challenges in long-term colour stability and structural integrity against environmental factors like oxidation and humidity were observed. The study contributes valuable insights into the application of natural dyes in bioplastics, particularly in achieving blue and green shades with a Spirulina zero waste model. This work is significant for future sustainable material science research and emphasizes the importance of balancing aesthetic, functional, and environmental factors in circular design. Graphical Abstract

An approach for assessment of CO2 leakage using mechanistic modelling: CO2 injection in deep saline aquifer of Lithuanian basin in presence of fault and fractures

Injecting CO2 into deep saline aquifers is a prominent strategy for carbon capture and storage (CCS) to mitigate greenhouse gas emissions. However, ensuring the long-term integrity of CO2 storage is crucial to prevent leakage and potential environmental hazards. This paper investigates the impact of presence of faults and fracture on CO2 leakage volumes. Particular case of CO2 injection into a deep saline aquifer for carbon capture and storage (CCS) applications is investigated. This paper explores the relationship between fracture permeability and the potential for CO2 leakage.

A soft, scalable and adaptable multi-contact cuff electrode for targeted peripheral nerve modulation

BackgroundCuff electrodes target various nerves throughout the body, providing neuromodulation therapies for motor, sensory, or autonomic disorders. However, when using standard, thick silicone cuffs, fabricated in discrete circular sizes, complications may arise, namely cuff displacement or nerve compression, due to a poor adaptability to variable nerve shapes and sizes encountered in vivo. Improvements in cuff design, materials, closing mechanism and surgical approach are necessary to overcome these issues.MethodsIn this work, we propose a microfabricated multi-channel silicone-based soft cuff electrode with a novel easy-to-implant and size-adaptable design and evaluate a number of essential features such as nerve-cuff contact, nerve compression, cuff locking stability, long-term integration and stimulation selectivity. We also compared performance to that of standard fixed-size cuffs.ResultsThe belt-like cuff made of 150 μm thick silicone membranes provides a stable and pressure-free conformal contact, independently of nerve size variability, combined with a straightforward implantation procedure. The adaptable design and use of soft materials lead to limited scarring and demyelination after 6-week implantation. In addition, multi-contact designs, ranging from 6 to 16 electrodes, allow for selective stimulation in models of rat and pig sciatic nerve, achieving targeted activation of up to 5 hindlimb muscles.ConclusionThese results suggest a promising alternative to classic fixed-diameter cuffs and may facilitate the adoption of soft, adaptable cuffs in clinical settings.