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Abstract In the last ten years, stem cell (SC) therapy has been extensively used to treat a range of conditions such as degenerative illnesses, ischemia-related organ dysfunction, diabetes, and neurological disorders. However, the clinical application of these therapies is limited due to the poor survival and differentiation potential of stem cells (SCs). Extracorporeal shock wave therapy (ESWT), as a non-invasive therapy, has shown great application potential in enhancing the proliferation, differentiation, migration, and recruitment of stem cells, offering new possibilities for utilizing ESWT in conjunction with stem cells for the treatment of different systemic conditions. The review provides a detailed overview of the advances in using ESWT with SCs to treat musculoskeletal, cardiovascular, genitourinary, and nervous system conditions, suggesting that ESWT is a promising strategy for enhancing the efficacy of SC therapy for various diseases.

Designing hydrogen-resistant Ni-based alloys from the perspective of the Ni/graphene interface (NGI) provides the potential to increase hydrogen trapping away from potential fracture paths. Nonetheless, numerous essential mechanisms of hydrogen penetration behaviors in the Ni-graphene nanocomposites are presently not well understood. Here we investigate the influence of Ni/graphene interfaces (NGIs) on the behavior of hydrogen diffusion and trapping in their vicinity using atomistic simulations. Hydrogen diffusion is competitively affected by elevated temperatures and NGIs. The difference in the mean square displacement for hydrogen between the composites and pure Ni can be of two orders of magnitude, highlighting the sluggish diffusion in the composites. As NGIs reduce hydrogen formation energy and diffusion barrier, hydrogen prefers to migrate towards the interfaces. Hydrogen readily forms sp3 C–H bonds with C atoms, thereby impeding its detachment from graphene and subsequent entry into a non-diffusible state. Results of the study will contribute to the use of Ni–graphene nanocomposites as hydrogen-resistant materials for nuclear reactors.

Manganese pollution in surface water has been a new concern in decentralized drinking water treatment. The dissolved manganese cannot be effectively removed by the traditional ultrafiltration (UF) process, but will cause severe membrane fouling. To address such issues, an innovative gravity-driven membrane (GDM) coupled with a dynamic manganese oxide (MnOx) film on the membrane surface was proposed, with hopes of enhancing manganese removal and alleviating membrane fouling. The results demonstrated that pre-coating a dynamic MnOx film on the membrane surface of a GDM system would effectively reduce start-up time for removing iron and manganese pollutants, without affecting the flux stabilization of the GDM. Effective manganese removal (~80%) primarily depended on the adsorption and auto-catalytic oxidation facilitated by the pre-coating of MnOx. Furthermore, the MnOx film notably enhanced organic pollutant removal efficiency. Additionally, the MnOx coated on the membrane surface acted as a skeleton, promoting the gradual formation of a biocake layer with a heterogeneous and porous structure, which benefited the flux stabilization of the GDM. In particular, the fine and homogeneous MnOx-M derived from the backflushing water of the mature manganese sand filter exhibited precise and uniform coating on the membrane surface, effectively mitigating the irreversible pore plugging caused by organic matter penetration and thereby enhancing stable flux by ~16.3% compared to the control. This study offered a novel strategy to enhance the purification efficiency of GDM system treating manganese pollution and was expected to contribute to the technological advancement of decentralized water supply scenarios.

Direct ultrafiltration (UF) is anticipated to be a promising technology for rural water supply due to its stable permeate quality and ease of automatic operation & maintenance. However, seasonal high turbidity in the surface water resources caused severe membrane fouling, resulting in the requirement of frequent cleaning of the UF process, and limiting the broad application of the direct UF in treating rural surface water. To address this issue, this study investigated the feasibility and mechanism of in situ aeration in alleviating the UF membrane fouling in treating surface water with high turbidity (200, 500, and 800 NTU). The results indicated that with the weak aeration (0.4 m3/(m2·min)), the concentration of polysaccharides accumulated on the membrane surface was high, and serious membrane fouling was observed. With medium aeration (0.8 and 1.2 m3/(m2·min)), bubble shear force could effectively reduce the foulants accumulated on the membrane surface to alleviate the membrane fouling. During the whole experiment, the optimal group (1.2 m3/(m2·min)) showed a 45% lower TMP compared to the control. However, strong aeration (1.6 m3/(m2·min)) caused floc breakage and was less conducive to the membrane fouling control compared to the medium aeration. Furthermore, under in situ aeration, the contents of polysaccharide accumulated on the membrane surface and deposited in the membrane pores were reduced by 8.85%~49.29%, and the structures of the cake layer turned out to be porous and permeable, implying that in situ aeration could significantly modify the structure and composition of the cake layer, contributing to the UF membrane fouling control in treating the seasonal high-turbidity surface water. These findings will provide novel approaches for the application of UF technology in rural water supply.

Online identification of aerodynamic parameters of experimental rockets was completed based on unscented Kalman filtering (UKF). Numerical simulation, hardware-in-the-loop (HIL) simulation, and flight tests were conducted. The identification error of aerodynamic force in numerical simulation and HIL simulation is within 2%. For flight test data, trajectory reconstruction was performed using the identified aerodynamic forces, and the results showed that the identification results were more accurate than the interpolation table calculation results. The flight test identification results show that the identification method can complete parameter online identification under the conditions of limited performance of onboard computers, real sensor errors, and servo response. The approximate linear correlation between α and δe and the reason for their formation from the moment balance were analyzed. It was pointed out that when the recognition sampling period is long, this phenomenon will affect the identification of parameters, and a solution is proposed.

Thermoelectric (TE) materials working in radioisotope thermoelectric generators are irradiated by neutrons throughout its service; thus, investigating the neutron irradiation stability of TE devices is necessary. Herein, the influence of neutron irradiation with fluences of 4.56 × 1010 and 1 × 1013 n/cm2 by pulsed neutron reactor on the electrical and thermal transport properties of n-type Bi2Te2.7Se0.3 and p-type Bi0.5Sb1.5Te3 thermoelectric alloys prepared by cold-pressing and molding is investigated. After neutron irradiation, the properties of thermoelectric materials fluctuate, which is related to the material type and irradiation fluence. Different from p-type thermoelectric materials, neutron irradiation has a positive effect on n-type Bi2Te2.7Se0.3 materials. This result might be due to the increase of carrier mobility and the optimization of electrical conductivity. Afterward, the effects of p-type and n-type TE devices with different treatments on the output performance of TE devices are further discussed. The positive and negative effects caused by irradiation can cancel each other to a certain extent. For TE devices paired with p-type Bi0.5Sb1.5Te3 and n-type Bi2Te2.7Se0.3 thermoelectric legs, the generated power and conversion efficiency are stable after neutron irradiation.

Fiber-reinforced polymer (FRP) composites are considered suitable candidates for structural materials of spacecrafts due to their excellent properties of high strength, light weight, and corrosion resistance. An online health monitoring method for FRP composites must be applied to space structures. However, the application of existing health monitoring methods to space structures is limited due to the harsh space environment. Here, carbon fiber-reinforced polymer (CFRP) composites embedded with fiber Bragg grating (FBG) sensors were prepared to explore the feasibility of strain monitoring using embedded FBG sensors in γ-radiation environment. The analysis of the influence of radiation on the strain monitoring demonstrated that the embedded FBG can be successfully applied to the health monitoring of FRP composites in radiation environment.

Space nuclear reactors are becoming popular in deep space exploration owing to their advantages of high-power density and stability. Following the fourth-generation nuclear reactor technology, a conceptual design of the dual drum-controlled space molten salt reactor (D2-SMSR) is proposed. The reactor concept uses molten salt as fuel and heat pipes for cooling. A new reactivity control strategy that combines control drums and safety drums was adopted. Critical physical characteristics such as neutron energy spectrum, neutron flux distribution, power distribution and burnup depth were calculated. Flow and heat transfer characteristics such as natural convection, velocity and temperature distribution of the D2-SMSR under low gravity conditions were analyzed. The reactivity control effect of the dual-drums strategy was evaluated. Results showed that the D2-SMSR with a fast spectrum could operate for 10 years at the full power of 40 kWth. The D2-SMSR has a high heat transfer coefficient between molten salt and heat pipe, which means that the core has a good heat-exchange performance. The new reactivity control strategy can achieve shutdown with one safety drum or three control drums, ensuring high-security standards. The present study can provide a theoretical reference for the design of space nuclear reactors.

This study proposes an improved color correction algorithm based on Fuzzy c-means (FCM) clustering algorithm and Wallis filtering to address the problem of spectral drift in image stitching. The proposed method can be applied to general multi-hyperspectral remote sensing images and focuses on color correction processing of images with and without overlapping areas. To ensure color correction, the color gamut is transformed using the color gamut transformation method, and an improved color matching algorithm based on Wallis filtering is used. For non-overlapping areas or hyperspectral remote sensing images, a feature class matching relationship is established using the class matching as the overlapping area for color correction processing, inspired by the application of FCM clustering in image segmentation. The experimental results show that the improvement of the histogram matching algorithm using Wallis filtering achieves a performance improvement of about 9.3%, and this performance is indexed by the spectral distortion. Also, the average gradient value of the image to be homogenized was significantly improved in the image color correction task without overlapping regions, where the false color image improvement was about 27.2%. The proposed approach is time-efficient and robust, while ensuring the quality of color correction processing.

Radioluminescent isotope cells (RLICs) have the advantages of a long lifetime and high stability due to the use of phosphor material with excellent radiation resistance. Current research efforts mainly focus on the improvement of energy conversion efficiency. This study presents a 63Ni-based RLIC with enhanced photon transport interfaces. The ZnS:Cu phosphor layer is spin-coated directly onto the surface of an AlGaInP-based photovoltaic cell (PC) to achieve efficient coupling of photons by optimizing the transmission interface, and a metal film is sputtered onto the ZnS:Cu layer to reflect radioluminescence towards the PC. Theoretical simulations and experiments are used to compare and validate the integration designs of the ZnS:Cu layer and metal reflective films (Ag, Al, and Ni). It is demonstrated that the RLIC based on the spin-coated ZnS:Cu/PC structure with a 100 nm thick Ag film can increase the output power by 52.6%, compared to conventional RLICs based on adhesive ZnS:Cu/BOPP/PC structure. Maximum efficiency of 0.92% is expected under beta radiation of 63Ni. The enhancement of photon transport is attributed to fluorescence backward reflection and refractive index matching at the interfaces.

Ultrafiltration (UF) has been increasingly implemented in drinking water treatment plants; however, algae and their secretions can cause severe membrane fouling and pose great challenges to UF in practice. In this study, a simple and practical chemically enhanced backwashing (CEB) process was developed to address such issues using various cleaning reagents, including sodium hypochlorite (NaClO), sodium chloride (NaCl), sodium hydroxide (NaOH), sodium citrate, and their combinations. The results indicate that the type of chemical played a fundamental role in alleviating the hydraulically irreversible membrane fouling (HIMF), with NaClO as the best-performing reagent, followed by NaCl. Furthermore, a CEB process using a combination of NaClO with NaCl, NaOH, or sodium citrate delivered little improvement in the alleviation of membrane fouling compared with NaClO alone. The optimized dosage and dosing frequency of NaClO were 10 mg·L−1 two times per day. Long-term pilot-scale and full-scale experiments further verified the feasibility of the CEB process in relieving algae-derived membrane fouling. Compared with the conventional hydraulic backwashing without chemical involvement, the CEB process can effectively remove the organic foulants including biopolymers, humic substances, and protein-like substances by means of oxidization, thereby weakening the cohesive forces between the organic foulants and the membrane surface. Therefore, the CEB process can efficiently alleviate the algae-related membrane fouling with lower chemical consumption, and is proposed as an alternative to control membrane fouling in treating the algae-containing surface water.

Nonlinear dynamic of a flexible slender truss-structure mounted manipulator for on-orbit assembly, which can be simplified as a beam–rotating link interaction system, is theoretically investigated. The governing partial differential equations (PDEs) of beam with time-varying coefficients is established by using the D’Alembert principle incorporated with the moment balance method where the beam is of a Euler–Bernoulli type and the influence of slope is considered. Such system is a typical parametrically excited system. The multiple scales method is used to determine the approximate solution and the conditions of the primary resonance ( $\omega _{1}\approx \omega _{ref}$ ) and sub-harmonic resonance ( $\omega _{1}\approx ~2\omega _{ref}$ , $\omega _{1}\approx ~3\omega _{ref}$ and $\omega _{1}\approx ~4\omega _{ref}$ ) are obtained. In addition, the nonlinear response, stability and bifurcations for primary and sub-harmonic resonance conditions have also been investigated by varying system parameters. Moreover, the results of some specific conditions by the perturbation analysis are compared with the numerical solution and are found to be in good agreement. This work has certain guiding significance for autonomous on-orbit assembly task and the method can be extended to the more general three-dimensional case.

The AISI 316L austenitic stainless steel fabricated by selective laser melting (SLM) is considered to have great prospects for applications in nuclear systems. This study investigated the He-irradiation response of SLM 316L, and several possible reasons for the improved He-irradiation resistance of SLM 316L were systematically revealed and evaluated by using TEM and related techniques. The results show that the effects of unique sub-grain boundaries have primary contributions to the decreased bubble diameter in SLM 316L compared to that in the conventional 316L counterpart, while the effects of oxide particles on bubble growth are not the dominant factor in this study. Moreover, the He densities inside the bubbles were carefully measured using electron energy loss spectroscopy (EELS). The mechanism of stress-dominated He densities in bubbles was validated, and the corresponding reasons for the decrease in bubble diameter were freshly proposed in SLM 316L. These insights help to shed light on the evolution of He bubbles and contribute to the ongoing development of the steels fabricated by SLM for advanced nuclear applications.

The 316L stainless steels (SS) have become one of the most common structural materials in nuclear system applications due to their excellent physicochemical performance. Selective laser melting (SLM) preparation, mechanical properties, and irradiation resistance of 316L SS reinforced by second-phase particles have aroused extensive attention. Here, the mechanical properties of 316L SS with different LaB6 contents processed by SLM before irradiation and the irradiation-induced swelling after 50 keV He+ irradiation at room temperature were investigated. Results showed that the microstructure was refined with the LaB6 addition, and the size of 316L SS subgrains decreased with the increase of LaB6. LaB6 reinforced 316L SS (316L-LaB6) exhibited higher hardness and yield strength compared with 316L SS without LaB6 addition. After 50 keV He+ irradiation, the irradiation-induced swelling rate of 316L-LaB6 was lower than that of 316L SS without LaB6 addition, indicating that LaB6 improved the irradiation resistance of 316L SS. Consequently, our study indicated the potential of using 316L-LaB6 as irradiation-resistant material.

Accurate localization of radioactive materials is crucial in homeland security and radiological emergencies. Coded-aperture gamma camera is an interesting solution for such applications and can be developed into portable real-time imaging devices. However, traditional reconstruction methods cannot effectively deal with signal-independent noise, thereby hindering low-noise real-time imaging. In this study, a novel reconstruction method with excellent noise-suppression capability based on a multi-layer perceptron (MLP) is proposed. A coded-aperture gamma camera based on pixel detector and coded-aperture mask was constructed, and the process of radioactive source imaging was simulated. Results showed that the MLP method performs better in noise suppression than the traditional correlation analysis method. When the Co-57 source with an activity of 1 MBq was at 289 different positions within the field of view which correspond to 289 different pixels in the reconstructed image, the average contrast-to-noise ratio (CNR) obtained by the MLP method was 21.82, whereas that obtained by the correlation analysis method was 5.85. The variance in CNR of the MLP method is larger than that of correlation analysis, which means the MLP method has some instability in certain conditions.

Environmental pollution has become one of the most urgent global issues that we have to face now. Searching new technologies to solve environmental issues is of great significance. By intimately coupling photocatalytic materials with microbes, the emerging photocatalytic material–microbe hybrid (PMH) system takes advantages of the high-efficiency, broad-spectrum light capture capability of the photocatalytic material and the selectivity of microbial enzymatic catalysis to efficiently convert solar energy into chemical energy. The PMH system is originally applied for the solar-to-chemical production. Interestingly, recent studies demonstrate that this system also has great potential in treating environmental contaminations. The photogenerated electrons produced by the PMH system can reductively decompose organic pollutants with oxidative nature (e.g., refractory azo dyes) under anaerobic circumstances. Moreover, based on the redox reactions occurring on the surface of photocatalysts and the enzymatic reactions in microbes, the PMH system can convert the valences of multiple heavy metal ions into less toxic or even nontoxic status simultaneously. In this review, we introduce the recent advances of using the PMH system in treating environmental pollutions and compare this system with another similar system, the traditional intimately coupled photocatalysis and biodegradation (ICPB) system. Finally, the current challenges and future directions in this field are discussed as well.

The keywords used in traditional stock price prediction are mainly based on literature and experience. This study designs a new text mining method for keywords augmentation based on natural language processing models including Bidirectional Encoder Representation from Transformers (BERT) and Neural Contextualized Representation for Chinese Language Understanding (NEZHA) natural language processing models. The BERT vectorization and the NEZHA keyword discrimination models extend the seed keywords from two dimensions of similarity and importance, respectively, thus constructing the keyword thesaurus for stock price prediction. Furthermore, the predictive ability of seed words and our generated words are compared by the LSTM model, taking the CSI 300 as an example. The result shows that, compared with seed keywords, the search indexes of extracted words have higher correlations with CSI 300 and can improve its forecasting performance. Therefore, the keywords augmentation model designed in this study is helpful to provide references for other variable expansion in financial time series forecasting.

Background: Myocardial perfusion imaging modalities, such as cardiac magnetic resonance (CMR), single-photon emission computed tomography (SPECT), and positron emission tomography (PET), are well-established non-invasive diagnostic methods to detect hemodynamically significant coronary artery disease (CAD). The aim of this meta-analysis is to compare CMR, SPECT, and PET in the diagnosis of CAD and to provide evidence for further research and clinical decision-making.Methods: PubMed, Web of Science, EMBASE, and Cochrane Library were searched. Studies that used CMR, SPECT, and/or PET for the diagnosis of CAD were included. Pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio with their respective 95% confidence interval, and the area under the summary receiver operating characteristic (SROC) curve were calculated.Results: A total of 203 articles were identified for inclusion in this meta-analysis. The pooled sensitivity values of CMR, SPECT, and PET were 0.86, 0.83, and 0.85, respectively. Their respective overall specificity values were 0.83, 0.77, and 0.86. Results in subgroup analysis of the performance of SPECT with 201Tl showed the highest pooled sensitivity [0.85 (0.82, 0.88)] and specificity [0.80 (0.75, 0.83)]. 99mTc-tetrofosmin had the lowest sensitivity [0.76 (0.67, 0.82)]. In the subgroup analysis of PET tracers, results indicated that 13N had the lowest pooled sensitivity [0.83 (0.74, 0.89)], and the specificity was the highest [0.91 (0.81, 0.96)].Conclusion: Our meta-analysis indicates that CMR and PET present better diagnostic performance for the detection of CAD as compared with SPECT.

Gravity-driven membrane (GDM) filtration technology has been extensively in the employed drinking water treatment, however, the effect filtration mode (i.e., dead-end mode vs. cross-flow mode) on its long-term performance has not been systematically investigated. In this study, pilot-scale GDM systems were operated using two submerged filtration mode (SGDM) and cross-flow mode (CGDM) at the gravity-driven pressures 120 mbar and 200 mbar, respectively. The results showed that flux stabilization was observed both in the SGDM and CGDM during long-term filtration, and importantly the stabilized flux level of CGDM was elevated by 3.5–67.5%, which indicated that the filtration mode would not influence the occurrence of flux stability, but significantly improve the stable flux level. Interestingly, the stable flux level was not significantly improved with the increase of driven pressure, and the optimized driven pressure was 120 mbar. In addition, the GDM process conferred effective removals of turbidity, UV254, CODMn, and DOC, with average removals of 99%, 43%, 41%, and 20%, respectively. With the assistance of cross flow to avert the overaccumulation of contaminants on the membrane surface, CGDM process exhibited even higher removal efficiency than SGDM process. Furthermore, it can be found that the CGDM system can effectively remove the fluorescent protein-like substances, and the intensities of tryptophans substance and soluble microbial products were reduced by 64.61% and 55.08%, respectively, higher than that of the SGDM. Therefore, it can be determined that the filtration mode played an important role in the flux stabilization of GDM system during long-term filtration, and the cross-flow filtration mode can simultaneously improve the stabilized flux level and removal performance.

Biological activated carbon (BAC) biofilter coupling ultrafiltration (UF) is a promising process for the treatment of river water contaminated by pharmaceutical and personal care products (PPCPs). However, the pilot-scale study should be conducted to reveal the long-term removal performance and the respective contributions of BAC and UF. In this study, a BAC-UF system with treatment capacity of 0.16 m3 h−1 was operated for 130 days. The water quality was analyzed in terms of CODMn, UV254, NH4+-N, and PPCPs. The results showed that both BAC and UF were related to the removal of organic matter (CODMn and UV254), achieving the removals of 56.00% and 55.25%, respectively. Similarly, BAC and UF were both relevant to the removal effects of ammonia nitrogen, nitrite, and nitrate. Moreover, the BAC-UF process was featured with a high efficiency in the removal of PPCPs, and the average removal of total PPCPs reached 47.84%, especially anhydroerythromycin, sulfachloropyridazine, sulfadiazine, trimethoprim, and caffeine. Besides, it was found that the BAC unit played a key role in PPCPs removal and the UF unit also degraded them by the biomass on UF membranes. Therefore, this study proved the removal performance of BAC-UF for treating popular pollutants from river water, and the BAC-UF process in this work can be considered as a feasible method of producing clean drinking water.

Atomistic simulations were utilized to investigate the effects of interstitial carbon on the radiation tolerance of carbon-doped NiFe binary alloy (NiFeC). Cascade simulation and defect insertion method were implemented to systematically study the radiation-induced defect generation and clustering mechanisms. Results showed that the interstitial carbon reduced the defect counts during the thermal spike expansion in the ballistic stage. For the final survived defect clusters, the cluster size in NiFeC decreased significantly relative to that in NiFe alloy. The energetic and kinetic calculations verified the migration behavior of the interstitial and vacancy in NiFeC. The mobility of the interstitial was inhibited by the lattice distortion aggravated by interstitial carbon. The vacancy tended to bind with the carbon atoms and remained immobile. Both characteristics suppressed the formation of large-sized clusters, such as dislocation loop and stacking fault tetrahedra observed in NiFe.

With a highly functional methyl vinyl silicone rubber (VMQ) matrix and filler materials of B4C, PbO, and benzophenone (BP) and through powder surface modification, silicone rubber mixing, and vulcanized molding, a flexible radiation shielding and resistant composite was prepared in the study. The dispersion property of the powder in the matrix filler was improved by powder surface modification. BP was added into the matrix to enhance the radiation resistance performance of the composites. After irradiation, the tensile strength, elongation, and tear strength of the composites decreased, while the Shore hardness of the composites and the crosslinking density of the VMQ matrix increased. Moreover, the composites with BP showed better mechanical properties and smaller crosslinking density than those without BP after irradiation. The initial degradation temperatures of the composites containing BP before and after irradiation were 323.6°C and 335.3°C, respectively. The transmission of neutrons for a 2-mm thick sample was only 0.12 for an Am–Be neutron source. The transmission of γ-rays with energies of 0.662, 1.173, and 1.332 MeV for 2-cm thick samples were 0.7, 0.782, and 0.795, respectively. Keywords: Flexible Composite, Neutron Shielding, Radiation Resistance, γ-ray Shielding

In this study, fast-curing shielding materials were prepared with a two-component polyurethane matrix and a filler material of PbO through a one-step, laboratory-scale method. With an increase in the filler content, viscosity increased. However, the two components showed a small difference. Curing time decreased as the filler content increased. The minimum tack-free time of 27 s was obtained at a filler content of 70 wt%. Tensile strength and compressive strength initially increased and then decreased as the filler content increased. Even when the filler content reached 60 wt%, mechanical properties were still greater than those of the matrix. Cohesional strength decreased as the filler content increased. However, cohesional strength was still greater than 100 kPa at a filler content of 60 wt%. The γ-ray-shielding properties increased with the increase in the filler content, and composite thickness could be increased to improve the shielding performance when the energy of γ-rays was high. When the filler content was 60 wt%, the composite showed excellent comprehensive properties.

In recent times, higher education has seen a growing concern regarding the utilisation of artificial intelligence, especially with the emergence of ChatGPT. This technology can generate written content and respond to queries at a level that is nearly indistinguishable from a human writer. This feature has drawn substantial interest from students in higher education and has led to concern that students will use ChatGPT's capabilities to cheat on written formative and summative assessments. In this paper, we will review the usage of ChatGPT in higher education assessments and investigate why students want to cheat using artificial intelligence capabilities. It also offers a critical perspective on the challenges associated with detecting ChatGPTgenerated content and its impact on academic integrity. We also consider whether artificial intelligence provides more opportunities for academics to focus on assessing higherorder thinking and strategies. [ABSTRACT FROM AUTHOR]

Contract cheating has become increasingly an issue as universities adapt to online and hybrid teaching, learning, and assessments. Due to the COVID-19 pandemic, higher education institutions began to administer examinations more frequently online, and it led to the emergence of websites and commercial service providers who offer contract cheating services globally. In this paper, we examine the key elements that lead students to turn to contract cheating as well as the elements that deter the students from engaging in such unethical behaviour. We also investigate how assessment design can encourage authentic learning, although assessment design alone cannot eliminate contract cheating. The effects of contract cheating on academic standards and quality assurance are also examined. Mainly the study results show that the act of contract cheating is a result of interrelated internal and external factors in an individual. Although a number of measures, including authentic evaluations and digital tools, have been implemented to discourage students from cheating, no strategy is strong enough to control the issue permanently. Hence, academic integrity is still not assured, highlighting the necessity of a global movement to solve the problem. [ABSTRACT FROM AUTHOR]