This rapid systematic review synthesizes emerging evidence on the impact of Nigeria’s 2023 dual economic reforms, fuel subsidy removal, and foreign exchange harmonization on Small and Medium Enterprises (SMEs). Employing a PRISMA-guided methodology, we analyzed 32 academic, institutional, and industry studies from 2015 to 2025. The findings reveal that the reforms have triggered hyperinflation, soaring operational costs, foreign exchange scarcity, and prohibitive borrowing rates, severely undermining SME profitability, production capacity, and survival rates. Sectoral analysis indicates disproportionate impacts on import-dependent manufacturing SMEs, while technology and service-oriented enterprises exhibit greater resilience. Despite short-term disruptions, the reforms also present long-term opportunities for efficiency, innovation, and foreign investment. The study proposes an integrated theoretical framework combining institutional theory, resource-based view, and Schumpeterian creative destruction to explain differential firm-level outcomes. It was concluded that evidence-based policy recommendations, including targeted FX windows, credit guarantees, digital grants, and localization support, are needed to mitigate adverse effects and foster SME sustainability in Nigeria’s evolving macroeconomic landscape.
Ruminto Subekti, Ismail Rokhim, Muhammad Sulaeman Gheofani Gheofani
Travel, tourism and hospitality companies have started to adopt RAISA systems in the form of chatbots, delivery robots, autonomous dishwashers, conveyor restaurants, self-service information kiosks and many others [1], [2]. This research focuses on the implementation of deep learning artificial neural networks for object recognition in determining the pose estimation of the manipulator robot and planning the grip on the end effector. A robotic manipulator with 4 degrees of freedom is used to support the estimation of pose angles and an end effector in the form of a 5-finger gripper is used to obtain various grips on objects with random shapes. An RGB camera is used for object recognition with an eye-on-hand configuration, which is linked to the end effector to obtain visual information on objects using the YOLOv3 deep learning algorithm. The end effector works optimally on objects with the basic shape of a tube, rectangular prism, hexagon prism and ten-sided prism with a maximum load that can be lifted of 303 grams with a success rate of 71.23%.
While inflation has moderated across most of the euro area since its post-pandemic peak, some countries still face above-average price pressures. In Croatia, inflation has slowed but remains persistent, raising questions about its underlying origins. This paper analyses recent inflationary pressures in Croatia, using firmlevel survey data on production constraints and capacity utilization to untangle supply and demand factors in services and manufacturing, considering sectoral inflation divergence. Unlike traditional approaches, our sectoral output gap captures both supply and demand side drivers of inflationary pressures. Findings show that post-pandemic inflation was mainly driven by supply factors, labour and intermediate input shortages, while ongoing demand pressures, especially in services, continue to fuel inflation. By examining structural and cyclical factors we offer new insights into how inflation behaves in smaller euro area economies, which could help policymakers refine their tools for managing inflation since onesize- fits-all solutions may fall short.
Min-Wen Wang, Wei-Young Wang, Chun-Ming Chen
et al.
Nanoscale amorphous calcium phosphate (ACP) exhibits superior bioactivity, degradability, and osteoblast adhesion compared to hydroxyapatite (HAp), making it a promising bioactive ceramic material for bone regeneration applications. This study explores the integration of ACP as a bioactive additive in polylactic acid/polycaprolactone (PLA/PCL) composites. Nanoscale ACP powder was synthesized through low-temperature wet chemical methods without additional reagents. The composite, consisting of 10 wt.% ACP, 80 wt.% PLA, and 20 wt.% PCL, achieved optimal tensile strength (>12 MPa) and elongation (>0.1%). Utilizing the Taguchi experimental design, the microinjection molding parameters were optimized, and they are a material temperature of 190 °C, an injection speed of 50 mm/s, and a holding pressure speed of 30 mm/s. Variance analysis identified the injection speed to be the most significant factor, contributing 50.73% to the overall effect. Immersing ACP in simulated body fluid (SBF) for six hours reduced its calcium ion concentration by 28%, with this concentration stabilizing thereafter. Biocompatibility was confirmed through an MTT assay with NIH-3T3 cells, demonstrating the PLA/PCL/ACP composite’s compatibility. Bone differentiation and mineralization tests showed the enhanced performance of both ACP and the composite material. Degradation tests indicated an initial 0.29% weight increase in the first week, followed by a 2% reduction by the fifth week. These results underscore the PLA/PCL/ACP composite’s excellent mechanical properties, biocompatibility, and suitability for injection molding, positioning it as a strong candidate for biodegradable bone screw applications.
Diego W. Rivera-Carchi, Yadira E. Villa-Lema, Kelly K. Beltran-Borbor
et al.
The incorporation of brewers’ spent grains (BSG) for food applications has been widely explored due to their high protein, dietary fiber, and bioactive compounds. Additionally, pectin has been shown to improve the texture and expansion of fiber-based extrudates. Cocoa pod husk (CPH), a by-product of cocoa production, is a natural source of pectin, antioxidants, and fibers, yet its use in functional food manufacturing remains unexplored. Therefore, this research aims to explore the potential use of BSG and CPH as functional ingredients in corn-based extrudates. The optimized formulation (10.2 wt.% BSG, 9.8 wt.% CPH) extruded at high temperatures and 30% feed moisture resulted in high polyphenol content (1.855 mg GAE/g), antioxidant capacity (0.2542 µM Trolox eq/g), WSI (15.479%), and WAI (0.8393 g/g). Additionally, the extrudate's low oxalate content (2.25 mg/100 g) ensures its nutritional safety. The combination of these by-products enhanced the functional and physicochemical properties of the extrudate, making it a promising ingredient for the development of health-oriented snacks. These findings highlight the potential of BSG and CPH as functional ingredients, improving the nutritional value of extruded products while contributing to food waste reduction. Future studies should assess sensory attributes and optimal formulations to maximize consumer acceptance.
Chemical engineering, Computer engineering. Computer hardware
The herbal medicine industry is one of the fastest growing industries in the world. However, no detailed assessments have been undertaken on how to achieve the benefits of this industry for developing countries. This study examined the herbal medicine industry in Ghana, with a particular focus on its prospects, challenges and ways forward. The prospects of the medicinal plant trade are huge, and include reducing the national health budget, being a source of foreign and domestic income, as well as creation of employment and poverty reduction. However, the industry is currently inundated with several challenges, such as registration of herbal medicine products and practitioners, a lack of clinical trials for herbal products, standards and quality control issues, shortage of raw plant materials for production, and insufficient scientific research to support traditional claims on the pharmacological effects of medicinal plants. I propose a number of interventions to address these challenges: increased government support, capacity building initiatives, improved regulation of herbal medicines, application of modern technology in the manufacturing of herbal products, large-scale cultivation of medicinal plants, and improved packaging and branding for herbal medicines. Both the national government and the private sector have crucial roles to deliver in the development of the herbal medicine industry in a country like Ghana.
Florian Nahr, Dominic Bartels, Richard Rothfelder
et al.
The commonly used Gaussian intensity distribution during the laser-based processing of metals can negatively affect melt pool stability, which might lead to defects such as porosity, hot cracking, or poor surface quality. Hot cracking is a major factor in limiting production rates of high-strength aluminium alloys in laser-based processes such as welding or the powder bed fusion of metals (PBF-LB/M). Going away from a Gaussian intensity distribution to ring-shaped profiles allows for a more even heat distribution during processing, resulting in more stable melt pools and reduced defect formations. Therefore, the aim of this study is to investigate the influence of different laser beam profiles on the processing of high-strength aluminium alloys by using a multicore fiber laser, allowing for in-house beam shaping. Single weld tracks on the aluminium alloy EN AW-5083 are produced with varying laser powers and weld speeds, as well as different beam profiles, ranging from Gaussian intensity distribution to point/ring profiles. The molten cross sections are analyzed regarding their geometry and defects, and the surface roughness of the weld tracks is measured. By using point/ring beam profiles, the processing window can be significantly increased. Hot cracking is considerably reduced for weld speeds of up to 1000 mm/s compared to the Gaussian beam profile. Furthermore, the melt pool width and depth are more stable, with varying parameters for the point/ring profiles, while the Gaussian beam tends to keyhole formation at higher beam powers. Finally, a strong decrease in surface roughness for the point/ring profiles, accompanied by a significantly reduced humping effect, starting even at lower beam powers of 200 W, can be observed. Therefore, these results show the potential of beam shaping for further applications in laser-based processing of high-strength aluminium alloys.
Robert M. Tona, Reeti Shah, Kimberly Middaugh
et al.
For gene therapies to become more accessible and affordable treatment options, process intensification is one possible strategy to increase the number of doses generated per batch of viral vector. Process intensification for lentiviral vector manufacturing can be achieved by enabling perfusion in the production bioreactor when applied in tandem with a stable producer cell line, allowing for significant expansion of cells and production of lentiviral vectors without the need for transfer plasmids. Tangential flow depth filtration was used to achieve an intensified lentiviral vector production by enabling perfusion to expand cell density and allow for continuous separation of lentiviral vectors from producer cells. Hollow-fiber depth filters made of polypropylene with 2- to 4-μm channels demonstrated high filter capacity, extended functional life, and efficient separation of lentiviral vectors from producer cells and debris when used for this intensified process. We anticipate that process intensification with tangential flow depth filtration at 200-L scale from a suspension culture can produce on the order of magnitude of 10,000 doses per batch of lentiviral vectors required for CAR T or TCR cell and gene therapy that would require approximately 2 × 109 transducing units per dose.
Incremental forming (IF) is an advanced manufacturing process in which a forming tool locally deforms sheet material into a desired geometry through successive passes at incremental depths. An inherent benefit to the IF process is its formability improvement over conventional stamping; however, further enhancements will enable the forming of increasingly complex geometries. To progress the IF process towards heavy industrial use, the modeling of such processes must be further developed. Single point incremental forming (SPIF) of AA2024-T3 was modeled herein utilizing explicit formulations. The model geometry featured a nominally rectangular-shaped clamping region. A friction factor was experimentally determined and utilized within the model, which is a novel addition to this work. Formability was determined and forming limit diagrams were composed. It was found that the present model shows greater formability and underestimates plastic strain compared to experimental testing. The generation of forming limit diagrams for this material processed by IF is also a novel addition to this field.
Rui F. V. Sampaio, João P. M. Pragana, Ivo M. F. Bragança
et al.
This paper introduces a new formability test based on double-action radial extrusion to characterize material formability in the three-dimensional to plane-stress material flow transitions that are found in bulk metal-formed parts. The presentation draws from a multidirectional tool, which was designed to convert the vertical press stroke into horizontal movement of the compression punches towards each other, aspects of experimental strain determination, fractography, and finite element analysis. Results show that three-dimensional to plane-stress material flow transitions at the radially extruded flanges lead to different modes of fracture (by tension and by shear) that may or may not be preceded by necking, such as in sheet metal forming. The new formability test also reveals adequate characteristics to characterize the failure limits of very ductile wrought and additively manufactured metallic materials, which cannot be easily determined by conventional upset compression tests, and to facilitate the identification of the instant of cracking and of the corresponding fracture strains by combination of the force vs. time evolutions with the in-plane strains obtained from digital image correlation.
An additive manufacturing (AM) process, like laser powder bed fusion, allows for the fabrication of objects by spreading and melting powder in layers until a freeform part shape is created. In order to improve the properties of the material involved in the AM process, it is important to predict the material characterization property as a function of the processing conditions. In thermoelectric materials, the power factor is a measure of how efficiently the material can convert heat to electricity. While earlier works have predicted the material characterization properties of different thermoelectric materials using various techniques, implementation of machine learning models to predict the power factor of bismuth telluride (Bi2Te3) during the AM process has not been explored. This is important as Bi2Te3 is a standard material for low temperature applications. Thus, we used data about manufacturing processing parameters involved and in-situ sensor monitoring data collected during AM of Bi2Te3, to train different machine learning models in order to predict its thermoelectric power factor. We implemented supervised machine learning techniques using 80% training and 20% test data and further used the permutation feature importance method to identify important processing parameters and in-situ sensor features which were best at predicting power factor of the material. Ensemble-based methods like random forest, AdaBoost classifier, and bagging classifier performed the best in predicting power factor with the highest accuracy of 90% achieved by the bagging classifier model. Additionally, we found the top 15 processing parameters and in-situ sensor features to characterize the material manufacturing property like power factor. These features could further be optimized to maximize power factor of the thermoelectric material and improve the quality of the products built using this material.
This study analyzed the characteristics of viscosity change and oil leakage stability according to the average particle size and content of organic and mineral-based extenders such as CaCO<sub>3</sub> (CA) and anti-sedimentation (ASE) among materials consisting of bituminous emulsion mastic (BEM). The fabrication of samples for research was done using a melting method of 2 L capacity with the production mixing ratio of BEM used in the actual manufacturing process as a standard mixing ratio. Each sample size was adjusted to 16 μm, 5 μm, 2 μm, 1.4 μm and 1 μm, the average particle size of CA as a variable, and the content of ASE for each particle size was set to increase from 1 to 6 times the standard mixing ratio. The analysis found that in all average particle sizes of CA, the viscosity increased as the content of anti-sedimentation increased, and the viscosity was highest at the CA average particle size of 16 μm. The viscosity increased as the average particle size decreased at 5 μm, 2 μm, 1.4 μm and 1 μm. In addition, it was confirmed that the oil leakage stability increased as the average particle size of CA decreased, and the content of ASE increased. The evaluation results showed that specimens that met both workability and oil leakage stability conditions were the specimens with 4 times and 5 times the ASE content at the CA average particle size of 2 μm, and those with twice the ASE content at the CA average particle size of 1.4 μm.
Daniyar Syrlybayev, Aidana Seisekulova, Didier Talamona
et al.
The traditional manufacturing industry has been revolutionized with the introduction of additive manufacturing which is based on layer-by-layer manufacturing. Due to these tool-free techniques, complex shape manufacturing becomes much more convenient in comparison to traditional machining. However, additive manufacturing comes with its inherent process characteristics of high surface roughness, which in turn effect fatigue strength as well as residual stresses. Therefore, in this paper, common post-processing techniques for additive manufactured (AM) parts were examined. The main objective was to analyze the finishing processes in terms of their ability to finish complicated surfaces and their performance were expressed as average surface roughness (Sa and Ra). The techniques were divided according to the materials they applied to and the material removal mechanism. It was found that chemical finishing significantly reduces surface roughness and can be used to finish parts with complicated geometry. Laser finishing, on the other hand, cannot be used to finish intricate internal surfaces. Among the mechanical abrasion methods, abrasive flow finishing shows optimum results in terms of its ability to finish complicated freeform cavities with improved accuracy for both polymer and metal parts. However, it was found that, in general, most mechanical abrasion processes lack the ability to finish complex parts. Moreover, although most of post-processing methods are conducted using single finishing processes, AM parts can be finished with hybrid successive processes to reap the benefits of different post-processing techniques and overcome the limitation of individual process.
Abstract Advancements in material science have led to the development of new composites and biomaterials. Spider silk and human collagen are examples of animal-derived polymers for which sourcing has been challenging. Interest in strong, sustainable products derived from these biopolymers and increasing demand in bio-based solutions are driving forces for investments in non-animal-based production processes namely for use in biomedical applications. An outline of the current landscape of microbial-based bioprocesses is a useful tool to guide further development of novel biomaterials based on these proteins. While bioproduction can deliver a sustainable source for human collagen and for spider silk, it has been challenging to obtain the desired products via microbial-based bio-industrial processes. Optimization through improvements in upstream processes and better adapted large-scale downstream process steps, including replacing chromatography steps with freeze drying and autoclaving for endotoxin removal (silk) and filtration (collagen) has enabled large-scale production and recent capacity expansion of manufacturing, aiming to deliver hundreds of tonnes of product per year. This article reviews the considerable advances that were made in microbial processes for production of human collagen and spider-silk based biomaterials in the past 30 years in translating the laboratory results into scalable processes. Main challenges for successful large-scale implementation—such as recombinant silk durability and the continuous need to improve process economics—and main opportunities such as demand growth of recombinant spider silk and human collagen are outlined.
Materials of engineering and construction. Mechanics of materials
We construct a bijection between the state of the box-ball system with box capacity L and a pair of two sequences. In time evolution, one of the sequences moves at speed 1, and the other follows the rules of the box-ball system with box capacity one, which can be linearized by the Kerov-Kirillov-Reshetikhin(KKR) bijection. Our method can be applied to a state including a negative value or a value greater than the box capacity.
Multi-element systems with defined entropy (HEA—high entropy alloy or MEA—medium entropy alloy) are rather new material concepts that are becoming increasingly important in materials research and development. Some HEA systems show significantly improved properties or combinations of properties, e.g., the overcoming of the trade-off between high strength and ductility. Thus, the synthesis, the resulting microstructures, and properties of HEA have been primarily investigated so far. In addition, processing is crucial to achieve a transfer of potential HEA/MEA materials to real applications, e.g., highly stressed components. Since fusion welding is the most important joining process for metals, it is of vital importance to investigate the weldability of these materials. However, this has rarely been the subject of research to date. For that reason, in this work, the weldability depending on the surface preparation of a CoCrFeMnNi HEA and a CoCrNi MEA for TIG welding is investigated. The fusion welding of longer plates is described here for the first time for the CoCrNi alloy. The welds of both materials showed distinct formation of cracks in the heat affected zone (HAZ). Optical and scanning electron microscopy analysis clearly confirmed an intergranular fracture topography. However, based on the results, the crack mechanism cannot be conclusively identified as either a liquid metal embrittlement (LME) or hot cracking-like liquid film separation.
We investigate the existence of a maximiser among open, bounded, convex sets in $\R^d,\,d\ge 3$ for the product of torsional rigidity and Newtonian capacity (or logarithmic capacity if $d=2$), with constraints involving Lebesgue measure or a combination of Lebesgue measure and perimeter.
Conditional disclosure of secrets (CDS) is the problem of disclosing as efficiently as possible, one secret from Alice and Bob to Carol if and only if the inputs at Alice and Bob satisfy some function $f$. The information theoretic capacity of CDS is the maximum number of bits of the secret that can be securely disclosed per bit of total communication. All CDS instances, where the capacity is the highest and is equal to $1/2$, are recently characterized through a noise and signal alignment approach and are described using a graph representation of the function $f$. In this work, we go beyond the best case scenarios and further develop the alignment approach to characterize the linear capacity of a class of CDS instances to be $(ρ-1)/(2ρ)$, where $ρ$ is a covering parameter of the graph representation of $f$.
Matt Beekman, Jonathan Fernsler, Thomas D. Gutierrez
Seemingly different interpretations or descriptions of Einstein's model for the heat capacity of a solid can be found in textbooks and the literature. The purpose of this note is to clarify the equivalence of the different descriptions, which all lead to the same Einstein expression for the heat capacity of a solid of N atoms.