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The industry of off-highway vehicles is one of the fields of major application of nodular cast irons, which guarantee the manufacture of complex geometries and ensure good mechanical properties. The present investigation deals with the fatigue design of off-highway axles made of EN-GJS-500-7. Typically, off-highway axles are weakened by stress risers which must be assessed against fatigue. In this investigation, laboratory specimens have been extracted from an off-highway axle to take into account the manufacturing process effects. Different specimens' geometries have been prepared, including plain, bluntly notched and sharply V-notched specimens, and constant amplitude, load-controlled axial fatigue tests were conducted using two nominal load ratios, namely push-pull and pulsating tension loading. As a result, both the notch and the mean stress effects on the fatigue behaviour of EN-GJS-500-7 have been experimentally investigated for the first time. A well-known local approach, which takes the strain energy density (SED) averaged over a properly defined structural volume as a fatigue damage parameter, has been applied both in the linear elastic and elastic plastic formulations. Since the SED correlated the geometrical notch effects of the specimens as well as the mean stress effects, a master curve based on the averaged SED has been defined for the first time, to the best of the authors' knowledge, for the fatigue design of off-highway axles made of EN-GJS-500-7.
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Conducting polymers used in chemical sensors are attractive because of their ability to confer reversible properties controlled by the doping/de-doping process. Polyaniline (PANI) is one of the most prominent materials used due to its ease of synthesis, tailored properties, and higher stability. Here, PANI thin films deposited by the drop-casting method on fluorine-doped tin oxide (FTO) substrates were used in electrochemical and optical sensors for pH measurement. The response of the devices was correlated with the deposition parameters; namely, the volume of deposition solution dropped on the substrate and the concentration of the solution, which was determined by the weight ratio of polymer to solvent. The characterisation of the samples aimed to determine the structure-property relationship of the films and showed that the chemical properties, oxidation states, and protonation level are similar for all samples, as concluded from the cyclic voltammetry and UV-VIS spectroscopic analysis. The sensing performance of the PANI film is correlated with its relative physical properties, thickness, and surface roughness. The highest electrochemical sensitivity obtained was 127.3 ± 6.2 mV/pH, twice the Nernst limit-the highest pH sensitivity reported to our knowledge-from the thicker and rougher sample. The highest optical sensitivity, 0.45 ± 0.05 1/pH, was obtained from a less rough sample, which is desirable as it reduces light scattering and sample oxidation. The results presented demonstrate the importance of understanding the structure-property relationship of materials for optimised sensors and their potential applications where high-sensitivity pH measurement is required.
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BACKGROUND: Various treatment approaches for individuals with ankle sprains can reduce treatment costs and enhance recovery. This study aimed to compare the efficacy of spring ankle braces with splints and casts in treating ankle sprains. MATERIALS AND METHODS: This cross-sectional study involved 60 patients diagnosed with ankle sprains at the orthopedic clinic of Imam Khomeini Hospital in Jiroft in 2022. Following diagnosis confirmation through additional examinations and imaging, patients with ankle sprains not requiring surgery were selected and placed in two groups: one treated with spring ankle braces and the other with splints or casts. Both groups underwent a 4-week treatment regimen, comprising 30 individuals each. Data were collected and analyzed using SPSS version 26. RESULTS: The average age of patients was 32.5 ± 13.4 years. Of the ankle sprain patients, 56.7% were male. Patients reported the highest satisfaction levels with the plaster cast treatment method. A statistically significant relationship was found between patient satisfaction and the treatment methods of spring ankle braces and plaster casting (P < 0.05). Patients treated with plaster casts reported the lowest pain levels, with a significant relationship between pain levels and the two treatment methods (P < 0.05). Range of motion results were similar for both treatment methods, while the cast treatment showed the highest incidence of skin complications. A significant relationship was observed between spring ankle braces and plaster casts regarding skin complications (P < 0.05). CONCLUSION: Treating ankle sprains with plaster casts leads to higher satisfaction and lower pain levels compared to using spring ankle braces.
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Traumatismos do Tornozelo , Braquetes , Moldes Cirúrgicos , Contenções , Humanos , Masculino , Feminino , Traumatismos do Tornozelo/terapia , Adulto , Estudos Transversais , Pessoa de Meia-Idade , Adulto Jovem , Resultado do Tratamento , Amplitude de Movimento Articular , Satisfação do Paciente , Entorses e Distensões/terapia , Entorses e Distensões/diagnóstico , Adolescente , Articulação do Tornozelo/patologiaRESUMO
In recent years, the application of 3D printing technology in the energetic materials field has proved its ability to innovate traditional charging methods and fabricate complex structures to improve combustion/detonation performance. The melt extrusion technology is the most promising way to fabricate complex structures and multiple components of melt-cast explosives. In this study, a paraffine-based composite was used to substitute melt-cast explosives, and a Design of Experiments approach based on central composite design was adopted to investigate the influence of layer thickness, percent infill, extrusion temperature, and printing velocity on the roughness of printed samples. The results showed that layer thickness and printing velocity could significantly influence the roughness of printed specimens, and no obvious voids or cracks inside the specimens can be detected in computed tomography. In addition, a composite-shaped grain was successfully fabricated via the EAM-D-1 printer, which proved the feasibility of 3D printing melt-cast explosives with complex structures. This work will greatly help to achieve 3D printing melt-cast explosives with complex structures and higher accuracy.
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Eucalyptus oil consumption is well known to cause adverse effects on central nervous system like seizures, ataxia and unconsciousness. No antidote is available and treatment is largely supportive. We report a case of rhabdomyolysis with pigment cast nephropathy and acute kidney injury in a young female following eucalyptus oil consumption and its successful management.
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Myoglobin cast nephropathy is a sequel of rhabdomyolysis, and is characterized by the release of free myoglobin in the circulation, direct proximal convoluted tubule injury, and obstruction by myoglobin cast in distal tubules. We report an interesting case of myoglobin cast nephropathy in a patient who was on neuroleptic drugs and who presented with neuroleptic malignant syndrome and acute kidney injury.
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Introduction: In the treatment of paediatric supracondylar humerus fractures (SCHFs), Gartland Type 1 fractures are traditionally managed with in situ above elbow casting, while Type 2A fractures are treated with closed reduction and above elbow casting. Surgical Technique: This technical note introduces a novel "figure of 8" cast technique for Type I and 2A fractures. The technique aims to maintain fracture reduction while reducing the risk of compartment syndrome by avoiding placement of cast material in the anterior elbow crease. This innovative casting method has the potential to enhance the management of these fractures in children, providing a alternative to conventional approaches. Conclusion: "Figure of 8" cast technique presents a unique, easy-to-implement, and effective approach for treating Type 1 and 2A SCHFs in children, maintaining fracture reduction in 100-110° elbow flexion and minimizing the risk of compartment syndrome.
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The synthesis and characterization of low-melting-point insensitive energetic materials are crucial due to their increasing applications in melt-cast explosives. In this work, a furazan-derived energetic compound, 3,4-bis[3(2-azidoethoxy)furazan-4-yl]furoxan (DAeTF), exhibiting insensitive and high-energy characteristics, is rationally designed and synthesized. The structure of DAeTF is characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, elemental analysis, mass spectrometry, and single-crystal X-ray diffraction. The thermal properties of DAeTF are investigated using differential scanning calorimetry, in situ FTIR spectroscopy and thermogravimetric-differential scanning calorimetry-Fourier transform infrared-mass spectrometry and thermal decomposition mechanism was elucidated in combination with bond energy calculations. The detonation performance of DAeTF is predicted by the EXPLO5 program. The results indicate that DAeTF has thermal stability (Td = 251.7 °C), high energy level (D = 7270 m/s) and significant insensitivity (IS = 60 J). Additionally, its relatively low melting point (Tm = 60.5 °C) facilitates processing and loading. These characteristics indicate that DAeTF is a promising candidate as an insensitive melt-cast explosive in future applications.
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AIM: The aim of this study was to compare the fitting accuracy of custom-made metal posts and cores fabricated by half-digital and milling technique to that of conventional cast posts fabricated by direct technique. METHODS: Sixteen extracted single-rooted teeth were endodontically treated followed by post space preparation. A direct resin post and core pattern was made for each tooth and used for the fabrication of two posts (n = 16). Each post resin pattern was digitized with a laboratory scanner and used for the fabrication of a milled cobalt-chrome (Co-Cr) alloy post, while the direct resin pattern, after scanning, was cast in a Co-Cr alloy to produce a cast post. Each post was seated on its respective tooth and evaluated using microcomputed tomography. The following variables were evaluated: total space volume between the post and root canal, the volume and distance of the apical gap between each post and the remaining apical root canal filling, as well as the distance and surface area of the space between the post and lateral root canal wall at four determined points along the length of each post. RESULTS: The results revealed that half-digital and milled posts had a statistically significantly higher total space volume (p < 0.05), apical gap volume (p < 0.02) and distance (p < 0.02), as well as a higher surface area of space between the post and root canal wall at the cervical area as compared to the cast post (p < 0.05). CONCLUSIONS: This study demonstrated that the fitting accuracy of cast posts was more accurate than posts fabricated with half-digital and milling technique.
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The study examined the effect of heat treatment parameters of compacted graphite iron (CGI) on the mechanical properties of the material. The microstructure was characterized using optical microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Three levels of heat treatment parameters were adopted considering the orthogonal test plan 24. The effects of austenitizing temperature and time and austempering on tensile strength, yield strength, and elongation were analyzed. Polynomial regression was chosen because it extends linear regression and allows for modeling more complex, nonlinear relationships between variables. Total regression models were determined for each dataset. The models for tensile strength (Rm) had an approximately 82% coefficient of determination, for yield strength (R0.2) around 50%, and for elongation (A5) around 80%. For optimization, the response surface method (RSM) was used. The results obtained were compared with the proposed mathematical models. The ANOVO results showed that austempering temperature (Tpi) had the greatest effect on each parameter studied. The optimal conditions for the analyzed parameters, assuming tensile strength and yield strength at the maximum level and an elongation of about 0.7%, are obtained for the following heat treatment parameters: Tγ = 890 °C; Tpi = 290 °C; τγ = 120 min; τpi = 150 min.
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In developing materials for the nuclear industry, it is crucial to enhance both alloy composition and processing methods. This study focuses on investigations of applying radial-shear rolling (RSR) to a Zr-1%Nb alloy ingot, aiming to refine its microstructure and improve its properties for nuclear applications. This method, with complex vortex metal flow inside of a casted workpiece, has not been previously tested for processing zirconium ingots, so experimental verification of its applicability is of scientific interest. The 30 mm diameter ingot, produced by vacuum induction melting, was initially rolled to 20 mm at 800 °C to eliminate defects and refine the cast structure. A second rolling stage reduced the diameter to 13 mm at 530 °C, resulting in an ultrafine-grained structure. The RSR method effectively combines structural refinement and defect healing within fewer cycles, making it suitable for producing components for nuclear reactors. This approach demonstrates a potential reduction in traditional processing steps, providing a more efficient route for preparing high-quality materials for nuclear applications.
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Cerebral palsy (CP) is a group of movement disorders that impair posture and mobility, often leading to spasticity and joint contractures. Interventions like serial casting are commonly used to improve joint mobility and manage spasticity in children with CP. However, its effects on the autonomic nervous system (ANS) remain unclear. This study aimed to evaluate the effects of serial casting and ankle-foot orthoses (AFOs) on ANS responses during a virtual reality (VR) standing task, comparing these interventions with a barefoot condition. Thirty children with CP were randomized into three groups (n = 10 per group): serial casting, AFOs, and barefoot. Heart rate variability (HRV) was used to assess ANS responses across three phases: seated rest, VR task, and recovery. The results showed that the serial casting group exhibited higher sympathetic activity during rest compared to the other groups, but had a reduced sympathetic response during the VR task. Additionally, the serial casting group displayed a more pronounced parasympathetic rebound during recovery, similar to the orthoses and barefoot groups. While serial casting provides essential joint stability, it alters ANS response patterns, leading to heightened sympathetic activation at rest, without providing significant improvements in ANS behavior during physical activity.
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The Coastal Creole pigs in Argentina are predominantly found in the wild and can trace their lineage directly back to the Iberian breeds introduced by Spanish colonizers. They currently stand as the sole Creole breed in the country recognized by the FAO. However, there exists a dearth of studies assessing their genetic potential within the swine industry. Therefore, this study aimed to genetically characterize the meat quality of Coastal Creole pigs based on seven single nucleotide polymorphisms (SNPs) within the Ryr1, PRKAG3, MC4R, H-FABP, and CAST genes. A total of N = 158 samples were collected from specimens distributed along the coastal region. Our findings revealed all loci to exhibit polymorphism, underscoring the population's remarkable genetic diversity. Furthermore, a higher frequency of alleles favorable for the PRKAG3191I>V/200R>Q, MC4R1426A>G, CAST76872G>A, and Ryr11843C>T genes was observed, while alleles unfavorable predominated for H-FABP1811G>C and CAST638Ser>Arg. The results obtained in this research are highly encouraging, reflecting the genetic potential of these pigs to be utilized in swine production programs.
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Polimorfismo de Nucleotídeo Único , Sus scrofa , Animais , Argentina , Sus scrofa/genética , Carne/análise , Canal de Liberação de Cálcio do Receptor de Rianodina/genéticaRESUMO
Natural debris deposited by the sea is essential for the functioning of the beach ecosystem. As tourist demands on the coast grow, aesthetic values become more important, and the indiscriminate cleaning of debris spreads from urban to natural beaches. A change in beach debris management is needed to ensure that organic debris plays its role where the sea has deposited it.
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There are lots of gene editing tools for targeting genome sequences. Some are almost known, and most are a complete mystery and undiscovered. CRISPR/Cas editing tools have brought about a major revolution in medicine. Researchers have shown that CRISPR can modify DNA much more accurately, economically and easily than previous methods. CRISPR has proven itself effective for the deletion, replacement and insertion of DNA fragments into cell types, tissues and organisms. Recently, combining CRISPR/Cas with factors (transcription factors/repressors, exonucleases, endonucleases, transposons, caspase, fluorescent proteins, oxidoreductive enzymes, DNA/RNA polymerases), and elements (aptamers, barcodes, fluorescent probes, Trigger) have provided genome, transcriptome, proteome and epigenome modification. These modules are being investigated for cancer prevention and therapy and this review focuses on such innovative combinations that hopefully will become a clinical reality in the near future.
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Sistemas CRISPR-Cas , Edição de Genes , Neoplasias , Neoplasias/genética , Neoplasias/terapia , Neoplasias/prevenção & controle , Humanos , Edição de Genes/métodos , Animais , Terapia Genética/métodosRESUMO
In salt lake areas, the cast-in-situ concrete structure has been corroded by the combination of sulfate and chloride for a long time. The incorporation of basalt fiber materials into concrete helps to improve the durability of concrete. In this paper, experiments were conducted to study the corrosion deterioration mechanisms of basalt fiber-reinforced cast-in-situ concrete under sulfate, chloride, and combined attack. The appearance, size, mass, flexural, and compressive strength of specimens were investigated during the immersion period to determine the changes in the physical and mechanical properties of specimens. Moreover, the microstructure and mineral changes of specimens during the immersion period were observed by Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS), X-ray diffraction (XRD), and Thermogravimetric (TG)/ Derivative Thermogravimetric (DTG) analyses. Results show that premixed chloride has a significant detrimental influence on the strength development of cast-in-situ concrete, with concrete powder spalling occurring on the surface of the specimen. Severe corrosion degradation of specimens occurs under the external sulfate and internal chloride combined attack, resulting in lower flexural and compressive strength. The compressive strength and flexural strength of the corroded specimens decreased by 15.4% and 24.8%, respectively, compared with the control group at 28 days. Moreover, premixed basalt fiber has a beneficial influence on cast-in-situ concrete. When the basalt fiber content is 0.5%, the flexural strength of the specimen is increased by 16.2%. The filling and bridging effect of basalt fiber alleviates the negative effects caused by corrosion. In addition, increasing fiber content is beneficial for enhancing its effectiveness when the fiber content is less than 0.5%. This paper provides a valuable reference for the application of basalt fiber-reinforced cast-in-situ concrete under the condition of sulfate-chloride compound corrosion.
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INTRODUCTION: Computed tomography can be used to screen and diagnose the presence of drug-filled packets in the body. We present an unusual computed tomography finding in a suspected body packer. CASE SUMMARY: A traveller suspected of being a body packer was brought to the emergency department complaining of low back pain. On examination, there was an abdominal cast circumferentially encasing his abdomen, which he alleged was part of the management of his lower back pain in his own country. IMAGES: A plain computed tomogram of the abdomen and pelvis revealed that the cast was made of materials with a nodular appearance and heterogeneous density, which was different from that of a plaster of Paris cast. An investigation later confirmed the cast contained cocaine. CONCLUSION: Our case demonstrates how a body packer can traffic drugs outside their body for an alleged medical reason.
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A meta-analysis including all relevant randomized controlled trials was conducted to compare soft bandage, splint and cast as the treatment of torus fracture. PubMed, Scopus, and Web of Science databases were searched in January 2023. Two comparisons were made: (1) splint versus cast, and (2) bandage versus rigid immobilization (i.e. splint or cast). Main outcomes were pain, clinical healing of the fracture and return to activities. Secondary outcomes were adverse events (skin issues, problems with cast/splint/bandage) and patient/parental satisfaction. Seven studies with 1550 patients were included. Splint was associated with higher pain scores at 3 days compared to cast (Mean difference [MD] 1.00, CI 0.06-1.94) and at 1 week (MD 1.46, CI 0.84-2.08, moderate-certainty evidence), but faster return to activities (at 3 weeks RR 1.77, CI 1.09-2.88, at 4 weeks RR 1.44, CI 1.11-1.82, moderate-certainty evidence). All torus fractures heal clinically within 3-4 weeks (low-certainty evidence). Bandage may lead to slightly higher pain score (MD 0.35, CI 0.04-0.66, moderate-certainty evidence) at first day after treatment compared to rigid immobilization, but no evidence of a difference was found in later time points. In conclusion, soft bandage or removable wrist splint seem to be optimal first-line treatment of distal forearm torus fracture.
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Bandagens , Moldes Cirúrgicos , Contenções , Humanos , Criança , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Traumatismos do Antebraço/terapiaRESUMO
Laser beam remelting is a relatively simple and highly effective technique for the physical modification of surfaces to improve resistance to cavitation erosion. In this study, we investigated the effect of laser remelting on the surface of cast stainless steel with 0.40% C, 25% Cr, 20% Ni, and 1.5% Si on cavitation erosion behavior in tap water. The investigation was conducted using a piezoceramic crystal vibrator apparatus. Base laser beam parameters were carefully selected to result in a defect-free surface (no porosity, material burn, cracks) with hardness capable of generating better resistance to cavitation erosion. The experimental results were compared with those of the reference material. Surface morphology and microstructure evolution after cavitation tests were analyzed using an optical metallographic microscope (OM), scanning electron microscope (SEM), and hardness tests to explore the mechanism of improving surface degradation resistance. The conducted research demonstrated that surfaces modified by laser remelting exhibit a 4.8-5.1 times greater increase in cavitation erosion resistance due to the homogenization of chemical composition and refinement of the microstructure, while maintaining the properties of the base material.
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Tensile and low-cycle fatigue tests of high-strength compacted graphite cast iron (CGI, RuT450) were carried out at 25 °C, 400 °C, and 500 °C, respectively. The results show that with the increase in temperature, the tensile strength decreases slowly and then decreases rapidly. The fatigue life decreases, and the life reduction increases at high temperature and high strain amplitude. The oxide layer appears around the graphite and cracks at high temperature, and the dependence of crack propagation on ferrite gradually decreases. With the increase in strain amplitude, the initial cyclic stress of compacted graphite cast iron increases at three temperatures, and the cyclic hardening phenomenon is obvious. The fatigue life prediction method based on the energy method and damage mechanism for compacted graphite cast iron is summarized and proposed after comparing and analyzing a large amount of fatigue data.