Parametric Optimization of FDM Process for PA12-CF Parts Using Integrated Response Surface Methodology, Grey Relational Analysis, and Grey Wolf Optimization.

Efficiently managing multiple process parameters is critical for achieving optimal performance in additive manufacturing. This study investigates the relationship between eight key parameters in fused deposition modeling (FDM) and their impact on responses like average surface roughness (Ra), tensile strength (TS), and flexural strength (FS) of carbon fiber-reinforced polyamide 12 (PA 12-CF) material. The study integrates response surface methodology (RSM), grey relational analysis (GRA), and grey wolf optimization (GWO) to achieve this goal. A total of 51 experiments were planned using a definitive screening design (DSD) based on response RSM. The printing process parameters, including layer thickness, infill density, and build orientation, significantly affect Ra, TS, and FS. GRA combines responses into a single measure, grey relational grade (GRG), and a regression model is developed. GWO is then employed to optimize GRG across parameters. Comparison with GRA-optimized parameters demonstrates GWO's ability to discover refined solutions, reducing average surface roughness to 4.63 µm and increasing tensile strength and flexural strength to 88.5 MPa and 103.12 MPa, respectively. Practical implications highlight the significance of GWO in industrial settings, where optimized parameters lead to reduced costs and improved product quality. This integrated approach offers a systematic methodology for optimizing FDM processes, ensuring robustness and efficiency in additive manufacturing applications.

Hypokalemic periodic paralysis in a teenage boy after an intense period of exercise: A rare case report.

Key Clinical Messages: Diagnosis of rare even can be missed due to less familiarity with the disorder.In patients with muscle weakness, infectious causes are prioritized.Electrolyte profile not only identifies the problem, but also prevents unnecessary workup. Abstract: In underdeveloped countries, diagnosis of rare disorders is usually delayed due to less familiarity of the clinicians to such disorders. As a result, infectious and inflammatory causes for an ailment are prioritized as compared to non-infectious etiologies. Hypokalemic periodic paralysis (PP) is a rare disorder, characterized by episodic muscle weakness that can rarely be associated with life-threatening cardiac arrhythmia. A teenage Afghan boy presented to the emergency department with an acute flaccid paralysis, that started 1 h after intense exercise The weakness involved both, the upper and lower extremities. Laboratory investigations, led to the impression of hypokalemic PP, precipitated by intense exercise. Accordingly, intravenous potassium chloride infusion diluted with normal saline led to the complete resolution of paralysis as well as correction of electrocardiographic changes. The list of differential diagnosis for flaccid muscle paralysis is wide, which generally requires a extensive investigations, but in hypokalemic PP, a cardinal electrolytes profile can lead towards early diagnosis. High degree of clinical suspicion with appropriate history taking and physical examination helps with the immediate identification and management of this disorder.

Forty days old infant with Pig Bronchus, presenting with recurrent pneumonia: A Case Report.

Background: Pig bronchus is rare and usually asymptomatic, but it may also cause significant respiratory symptoms such as recurrent pneumonia, chronic bronchitis, atelectasis, and difficult airway management in surgical and critical care patients. This study is aimed to examine a case of pig bronchus in which the patient presented with recurrent pneumonia in her early days of life. Case Report: A case report is the study design utilized in this assessment of a 40-days-old girl from a consanguineous marriage, who presented with cough and difficulty breathing for approximately a month. She was referred from a provincial hospital with no improvement in respiratory symptoms after three times hospitalization since birth. Radiological investigation revealed pig bronchus as the cause of recurrent pneumonia. Conclusion: Pig bronchi, if not diagnosed on time, may result in severe lung infection that can even result in fatal disease. A high level of clinical suspicion is required to initiate an appropriate diagnostic workup. The gold standard modality for the diagnosis of pig bronchus is computed tomography (CT), ideally with multi-detector three-dimensional (3D) image reconstruction.

Analyzing Surface Roughness Variations in Material Extrusion Additive Manufacturing of Nylon Carbon Fiber Composites.

In recent years, fused deposition modeling (FDM) based on material extrusion additive manufacturing technology has become widely accepted as a cost-effective method for fabricating engineering components with net-shapes. However, the limited exploration of the influence of FDM process parameters on surface roughness parameters, i.e., Ra (average surface roughness), Rq (root mean square surface roughness), and Rz (maximum height of the profile) across different sides (bottom, top, and walls) poses a challenge for the fabrication of functional parts. This research aims to bridge the knowledge gap by analyzing surface roughness under various process parameters and optimizing it for nylon carbon fiber printed parts. A definitive screening design (DSD) was employed for experimental runs. The Pareto chart highlighted the significant effects of layer height, part orientation, and infill density on all surface roughness parameters and respective sides. The surface morphology was analyzed through optical microscopy. Multi-response optimization was performed using an integrated approach of composited desirability function and entropy. The findings of the present study hold significant industrial applications, enhancing the quality and performance of 3D printed parts. From intricate prototypes to durable automotive components, the optimized surfaces contribute to production of functional and visually appealing products across various sectors.

Demographic and clinical characteristics of acute myeloid leukaemia diagnosed and treated at the tertiary level in Afghanistan.

A retrospective case series design was conducted to elucidate the demographic features of acute myeloid leukaemia in Afghanistan. This study was conducted at Jamhuriat Hospital and French Medical Institute for Mothers and Children, Kabul, Afghanistan. A total of 203 patients with AML diagnosed and managed at Jamhuriat Hospital from 1 March 2018 to 31 March 2020, were included in the current study. The median age at diagnosis was 27 years. Housewives represented the largest subset of patients from an occupational point of view constituting 37.44% of the total sample population and 81.72% of the female population, followed by 20.69% patients who were students of which 14.77% were male and 5.91% were female, and 17.24% were farmers, which constituted 31.81% of the male population. Similarly, 69.95% of individuals presented with infection, 57.14% presented with bone tenderness, 46.3% presented with bleeding tendencies, 55.66% had hepatomegaly and/or splenomegaly, and 27.58% of patients had lymphadenopathy. Considering the chemotherapeutic regime, 64.53% of the individuals received standard 7 + 3 (cytarabine + daunorubicin) induction regimen, 10.68% of those received 5 + 2 re-induction chemotherapy (cytarabine + daunorubicin). 10.84% who were diagnosed with acute promyelocytic leukaemia received all-trans-retinoic acid + arsenic trioxide, while 5.42% of patients defaulted chemotherapy. High prevalence was noted in young individuals. Similarly, a high proportion of patients were constituted by housewives.

Albright hereditary osteodystrophy: Delay in the diagnosis of a rare disorder due to restricted medical services.

A teenage Afghan girl presented with seizure. Clinical features and laboratory investigations revealed elevated serum parathormone, high phosphate levels with low serum calcium. In third-world countries, diagnosis of rare disorders, such as Albright hereditary osteodystrophy (AHO), can usually be delayed due to scarcity of standard medical and diagnostic services.

Acute lymphoblastic leukemia with clonal evolution due to delay in chemotherapy: A report of a case.

Clonal evolution in acute leukemias is one of the most important factors that leads to therapeutic failure and disease relapse. Delay in therapeutic intervention is one of the reasons that leads toward clonal evolution. In this report, we present a case of acute lymphoblastic leukemia in which therapeutic delay resulted in clonal evolution that was detected by conventional karyotyping and was responsible for non-responsiveness of the disease to conventional chemotherapy. A 17-year-old boy presented with generalized body aches, rapidly progressive pallor and lethargy. Bone marrow analysis was consistent with the diagnosis of B-cell ALL. Karyotypic analysis revealed 46, XY male karyotype. The patient left the hospital due to financial reasons and after 40 days came back to the hospital. Repeated bone marrow analysis including cytogenetic studies revealed presence of three different clones of blast cells: one clone showed 46, XY with del(9p) and t (11;14), second clone showed 46, XY with del(7q) and del(9p), and the third clone showed 46, XY normal karyotype. The patient did not respond to chemotherapy and died within 1 week of induction chemotherapy (HyperCVAD-A). Timely diagnosis and institution of chemotherapy in acute leukemias patients is the key to prevent clonal evolution and thus resistance of the disease to therapeutic interventions.

Parametric Investigation and Optimization to Study the Effect of Process Parameters on the Dimensional Deviation of Fused Deposition Modeling of 3D Printed Parts.

Fused deposition modeling (FDM) is the most economical additive manufacturing (AM) technology available for fabricating complex part geometries. However, the involvement of numerous control process parameters and dimensional instabilities are challenges of FDM. Therefore, this study investigated the effect of 3D printing parameters on dimensional deviations, including the length, width, height, and angle of polylactic acid (PLA) printed parts. The selected printing parameters include layer height, number of perimeters, infill density, infill angle, print speed, nozzle temperature, bed temperature, and print orientation. Three-level definitive screening design (DSD) was used to plan experimental runs. The results revealed that infill density is the most consequential parameter for length and width deviation, while layer height is significant for angle and height deviation. The regression models developed for the four responses are non-linear quadratic. The optimal results are obtained considering the integrated approach of desirability and weighted aggregated sum product assessment (WASPAS). The optimal results include a layer height of 0.1 mm, a total of six perimeters, an infill density of 20%, a fill angle of 90°, a print speed of 70 mm/s, a nozzle temperature of 220 °C, a bed temperature of 70 °C, and a print orientation of 90°. The current study provides a guideline to fabricate assistive devices, such as hand and foot orthoses, that require high dimensional accuracies.

Rare additional chromosomal abnormalities in acute promyelocytic leukaemia resulting in rapidly fatal disease: report of a case.

Background: Acute promyelocytic leukaemia results from reciprocal translocation between the long arms of chromosomes 15 and 17. This translocation leads to the formation of chimeric gene, which is both the diagnostic marker as well as the therapeutic target of the disease. Additional chromosomal abnormalities are randomly encountered either at diagnosis or during therapy. Here, we present a case of acute promyelocytic leukaemia that had a rare cytogenetic profile at diagnosis. Case presentation: Our patient was a 14-year-old boy, who presented with characteristic clinical and morphological features of acute promyelocytic leukaemia. Karyotypic analysis revealed trisomy of chromosome 8 with deletion of 9p in addition to t(15;17). The patient passed away within the first 8 h of presentation while receiving conventional chemotherapy and haemodynamic resuscitation. Conclusion: Our patient presented with a rare cytogenetic profile and rapidly progressive disease. According to our extensive literature search, this was the first case of acute promyelocytic leukaemia having pathognomonic t(15;17) along with trisomy 8 and 9q deletion.

Experimental and Statistical Analysis of Saw Mill Wood Waste Composite Properties for Practical Applications.

The utilization of composite materials is increasing at a growing rate in almost all types of products, due to their strength-to-stiffness ratio. From this perspective, natural waste composites, i.e., wood waste composites, have also been investigated for their effective and sustainable employment. This paper deals with the application of hard and soft wood waste (i.e., acacia and cedar wood) with epoxy resin polymer to develop high strength and thermally stable wood composites. Mechanical (tensile, flexural, impact, and hardness) and thermal properties of samples are studied using Differential Scanning Calorimeter (DSC) and Thermo Gravimetric Analysis (TGA), respectively. The properties are evaluated by varying the type of wood waste and its percentage by weight. Based on the Taguchi Orthogonal Array Mixture Design, eighteen experiments are investigated. Analysis of variance (ANOVA) results show that wood waste type and wood waste content have a significant effect on all mechanical properties. From the TGA analysis, it is predicted that both types of wood waste composites exhibit similar thermal-induced degradation profiles in terms of the initial and final degradation temperatures. From the DSC results, higher glass transition temperature Tg is detected in 10% of the hardwood waste composite, and a reducing tendency of glass transition temperature Tg is observed with exceeding wood waste content. Moreover, hardwood waste at 10% demonstrated improved decomposition temperature Td, due to strong adhesion between waste and matrix.