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This study proposes a microcontroller-based closed-loop water level control system that utilizes a sonar ultrasonic sensor to monitor and regulate water levels in a tank. The system operates by continuously checking the water level in the tank and adjusting the valve’s opening and closure times to maintain the desired water level. The closed-loop control approach employed by the system offers a precise water level control solution that can significantly reduce water waste in water pumping systems. The paper also assesses the theoretical and experimental response of an open-loop water level control system. The findings demonstrate that the closed-loop system outperforms the open-loop system, indicating the effectiveness of the proposed approach in maintaining water levels in a tank. The proposed system is not only applicable to water pumping systems but can also be used to manage the flow of hot and cold water from home water heaters. Additionally, the system can be utilized in various industries that require level or flow control, with particular emphasis on the production of distilled water, juice, and milk.

Muhammad Umer, Murtaza Najabat Ali, Aamir Mubashar, Mariam Mir Biomedical Engineering & Sciences Department (BMES), School of Mechanical and Manufacturing Engineering (SMME), National University of Sciences and Technology (NUST), Islamabad, PakistanCorrespondence: Murtaza Najabat AliBiomedical Engineering & Sciences Department, School of Mechanical and Manufacturing Engineering (SMME) National University of Sciences and Technology (NUST), Sector H-12, Islamabad, PakistanTel +929 085 6053Email murtaza_bme@hotmail.comIntroduction and purpose: For the implantation of a small mechanical supporting device such as a stent, angioplasty is a more reliable technique to regain the perfusion along the heart vessel. This research work demonstrates a relative study for two different stent models during implantation in coronary artery. The purpose of this analysis was to explore the clinical efficiency of a balloon expandable stent deployment employing the finite element method.Methods: The two different models included are the Cypher Bx Velocity® (Bx_Velocity; Johnson & Johnson Corporation, New Brunswick, NJ, USA) and Savior (ST Flex Pro; National Engineering and Scientific Commission, Islambad, Pakistan). As the majority of stents are deployed using an angioplasty balloon guided by a catheter-shaft, in this study, the delivery of stents was governed by a sophisticated balloon of a trifolded pattern, attached to the catheter-shaft. This configuration has often been neglected in the past due to the complexity of interaction and the limitation of computational power.Results: The use of a trifolded semi-compliant balloon gives more promising results for quantification with experimental data available from the manufacturer’s compliance charts. This type of relative study allows us not only to improve the design of the available stent model, but also helps in probing the integrity of newly suggested models and reduces certain risks associated with the angioplasty technique. The following factors, such as stent expansion, foreshortening, dog-boning, elastic recoil, and the distribution of equivalent stresses were used to compare and improve the clinical outcome of the available stent models.Conclusion: The validation of numerical study for the Bx_Velocity stent was made with the manufacturer’s compliance chart data and for the Savior Stent with a report of experimental work data from NESCOM. Finally, some suggestions were made for good deliverability and reliability based on the above design criteria.Keywords: stent, finite element method, trifolded balloon, foreshortening, open-deployment, confined-deployment

Introduction: Tibia is the most common long bone fractured due its vulnerable subcutaneous location and most often associated with acquired complications of delayed union or non-union due to infection. Amongst the various treatment options to treat them, the Ilizarov external fixator application is considered superior due to its multiple advantages. The objective of this study was to analyse the role of Ilizarov fixation in infected tibial non-union, as well as to assess bony union and associated functional outcomes. Materials and Methods: A retrospective review was conducted for the duration between 1st January 2005 to 31st December 2016. Total of fifty-one patients with tibial non-union associated with infection who treated with the Ilizarov fixator were included in the study. Patient records were reviewed for union of bone, bone and functional outcomes and complications. Results: The most common organism for infection was identified to be Staphylococcus Aureus. At the time of final follow-up all patients had achieved union except two, one of whom had to undergo amputation due to non-union and sepsis. Majority of the patients had an excellent score as per ASAMI grading system for bone and function results. The most common complication noted was pin track infections. Conclusion: In our experience, Ilizarov external fixator is better suited for infected non-union of tibia because it can provide a stable mechanical environment, bone transport, correct deformities, and enable weight bearing and hence we recommend its use for the same.

Introduction: Ankle arthrodesis using the Ilizarov technique provides high union rate with the added benefits of early weight-bearing, and the unique advantage of its ability to promote regeneration of soft tissue around the bone, including skin, muscle and neuro-vascular structures, and its versatility to allow correction of the position of the foot by adjusting the frame post-operatively as needed. We describe our experience with this technique and the functional outcomes in our patients. Materials and Methods: This retrospective study was conducted in 20 ankle fusion cases using the Ilizarov method between the years 2007 and 2017. We defined success in treatment by loss of preoperative symptoms and radiological union on plain radiographs of the ankle. Results: Fusion was achieved in all patients (100%). Immediate post-operative ambulation was with full weight bearing (FWB) in 16 (83%) of the participants and non-weight bearing (NWB) in 3 patients (17%). Postprocedure 11 patients (67%) of the participants who were full weight bearing required some form of support for walking for 2-3 weeks. Post-operatively three patients had pin tract infection requiring intravenous antibiotics. Radiological union took range of 6-12 weeks, mean union time was 8 weeks. Only one patient required bone grafting due to bone loss. Average follow-up period was 10-45 months. Conclusion: The Ilizarov technique has a high union rate and leads to general favourable clinical outcome and may be considered for any ankle arthrodesis but is especially useful in complex cases such as for revisions, soft-tissue compromise, infection and in patients with risk for non-union. Early weight bearing is an extra benefit.

Isolated cerebrospinal fluid (CSF) rhinorrhoea as a sole presenting symptom of idiopathic intracranial hypertension (IIH) is extremely rare. IIH typically presents with headache, pulsatile tinnitus, dizziness, nausea, vomiting, and visual disturbance. We report two cases which presented with acute onset spontaneous CSF rhinorrhoea without any other symptom. In addition, we discuss in detail imaging features of IIH with review of its literature.

Dead space fraction (Vd/Vt) measurement performed using volumetric capnography requires arterial blood gas (ABG) sampling to estimate the partial pressure of carbon dioxide (PaCO2). In recent years, transcutaneous capnography (PtcCO2) has emerged as a noninvasive method of estimating PaCO2. We hypothesized that PtcCO2 can be used as a substitute for PaCO2 in the calculation of Vd/Vt. In this prospective pilot comparison study, 30 consecutive postcardiac surgery mechanically ventilated patients had Vd/Vt calculated separately using volumetric capnography by substituting PtcCO2 for PaCO2. The mean Vd/Vt calculated using PaCO2 and PtcCO2 was 0.48 ± 0.09 and 0.53 ± 0.08, respectively, with a strong positive correlation between the two methods of calculation (Pearson’s correlation = 0.87, p

In this study, we fabricated and studied properties of ternary polymer blends containing polylactic acid (PLA), polypropylene (PP), and acrylonitrile-butadiene-styrene (ABS). The melt rheology experiments showed that the present combination (PLA/PP/ABS) exhibited a melt process-ability, which is comparable to those of individual components. The ternary blends prepared in this work can be exploited to fabricate hierarchically porous PLA materials for biomedical applications., INTRODUCTION Increasing concerns over the environmental impact and sustainability of conventional polymer materials have motivated academic and industry to devote considerable efforts to the development of polymers from renewable resources. [...]

In this study, cubic Hastelloy-X was manufactured by laser powder bed fusion process. A systematic investigation focused on the microstructure and anisotropic electrochemical corrosion behavior along the building direction was conducted. Distinctive columnar dendritic features across melt pool boundaries were consistently observed in the top (HX-T), middle (HX-M), and bottom (HX-B) regions along the building direction. A significant reduction in Mo content from the HX-T to the HX-B was observed, attributed to preferential segregation of Mo during the solidification process. Typical fish-scale molten pool was observed in the HX-B and HX-M, while HX-T consisted of strip molten pool in addition to fish scale molten pool. All samples showed the typical characteristics of Goss texture //BD. HX-M sample showed the largest grain size, highest intensity ∼6.35 mrd and lowest kernel average misorientation value as compared to HX-T and HX-B associated with the remelting of the former solidified layer due to the newly deposited layer. Electrochemical analysis including electrochemical impedance spectroscopy and potentiodynamic polarization scans were conducted in 10 wt% NaCl electrolytes at constant temperature of 25 ± 1 °C. HX-T showed the lowest corrosion rate as compared to HX-M, HX-B (0.55, 23.16 and 16.01 mpy for HX-T, HX-M and HX-B, respectively). The surface morphology of corroded samples revealed that the formation of a compact passive film due to the presence of high atomic % of Mo in HX-T restricted the chloride ions from the electrolyte to penetrate and react with the metal samples subsequently enhancing the corrosion resistance.

This study investigates the influence of extrusion and deformation temperatures on the mechanical properties of the AZ61 Mg alloy. Increasing the extrusion temperature from 300 to 400 °C led to larger grain size and higher basal texture intensity. At 400 °C, the AZ61 alloy exhibited more Al–Mn phases and fewer Mg17Al12 phases, indicating enhanced dissolution of Mg17Al12 in the α-Mg matrix. Uniaxial tensile tests were conducted at room temperature (RT) and cryogenic temperature (CT, −150 °C). Despite grain growth, a higher yield strength (YS) was achieved at higher extrusion temperatures due to the texture-strengthening mechanism. However, during deformation at CT, the higher YS was primarily attributed to the formation of multiple twinning within individual grains, causing twinning interactions. These twin-interacting boundaries create additional barriers to dislocation movement. Notably, the AZ61 sample extruded at 400 °C demonstrated the formation of stacking faults during deformation at CT, with dislocations accumulating around the faults. This contributed to the best strength without compromising ductility in this sample.

The study aims to determine the influence of behavioural biases on financial risk propensity. It also attempts to examine the influence of financial risk propensity on investment decisions and the mediational role of financial risk propensity on the relationship between behavioural biases and investment decisions. A survey by questionnaire method is adopted to collect data from 203 respondents using the purposive sampling technique among the investors. The study has found that prospect, herding, and heuristics dimensions of behavioural bias have a significant impact on financial risk propensity, and in turn, financial risk propensity has a significant impact on investment decisions. The results of the study can help to develop more realistic investment valuation models in light of the revised risk-return expectations of investors who act contrary to the traditional concept of rational utility maximisers.

This study investigates the influence of CaO (0.5, 1 (wt.%)) alloying on the microstructural evolution, texture development and deformation behavior of AZ61 magnesium alloy. The uniaxial tension tests at room (RT) and cryogenic (CT, -150 °C) temperature were performed to investigate the twinability and dislocation behavior and its consequent effect on flow stress, ductility and strain hardening rate. The results showed that the AZ61-1CaO exhibited superior strength/ductility synergy at RT with a yield strength (YS) of 223 MPa and a ductility of 23% as compared to AZ61 (178 MPa, 18.5%) and AZ61-0.5CaO (198 MPa, 21%). Similar trend was witnessed for all the samples during CT deformation, where increase in the YS and decrease in ductility were observed. The Mtex tools based in-grain misorientation axis (IGMA) analysis of RT deformed samples revealed the higher activities of prismatic slip in AZ61-CaO, which led to superior ductility. Moreover, subsequent EBSD analysis of CT deformed samples showed the increased fraction of fine {10-12} tension twins and nucleation of multiple {10-12} twin variants caused by higher local stress concentration at the grain boundaries, which imposed the strengthening by twin-twin interaction. Lastly, the detailed investigations on strengthening contributors showed that the dislocation strengthening has the highest contribution towards strength in all samples.

In the pursuit of enhancing the mechanical properties of magnesium alloys, particularly AZX211, which is renowned for its lightweight characteristics but plagued by low ductility and strength, this study explores the effects of cryogenic pre-stretching at −170 °C. The research reveals that cryogenic pre-stretching triggers the formation of a complex twinning network comprising thin tension twin {10–12} lamellas and multiple twin variants, significantly improving both strength and ductility in the material. The enhanced ductility is attributed to the activation of the prismatic slip system due to texture reorientation, as confirmed by Schmid factor criteria and in-grain misorientation axes (IGMA) analysis.

Within the family Fabaceae, the genus Glycine is composed of two subgenera annuals (2n=40) and perennials. This life strategy transition may have differentially affected the evolution of various gene families. Its cultivated species G. max has high level of susceptibility to major pathogens including viruses, bacteria and fungi. Understanding nucleotide-binding domain leucine-rich repeat (NLR) genes evolution in soybean is of paramount importance due to their central role in plant immunity and their potential in improving disease resistance in soybean cultivars. In this study, we investigated the significance of this annual-perennial transition on the macroevolution of NLR genes in the genus Glycine. Our results reveal a remarkable distinction between annual species such as Glycine max and Glycine soja, which exhibit an expanded NLRome compared to perennial species (G. cyrtoloba, G. stenophita, G. dolichocarpa, G. falcata, G. syndetika, G. latifolia and G. tomentella). Our evolutionary timescale analysis pinpoints recent accelerated gene duplication events for this expansion, which occurred between 0.1 and 0.5 million years ago, driven predominantly by lineage-specific and terminal duplications. In contrast, perennials initially experienced significant contraction during the diploidisation phase following the Glycine-specific whole-genome duplication event (~10 million years ago). Despite the reduction in the NLRome, perennial lineages exhibit a unique and highly diversified repertoire of NLR genes with limited interspecies synteny. The investigation of gene gain and loss ratios revealed that this diversification resulted from the birth of novel genes following individual speciation events. Among perennials, G. latifolia, a well-known resistance resource, has the highest ratio of these novel genes in the tertiary gene pool. Our study suggests evolutionary mechanisms, including recombination and transposition, as potential drivers for the emergence of these novel genes. This study also provides evidence for the unbalanced expansion of the NLRome in the Dt subgenome compared with the At subgenome in the young allopolyploid G. dolichocarpa. To the best of our knowledge, this is the first study to investigate the effect of annuality and perenniality life transition on the evolution of NLR genes in the genus Glycine to identify its genomics resources for improving the resistance of soybean crop with global importance on the economy and food security.