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The human nasal cavity develops from birth with size anatomical changes. This study aims to evaluate the flow parameters and particle deposition parameters. Neonatal and infant nasal cavities are developed using MIMICS 21.0, and the flow is evaluated by ANSYS 2021 R2 using CFD to evaluate velocity, pressure, micro- and nanoparticle depositions under sedentary breathing conditions. Neonatal nasal valve velocity was recorded 3.5 times higher compared to the infant for 1.8 LPM and 2.7 times for 3 LPM. Neonatal vestibular depositions up to 10 µm were 6.6%, which increased to 76% for 60 µm for 1.8 LPM and increased to 21.3% for 10 µm and 79% for 60 µm for 1.8 LPM. The neonatal nasal valve showed maximum depositions of around 35% for 20 µm for both flow rates. Maximum depositions of nanoparticles are in the mid-nasal region. Infant nasal cavities deposit around 1% to 2% for nanoparticles below 20 nm for both flow rates. Neonatal overall microparticle depositions doubled with an increase in flow rate up to 10 µm. The overall deposition efficiency of nanoparticles increases 1.5 times with increasing flow rate. This study will help with the medical administration of aerosol-based medications in the patient and age-specific nasal cavity. [ABSTRACT FROM AUTHOR]

The selection of abrasive material and parameters of the Air-Abrasion device for a particular application is a crucial detail. However, there are no standard recommendations or manuals for choosing these details; the operator must depend on his experience and knowledge of the procedure to select the best possible material and set of parameters. This short review attempts to identify some of the effects that the selection of material and parameters could have on the performance of the Air-Abrasion procedure for a particular application. The material and parameter data are collected from various studies and categorized according to the most popular materials in use right now. These studies are then analyzed to arrive at some inferences on the performance of Air-Abrasion materials and parameters. This review arrives at a few conclusions on the effectiveness of a material and parameter set, and that there is potential for developments in the area of standardizing parameter selection; also, there is scope for further studies on Bio-Active Glass as an alternative to the materials currently used in Air-Abrasion. [ABSTRACT FROM AUTHOR]

Objective: The nasal cavity effectively captures the particles present in inhaled air, thereby preventing harmful and toxic pollutants from reaching the lungs. This filtering ability of the nasal cavity can be effectively utilized for targeted nasal drug delivery applications. This study aims to understand the particle deposition patterns in three age groups: neonate, infant, and adult. Materials and methods: The CT scans are built using MIMICS 21.0, followed by CATIA V6 to generate a patient-specific airway model. Fluid flow is simulated using ANSYS FLUENT 2021 R2. Spherical monodisperse microparticles ranging from 2 to 60 µm and a density of 1100 kg/m3 are simulated at steady-state and sedentary inspiration conditions. Results: The highest nasal valve depositions for the neonate are 25% for 20 µm, for infants, 10% for 50 µm, 15% for adults, and 15% for 15 µm. At mid nasal region, deposition of 15% for 20 µm is observed for infant and 8% for neonate and adult nasal cavities at a particle size of 10 and 20 µm, respectively. The highest particle deposition at the olfactory region is about 2.7% for the adult nasal cavity for 20 µm, and it is <1% for neonate and infant nasal cavities. Discussion and conclusions: The study of preferred nasal depositions during natural sedentary breathing conditions is utilized to determine the size that allows medication particles to be targeted to specific nose regions. [ABSTRACT FROM AUTHOR]

Renal transplantation is the treatment of choice for improved survival and quality of life in patients with end-stage renal disease. However, perirenal fluid collections are common surgical complications after renal transplant, with about 0.6 to 18% of patients developing a lymphocele. Conventional treatments include percutaneous aspiration and drainage, laparoscopic fenestration, and open surgical decompression stepwise. Recently, a new image-guided percutaneous transperitoneal balloon fenestration technique has been described as an alternative to the laparoscopic or surgical technique. We present the case of a 25-year-old male patient diagnosed with a lymphocele after 2 months of transplantation and no resolution of the lymphocele with percutaneous aspiration and drainage. We used this new technique under ultrasound and fluoroscopy guidance, which resulted in the resolution of the lymphocele at 1 month postprocedure. This case report highlights this new technique's potential role in successfully managing the posttransplant lymphocele in a minimally invasive manner. [ABSTRACT FROM AUTHOR]

Aim and background: Maternal mortality is one of the nightmares for obstetricians and also for the patient's family. There are many causes, but disseminated intravascular coagulation (DIC) with acute renal failure is one of the challenging cases, which requires a multidisciplinary approach. Case description: A 29-year-old second para patient with two live births, was presented in the emergency department with septic shock and DIC. She had gross hemoperitoneum with massive rectus sheath hematoma. Initially her blood pressure was stabilized by giving blood products and supportive treatment. As soon as her blood pressure became stable, she underwent computed tomographic angiography-guided embolization of right inferior epigastric artery. After 24 hours of embolization, she underwent laparotomy for abdominal compartment syndrome. Conclusion: Although primary treatment of DIC is to treat underlying cause, but transarterial embolization in addition to primary treatment, is also equally effective in controlling the on-going bleeding which in turn results in DIC. Clinical significance: Maternal mortality represents health state of a country and one should try to be safe as many near miss as possible with a multidisciplinary approach. [ABSTRACT FROM AUTHOR]

The transmission mechanism of artificial flapping-wing drones generally needs low weight and the fewest interconnecting components, making their development challenging. The four-bar Linkage mechanism for flapping actuation has generally been used till now with complex and heavy connecting designs, but our proposed novel perpendicularly organized 3-cylindrical joint mechanism is designed to be unique and lighter weight with smooth functioning performance. The proposed prototype transforms the rotary motion of the motor into a specific angle of flapping movement, where the dimensions and specifications of the design components are proportional to the obtained flapping angle. Power consumption and flapping actuation can be monitored by adjusting the motor's rotational speed to control the individual wing in this mechanism. The proposed mechanism consists of a crank with three slightly slidable cylindrical joints perpendicularly arranged to each other with a specified distance in a well-organized pattern to produce a flapping movement at the other end. In order to examine the kinematic attributes, a mathematical process approach is formulated, and kinematic simulations are performed using SIMSCAPE multibody MATLAB, PYTHON programming and COMPMECH GIM software. The proposed invention's real-time test bench prototype model is designed, tested and analyzed for flapping validation. [ABSTRACT FROM AUTHOR]

The airflow behaviour and particle deposition before and after the maxillary expansion are evaluated using the computational fluid dynamics method. A pediatric patient was subjected to maxillary expansion and the CT scans of pre and post were recorded. The procured CT scans were developed into 3D models using Materialise MIMICS 21.0 (Materialise, Ann Arbor, MI). The analysis was performed using ANSYS FLUENT 2020 R2 with three different flow rates defined at the nostril inlet as 5, 10, and 15 LPM. The surface area and nasal volume increased by 5.1% and 16.5%, respectively, for the post-maxillary expansion case. The velocity profiles show a maximum value at the nasal valve regions followed by a decreased velocity in the mid-nasal region with an 85% lower velocity observed at the nasal valve for the post-maxillary expansion case. The nasal resistance and pressure drop decrease by 46% to 66% in post-maxillary expansion cases. The maximum WSS at the nasal valve region is observed which is reduced by around 47% for postmaxillary expansion cases. Particle deposition studies show a reduction in particle depositions in post cases indicating a greater number of inhaled particles reaching the lungs. The pressure drop and the nasal resistance values were reduced by more than 50% for post-maxillary expansion. The particle deposition studies show increased depositions at higher flow rates for both cases. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Insect RoboFlyers are interesting and active focuses of study but producing high-quality flapping robots that replicate insect flight is challenging., due to the dual requirement of both a sophisticated transmission mechanism with light weight and minimal intervening connections. This innovative mechanism was created to address the need for a producible structure that is small in size, small in mass, and has reduced design linkages. The proposed Single Crank-Slotted Dual Lever (SC-SDL) mechanism transforms rotational motion into specific angular motion at different velocities for each of its two strokes, i.e., the forward stroke and the return stroke. The discovery of a lag between the left and right lever motions in our design mechanism-I leads us to the conclusion that the flapping is asymmetric. To eliminate the position lag, the design has been altered, and a new design mechanism-II has been developed. Comparative kinematic analysis of both design systems is performed using simulations. Two-dimensional analysis of the base ornithopter configuration using ANSYS FLUENT yielded deeper insights regarding the influence of varying flapping frequency on critical flow metrics regarding adequate lift and thrust. For a flapping frequency of 24 Hz, adequate lift generation was achieved with minimal flow disturbances and wake interactions. Averaged dual wing estimations were made as part of the CFD study, which showed similar agreements. To validate the estimations, experimental tests were performed over the design mechanism-II configuration. [ABSTRACT FROM AUTHOR]

In this work, a biologically active curcumin molecule is used as an antibacterial agent, and the insertion of this naturally occurring biomolecule into the backbone of water-dispersible polyurethane has been successfully achieved to synthesize bio-based antibacterial textile finishes. These curcumin-based water-dispersible polyurethane (CUR-WDPU) dispersions were prepared by utilizing isophorone diisocyanate (IPDI), polyethylene glycol (PEG), dimethylolpropionic acid (DMPA) and triethylamine (TEA) following the prepolymer mixing process by incorporating variable molar quantities of curcumin (CUR). Structure elucidation of synthesized CUR-WDPU dispersions was obtained through Fourier transformed infrared spectroscopy (FTIR) which confirmed the insertion of CUR into the WDPU backbone. Using the pad-dry-cure procedure, the varying varieties of plain weave polyester/cotton blended dyed and printed textile samples were treated with synthesized CUR-WDPU finishes. The antibacterial activities of these treated textiles have been assessed, and the outcomes revealed that the insertion of curcumin into the PU polymer chain has significantly boosted the antibacterial activities of PU dispersions. These newly prepared CUR-WDPUs dispersions are proved to be eco-friendly antimicrobial finishes because these are containing natural bioactive agents such as curcumin, showing potential antibacterial applications on polyester/cotton textiles. Predominantly, this research work is an attempt toward the greener approach of novel bio-based finishing materials preferably useful for textile diligences. Future investigations of these finishes will explore the other textile assets of poly-cotton textiles without adversely influencing their color fastness and mechanical properties. [ABSTRACT FROM AUTHOR]

This research is aimed at synthesizing some novel bio-based ecofriendly finishes for textile applications. A series of curcumin based aqueous polyurethane (PU) dispersions (CUR-WDPU-IPDI) was prepared using polyethylene glycol (PEG), isophorone diisocyanate (IPDI) and dimethylolpropanoic acid (DMPA) via conventional pre-polymer process. The dual functionality is incorporated by hindering the polyurethane pre-polymer with isocyanate (-NCO) groups and curcumin was utilized to extend the polymeric chain to achieve the CUR-WDPU-IPDI dispersion. Structural characteristics of the synthesized polymer were investigated by Fourier Transform Infrared (FT-IR) spectrophotometer. The performance of PU dispersions for increasing the color fastness properties (washing, rubbing and perspiration fastness) of plain weave fabrics (poly/cotton, dyed and printed) was studied. Furthermore, the mechanical strength (pilling, tearing and tensile strength) of the said fabric (dyed, printed and white) was also evaluated. Results clearly exhibited that the color fastness properties and mechanical strength of the dyed, printed and white fabrics were improved significantly after treating with the PU finishes. These synthesized curcumin-based water dispersible polyurethanes (CUR-WDPU-IPDI) finishing agents are greener products which are particularly derivatized from bio-resources. Owing to their biocompatibility, copious availability, less noxious, greener methodology and ecofriendly nature, these can be utilized as attractive ecofriendly alternatives for textile applications. [ABSTRACT FROM AUTHOR]

Cerebral intracranial aneurysms are serious problems that can lead to stroke, coma, and even death. The effect of blood flow on cerebral aneurysms and their relationship with rupture are unknown. In addition, postural changes and their relevance to haemodynamics of blood flow are difficult to measure in vivo using clinical imaging alone. Computational simulations investigating the detailed haemodynamics in cerebral aneurysms have been developed in recent times not only to understand the progression and rupture but also for clinical evaluation and treatment. In the present study, the haemodynamics of a patient-specific case of a large aneurysm on the left side internal carotid bifurcation (LICA) and no aneurysm on the right side internal carotid bifurcation (RICA) was investigated. The simulation of these patient-specific models using fluid–structure interaction provides a valuable comparison of flow behavior between normal and aneurysm models. The influences of postural changes were investigated during standing, sleeping, and head-down (HD) position. Significant changes in flow were observed during the HD position and quit high arterial blood pressure in the internal carotid artery (ICA) aneurysm model was established when compared to the normal ICA model. The velocity increased abruptly during the HD position by more than four times (LICA and RICA) and wall shear stress by four times (LICA) to ten times (RICA). The complex spiral flow and higher pressures prevailing within the dome increase the risk of aneurysm rupture. [ABSTRACT FROM AUTHOR]

Endometriosis is a common benign and chronic inflammatory gynaecological disease due to functional endometrial glands and stroma in an ectopic location outside the uterine cavity. It affects 5-10% of reproductive age group women in the peak age of 24-29 years. However, women with infertility and chronic pelvic pain have an even greater prevalence, accounting for 30-50% and 90% of cases, respectively. Although it is a common entity, patients often get a delayed diagnosis because it is often subtle (hidden), missed, or confused with mimics, leading to misdiagnosis, which significantly affects patients’ quality of life because they live in constant pain from undiagnosed endometriosis. Laparoscopy followed by histopathological confirmation is the gold standard for diagnosis, but it is an invasive procedure. MRI is an excellent non-invasive modality that helps in non-invasive diagnosis, with excellent delineation of the disease extent, and thus provides a presurgical mapping of the disease, which is helpful for the operating surgeon. Radiologists should be aware of all possible spectrum and diagnose this early and provide a detailed structured report mapping the entire extent of the disease process, which helps in effective treatment planning and successful outcomes in improving patients’ quality of life. [ABSTRACT FROM AUTHOR]

The total hip prosthesis is considered one of the greatest advancements in orthopaedic surgery in the early 20th century. In hip implant replacement, the stem is inserted into the femur and femoral head, acetabular cup, and backing cup over the stem. This felicitates the normal range of motion and stability of an individual compared to the natural hip joint. Several different types of biomaterials are used in the total hip prosthesis. Where the combination of UHMWPE, CoCrMo alloy, and Ti-6Al-4 V alloy is widely used due to their superior mechanical properties over the others. In this work, these material combinations are used for the analysis with changes in the femoral head sizes from 24 mm to 48 mm to know the best size with the better material combination. Static structural analyses are carried out using Ansys R-19. Two sets of analyses are performed for two different material combinations between Ti6Al-4 V, CoCr, and UHMWPE. The circular cross-shaped stem with change in femoral head sizes from 24 mm to 48 mm is used for analysis. The acetabular cup and backing cup thickness are kept constant throughout the study. The size of the acetabular cup and backing cup is considered 6 mm and 4 mm respectively. Loading and boundary conditions are considered as per the ASTM standards. Hip implant with Ti-6Al-4 V for stem and a 4 mm backing cup of CoCr and 6 mm acetabular cup of UHMWPE shown the least stress value of 203.48 MPa over all the other models which are used in the analysis. This work shows the analysis to know the effect of the change in femoral head size and also the change in material combinations used in hip implants. Further experimental work can be carried out to validate the results obtained in the current work. [ABSTRACT FROM AUTHOR]

In replacement surgery of the hip joint, an implant is replaced into the natural femur which recreates the articulation and functionally of a natural joint. Total hip replacement is significantly increasing by the day worldwide and is likely to increase by 174% by 2030. Primary revision is another major concern for total hip replacement with revision rates likely to increase by 137%. The first part of the article states the basic anatomy of the hip joint, different ligaments in the hip, the disorders associated with the joint, and evaluation of total hip arthroplasty. In the second part some of the major works are highlighted followed by a detailed discussion about different design considerations and wear-related issues in hip joints. More emphasis is given to the tribological behavior of implants under different conditions. The design aspects and several parameters which affect the wear rate in implants are summarized. Also, different testing methods which are used both in experimental and numerical techniques are reported to estimate the wear rates in hip implants with the evolution of hip implants since the early 20th century, in terms of different designs, materials and wear hip implant arthroplasty is known as one of the best advancements in healthcare. Further research is needed to establish to improve the life expectancy of hip implants. [ABSTRACT FROM AUTHOR]

The Li-ion batteries used in electric vehicles widely employ cooling plates with mini channels for thermal management purpose. Researches on battery thermal management systems of electric vehicles are largely focused on improving the cooling efficiency hence obtaining temperature uniformity across the cells. In the present work, a streamline configuration has been incorporated in cooling plate design to enhance the performance of mini-channel cooling plate. These kinds of configurations are usually found in submarine and aerospace applications. By adopt- ing streamline design the flow resistance is found to reduce. Five plates with different number of channels (3, 4, 5, 6, 7) were computationally studied at a coolant (water and ethylene glycol mixture) flow rate of 0.002 kg/s. The maximum cell temperature is decreased by 7.8% for 7-channel configuration. Temperature uniformity is also found to improve using this design. The results reveal that this design is able to maintain the temperature of Li-ion battery in safe operating range. Hence this could be a better solution for thermal management of Li-ion batteries in future. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel green series of hydroxyethyl cellulose (HEC) based polyurethane (PUs) prepolymersblended with TiO2 nanoparticles were synthesized by reaction of Isophorone diisocyanate (IPDI), hydroxyl-terminated polybutadiene (HTPB), and hydroxyethyl cellulose (HEC). The chain was further extended with 1,4-butanediol (BDO) to get final HEC based polyurethane bio nanocomposites (FPUNC). A mixture of HEC based polymer and TiO2 nanoparticles was formed in solution polymerization, in which the TiO2 nanoparticles dispersed depending on interaction of TiO2 nanoparticles with polymer chains. The molecular structure of the synthesized PU bionanocomposites was confirmed by FTIR. A series of FPUNCs was prepared by varying the percent composition of the TiO2 nanoparticles into the PU matrix. The morphology of the bionanocomposites was carried out by X-ray diffraction (XRD) studies and scanning electron microscopy (SEM). SEM images verified the good dispersion of TiO2 nanoparticles into PU matrix. The thermal stability of the synthesized FPUNCs was done by thermal gravimetric analysis (TGA), and the FPUNC12 with 5% contents of TiO2 nanoparticles showed better thermal stability. The resultant HEC-TiO2 based FPUNCs material have promising bio-degradable and bio functional materials with good thermal properties and have potential applications in the field of biomaterials. [ABSTRACT FROM AUTHOR]

The novel coronavirus responsible for COVID-19 has spread to several countries within a considerably short period. The virus gets deposited in the human nasal cavity and moves to the lungs that might be fatal. As per safety guidelines by theWorld Health Organization (WHO), social distancing has emerged as one of the major factors to avoid the spread of infection. However, different guidelines are being followed across the countries with regards to what should be the safe distance. Thus, the current work is an attempt to understand the virus deposition pattern in the realistic human nasal cavity and also to find the impact of distance that could be termed as a safety measure. This study is performed usingComputationalFluid Dynamics as a solution tool to investigate the impact of COVID-19 deposition (i) On a realistic 3D human upper airway model and (ii) 2D social distancing protocol for a distance of 0.6, 1.2, 1.8, and 2.4 m. The results revealed that the regional deposition flux within the nasal cavity was predominantly observed in the external nasal cavity and nasopharyngeal section. Frequent flushing of these regions with saltwater substitutes can limit contamination in healthy individuals. The safe distancing limit estimated with 1 m/s airflow was about 1.8 m. The extensive deposition was observed for distances less than 1.8 m in this study, emphasizing the fact that social distancing advisories are not useful and do not take into account the external dynamics associated with airflow. [ABSTRACT FROM AUTHOR]

Fossil fuel is currently the major source of energy but it is a fast depleting resource. The phenomenal increase in fossil fuel consumption over recent times has adversely affected our carbon footprint, severely impacting the environment. With strict environmental regulations in place, the focus towards renewable sources of energy is gaining momentum, supported by recent advancements in technologies in wind, hydro and solar. Wind energy was the first form of clean energy and has seen a major increase in power production. However, site restrictions limit the wind turbine from being used to its maximum potential. In recent years, the concept of some unconventional methods have been proposed. In this review, various types of wind turbines are discussed with their recent advances and depicting the challenges faced related to various aspects. The review contains details mainly about 4 types of wind turbines, i.e. floating offshore wind turbines, airborne wind turbines, highway wind turbine systems, and locomotive mounted wind turbines. [ABSTRACT FROM AUTHOR]

Recent industrial revolutions cause bauxite mining activities across the globe to become notably more active. However, ceasing bauxite mining activities left bauxite mining sites barren without any vegetation, causing environmental and health problems, such as dust and red muds. Existing remediation techniques such as physical separation, incineration and chemical precipitation may increase risks of additional contamination or be more costly; thus, there is a need for greener and more feasible method such as phytoremediation. Phytoremediation and revegetation may help to make the barren lands to become green again with lower costs. Researches on phytoremediation technique to solve environmental problems in Malaysia are still limited but show great potentials. Works and researches on phytoremediation for rehabilitating bauxite-mined sites has been successfully conducted across the world, showing promising futures for barren bauxite mining sites in Malaysia. This study summarizes the general scenario of bauxite mining activities and the potential of phytoremediation, focusing on reclamation of bauxite-mined lands. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hip implants consist of a stem, femoral head, acetabular cup, and backing cup. There is a wide variety of sizes and lengths. Their adaptability is limited because of the inter-anatomical variations. There is no single fit-for-all implant design that satisfies the orthopedic requirement satisfactorily. In this work, the trapezoidal-shaped stem with three different cross-sections is considered. The femoral head size, acetabular cup thickness, backing cup thickness, and trunnion geometry were varied to arrive at the best possible combination. ANSYS R-19 was used to perform the static analysis. It is found that trapezoidal-shaped profile two has the least amount of stress and total deformation. The von Mises stresses were found to be higher when the femoral head size was between 32 mm to 40 mm in profile two. It was also observed that the femoral head with 24 mm has the least stress compared to higher head sizes. The maximum von Mises stress-induced in profile two was 141.0 MPa, the total deformation of 0.04436 mm and elastic strain of 7.6 × 10−4 mm/mm. Trunnion interface does not have a significant role with respect to the structural strength of the implant. From the findings of this study, it is inferred that profile two shaped stems with the femoral ball size of 36 mm, acetabular cup thickness of 2 mm and backing cup thickness of 1mm is best suited for the hip replacement. The major outcome of this study is the utilization of the DoE method to determine the optimized value of the implant. [ABSTRACT FROM AUTHOR]

Polydimethylsiloxane belongs to a polymeric organosilicon compounds that is widely used as silicon-based organic polymer. Polydimethylsiloxane is a basically optically clear, inert, nontoxic and inflammable material which is widely used in medical devices, as an elastomer, antifoaming agent, heat-resistant lubricants, fire retardants, in cosmetics and for other valuable domestic applications. This comprehensive review of polydimethylsiloxane describes synthesis, characterization, surface modifications and formation of vital biodegradable films/membranes that can facilitate improvements in modern research. Polydimethylsiloxane is viscoelastic, hydrophobic, cytocompatible and herbicidal penetrant that provides water-repellent coatings in textile industry. In this study, copolymers of polydimethylsiloxane were thoroughly studied based on polyimides, carboxyesters, hydroxyethyleneoxide, degradation with polystyrene, cross-linking with block copolymers, phosphorus-based, gelatin-based and polyurethanes, which can be used for modern manufacturing purposes in all kinds of industrial world. [ABSTRACT FROM AUTHOR]

In this work, a 3D urinary bladder was subjected to various pressure loading conditions mimicking the bladder filling volume. The bladder layer consisting of adventitia, detrusor and mucosa layer having different mechanical properties produced different deformation and stresses when subjected to the varying loads. The volume of the bladder changed to 231.34 ml which was 128.91% higher than the assumed initial volume of 50 ml on application of 18 kPa of pressure. The detrusor layer which is thickest of the bladder wall reduced to 1.312 mm from 4.4 mm, recording a 108% change in its thickness at 18 kPa pressure. The maximum von-Mises stress obtained were significantly higher in case of the Mucosa layer when compared to the detrusor and adventia layer. The unique layup of the bladder wall having different properties plays a major role in sustaining adverse pressure gradients and absorbing high stresses. [ABSTRACT FROM AUTHOR]

Natural products with therapeutic nature are nowadays warmly welcomed in textiles. Current study is concerned with isolation of tannin from neem bark (Azadirachta indica) and its application onto silk fabric. For improvement in shades, chemical & bio-mordants have been employed at optimal dyeing conditions. It is found that methanolic extract of pH 5 obtained 8 g dye powder after US Treatment for 30 min has given high color strength if used to dye irradiated silk for 65 min at 75 °C. Bio-mordanting using herbal plants has improved the color characteristics as compared to chemical mordants used. ISO standards for color fastness reveal that herbal based bio-mordants have improved the rating from good to excellent as compared to chemical mordants used. It is concluded that US treatment has not only isolate the colorant for neem bark under mild condition but also given excellent characteristic using bio mordants onto silk fabrics. [ABSTRACT FROM AUTHOR]

This research aims to investigate the airflow patterns and particle deposition in a healthy human upper airways. A realistic 3-D computational model of the upper airways including the vestibule was developed using a series of CT scan images of a healthy human. Simulations of the airflow fields in the upper airway passages were performed by solving the Navier-Stokes and continuity equations for breath rate 20 L/min. The trajectory analysis approach was applied to study the particle transport and deposition for the model with and without mucous lining. The presented results revealed that the mucous layer can have significant impact on airflow analysis and there were noticeable differences in the amount of particle deposition in each models. [ABSTRACT FROM AUTHOR]

Environmental pollution spread due to frequent use of synthetic dyes has compelled the global community to move toward sustainable and eco‐friendly products. The present research has been conducted to investigate the coloring efficacy of Arjun bark (Terminalia arjuna) for silk fabric under the influence of ultrasonic radiation. Extracts have been prepared in different media and extracts and silk fabrics have been irradiated ultrasonically for 15–60 min at 60 °C. Good color strength is obtained, by dyeing irradiated silk for 65 min at 65 °C, when irradiated extract of pH 3 (RE, 30 mL) obtained from powder (6 g) is used in the presence of salt concentration of 3 g/100 mL. Pre‐chemical mordants such as 5% of Al (Aluminum sulphate) and 9% of Fe (iron sulphate) as well as post‐chemical mordants such as 5% Al (Aluminum sulphate) and 3% of Fe (iron sulphate) have improved the color characteristics. The bio‐mordants employed reveal that 9% of pomegranate and turmeric extracts as pre and post bio‐mordants have given excellent coloring characteristics. It is concluded that Arjun bark has a great potential to act as a source of natural colorant for silk dyeing under the influence of ultrasonic radiation. © 2018 American Institute of Chemical Engineers Environ Prog, 38: S331–S339, 2019 [ABSTRACT FROM AUTHOR]

As the use of high performance textiles has grown, the need for chemical finishes to provide the fabric properties required in the special applications has grown accordingly. In this project, a series of water dispersible polyurethanes dispersion (CS-PUs) with multipurpose performance profile was developed using isophorone diisocyanate (IPDI), polyethylene glycol (PEG), 2,2-dimethylol propionic acid (DMPA) and chitosan (CS) for textile applications. In two step synthesis process, NCO functional PU prepolymers prepared by reacting IPDI, PEG, and DMPA were extended with varying molar quantities of chitosan followed by structural characterization through FTIR. The prepared CS-PU dispersions were applied onto the dyed and printed poly-cotton blend fabrics. The performance behavior of the treated fabric in terms of crease recovery, tear strength, tensile strength, and antibacterial properties was evaluated by applying standard test methods. These investigations show that the CS-PU dispersions can be applied as antibacterial textile finishes with significant improvement in the physical and mechanical properties of poly-cotton fabrics. [ABSTRACT FROM AUTHOR]

This study presents, use of a technique based on functional imaging and Computational Fluid Dynamics (CFD) modeling in generating useful data that can be used to determine and diagnose Obstructive Sleep Apnea (OSA) condition. A three-dimensional nasal cavity model was reconstructed based on computed tomographic images of a healthy Malaysian adult nose. Navier-Stokes and continuity equations for steady airflow were solved numerically to examine inspiratory and expiratory nasal flow. The study showed that, the pressure drop from the choanae to the OSA region was found to be larger than the pressure drop through the nasal passages. Stresses as high as 42.4 Pa were observed in this constricted OSA passageway, which is otherwise not a common occurrence in the normal subjects. [ABSTRACT FROM AUTHOR]

Curcumin (CUR) has been investigated for its poor accessibility to a site of action or absorption and rapid metabolism to cope with the limited medication and cure applications. This article reviews numerous approaches, such as encapsulated surfactant/polymeric micelles, liposomes, micro/nano-spheres, nano-suspensions/composites, nanocomplex, films, and hydrogels for effective transfer of CUR to target sites. Chitosan (CS), and chitosan derivatives have been found to enhance therapeutic efficacy of CUR. CS/modified-CS based alginate, cyclodextrin, starch, dextran sulfate, ZnO, phytosomes, and poly(butyl) cyanoacrylate drug delivery matrices improved bioavailability, prolonged drug loading and permeability, sustained release rate, improved solubility and stability (prevent metabolic degradation) of CUR, consequently promoting various clinical applications. CS based polysaccharide, protein, and metal oxide drug delivery nano formulations advantageously participated to improve biological activities of CUR. We have attempted to summarize these delivery approaches, and reviewed future trends/strategies to permit the introduction of CUR as practical therapeutic drug. [ABSTRACT FROM AUTHOR]

Human biosynthetic insulin is a polypeptide hormone that plays an important and essential role in control of the level of carbohydrate, protein, and fat metabolism in the blood. Human pancreatic insulin was labeled with Tc to form a new radiopharmaceutical with a labeling yield of 99 ± 1% under optimum conditions: 0.1 mL insulin, pH 7, 25 μg stannous chloride, 1 mL (19 mCi) of pertechnetate, room temperature, and 10 min reaction time. The Tc-insulin complex was examined using paper chromatography, ITLC, electrophoresis, and HPLC. In addition, in vitro and in vivo study of Tc-insulin complex was performed at different time intervals. [ABSTRACT FROM AUTHOR]

Environmentally friendly waterborne polyurethane (WPU) coatings are used extensively due to their low VOCs emission than solvent based PU coatings. Additionally, WPU coatings have low temperature flexibility, pH stability, water resistance, superior solvent resistance, outstanding weathering resistance and desirable chemical and mechanical properties. This review provides an overview on the recent developments of WPU coatings and their value added applications in the coatings and paint industry. UV-cured WPU coatings provide an important class of green and ecofriendly coatings with outstanding mechanical properties and rapid curing system. Hyper-branched polyurethanes (PUs) show interesting properties, such as high solubility, reactivity and good rheological behavior owing to multiple end groups, compact molecular structure and diminishing chain entanglement. Inherently, WPU coatings have reduced stiffness and mechanical strength that can be increased by the addition of nanoparticles, like Ag, Cu, TiO, SiO and many more. Fire retardants, commonly phosphorous, are incorporated in the WPU structure to increase the flame retardancy of WPU coatings. [ABSTRACT FROM AUTHOR]

The dispersibility of diamond has been improved by reforming its surface with 2-propanol-2-yl $${[({\rm CH}_{3})_{2}{\rm C}^{{\cdot}}{\rm OH}]}$$ radicals. These radicals were produced by the photochemical breakdown of 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one (HPHMP) under ultraviolet (UV) radiations. The diamond particles were mixed with HPHMP in acetone and were placed under UV rays for the generation of required free radicals which were in situ reformed the diamond surface. Fourier transform infrared, nuclear magnetic resonance spectroscopy and scanning electron microscopy (SEM) confirmed the structural and surface reforming of diamond. The thermogravimetric analysis, thermogravimetric analysis-mass spectrometry spectrogram confirmed the surface reforming of diamond with 2-propanol-2-yl radicals. The dispersion behavior of the diamond after reforming was observed by SEM analysis and revealed an improvement in dispersibility in common solvents. [ABSTRACT FROM AUTHOR]

A series of polyurethane elastomers (PUEs) were prepared by the reaction of hydroxyl-terminated polybutadiene (HTPB) and toluene diisocyanate (TDI), the resultant PU prepolymer was extended with polydimethyl siloxane (PDMS). The conventional spectroscopic characterization of the synthesized samples using Fourier transform infrared spectrophotometer confirmed the structure of the proposed PDMS-based PU. Thermogravimetric analysis (TGA) was carried out to determine the thermal stability of the prepared PU samples. Surface properties of the synthesized material were studied determining the percentage of water absorption and equilibrium degree of swelling. The results revealed that by increasing the mole ratio of PDMS, the synthesized PUEs showed hydrophilic behavior while placing them in water and dimethyl sulfoxide solvent. [ABSTRACT FROM AUTHOR]

The present research work was performed to study the properties of siloxane-based polyurethane (SPU) elastomers using aliphatic diisocyanate. SPU samples constituting of hexamethylene diisocyanate, hydroxyl-terminated polybutadiene, and polydimethylsiloxane (PDMS) were synthesized by two-step polymerization technique. Molecular engineering and surface characterization were carried out, and the outcome of the results was discussed. The conventional spectroscopic characterization of the synthesized samples using Fourier transform infrared spectroscopy confirms the existence of the proposed SPU structure. Surface properties of the synthesized material were studied determining the percentage of water absorption and equilibrium of the degree of swelling. It was found that by increasing the mole ratio of PDMS, the synthesized PU samples showed hydrophobic behavior while placing them in water and in dimethylsulfoxide solvent. [ABSTRACT FROM AUTHOR]

The present research work was performed to study the properties of polyurethanes (PU) based on aliphatic diisocayanate and the effect of chemical structure of chain extenders. Two series of PUs were synthesized via two steps polymerization technique. The PU samples constituted on hexamethylene diisocayanate (HDI), hydroxy-terminated polybutadiene (HTPB) and blends 1, 4 butanediol (BDO)/bisphenol A (BPA) and or 1, 4 butanediol (BDO)/ bisphenol S (BPS) were prepared. Structural characterization was done using Fourier transform infrared spectroscopy during and after the synthesis. The FTIR analysis confirmed the existence of proposed bisphenol A (BPA) and bisphenol S (BPS) based PU structures. Differential scanning calorimeter (DSC) analysis gives information about the thermal transition of all the polymer samples. Because of the difference of polarity between hard and soft segments of PU, microphase separation can occur. The degree of phase separation in the prepared PU was confirmed using scanning electron microscope (SEM) technique. The SEM techniques present a distinctive chance to directly visualize the morphology of the polyurethanes. [ABSTRACT FROM AUTHOR]

Self-assembled hollow microspheres poly( o-chloroaniline) (POC) have been synthesized by simple oxidative polymerization of o-chloroaniline using camphor-sulfonic acid (CSA) as dopant acid and ammonium persulfate (APS) as oxidant. The POC microspheres were characterized by means of FTIR, XRD and SEM analysis. Adsorption characteristics of POC spheres were studied by using methyl orange (MO) as adsorbate. It was found that adsorption of MO by POC was better described by pseudo-second-order kinetics than any other kinetic model, such as the pseudo-first-order and intra-particle diffusion models. Langmuir adsorption isotherm model was the best to fit experimental data. The results showed that hollow microspheres of POC can be used as novel and low-cost adsorbent for removal of organic dye from waste water. [ABSTRACT FROM AUTHOR]

Polyurethanes (PUs) prepolymers blended with bentonite nanoclay and without bentonite nanoclay were prepared by the reaction of toluene-2,4-diisocyanate (TDI) and hydroxyl terminated polybutadiene (HTPB), and the chain was further extended with 1,4-butane diol (1,4-BDO) to get final polyurethane nanocomposites (PUNC). A mixture of polymer and bentonite clay enriched in montmorillonite (MMT) was formed in solution polymerization, in which MMT dispersed depending on interaction of MMT with polymer chains. The molecular structure of the monomers and the prepared PU nanocomposites was confirmed by FTIR. A series of PUNCs were prepared by varying the percent compositions of bentonite nanoclay into the PU matrix. The existence of the clay in to the PU was confirmed by scanning electron microscope (SEM). SEM images verified the good dispersion of the bentonite nanoclay in PU matrix. [ABSTRACT FROM AUTHOR]

The effect of structural chemistry of different soft segments on various structural properties of polyurethane-urea (PUU) elastomers was evaluated in this study. A series of PUU elastomers were prepared by the reaction of 4,4'-diisocyanato dicylohexylmethane (H12MDI) with polycaprolactone (PCL), Polytetramethylene glycol (PTMG), Polyethylene glycol (PEG), Polybutylene adipate (PBA) and amine chain extender 4,4'-methylenebis(2,6-diethylaniline) (MBDEA). Fourier transform infrared (FTIR) spectroscopy was used to study the synthesis of final PUU elastomers. Thermal behaviour of PUU elastomers was investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. The surface properties and hardness of elastomers were characterized by measuring contact angle and hardness in shore A scale. The results showed highest thermal stability and hydrophobicity of PUPCL i.e., Polycaprolactone polyol based PUU elastomer. The proposed synthesis of PUU elastomers was confirmed by the appearance of -NH peak at 3305-3315 cm-1 and disappearance of -NCO peak at 2270 cm-1 in FTIR spectra. [ABSTRACT FROM AUTHOR]

ABSTRACT We prepared and then blended polyurethanes (PUs) with poly(methyl methacrylate)s (PMMAs) and TiO2 by varying the percentage compositions to form pellets. The chemistry of all of the blended samples was confirmed by Fourier transform infrared spectroscopy. The incorporation of TiO2 into the PU-PMMA matrix was confirmed with scanning electron microscopy analysis. Differential scanning calorimetry analysis and compression testing was performed, and the results are discussed. The cytotoxicity level of the prepared blends displayed dependence on the composition ratio of the PU-PMMA blends. The results reveal that the optimum PU contents in the PU-PMMA-TiO2 blend were responsible for its better biocompatibility. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39806. [ABSTRACT FROM AUTHOR]

Aqueous polyurethane dispersions (PUDs) have recently emerged as important alternatives to their solvent-based counterparts for various applications due to increasing health and environmental awareness. A series of aqueous polyurethane dispersions containing carboxylate anion as hydrophilic pendant groups were synthesized through step growth polymerization reaction using hexamethylene diisocyanate (HDI), 1,4-butanediol (1,4-BDO), dimethylol propionic acid (DMPA) and polyethylene glycol (PEG) of different molecular weight. Effect of PEG molecular weight was investigated on molecular structure, contact angle measurement, and physical and adhesive properties of PU emulsions. Fourier transform infrared spectroscopy (FT-IR) was used to check the completion of polymerization reaction. Contact angle measurement indicated that the hydrophilicity of polymer increases by increasing molecular weight of PEG with a corresponding decrease in contact angle. Results of T-peel test showed a decrease in peel strength by increasing molecular weight of PEG. Moreover, solid contents%, drying time and storage stability suggested fast drying properties and greater stability of aqueous PU dispersions. [ABSTRACT FROM AUTHOR]

A requirement for optimum performance in a pressure-sensitive adhesive (PSA) is the right balance between viscous and elastic properties, achieved by controlling the molecular architecture. Here, waterborne polyurethane PSAs are synthesized using a blend of polyether and polyalkene-based polyols. The effects of the polyol type and molecular weight on the adhesive and thermomechanical properties are explored to optimize them for PSA applications. A linear polyurethane is synthesized by the reaction of an aliphatic diisocyanate with a diol blend of polypropylene glycol (PPG) and hydroxyl-terminated polybutadiene (HTPB). With increasing concentrations of flexible HTPB segments and the associated increased viscous dissipation a favorable increase in the tack adhesion energy and peel strength is obtained. Adhesive properties are improved with increasing PPG molecular weight because chain entanglements become possible in the soft segments and raise the storage modulus. [ABSTRACT FROM AUTHOR]