Statistical Analysis of Polymer Nanocomposites for Mechanical Properties.

Epoxy resins, due to their high stiffness, ease of processing, good heat, and chemical resistance obtained from cross-linked structures, have found applications in electronics, adhesives coatings, industrial tooling, and aeronautic and automotive industries. These resins are inherently brittle, which has limited their further application. The emphasis of this study is to improve the properties of the epoxy resin with a low-concentration (up to 0.4% by weight) addition of Multi-Walled Carbon Nanotubes (MWCNTs). Mechanical characterization of the modified composites was conducted to study the effect of MWCNTs infusion in the epoxy resin. Nanocomposites samples showed significantly higher tensile strength and fracture toughness compared to pure epoxy samples. The morphological studies of the modified composites were studied using Scanning Electron Microscopy (SEM).

A prospective observational study to evaluate the effect of social and personality factors on continuous positive airway pressure (CPAP) compliance in obstructive sleep apnoea syndrome.

BACKGROUND: Compliance with CPAP treatment for OSAS is not reliably predicted by the severity of symptoms or physiological variables. We examined a range of factors which could be measured before CPAP initiation to look for predictors of compliance. METHODS: This was a prospective cohort-study of CPAP treatment for OSAS, recording; socio-economic status, education, type D personality and clinician's prediction of compliance. RESULTS: We recruited 265 subjects, of whom 221 were still using CPAP at 6 months; median age 53 years, M: F, 3.4:1, ESS 15 and pre-treatment ODI 21/h. Median compliance at 6 months was 5.6 (3.4- 7.1) hours/night with 73.3% of subjects using CPAP ≥4 h/night. No association was found between compliance and different socio-economic classes for people in work, type D personality, education level, sex, age, baseline ESS or ODI. The clinician's initial impression could separate groups of good and poor compliers but had little predictive value for individual patients. Compared to subjects who were working, those who were long term unemployed had a lower CPAP usage and were more likely to use CPAP < 4 h a night (OR 4.6; p value 0.011). A high Beck Depression Index and self-reported anxiety also predicted poor compliance. CONCLUSIONS: In our practice there is no significant association between CPAP compliance with socio-economic status, education or personality type. Long term unemployed or depressed individuals may need more intensive support to gain the optimal benefit from CPAP.

68 Ga-Ca-phytate particles: A potential lung perfusion agent of synthetic origin prepared in a cold kit format.

The objective of this study was to investigate the radiosynthesis of 68 Ga-Ca-phytate particles and then characterize the formulation for radiochemical purity, radioactive particle size distribution, and biodistribution in normal rats. This radiotracer was prepared using a commercial phytate cold kit after reconstitution with saline, 68 Ga-chloride generator eluent, calcium chloride, and air, then heating at 100°C for 30 minutes to achieve 99% radiochemical purity of 68 Ga-particles that were 21% 3-5 µm, 8% 5-15 µm, and 71% >15 µm in diameter. This optimal formulation was stable for 2 hours at room temperature. Intravenous administration of 68 Ga-particles in rats resulted in an uptake of 93% in the lungs, 4% in the liver plus spleen, and 3% in the carcass after 20 minutes. Two-thirds of the carcass activity was radioactive blood, likely to be 68 Ga-transferrin. The positron emission tomography image was superior than the 99m Tc-MAA image because it displayed high lung uptake against a low background. Low uptake by the liver, spleen did not interfere with the diagnostic quality, and faint activity in the submandibular (salivary) glands was due to 68 Ga-transferrin. The preclinical data so far indicate that 68 Ga-Ca-phytate particles have good potential as a lung perfusion imaging agent.

An improved assay for (68)Ga-hydroxide in (68)Ga-DOTATATE formulations intended for neuroendocrine tumour imaging.

The objective of this study was to identify a more rapid assay for (68)Ga(OH)3 impurity in (68)Ga-DOTATATE formulations. Three methods were used to prepare (68)Ga(OH)3 reference material (pharmacopoeial, bench titration and automated radiosynthesis), and four quality control methods for its assessment (thin layer chromatography, membrane filtration, HPLC and solid phase extraction). The optimal method of preparing (68)Ga(OH)3 was by titrating (68)Ga(3+) with buffered sodium hydroxide solutions to pH 5.6 ± 0.2. The precipitate was quantitatively isolated by membrane filtration (0.02 µm)/hydrochloric acid (HCl; pH 5.6) solvent, and also it remained 100% at the origin on instant thin layer chromatography with silica gel paper/HCl (pH 5.6) solvent. For (68)Ga-DOTATATE samples, the thin layer chromatography technique was used with a single paper strip developed separately on two occasions, once in HCl (pH 5.6) and next in methanol solvent. This so-called double-developed (DD) method separated (68)Ga(OH)3 impurity located at the origin, from (68)Ga-DOTATATE plus (68)Ga(3+) at ~Rf 0.4, and it was superior to the other methods. It assayed for the impurity similarly to the pharmacopoeial method. The advantages of the DD method were that it required inexpensive test materials and it reproducibly determined % (68)Ga(OH)3 in (68)Ga-DOTATATE in 12 min, 13 min earlier than the pharmacopoeial method. This time efficiency resulted in a surplus of 12% (68)Ga-DOTATATE counts in the product vial, and this provided a contingency of radioactivity or time for the injection/imaging processes in the Nuclear Medicine Department.

Pre-flight assessment in patients with obesity hypoventilation syndrome.

BACKGROUND AND OBJECTIVE: Reduced atmospheric pressure during air travel can cause significant hypoxaemia in some patients with respiratory disease. Our aims were to investigate the degree of hypoxaemia in patients with obesity hypoventilation syndrome (OHS) during hypoxic challenge test (HCT), and to identify any predictors of a positive HCT. METHODS: Thirteen patients underwent assessment, including HCT, lung function and incremental shuttle walk test. All had OHS well controlled with long-term nocturnal non-invasive ventilation (NIV). Patients with chronic obstructive pulmonary disease were excluded. A positive HCT was defined according to the British Thoracic Society (BTS) recommendation as arterial oxygen tension (PaO2) <6.6 kPa and/or oxygen saturation <85%. RESULTS: Mean age was 57 (± 11) years. Mean body mass index was 51.7 (± 12) kg/m(2) . Mean baseline PaO2 and arterial carbon dioxide tension (PaCO2) were 10.2 (9.5-11.3) kPa and 5.2 (3.7-6.8) kPa, respectively. Seven patients (54%) had a positive HCT. The correlation between baseline PaO2 and PaO2 at the end of the HCT was not statistically significant (r = 0.433, P = 0.184). A negative correlation was observed between baseline PaCO2 and PaO2 at the end of the HCT (r = -0.793, P = 0.004). A positive correlation was observed between the distance walked and the PaO2 at the end of the HCT (r = 0.608, P = 0.047). CONCLUSIONS: OHS is a risk factor for severe hypoxaemia during air travel even if the ventilatory failure is well controlled. An HCT before air travel is advisable in all OHS patients. Those with positive HCT may use NIV or have oxygen on-board as per BTS recommendation.

Modeling of Interfacial Tension and Inclusion Motion Behavior in Steelmaking Continuous Casting Mold.

The current work is an expansion of our previous numerical model in which we investigated the motion behavior of mold inclusions in the presence of interfacial tension effects. In this paper, we used computational fluid dynamic simulations to examine the influence of interfacial tension on inclusion motion behavior near to the solid-liquid interface (solidifying shell). We have used a multiphase model in which molten steel (SPFH590), sulfur, and alumina inclusions have been considered as different phases. In addition, we assume minimal to negligible velocity at the solid-liquid interface, and we restrict the numerical simulation to only include critical phenomena like heat transport and interfacial tension distribution in two-dimensional space. The two-phase simulation of molten steel mixed with sulfur and alumina was modeled on volume of fluid (VOF) method. Furthermore, the concentration of the surfactant (sulfur) in molten steel was defined using a species model. The surfactant concentration and temperature affect the Marangoni forces, and subsequently affects the interfacial tension applied on inclusion particles. It was found that the alteration in interfacial tension causes the inclusion particles to be pushed and swallowed near the solidifying boundaries. In addition, we have compared the computational results of interfacial tension, and it was found to be in good agreement with experimental correlations.

Reduction in environmental CO2 by utilization of optimized energy scheme for power and fresh water generations based on different uses of biomass energy.

Renewable energy sources are undoubtedly necessary, considering global electricity demand is expected to rise dramatically in the coming years. This research looks at a unique multi-generation plant from the perspectives of exergy, energy, and economics; also, an environmental evaluation is performed to estimate the systems' CO2 emissions. The unit is made up of a biomass digester and gasifier, a Multi effect Desalination unit, and a supercritical CO2 (SCO2) cycle. In this study, two methods for using biomass are considered: the first is using synthesis gas generated by the gasifier, and the second is utilizing a digester to generate biogas. A comprehensive parametric study is performed on the designed energy unit to assess the influence of compressor pressure ratio, Gas turbine inlet temperature, supercritical CO2 cycle pressure ratio, and the number of effects of multi-effect distillation on the system performance. Furthermore, the exergy study revealed that the exergy destruction in the digestion unit was 11,337 kW, which was greater than the exergy destruction in the gasification unit, which was 9629. Finally, when compared to the gasifier, the amount of exergy efficiency, net output power, and freshwater production in the digester was greater.

Using a Topical Formulation of Vitamin D for the Treatment of Vitiligo: A Systematic Review.

Vitamin D is one significant prohormone substance in human organ systems. It is a steroidal hormone produced in the skin upon exposure to UVB rays. This paper presents a systematic review of the utilization of topical vitamin D, specifically cholecalciferol, calcipotriol, and tacalcitol, in the treatment of vitiligo. It considers the role of vitamin D in stimulating the synthesis of melanin and melanogenesis, which can help with the process of repigmentation. The inclusion of calcipotriol or tacalcitol in Narrowband Ultraviolet Phototherapy (NB-UVB) has shown the potential to enhance therapeutic outcomes for vitiligo. However, their effectiveness in combination with Psoralens Long Wave Ultraviolet Radiation (PUVA) and Monochromatic Excimer Light (MEL) treatment for vitiligo is limited. In contrast, combining topical corticosteroids with vitamin D analogues has demonstrated superior efficacy in treating vitiligo compared to using vitamin D analogues alone, while also providing the added benefit of reducing corticosteroid-related adverse effects. In addition, treating stable vitiligo with topical cholecalciferol and microneedling has shown success. Future studies are needed to ascertain an efficient method of administering vitamin D topically as an anti-vitiligo agent.

Mathematical modeling of active contraction of the human cardiac myocyte: A review.

Background and objective: In this present research paper, a mathematical model has been developed to study myocyte contraction in the human cardiac muscle, using the Land model. Different parts of the human heart with a focus on the composition of the myocyte cells have been explored numerically to enabling us to determine the interaction of various parameters in the heart muscle. The main objective of the work is to direct the study of the Land model, which has been exploited to simulate the contraction of real human myocytes. Methods: Mathematical models has been developed based on the Hill model and Huxley model. Myocyte contraction for different scenarios, such as in isometric tension and isotonic tension have been studied. Results: It is found that increase in stretch, the peak active tension increases, in line with well-established length-dependent tension generation. Five parameters are selected: [Ca2+]T50, Tref, TRPN50, ß0, and ß1, which have been varied in between the range of -50%-100%, to examine the isometric effects of each parameter on the behavior of the tension developed in the intact myocyte cells, with the most sensitive parameter being [Ca2+]T50. Conclusion: In conclusion, it is found that the Land model provides a good platform for the analysis of the active contraction of the human cardiac myocyte.

Osteoimmune-modulating and BMP-2-eluting anodised 3D printed titanium for accelerated bone regeneration.

3D printing of titanium (Ti) metal has potential to transform the field of personalised orthopaedics and dental implants. However, the impacts of controlled surface topographical features of 3D printed Ti implants on their interactions with the cellular microenvironment and incorporation of biological growth factors, which are critical in guiding the integration of implants with bone, are not well studied. In the present study, we explore the role of surface topological features of 3D printed Ti implants using an anodised titania nanotube (TiNT) surface layer in guiding their immune cell interaction and ability to deliver bioactive form of growth factors. TiNT layers with precisely controlled pore diameter (between 21and 130 nm) were anodically grown on 3D printed Ti surfaces to impart a nano-micro rough topology. Immune biomarker profiles at gene and protein levels show that anodised 3D Ti surfaces with smaller pores resulted in classical activation of macrophages (M1-like), while larger pores (i.e., >100 nm) promoted alternate activation of macrophages (M2-like). The in vitro bone mineralisation studies using the conditioned media from the immunomodulatory studies elucidate a clear impact of pore diameter on bone mineralisation. The tubular structure of TiNTs was utilised as a container to incorporate recombinant human bone morphogenetic protein-2 (BMP-2) in the presence of various sugar and polymeric cryoprotectants. Sucrose offered the most sustainable release of preserved BMP-2 from TiNTs. Downstream effects of released BMP-2 on macrophages as well as bone mineralisation were assessed showing bioactivity retention of the released rhBMP-2. Overall, the TiNT surface topography in combination with controlled, sustained, and local release of bioactive growth factors can potentially enhance the osseointegration outcomes of custom 3D printed Ti implants in the clinic.

Dissolvable polymer microneedles for drug delivery and diagnostics.

Dissolvable transdermal microneedles (µND) are promising micro-devices used to transport a wide selection of active compounds into the skin. To provide an effective therapeutic outcome, µNDs must pierce the human stratum corneum (~10 to 20 µm), without rupturing or bending during penetration, then release their cargo at the predetermined area and time. The ability of dissolvable µND arrays/patches to sufficiently pierce the skin is a crucial requirement, which depends on the material composition, µND geometry and fabrication techniques. This comprehensive review not only provides contemporary knowledge on the µND design approaches, but also the materials science facilitating these delivery systems and the opportunities these advanced materials can provide to enhance clinical outcomes.

The Effect of Roughness in Absorbing Materials on Solar Air Heater Performance.

Artificial roughness on the absorber of the solar air heater (SAH) is considered to be the best passive technology for performance improvement. The roughened SAHs perform better in comparison to conventional SAHs under the same operational conditions, with some penalty of higher pumping power requirements. Thermo-hydraulic performance, based on effective efficiency, is much more appropriate to design roughened SAH, as it considers both the requirement of pumping power and useful heat gain. The shape, size, and arrangement of artificial roughness are the most important factors for the performance optimization of SAHs. The parameters of artificial roughness and operating parameters, such as the Reynolds number (Re), temperature rise parameter (ΔT/I) and insolation (I) show a combined effect on the performance of SAH. In this case study, various performance parameters of SAH have been evaluated to show the effect of distinct artificial roughness, investigated previously. Therefore, thermal efficiency, thermal efficiency improvement factor (TEIF) and the effective efficiency of various roughened absorbers of SAH have been predicted. As a result, thermal and effective efficiencies strongly depend on the roughness parameter, Re and ΔT/I. Staggered, broken arc hybrid-rib roughness shows a higher value of TEIF, thermal and effective efficiencies consistently among all other distinct roughness geometries for the ascending values of ΔT/I. This roughness shows the maximum value of effective efficiency equals 74.63% at a ΔT/I = 0.01 K·m2/W. The unique combination of parameters p/e = 10, e/Dh = 0.043 and α = 60° are observed for best performance at a ΔT/I higher than 0.00789 K·m2/W.

Performance of Microchannel Heat Sink Made of Silicon Material with the Two-Sided Wedge.

New designs of the microchannel with a two-sided wedge shape at the base were studied numerically. Five different wedge angles ranging from 3° to 15° were incorporated into the microchannel design. Simulation of this novel microchannel was carried out using Computational Fluid Dynamics (CFD). Three-dimensional models of the microchannel heat sink were created, discretized, and based on Navier-Stokes and energy equations; laminar numerical solutions were obtained for heat transfer and pressure drop. Flow characteristics of water as coolant in a microchannel were studied. It was observed that numerical results are in good agreement with experimental results. It was found that the Nusselt number and friction factor are significantly varied with the increase in Reynolds number. The Nusselt number varies in the following ranges of 5.963-8.521, 5.986-8.550, 6.009-8.568, 6.040-8.609, and 6.078-8.644 at 3°, 6°, 9°, 12°, and 15°, respectively. The microchannel with a wedge angle of 15° was found to be better in terms of Nusselt number and thermo-hydraulic performance. The enhancement in the Nusselt number is found as 1.017-1.036 for a wedge angle of 15°; however, friction factors do not show the perceptible values at distinct values of wedge angle. Moreover, the thermo-hydraulic performance parameters (THPP) were evaluated and found to be maximum in the range of 1.027-1.045 for a wedge angle of 15°. However, minimum THPP was found in the range of 1.005-1.0185 for a wedge angle of 3°.

Analysis of Microchannel Heat Sink of Silicon Material with Right Triangular Groove on Sidewall of Passage.

Microchannel heat sink (MCHS) is a promising solution for removing the excess heat from an electronic component such as a microprocessor, electronic chip, etc. In order to increase the heat removal rate, the design of MCHS plays a vital role, and can avoid damaging heat-sensitive components. Therefore, the passage of the MCHS has been designed with a periodic right triangular groove in the flow passage. The motivation for this form of groove shape is taken from heat transfer enhancement techniques used in solar air heaters. In this paper, a numerical study of this new design of microchannel passage is presented. The microchannel design has five variable groove angles, ranging from 15° to 75°. Computational fluid dynamics (CFD) is used to simulate this unique microchannel. Based on the Navier-Stokes and energy equations, a 3D model of the microchannel heat sink was built, discretized, and laminar numerical solutions for heat transfer, pressure drop, and thermohydraulic performance were derived. It was found that Nusselt number and thermo-hydraulic performance are superior in the microchannel with a 15° groove angle. In addition, thermohydraulic performance parameters (THPP) were evaluated and discussed. THPP values were found to be more than unity for a designed microchannel that had all angles except 75°, which confirm that the proposed design of the microchannel is a viable solution for thermal management.

Advances and future perspectives in epithelial drug delivery.

Epithelial surfaces protect exposed tissues in the body against intrusion of foreign materials, including xenobiotics, pollen and microbiota. The relative permeability of the various epithelia reflects their extent of exposure to the external environment and is in the ranking: intestinal≈ nasal ≥ bronchial ≥ tracheal > vaginal ≥ rectal > blood-perilymph barrier (otic), corneal > buccal > skin. Each epithelium also varies in their morphology, biochemistry, physiology, immunology and external fluid in line with their function. Each epithelium is also used as drug delivery sites to treat local conditions and, in some cases, for systemic delivery. The associated delivery systems have had to evolve to enable the delivery of larger drugs and biologicals, such as peptides, proteins, antibodies and biologicals and now include a range of physical, chemical, electrical, light, sound and other enhancement technologies. In addition, the quality-by-design approach to product regulation and the growth of generic products have also fostered advancement in epithelial drug delivery systems.

A Numerical Investigation on Hydrothermal Performance of Micro Channel Heat Sink with Periodic Spatial Modification on Sidewalls.

Electronic gadgets have been designed to incorporating very small components such as microcontrollers, electronic chips, transistors, microprocessors, etc. These components are exceptionally heat sensitive and can be wrecked if heat is not released. As a result, the thermal control of such components is critical to their optimum performance and extended life. The use of a microchannel heat sink (MCHS) has shown promising solutions to remove the excess heat. In this paper, we have proposed a novel design of MCHS and investigated it numerically. Four different surface modifications on the sidewall of the passage, namely, extended triangular surface (ETS), extended circular surface (ECS), triangular groove surface (TGS), and the circular groove surface (CGS) in the passage of the microchannel have been exploited in the Reynolds number of 100-900. In the presence of geometrical modification, the cooling capacities have been enhanced. The results show that the Nusselt numbers of ETS-MCHS, ECS-MCHS, TGS-MCHS, and CGS-MCHS are increased by 4.30, 3.61, 1.62, and 1.41 times in comparison to the Nusselt number of MCHS with smooth passage, while the friction factor values are increased by 7.33, 6.03, 2.74, and 1.68 times, respectively. In addition, the thermohydraulic performance parameter (THPP) has been evaluated and discussed. The fact that MCHS have THPP values greater than unity demonstrates that the passage's geometries are a practical means of achieving effective thermal management.

Modeling of Melt Flow and Heat Transfer in Stationary Gas Tungsten Arc Welding with Vertical and Tilted Torches.

A 3D numerical simulation was conducted to study the transient development of temperature distribution in stationary gas tungsten arc welding with filler wire. Heat transfer to the filler wire and the workpiece was investigated with vertical (90°) and titled (70°) torches. Heat flux, current flux, and gas drag force were calculated from the steady-state simulation of the arc. The temperature in the filler wire was determined at three different time intervals: 0.12 s, 0.24 s, and 0.36 s. The filler wire was assumed not to deform during this short time, and was therefore simulated as solid. The temperature in the workpiece was calculated at the same intervals using heat flux, current flux, gas drag force, Marangoni convection, and buoyancy. It should be noted that heat transfer to the filler wire was faster with the titled torch compared to the vertical torch. Heat flux to the workpiece was asymmetrical with both the vertical and tilted torches when the filler wire was fully inserted into the arc. It was found that the overall trends of temperature contours for both the arc and the workpiece were in good agreement. It was also observed that more heat was transferred to the filler wire with the 70° torch compared with the 90° torch. The melted volume of the filler wire (volume above 1750 °K) was 12 mm3 with the 70° torch, compared to 9.2 mm3 with the 90° torch.

Leverage of Environmental Pollutant Crump Rubber on the Dry Sliding Wear Response of Epoxy Composites.

The effect of crump rubber on the dry sliding wear behavior of epoxy composites is investigated in the present study. Wear tests are carried out for three levels of crump rubber (10, 20, and 30 vol.%), normal applied load (30, 40, and 50 N), and sliding distance (1, 3, and 5 km). The wear behavior of crump rubber-epoxy composites is investigated against EN31 steel discs. The hybrid mathematical approach of Taguchi-coupled Grey Relational Analysis (GRA)-Principal Component Analysis (PCA) is used to examine the influence of crump rubber on the tribological response of composites. Mathematical and experimental results reveal that increasing crump rubber content reduces the wear rate of composites. Composites also show a significant decrease in specific wear values at higher applied loads. Furthermore, the coefficient of friction also shows a decreasing trend with an increase in crump rubber content, indicating the effectiveness of reinforcing crump rubber in a widely used epoxy matrix. Analysis of Variance (ANOVA) results also reveal that the crump rubber content in the composite is a significant parameter to influence the wear characteristic. The post-test temperature of discs increases with an increase in the applied load, while decreasing with an increase in filler loading. Worn surfaces are analyzed using scanning electron microscopy to understand structure-property correlations. Finally, existing studies available in the literature are compared with the wear data of the present study in the form of a property map.

A randomised crossover trial comparing volume assured and pressure preset noninvasive ventilation in stable hypercapnic COPD.

Recent randomised controlled trials suggest non-invasive ventilation may offer benefit in the long-term management of ventilatory failure in stable COPD. The best mode of ventilation is unknown and newer volume assured modes may offer advantages by optimising ventilation overnight when treatment is delivered. This study compares volume assured with pressure preset non-invasive ventilation. Randomised crossover trial including twenty five subjects previously established on long-term non-invasive ventilation to manage COPD with chronic ventilatory failure. Two 8-week treatment periods of volume assured and pressure preset non-invasive ventilation. The primary outcomes were daytime arterial blood gas tensions and mean nocturnal oxygen saturation. Secondary outcomes included lung function, exercise capacity, mean nocturnal transcutaneous carbon dioxide, health status and compliance. No significant differences were seen in primary or secondary outcomes following 8 weeks of treatment when comparing volume assured and pressure preset ventilation. Primary outcomes assessed: mean (standard deviation) PaO(2) 7.8 (1.2) vs 8.1(1) kPa, PaCO(2) 6.7 (1.1) vs 6.3 (1.2) kPa and mean nocturnal oxygenation 90 (4) vs 91 (3)% volume assured versus pressure preset, respectively. Volume assured and pressure preset non-invasive ventilation appear equally effective in the long-term management of ventilatory failure associated with stable COPD.

3D QSAR pharmacophore-based virtual screening for the identification of potential inhibitors of tyrosinase.

Tyrosinase plays an important role in melanin biosynthesis and protects skin against ultraviolet radiations. Functional deficiency of tyrosinase results in serious dermatological diseases. Tyrosinase also participates in neuromelanin formation in the human brain, which leads to neurodegeneration resulting in Parkinson's disease. In fruits and vegetables, tyrosinase plays a critical role in senescence, causing undesired browning that results in faster deterioration and shorter shelf lines. The only commercially available tyrosinase is mushroom tyrosinase and it shows the highest homology to the mammalian tyrosinase. Although kojic acid is currently used as a tyrosinase inhibitor, they have serious side effects such as dermatitis, carcinogenesis and hepatotoxicity. Therefore, in order to develop a more active and safer tyrosinase inhibitor, 3D QSAR pharmacophore models were generated based on experimentally known inhibitors. The pharmacophore model, Hypo1, was developed with a large cost difference, high correlation coefficient and low RMS deviation. Hypo1 showed a good spatial arrangement; consisting of five-point features including two hydrogen bond acceptor, one hydrogen bond donor and two hydrophobic features. Hypo1 was further validated by cost analysis, test set and Fisher's randomisation method. Hypo1 was used as a 3D query for screening the in-house drug-like databases, and the hits were further selected by applying ADMET, Lipinski's rule of five and fit value criteria. To identify binding conformations, the obtained hits were subjected to molecular docking. Finally, molecular dynamics simulations revealed the appropriate binding modes of hit compounds. To conclude, we propose the final three hit compounds with new structural scaffolds as a virtual candidate as tyrosinase inhibitors.Communicated by Ramaswamy H. Sarma.