Microfluidic preparation of polymer nanospheres

In this work, solid polymer nanospheres with their surface tailored for drug adhesion were prepared using a V-shaped microfluidic junction. The biocompatible polymer solutions were infused using two channels of the microfluidic junction which was also simultaneously fed with a volatile liquid, perfluorohexane using the other channel. The mechanism by which the nanospheres are generated is explained using high speed camera imaging. The polymer concentration (5-50 wt%) and flow rates of the feeds (50-300 µl min(-1)) were important parameters in controlling the nanosphere diameter. The diameter of the polymer nanospheres was found to be in the range of 80-920 nm with a polydispersity index of 11-19 %. The interior structure and surfaces of the nanospheres prepared were studied using advanced microscopy and showed the presence of fine pores and cracks on surface which can be used as drug entrapment locations

Polyphenol-rich fruits attenuate impaired endothelial function induced by glucose and free fatty acids in vitro in human endothelial cells

Elevated concentrations of plasma glucose and free fatty acids (FFA) are associated with impaired endothelial function increasing risk of cardiovascular diseases. Previous studies suggested that fruits rich in polyphenolic compounds modulate endothelial cell migration and capillary-like tube formation via a redox-sensitive mechanism. We hypothesized that polyphenol-rich extracts of strawberry (SB) and wild blueberry (WB) would attenuate relatively high concentrations of glucose and/or FFA–mediated impaired cell migration and capillary-like tube formation in vitro in human umbilical vein endothelial cells (HUVECs). HUVECs treated with high FFA and combinations of glucose and FFA showed significantly reduced cell migration and capillary-like tube formation compared to the PBS control (p<0.05). However, HUVEC pre-treated with SB or WB extracts significantly increased cell migration and capillary-like tube formation in cells treated with FFA or a combination of FFA and glucose compared to cells exposed to the same nutrients/combinations alone. The results from this study suggest that berry fruits may play a role in promoting cardiovascular health especially in individuals with high blood glucose and/or FFA levels

Automated Bakery Management System

Providing an automated system to manage the workload of ‘Puzzle’ is the objective of this research. ‘Puzzle’ is a bakery in Sri Lanka. They have been using a handwritten manual system from the origin of the company. They have been able to manage the crowd in the beginning, but with the growing customer crowd, they are having trouble handling their day-to-day workload. Since it is easy, efficient, and effective to have an automated system, they desperately wanted one for their shop. They also mentioned that they do not need a complex system at the beginning since they were used to making use of a manual system, and they wanted to take things slow. After getting used to the new, automated system, they might ask us to add new, complex functionalities such as attendance marking, salary calculation, and leave management. ‘Puzzle’ asked us to add three user types: admin, employee, and customer. Using the respective functionalities for each role will be beneficial for the shop and its users

Utilization of microfluidic V-junction device to prepare surface itraconazole adsorbed nanospheres.

Itraconazole is widely used as an anti-fungal drug to treat infections. However its poor aqueous solubility results in low bioavailability. The aim of the present study was to improve the drug release profile by preparing surface itraconazole adsorbed polymethylsilsesquioxane (PMSQ) nanospheres using a V-junction microfluidic (VJM) device. In order to generate nanospheres with rough surface, the process flow rate of Perfluorohexane (PFH) was set between 50 and 300 μl min(-1) while the flow rate of PMSQ and itraconazole solution were constant at 300 μl min(-1). Variations in the PFH flow rate enable the controlled size generation of nanospheres. PMSQ nanospheres adsorbing itraconazole were characterized by SEM, FTIR and Zetasizer. The release of itraconazole from PMSQ nanosphere surface was measured using UV spectroscopy. Nanosphere formulations with a range of sphere size (120, 320 and 800nm diameter) were generated and drug release was studied. 120nm itraconazole coated PMSQ nanospheres were found to present highest drug encapsulation efficiency and 13% drug loading in a more reproducible manner compared to 320nm and 800nm sized nanosphere formulations. Moreover 120nm itraconazole coated PMSQ nanospheres (encapsulation efficiency: 88%) showed higher encapsulation efficiency compared to 320nm (encapsulation efficiency: 74%) and 800nm (encapsulation efficiency: 62%) sized nanosphere formulations. The itraconazole coated PMSQ nanospheres were prepared continuously at rate of 2.6×10(6) per minute via VJM device. Overall the VJM device enabled the preparation of monodisperse surface itraconazole adsorbed nanospheres with controlled in vitro drug release profile

Impact of Rubber Farming on the Socio-Economic Status of Households of Smallholders: A Descriptive Analysis

Rubber farming in Moneragala District has been introduced to enhance the socio-economic status of households of smallholders. Four focus group discussions and six qualitative case studies were conducted to assess the impact of rubber farming on their household level in 2020. Rubber smallholders were selected for the focus group discussions, using stratified random sampling technique and each discussion was comprised of twelve rubber smallholders. Data was collected using interview criteria which was developed and evaluated prior to its use with the expert team. The rubber smallholders were asked a series of semi-structured questions according to the interview guide by the researcher until theoretical saturation is obtained. Then a set of codes and categories were developed according to the grounded theory approach. Qualitative case studies were carried out with six rubber smallholders who were randomly selected from different land categories. A structured direct interview schedule was used in gathering data from rubber smallholders according to eleven criteria which were developed in collaboration with the expert team. It was highlighted that continuous household income from rubber farming has contributed to meet the expenses of education of children, medicine, food, purchasing agricultural and non-agricultural vehicles and renovation of living house with sustainable household income and regional development in Moneragala. In addition, it has generated new employment opportunities and new source of income for other labourers. Hence, expansion of rubber farming into non-traditional rubber growing areas in the country can be recommended in order to improve the socio-economic status of smallholders.&nbsp;&nbsp;&nbsp;&nbsp; DOI: http://doi.org/10.31357/fhss/vjhss.v08i02.0

Poly(3-hydroxyoctanoate), a promising new material for cardiac tissue engineering

Cardiac tissue engineering (CTE) is currently a prime focus of research due to an enormous clinical need. In this work, a novel functional material, Poly(3-hydroxyoctanoate), P(3HO), a medium chain length polyhydroxyalkanoate (PHA), produced using bacterial fermentation, was studied as a new potential material for CTE. Engineered constructs with improved mechanical properties, crucial for supporting the organ during new tissue regeneration, and enhanced surface topography, to allow efficient cell adhesion and proliferation, were fabricated. Our results showed that the mechanical properties of the final patches were close to that of cardiac muscle. Biocompatibility of the P(3HO) neat patches, assessed using Neonatal ventricular rat myocytes (NVRM), showed that the polymer was as good as collagen in terms of cell viability, proliferation and adhesion. Enhanced cell adhesion and proliferation properties were observed when porous and fibrous structures were incorporated to the patches. Also, no deleterious effect was observed on the adults cardiomyocytes' contraction when cardiomyocytes were seeded on the P(3HO) patches. Hence, P(3HO) based multifunctional cardiac patches are promising constructs for efficient CTE. This work will provide a positive impact on the development of P(3HO) and other PHAs as a novel new family of biodegradable functional materials with huge potential in a range of different biomedical applications, particularly CTE, leading to further interest and exploitation of these materials

Effectiveness of Oil-Layered Albumin Microbubbles Produced Using Microfluidic T-Junctions in Series for In Vitro Inhibition of Tumor Cells

This work focuses on the synthesis of oil-layered microbubbles using two microfluidic T-junctions in series and evaluation of the effectiveness of these microbubbles loaded with doxorubicin and curcumin for cell invasion arrest from 3D spheroid models of triple negative breast cancer (TNBC), MDA-MB-231 cell line. Albumin microbubbles coated in the drug-laden oil layer were synthesized using a new method of connecting two microfluidic T-mixers in series. Double-layered microbubbles thus produced consist of an innermost core of nitrogen gas encapsulated in an aqueous layer of bovine serum albumin (BSA) which in turn, is coated with an outer layer of silicone oil. In order to identify the process conditions leading to the formation of double-layered microbubbles, a regime map was constructed based on capillary numbers for aqueous and oil phases. The microbubble formation regime transitions from double-layered to single layer microbubbles and then to formation of single oil droplets upon gradual change in flow rates of aqueous and oil phases. In vitro dissolution studies of double-layered microbubbles in an air-saturated environment indicated that a complete dissolution of such bubbles produces an oil droplet devoid of a gas bubble. Incorporation of doxorubicin and curcumin was found to produce a synergistic effect, which resulted in higher cell deaths in 2D monolayers of TNBC cells and inhibition of cell proliferation from 3D spheroid models of TNBC cells compared to the control

A Stakeholder Analysis to Assess Preferences and Willingness-to-Pay for Management of Rice Wild Relatives in Sri Lanka

Proper management of rice wild relative populations scattered in Sri Lanka in smallquantities are highly warranted as they constitute an increasingly important genetic resourcethat can be used with further research to increase yield of existing hybrid rice varieties. Inlight of this, this paper presents the outcome of a multi-phased research study carried out toassess the preferences of key stakeholders for conservation and utilisation of thosepopulations. The information contained in databases from a series of empirical analysescarried out with key stakeholders, including the: (a) Breeders (n=30); (b) Environmentmanagers (n=65); (c) Government officials (n=40); (d) Rural communities (n=50), and (e)Urban communities (n=300) were used to select the most relevant attributes pertaining tomanagement of rice wild relatives, including: (1) responsibility for conservation; (2)utilisation of WRR sites; (3) the best conservation method, and (4) Marginal Willingness-to-Pay (MWTP). The outcome of analysis, which employed both Choice Experiment andContingent Ranking methods highlights that the willingness-to-pay of rural adjacentcommunity was significantly higher (Rs. 82.73) than that of urban households (Rs. 1.34),breeders (Rs. 10.00), policy planners (Rs. 20.46) and environmental managers (Rs. 7.34). Theoverall MWTP for all stakeholders was estimated to be Rs. 4.83. It also shows that themajority of stakeholders prefer government takes the sole responsibility of conservation ofWRR and the adjacent communities should be allowed to utilise WRR sites under thesupervision of government. All the stakeholders preferred in-situ conservation. The resultsdraw attention on progressive policy measures which encompass participation of all groups ofstakeholders at equal levels; mainstreaming of conservation activities into livelihooddevelopment strategies to address the local needs, and setting up of alternative institutionalarrangements towards proper execution of policies and research programs aimingconservation of rice wild relatives for the future

Kandyan home gardens: Faunal repositories in Sri Lanka.

Kandyan home gardens are one of the major designs of sustainable land use systems that have evolved over hundreds of years incorporating high biodiversity and providing a diverse and stable supply of socio-economic products and service benefits to householders in Sri Lanka. A study was carried out in three home gardens in the Kandy district from May to December 2009 with the objectives of (a) identifying spatial distribution of terrestrial vertebrates in different vegetation strata, (b) their diurnal and seasonal variations, (c) plant-animal interactions, (d) nesting habits and (e) diet composition. A total of 93 terrestrial vertebrate species including seven amphibians, 23 mammals, 43 birds, and 20 reptiles were recorded. These comprised 14 endemic species, 71 native, four introduced mammals and two migrant birds. Terrestrial vertebrate assemblages were similar in Home garden 1 and 3. According to the fully-nested ANOVA, statistically significant differences were found in the composition of terrestrial vertebrates and the home gardens (P=0.005&lt;0.05), and their vegetation strata (P=0.005&lt;0.05). However, no statistically significant differences were observed between richness of terrestrial vertebrates and the monsoonal periods (P=0.966&gt;0.05), as well as the time of the day (P=0.775&gt;0.05). A positive relationship was obtained between canopy cover and number of bird nests in all home gardens (rs = +1, α = 0.05).Commensalism was the most frequently recorded relationship in all three home gardens. Overall, the diversity of animals and their interactions were different in the three Kandyan Home Gardens studied. Preventing the degradation of home gardens can be considered as a means of conserving biodiversity. There is scope to develop the Kandyan Home Garden system as an important strategy to conserve biodiversity outside the natural and protected area systems

Making nonwoven fibrous poly(epsilon-caprolactone) constructs for antimicrobial and tissue engineering applications by pressurized melt gyration

A pressurized melt gyration process has been used for the first time to generate poly(ε-caprolactone) (PCL) fibers. Gyration speed, working pressure, and melt temperature are varied and these parameters influence the fiber diameter and the temperature enabled changing the surface morphology of the fibers. Two types of nonwoven PCL fiber constructs are prepared. First, Ag-doped PCL is studied for antibacterial activity using Gram-negative Escherichia coli and Pseudomonas aeruginosa microorganisms. The melt temperature used to make these constructs significantly influences antibacterial activity. Neat PCL nonwoven scaffolds are also prepared and their potential for application in muscular tissue engineering is studied with myoblast cells. Results show significant cell attachment, growth, and proliferation of cells on the scaffolds