Using Strontium Coated Clay Nanoparticles For Bone Regeneration And Other Biomedical Applications

The aim of this project is to coat halloysite nanotubes (HNTs) with strontium in an ecofriendly, simple, and non-expensive process. These particles, when doped in calcium phosphate cements (CPC), are predicted to increase the osteoconductive and antibacterial properties of three dimensional (3D) printed bone scaffolds. The purpose of the 3D printed bone scaffolds is to assume the same function as the bones they are replacing but with several additional functionalities. These biomaterials will have the ability to be resorbed as new bone is formed. Due to inherent osteogenic factors and antibiotics released from doped HNTs during the reparative process, it will also provide surgeons with a multi-functional construct for a diverse set of dental and orthopedic applications. The purpose of the 3D printed scaffolds will be to provide a microenvironment for normal cells along with the ability to release antimicrobial, chemotherapeutics or other drugs. The system will also enable growth factor release. Material characterization was conducted to confirm the presence of Sr on the HNTs. Cellular characterizations studies assessed cellular impact and behavior and included cytocompatibility studies, osteogenic/osteoinductive, and differentiation effects on pre-osteoblast cells and stromal cells. Material characterization studies included material strength test of the SrHNT/CPC composites. Based on the results, fabrication methods in future will be modified as needed to obtain the ideal medical construct

Tunable controlled release of molecular species from Halloysite nanotubes

Encouraged by potential applications in rust coatings, self-healing composites, selective delivery of drugs, and catalysis, the transport of molecular species through Halloysite nanotubes (HNTs), specifically the storage and controlled release of these molecules, has attracted strong interest in recent years. HNTs are a naturally occurring biocompatible nanomaterial that are abundantly and readily available. They are alumosilicate based tubular clay nanotubes with an inner lumen of 15 nm and a length of 600-900 nm. The size of the inner lumen of HNTs may be adjusted by etching. The lumen can be loaded with functional agents like antioxidants, anticorrosion agents, flame-retardant agents, drugs, or proteins, allowing for a sustained release of these agents for hours. The release times can be further tuned for days and months by the addition of tube end-stoppers. In this work a three-dimensional, time-quantified Monte Carlo model that efficiently describes diffusion through and from nanotubes is implemented. Controlled delivery from Halloysite Nanotubes (HNT) is modeled based on interactions between the HNT\u27s inner wall and the nanoparticles (NP) and among NPs themselves. The model was validated using experimental data published in the literature. The validated model is then used to study the effect of multiple parameters like HNT diameter and length, particle charge, ambient temperature and the creation of smart caps at the tube ends on the release of encapsulated NPs. The results show that release profiles depend on the size distribution of the HNT batch used for the experiment, as delivery is sensitive to HNT lumen and length. The effect of the addition of end-caps to the HNTs, on the rate of release of encapsulated NPs is also studied here. The results show that the release profiles are significantly affected by the addition of end caps to the HNTs and is sensitive to the end-cap pore lumen. A very good agreement with the experiment is observed when a weight averaged release profile is compared to the experimental profile. Although the NP dynamics is temperature dependent, the effect is minimum within the range of temperatures relevant to biomedical applications, but will be relevant for other applications at temperatures significantly different from room temperature. This model can be used to predict the best conditions for a particular delivery need. One of the possible outcomes of this work is the development of more complex models for HNT–NP interaction various materials used in bioanalytical devices. These models will then be introduced into continuum models of transport in such devices. This work will leverage interaction potential development efforts under the LA-SiGMA grant, to enable multi-scale simulations involving interactions between biomaterials for which such potentials are unknown

Evaluating the microbial safety status of products from sustainable organic agriculture

There has been a steady increase in the demand for organic and sustainable agricultural products. Consumers increasingly prefer non – GMO products grown without pesticides and antibiotics. In order to satisfy the increasing demand, several agricultural producers have opted for use of different types of modern agricultural practices which are more efficient and sustainable than conventional methods. My research focuses on two such modern agricultural practices. Because the products from these methods do not have many food safety interventions applied to them, it is important to make sure that they are free of pathogens and are safe for human consumption. My research 1) Identifies the food safety hazards associated with an aquaponic food production system and studies the efficacy of UV intervention, and 2) Evaluates the food safety status of the initial phase of an integrated crop-livestock organic agricultural system. Aquaponics is a growing trend in food production as it is seen as a sustainable, space- and energy-efficient approach for production of fruits, vegetables and seafood. Within aquaponics, few microbial studies have been conducted to determine the food safety status of its units. The aim of this study was to determine the food safety status and the effectiveness of ultraviolet treatment (15 watt UV light, luminous flux of 900 lumens) as a food safety intervention in reducing the microbial loads of the water system, in a model aquaponic unit that is growing lettuce, basil and barramundi (Australian Sea Bass). Large Leaf basil, Buttercrunch Bibb lettuce, water and fish swab samples were collected throughout the 118-day production period and microbial analysis was conducted for the presence of E. coli O157:H7, Aeromonas and Salmonella spp. and the prevalence of aerobic plate counts (APC), coliforms, and fecal coliforms in the systems in triplicates. Absence of foodborne pathogens was confirmed using ELISA technology (3M™ Tecra, Australia) and enumeration through petrifilms (coliform/E. coli Petrifilm™, 3M, St. Paul, MN) and agar (Aeromonas agar, OXOID, Hants, United Kingdom). A significant increase was observed in aerobic plate counts over the trial period (1 to 3 log CFU/mL), in the presence and absence of UV (p\u3e0.05). Ultraviolet treatment did not significantly reduce the APC, Aeromonas or coliform counts when compared to the control systems samples. Though the UV intervention method was not effective in reducing microbial loads, future work should focus on improving the unit design, evaluation of bio-solid filtration and other food safety interventions that can be effective in the presence of living system while maintaining fish homeostatic environment. Though several researchers have indicated the many benefits associated with the production and consumption of organic food such as restricted use of antibiotics and synthetic chemicals; it must be kept in mind that these benefits do not address the issue of microbial safety. With integrated crop-livestock production systems being relatively new practice in organic agriculture, the aim of this study was to develop and use a model agricultural system to check the food safety status of crops and beef and dairy calves (6-10 months old) produced in an integrated environment in Minnesota (MN), Iowa (IA), and Pennsylvania (PA). Pasture and fecal samples were collected 3 months apart and evaluated for presence of E. coli 0157:H7 and Salmonella using miniVIDAS and confirmation tests were performed according to FDA BAM and USDA standards. Results indicated very low probability for (0.0173-IA, 0.0032-MN, 0.0039-PA) E. coli 0157:H7 and (0.0077-IA, 0.0027-MN, 0.0022-PA) Salmonella occurrence (overall Pr\u3c0.1). The three states were studied individually for occurrence of E. coli 0157:H7 or Salmonella. The probabilities of occurrence were again very low (0.0048-IA, 0.0003-MN, 0.0009-PA). Also, there was no significant difference between the three research sites (p\u3e0.05) in terms of E.coli O157:H7 or Salmonella occurrence. At present, this model has low chance of E.coli O157:H7 and Salmonella being present in the feed and fecal matter, but long term studies including evaluation of meat products and rotational crops might help us better understand the stability of this system

In vitro Antioxidant Activities of Methanol and Aqueous Extract of Annona squamosa (L.) Fruit Pulp

AbstractThe present study evaluated the antioxidant activity of the fruit of Annona squamosa by means of in vitro studies involving two different solvent extracts: methanol and aqueous. The antioxidant properties of the extract were determined by scavenging 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH), lipid peroxidation (LPO), nitric oxide (NO), superoxide anion (O2−), hydroxyl radical (OH•), reducing power and total antioxidant. The results showed that, compared to aqueous extract, a methanolic fruit extract of A squamosa has a higher percentage of inhibition of DPPH radical scavenging activity (97.99%), LPO (94.15%), NO scavenging activity (70.96%), O2− scavenging activity and OH• scavenging activity (78.68% and 85.25%, respectively), total antioxidant activity (206 μg α-tocopherol/g) and reducing power (56.0 μg of ascorbic acid/g). The results obtained in the in vitro models clearly suggest that methanol extract has higher antioxidant activity than the aqueous extract due to a higher presence of phenolic and flavonodal constituents in the methanol extract

Livestock Sector in North-Eastern Region of India: An Appraisal of Performance

Although agriculture is the prime source of livelihood for a majority of rural population in the North-Eastern region (NER) of India, dependence on livestock as an alternative source of income is significant. Responding to the burgeoning demand for livestock products in a sustainable manner is a big challenge. The widening gap between the demand and supply of livestock products can be met through bringing out changes in the production structure or opening up the international trade. In this context, an analysis of performance and factors influencing development of the livestock sector in NER has been carried out. The growth of livestock sector has been found slower in the NER than at the national level. However, a significant proportion of landless labourers, small and marginal farmers have access to livestock resources and acceleration in the growth of livestock in NER offers significant opportunities for household income augmentation and employment generation. Several factors identified to influence households’ decision to rear livestock include availability of labour, occupation, caste, farm-size, availability of irrigation, and access to information sources. The study has shown that the NE states should take technical, institutional and policy initiatives for the improvement of breeds, feed availability, disease control and food safety of livestock.Livestock Production/Industries,

Recovery of nickel from spent NiCd batteries by regular and ultrasonic leaching followed by electrodeposition

This study focuses on the hydrometallurgical route of separating Ni metal from spent nickel cadmium (NiCd) batteries. The comparison of separation of nickel metal with the assistance of ultrasonic leaching and regular leaching was performed. Sulphuric acid (solvent) was used as the lixiviant to leach out the nickel metal ions from the spent battery and the parameters affecting the leaching with and without ultrasonication were optimized. The major parameters affecting the leaching process are volume of solvent, concentration of lixiviant and leaching time. The electrodeposition of nickel metal ions from ultrasonically assisted and regular leaching was carried out at an optimized current density of 8 A dm-2, contact time of 4 hours and the concentration of lixiviant of 5 M. It was observed that the recovery efficiency for ultrasonically assisted leaching followed by electrodeposition is 98.5 %, while in regular leaching followed by electrodeposition is 90.8 %

A Green, Scalable, and Catalyst-Free One-Minute Synthesis of Quinoxalines

A highly efficient and catalyst-free protocol is reported for the synthesis of quinoxalines via the classical cyclocondensation reaction between aryldiamines and dicarbonyl compounds. Remarkably simple and green reaction conditions employing methanol as solvent afforded medium to excellent yield of quinoxalines after only one-minute reaction time at ambient temperature. The conditions allow at least 10 gram scale synthesis of quinoxalines and should be a preferred starting point for optimization and method of choice for applications in the synthetic community

The impact of interpregnancy interval on occurance of preterm births in the present pregnancy

Background: The pregnancy outcomes are influenced by the inter pregnancy intervals. Both short and long inter pregnancy intervals are known to adversely affect the mother and the baby. The main aim of birth spacing was to achieve ideal inter pregnancy intervals and thus to decrease maternal, neonatal morbidity and mortality.Methods: It is a prospective observational study. In this study, about 500 gravida 2 women who has delivered vaginally in the index pregnancy, with gestational age more than 28 weeks of gestation and with known interpregnancy interval were included in the study. They followed up to to delivery and occurance of preterm births in relation to maternal characteristics and interpregnancy interval were analysed.Results: Our study showed that Inter pregnancy intervals of 18-24 months were found to have the least number of preterm births when compared to intervals <18 months and >24 months. This association was found to be statistically significant (p value, Pearson chi square 0.0008). This relationship between inter pregnancy intervals and preterm births persisted when stratified according to maternal age, education, residence and BMI.A previous preterm birth was associated with increased risk of recurrent preterm birth (p value -0.034) and was statistically significant. The history of PROM in present pregnancy associated with preterm birth (p value -0.001) and association was statistically significant.Conclusions: From this study it was found that the 18-24 months birth to pregnancy interval is associated with the least incidence of preterm births.

Lipid Granules Staining (Nile Red and Bodypy) of Different Biofuel Producing Fresh Water Microalgae Growing under Various Stress Conditions

Chlorella vulgaris and Diatoms were cultivated and maintained in different stress system like high light intensity (18:6, Light: Dark) and N2 limited condition.  After the stationary phase, the cells were stained by Nile red and Bodipy.  The slides were examined under fluorescence in situ hybridization microscopy, it showed the Chlorella vulgaris cultivated under N2 limited system yield high lipid bodies than light induced system and Stressed Diatoms.  While Bodipy is a best tool for staining algal lipid bodies than Nile Red stain.ÂÂ

Synthesis of 5,7-diarylindoles via Suzuki-Miyaura coupling in water

The synthesis of novel 5,7-diaryl and diheteroaryl indoles has been explored via efficient double Suzuki–Miyaura coupling. The method notably employs a low catalyst loading of Pd(PPh3)4 (1.5 mol%/coupling) and water as the reaction solvent to obtain 5,7-diarylated indoles without using N-protecting groups in up to 91% yield. The approach is also suitable for N-protected and 3-substituted indoles and constitutes an important green and convenient arylation strategy for the benzenoid ring of indoles. The synthesized diarylindoles are fluorescent