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The present work is focused on the preparation and in vitro release kinetics of liposomal formulation of Leuprolide Acetate. In this work, “Thin Lipid Film Hydration Method” was used for preparation of Leuprolide Acetate loaded liposomes. Prepared liposomal formulations of Leuprolide acetate was evaluated by drug entrapment study, in-vitro drug release kinetics and stability studies. The percentage drug entrapment of Leuprolide acetate for F1 and F2 formulations were found to be 78.14 ± 0.67 and 66.70 ± 0.81% respectively. In-vitro drug release study of liposomal formulations had shown zero order release pattern. Regression co-efficient (R2) value of Zero order kinetics for F1 and F2 formulations were 0.9912 and 0.9676 respectively. After storing formulations for 1 month, stability testing was done at 40C.It was found that all batches were stable. These liposomal formulations of Leuprolide acetate can be formulated for parenteral application to treat prostate cancer and in women, to treat symptoms of endometriosis (overgrowth of uterine lining outside of the uterus) or uterine fibroids.

The aim of this study was to investigate the effect of hydroxypropyl-β-cyclodextrin (HPβCD), widely used as a solubility enhancer, on liposomal formulations. To this end, HPβCD was added to fabricate liposomes during the hydration process, and their physicochemical properties were evaluated. The Fourier transform infrared and nuclear magnetic resonance spectra revealed that HPβCD could interact with the model drug, ceftazidime (CAZ), and with phosphatidylcholine, a main component of liposomes. This leads to a rapid release of CAZ depending on the concentration of HPβCD. Nanosized HPβCD-incorporated liposomes complied with Korsmeyer–Peppas kinetics, and the release of drug increased without significant changes in the release pattern. Our approach, which relied on supramolecule-related interactions, could provide new insights into other lipid-based formulations for accelerating drug-release properties.

Release of silicon (Si) from different Si sources and Si budgeting in varied types of soils are required for the exploration of sustainable rice production. Si products are shown to be effective in...

A laboratory incubation study was conducted during 2018 at College of Agriculture V.C. Farm, Mandya using CRD design with eight treatments and three replication. Treatments included were T1:100% Nitrogen-Urea (NU), T2 to T4: NU: UHA @ 75:25, 50:50 and 25:75 per cent, respectively and T5 to T7: UHA @ 50, 75 and 100%, respectively, T8: Absolute control. Results revealed that application of 100 per cent N through nano UHA increased the content of ammonical-N at 5 DAI (653.3 μg g-1) but the content decreased at 10 DAI (583.3 μg g-1) and increased to 716.7 μg g-1 at 15 DAI and maintained it upto 20 DAI while, it decreased at 45 DAI. The nitrate –N release was highest (596.7 μg g-1) at 10 DAI in T7 treatment and maintained it upto 20 DAI and decreased at 45 DAI. Similar pattern was observed with the application of 75 and 50 per cent N-UHA treatments (T6 and T5, respectively). The amount of release of ammonical and nitrate N was proportional to the amount N added through UHA at any sampling interval.

Aim: To evaluate Enhanced-Biodegradation and Release Pattern of Heavy Metal from Spent Laptop Batteries using Pseudomonas and Bacillus species in Freshwater Study Design: The study employs experimental design, statistical analysis of the data and interpretation. Place and Duration of Study: Freshwater was collected from Isiokpo River, Isiokpo town in Ikwerre L.G.A, Rivers state, Nigeria within co-ordinates 50 02’14’’N and 60 54’50’’E, These samples were transported with ice pack to the Microbiology Laboratory of the Rivers State University, for analyses within 6 hours. Spent laptop batteries were obtained from Ogbunabali Laptops Shoping Complex Garrison area of Port Harcourt, Nigeria. Three sets of the brand of battery (HP, Dell and Acer). Methodology: A total of twelve (12) experimental set-up with three controls (each of the three laptop batteries in freshwater without augmenting organisms) while the other nine were enhanced with augmenting microbes. In step 1, Stock toxicant solution was prepared by soaking the spent Laptop batteries ( of average weight of 300-400g, in two (2) liters of sterilized freshwater in a sterile trough with vented top for aeration, of dimension 12 x 7.5 x 6cm separately for each set-up, The soaking (Toxicant preparation) lasted for 3 months (about 92 days). In step 2, Five hundred milliliters (500ml) of each set-up was transferred into sterile Conical flask plugged with cotton wool perforated for aeration; each was inoculated with five milliliter (5 ml) of the test organisms (Pseudomonas and Bacillus species broth, singly and consortium) separately and monitored for duration 0, 30, 60 and 90 days respectively using the spread plate techniques. The bacterial cultures were incubated at 37°C for 24 hours while fungal cultures were incubated for three (3) days at 35°C. Parameters monitored were Heavy metal (Lithium, Cadmium, Chromium, iron and Lead) concentration, Total Heterotrophic Bacteria, Total Heterotrophic Fungi, Lithium Utilizing Bacteria, Cadmium Utilizing Bacteria, Chromium Utilizing Bacteria, Iron Utilizing Bacteria, Lead Utilizing Bacteria, Lithium Utilizing Fungi, Cadmium Utilizing Fungi, Chromium Utilizing Fungi, Iron Utilizing Fungi, Lead Utilizing Fungi. Results: Enhanced biodegradation and release pattern of heavy metal from spent laptop batteries using Pseudomonas and Bacillus species in freshwater was evaluated and the concentration of heavy metals (Lithium, Cadmium, Chromium, iron and Lead) found associated with the spent laptop batteries (HP, Dell and Acer) were increasing simultaneously with time in all set-ups from day 1 to day 90. The control (without augmenting microbes) has the highest concentration of heavy metals from day 1 to 90 followed by set-ups augmented with Bacillus specie followed by set-ups augmented with Pseudomonas specie, least in set-ups augmented with the consortium of the 2 isolates. The changes in concentration of heavy metals during biodegradation of which Cd < Cr

In the past few years, many have disputed the optimal biomarker for confirming or ruling out a diagnosis of periprocedural myocardial infarction (PMI) and the optimal cut-off concentrations to apply. In this issue of the Journal of Cardiac Surgery, Niclauss et al. performed a retrospective analysis of CK-MB and high-sensitivity cardiac troponin T (hs-cTnT) dynamics and peak concentrations following different cardiac surgical interventions in 400 patients during a 2-year period in a single center. The authors found that CK-MB and hs-cTnT predict PMI with a comparable diagnostic accuracy and discriminatory power >95%. They also attempted to propose an improved, more sensitive threshold of hs-cTnT for PMI. Their findings could have implications for clinical practice, but more research is warranted to identify more appropriate cut-offs. This could include hs-cTnT release pattern, slope steepness, and changes. Ultimately, this could results in patient-specific model, able to predict expected and abnormal ranges of hs-cTnT release, enabling an improved and timely diagnosis of PMI.

Background: Blends of controlled‐release and slow‐release urea may help to synchronize N release from fertilizers and N uptake by maize to improve the plant nitrogen use efficiency. Aim: We aimed to investigate the effects of slow‐release urea and controlled‐release urea and their blends with uncoated urea to release N for maize uptake over time in comparison to urea and ammonium nitrate. Methods: The experiment was performed under greenhouse conditions, and the treatments consisted of conventional urea, ammonium nitrate, three controlled‐release ureas (Multicote 4M®, Nitrocote®, and polyurethane‐coated urea), one slow‐release urea, and mixtures of controlled‐ release urea and slow‐release urea with uncoated urea. These treatments were applied at concentrations of 0, 150, 300, and 450 mg N kg⁻¹ of soil. We evaluated the dry mass, nitrogen accumulation in the shoots, agronomic efficiency index and applied nitrogen recovery after each of three maize croppings. Furthermore, we characterized the N release pattern of the controlled‐release ureas and their coating thicknesses by using scanning electron microscopy. Results: The N release curves showed that Multicote 4M®, Nitrocote® and urea + polyurethane reached 80% of the N released in water at 40°C at 36, 30, and 13 d after incubation. The highest cumulative nitrogen accumulation (1127.4 mg pot⁻¹), agronomic efficiency index (122.3%), and applied nitrogen recovery (69.3%) occurred with ammonium nitrate, with a low residual effect of only 25.4% of the total N accumulated after 35 d of cultivation. The highest cumulative dry mass was produced when the maize was fertilized with a blend in which 40% of the N came from Nitrocote® (44.8 g pot⁻¹). Conclusions: The results showed that ammonium nitrate is an important option as an N source, but it has no residual effect. Controlled‐ release ureas and their blends have a delayed N release and promote constant N uptake after 70 d. After 70 d, the applied N rates were also more important than the N fertilizer technologies. An adequate mixture of N fertilizers could be an interesting option to help synchronize N release and uptake by maize. Technologies involving urea blends could be an option to improve the nitrogen use efficiency in comparison to that obtained by using uncoated urea while decreasing costs in comparison with the application of 100% controlled‐release urea or slow‐release urea.

Dimenhydrinate is a therapeutic agent used for the treatment of nausea and vomiting. A conventional dose of dimenhydrinate is 50 mg per 8 h. Once-daily controlled release tablets of dimenhydrinate were formulated intended to treat emesis. The tablets were formulated using hydrophilic polymers Methocel® and hydrophobic polymers Ethocel® and subsequently analyzed for pre-compression and post-compression characteristics, % moisture uptake, dissolution profiles and release behavior of the drug. Identification of active ingredient and compatibility of blends were analyzed through FT-IR. Drug release kinetics of dimenhydrinate was assessed at pH 1.2, 4.5 and 6.8. The results of release profiles were evaluated for different kinetic models including model dependent and model independent. The optimized formulation K100M 30% showed ideal pre-compression properties and in vitro characteristics. Tablets exhibited a controlled drug release pattern due to the formation of a viscous gel layer followed by erosion. Furthermore, zero-order best described the release pattern with the value of r2 ˃ 0.99. Once-daily tablets released 98–100% drug in 24 h. Significantly more concentration and higher viscosity grade of hydrophilic polymer ensured the required pattern of drug release.

The use of ZnSO4 and FeSO4 either alone or in combination with wood vinegar is incubated to 60 days and it was compared in the present investigation with an aim to increase the nutrient release pattern of micronutrients viz, Fe and Zn under sodic soil conditions. An incubation experiment was conducted during 2019 in ADAC & RI, Trichy, Tamil Nadu. The incubation experiment comprised of 12 treatments replicated twice in a completely randomized design. The treatments included recommended dose of FeSO4 and ZnSO4 alone and their combination and their combination with three levels of wood vinegar viz., 50, 100 and 150 ml/l applied as as spot drenching (SD). Incubated soil sample were analysed for DTPA Zn and Fe at different intervals (0, 15, 30 45 and 60 DAI). The results of the investigation revealed significant differences in wood vinegar release of DTPA Zn and Fe among the treatments in comparison with the ZnSO4 and FeSO4 either alone or in combination of ZnSO4 and FeSO4. Among the treatments, During 0th day of incubation (DAI), the treatment T12 receiving the recommended dose of both ZnSO4 and FeSO4 along with wood vinegar (WV) @ 150 ml/l as spot drenching recorded significantly higher value of available Zn content (46.68 mg kg-1). The lowest value was recorded in the treatment T1 (6.72 mg kg-1) which received recommended dose of FeSO4 alone. At 0th day of incubation (DAI), the treatment receiving recommended dose of ZnSO4 alone (T2) recorded the lowest DTPA Fe (7.32mg kg-1) while the highest value(48.28 mg kg-1) was recorded in the treatment receiving recommended dose FeSO₄ @ 50 kg /ha along with WV @150 ml/l (T6). Therefore, incorporation of wood vinegar increased the effectiveness of Fe and Zn in sodic soils. The release of DTPA Zn and Fe attained peak at 15 DAI and declined thereafter up to 60 DAI. The experiment received that the DTPA Zn and Fe which contributes to available Zn and Fe considerably increased under wood vinegar drenching in sodic soil.

A study was performed to assess nutrient release from biochar inoculated with solid vermicast (SVB), vermicast tea (VTB), deionized water (DWB), uninoculated biochar (Bioc), and Promix-BX (Pro-BX). The growth response of Swiss chard (Beta vulgaris subsp. vulgaris) cv. Rhubarb chard was also assessed. Comparatively, nutrients were released slowly from treatments SVB and VTB compared to the other treatments. The rate of nutrient release determined by total dissolved solids and electric conductivity from the Pro-BX was the highest. The trend for the plant growth components, total leaf surface area and leaf fresh weight at first harvest, was Pro-BX > Bioc > DWB = SVB > VTB. The only treatment that increased total leaf area and leaf fresh weight at the second harvest by approximately 1.02- and 1.88-fold was VTB. Leaf fresh weight was significantly reduced by approximately 0.33-fold for DWB, 0.28-fold for Bioc, and 0.70-fold for Pro-BX but was not altered by SVB at the second harvest as compared to the first harvest. A 2-dimensional principal component analysis (PCA) biplot confirmed that treatment Pro-BX increased plant growth components at the first harvest only. The locations of SVB and VTB on the PCA biplot confirmed their efficacies, which led to increases in the plant growth components at the second harvest. Overall, the VTB adsorbed more nutrients onto its surface that were slowly released to enhance the Swiss chard cv. Rhubarb chard plant growth at the second harvest. Further studies should consider microbial activities.

Soil incubation study in pots was carried out to study the effect of three different biochars on soil moisture retention percentage. The treatments involve three doses of maize biochar (MB), cotton biochar (CB) and prosopis biochar (PB) @ 2.0 t ha-1 (2T), 3.0 t ha-1 (3T) and 4.0 t ha-1 (4T), respectively besides a control and Farm Yard Manure @ 12.5 t ha-1. Significantly higher moisture per cent was noted in treatments of higher doses of all the biochars in second and third day of incubation. The significant increase in moisture per cent was noted in PB 4 T incubated pot, which was followed by CB 4T. The reduction in moisture per cent was noted with lower doses of biochar irrespective of source. Results of another incubation study with different biochars with varied doses, to find out nutrient release pattern revealed that the available N, P and K was higher at the start of incubation in control, where as in later days of incubation N, P and K availability was higher in Prosopis Biochar 4T after 70 days of incubation which was followed by cotton biochar 4T.

The objective of this study was to explore the effect of geometry and tablet design on release pattern of tramadol hydrochloride as a model of freely soluble drug from matrix systems. Hydrophilic and hydrophobic matrices were prepared by direct compression method using HPMC with two different molecular weight and Kollidon® SR as a release-retarding agent respectively at drug: polymer ratio (1:5) for each excipient, in distinct strengths and geometries (i.e. shape, size and dimensions) at parallel and differing surface area to volume ratios. It was found that tramadol release from manufactured tablets is similar when the surface area to volume ratio is equal, regardless of the type of matrix former, drug strength, tablet design. Per contra, the tablet with smaller surface area to volume values had the slower release rate among the same shape. Thus, tablet geometry supplies additional versatility for these systems, making formulators to achieve the desired release characteristics for their drug of option.

Nitrogen (N) fertilizer application is a very important commodity in agricultural systems. However, due to the losses of applied N from the soil microenvironment its efficiency is too low. Different strategies like the use of polymer coating and use of chemical nitrification inhibitors had been employed to reduce N losses. But these chemical nitrification inhibitors are very expensive. Thus, a study was conducted to investigate the effects of different concentrations of parthenium extract, neem oil and acidulated cow dung compost extract on N dynamics in the soil. Three concentrations of parthenium extract (5, 10 and 15 %) and neem oil (1, 2 and 3 %) were coated on urea granules after mixing with the polymer material. Three pH (2, 4 & 6 pH) based acidulated cow dung compost extracts were also coated on urea granules in the same pattern. These coated fertilizers and uncoated urea were applied in jars filled with soil (100g per jar) at the rate of 1g of fertilizer per jar. One treatment was kept as control (without any fertilizer). Treatments along three replications were arranged according to the completely randomized design (CRD). Results depicted that all coating materials caused the release of N consistently from applied fertilizers compared to uncoated treatment. In addition, percent nitrified N was also reduced significantly in coated treatments in comparison to the uncoated urea and control treatments. However, the level of concentration effect was not obvious as lower concentrations of these extracts and oil also performed almost equal to that of higher concentrations.

Background: Development of fortified organic formulations using various organic sources and fertilizers for soil application will ensure efficient nutrient management in homestead vegetable production systems. Fortified organic formulations will help in preventing nutrient leaching also. Hence, the present study has been undertaken during 2019-20 to develop low cost fortified organic manure discs using various biodegradable agro waste materials and NPK fertilizers and to study its effect on growth and yield of tomato in sandy soils of Kerala. Methods: A fortified manure disc was developed by combining local biodegradable agro waste materials with conventional NPK fertilizers. Organic manures like rice husk ash, cow dung, rice husk, coirpith compost, vermicompost, neem cake and clay were used to develop the manure disc. The combination of organic manures was fortified with fertilizers at various proportions of manure: fertilizer viz., 1:1, 2:1, 0.5:1 and manure alone and used for incubation for a period of two months to study the nutrient release pattern of N, P and K.The 2:1(manure: fertilizer) formulation was selected based on the highest peak of nutrient availability of N, P and K even after 2 months. Effect of fortified manure disc was evaluated by using tomato variety Anagha as test crop in a pot culture experiment. Result: Growth, yield and quality of tomato increased significantly due to the application of fortified manure disc. The highest yield per plant of 0.97 kg was recorded for T8 (50% recommended dose fortified manure disc in 2 splits) and lowest yield was recorded for T9 (Manure alone). The fortified manure disc had a significant influence on nutrient use efficiency also. The highest NUE of 45.5% was recorded in treatment T8 (50% fertilizer fortified discs in 2 splits). Study revealed that fortified manure disc is a promising technology to reduce nutrient leaching and enhancing the nutrient use efficiency in sandy soils. Fifty percentage reduction in the recommended dose of NPK fertilizers were achieved by fortifying the manure disc with fertilizers.Thus the cost of fertilizers and fertilizer load per unit area can be reduced by the application of fortified manure disc which will act as slow release fertilizer.

Environmental crises, declining factor productivity, and shrinking natural resource threatened global agricultural sustainability. The task is much more daunting in the Indo-Gangetic northern plains of India, where depletion of the underground water table and erratic rains due to the changing climate pose a major challenge to agriculture. To address these challenges a field investigation was carried out during 2016–18 to test the efficacy of biopolymeric superabsorbent hydrogels namely Pusa Hydrogel (P-hydrogel: a semi-synthetic cellulose derivative-based product) and kaolin derivative of Pusa Hydrogel (K-hydrogel: semi-synthetic cellulose derivative) to assess their effect on crop and water productivity, soil moisture, root dynamics, and economics of soybean (Glycine max L.)–wheat (Triticum aestivum L.) system under three irrigation regimes namely full irrigation, limited irrigation and rainfed. The results revealed that the full irrigation along with P-hydrogel led to enhanced grain yield, biomass yield, and water productivity (WP) of soybean (1.61–10.5%, 2.2–9.5%, and 2.15–21.8%, respectively) and wheat (11.1–18.3%, 12–54% and 11.1–13.1%, respectively) over control plots. The best performance of P-hydrogel was observed under full irrigation compared to K-hydrogel (both at 2.5 and 5.0 kg− 1) and control. Plots treated with P-hydrogel retained 3.0–5.0% higher soil moisture compared to no-hydrogel plots, while K-hydrogel treated plots held the lower moisture (4.0–6.0%) than the control. In terms of profitability, full irrigation along with P-hydrogel plots registered 12.97% higher economic returns over control. The results suggested that full irrigation along with P hydrogels (2.5 kg ha− 1) is a viable option for sustainable production of soybean-wheat systems in the Indo-Gangetic plains of India and other similar eco-regions of the world.

The major constraint in the promotion of organic farming, a safe and sustainable alternative, is lack of availability of quality organic resources in sufficient quantities. The quality of resources...

Clotrimazole (CLT) was formulated in a multiple W/O/W emulsion (ME) with the aim of evaluating its potential as topical anticandidal agent and comparing with marketed products. A previously evaluated CLT-ME was selected and physicochemically characterized. The in vitro release behavior and the ex vivo permeation profiles were assessed using Franz diffusion cells using three different types of biological membranes: human skin and porcine buccal, sublingual and vaginal mucosae. The antifungal activity against Candida strains was also tested. Results showed CLT-MEs sizes of 29.206 and 47.678??m with skin compatible pH values of 6.47 and 6.42 exhibiting high zeta potential values of -55.13 and -55.59?mV with dependence on the pH variation. The physicochemical stability was kept for a period of 180 days of storage at room temperature. CLT-MEs exhibited pseudoplastic behavior with hysteresis areas and viscosities of 286 and 331 mPa?s showing higher spreadability properties than commercial counterparts. An improved CLT release pattern was supplied by the ME system following a hyperbolic model. Likewise, ME system gave higher skin permeation flux of CLT than commercial reference. CLT amounts retained in the skin and mucosae were also higher than commercial references, which coupled with the higher antimycotic efficacy make CLT-MEs a great tool for clinical investigation of topical candidiasis treatments., Supplementary material related to this article can be found, in the online version, at doi: https://doi.org/10.1016/j.colsurfb.2018.11.070., info:eu-repo/semantics/publishedVersion

This study aims to assess the decomposition of manure biodegraded by fly larvae and the nutrient mineralization rates to understand the efficiency of the biodegraded manures for further use as soil amendment. A litter bag experiment was carried out over 75 d in an Acrisol in Benin using poultry manure, pig manure, mixture of poultry and sheep manure, mixture of poultry and cow manure, and mixture of poultry and pig manure, biodegraded by Musca domestica larvae. Nutrients content in the manures during the different stages of decomposition was analyzed. The mono-component exponential model Yt = Y0 × e−kt best described the manure decomposition and nutrients mineralization. The manures decomposed fast in the soil, and their nutrients were released fast in the poultry manure, the mixture of poultry and pig manure, and the mixture of poultry and cow manure. Nutrient mineralization increased in the order of P

Fly larvae are increasingly being promoted as animal feed and their production on agro-processing by-products generates a high amount of residues. Understanding the decomposition and nutrients rele...

An experiment was conducted to determine the effects of vermicompost, inorganic fertilizers and their combinations on release of soil nutrients at different growth stages of wheat. A factorial combination of four levels of inorganic fertilizers (0, 33.33, 66.66, and 100% of the recommended NPK fertilizers) and vermicompost (0, 2, 4 and 6 t ha-1) were laid out in complete randomized design with three replications. Soil was collected before planting and after planting (at tillering, flowering and maturity stages of wheat) from each pot in order to determine dynamics of selected nutrients (NPK). The interaction between vermicompost and chemical fertilizers were not significant for NPK contents of the soil at all growth stages except phosphorus at heading stage. In all cases, highly significant increases in total N, available P and K in the soil were observed due to the increasing rates of main effect vermicompost or inorganic fertilizers during all growing periods. The highest available as well as total contents of NPK in the soil were found at tillering stage. This initial increment at tillering stage for both factors showed a declining trend later at heading and maturity stages. However, the observed decline was in exception for vermicompost applied at 6 t ha-,1 which maintained highest level of available P and K and 4 t ha-1 which continued mineralization of K up to heading stage. In general, application of 6 ton vermicompost per hectare was found proportional with the full dose of the recommended fertilizers in supplying NPK for wheat crop. Therefore, building up the total as well as available NPK to higher levels up to heading stage can bring maximum nutrient uptake and yields of wheat. Key words: Growth stages, mineralization, nutrient availability, nutrient decline.

AIM The aim of this study was to evaluate the force-release behavior of closed coil nickel-titanium springs of three different commercial brands available on the market, as well those from different batches, tested over multiple distances, according to the number of deactivations. MATERIALS AND METHODS For this in vitro analysis, closed coil nickel-titanium springs of the following numbers and brands: eight, 3 mm GAC® springs; eight, 3 mm springs from TP Orthodontics® and eight, 5 mm springs from MORELLI® were standardized at 200 gf force. Two batches of all three brands were tested and compared. All springs were evaluated on a test machine and extended to a distance of five times beyond their original length. The springs were extended, and the distances of force released were measured and marked at every 20% of the total spring length, during their deactivation, and the process was repeated five times for each spring. RESULTS The intraclass correlation coefficients showed that the value of 200 gf indicated by the manufacturers was poorly reproduced. The springs did not change their force release after successive extensions. All springs presented higher deactivation force values as their stretching increased. CONCLUSION All springs presented the greater release of force as their stretch was increased, but the GAC® brand springs presented a more uniform pattern. TP Orthodontics® springs exhibited an acceptable force release pattern, but MORELLI® springs proved to be far below expected strength. CLINICAL SIGNIFICANCE As a clinical consideration of the study, the results obtained in the present research are relevant to the use of nickel-titanium closed springs with regard to the quantity of force released during the mechanics of space closure after extraction (main application of nickel-titanium closed springs), and to the pattern of forces released by springs in view of the real context of gradual closure of spaces after tooth extractions.