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[Display omitted] • Real-time in-line prediction of drug loading of diclofenac sodium during the coating process of sugar spheres was realized by NIRS. • Real-time in-line prediction of release rate during the coating process of diclofenac sodium spheres was realized by NIRS. • The real-time in-line prediction research on drug loading and release rate were carried out with the CQAs of coating process in the fluidized bed. • The analytical ability of the real-time in-line NIRS models of drug loading and release rate was verified by independent external validation set. The preparation of diclofenac sodium spheres by fluidized bed is a common production mode for the pharmaceutical preparations at present, but the critical material attributes in the production process is mostly analyzed off-line, which is time-consuming and laborious, and the analysis results lag behind. In this paper, the real-time in-line prediction of drug loading of diclofenac sodium and the release rate during the coating process was realized by using near infrared spectroscopy. For the best near infrared spectroscopy (NIRS) model of drug loading, R2 cv , R2 p , RMSECV, RMSEP were 0.9874, 0.9973, 0.002549 mg/g, 0.001515 mg/g respectively. For the best NIRS model of three release time points, the R2 cv , R2 p , RMSECV and RMSEP were 0.9755, 0.9823, 3.233%, 4.500%; 0.9358, 0.9965, 2.598%, 0.7939% and 0.9867, 0.9927, 0.4085%, 0.4726% respectively. And the analytical ability of these model was verified. The organic combination of these two parts of work constituted an important basis for ensuring the safety and effectiveness of diclofenac sodium spheres from the perspective of production process. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate, in comparison to the reference product, the effect of the hydrophilic nonionic polymers: methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC), as well as the anionic polymers - copolymers of acrylic acid, on the release kinetics of a calcium dobesilate hydrogel formulation intended for application on the skin. In this work, we used an ointment cell for the release of the active pharmaceutical ingredient (API) from the formulations. This release was performed by employing the paddle method at 100 rpm, with the extraction cells placed in the release vessels in two different positions: with the semipermeable membrane faced to the top, or to the bottom of the vessel. Released API percentage was assessed via the validated spectrophotometric method. In the study with standard placement of the ointment cell, the release rates ranged from 4.45×10-3 min-1 for a formulation containing polyacrylic acid (PA), to 6.96 × 10-3 min-1 for a formulation based on HPMC. In the group of nonionic polymers, the release rate is higher in the case of HPMC, and lower in the case of MC. In the group of anionic polymers, the release rate is higher with the formulation of a modified copolymer of acrylic acid 11 (PC11), while release from a formulation comprising a polymer PA is rather prolonged. We found that the placement of the extraction cell does not affect the alignment of the formulations investigated in terms of the release rates in the group of non-ionic formulations: HPMC > MC, and in the group of preparation of ionic polymers: PC11 > PA.

Naproxen is a poor water soluble, non-steroidal analgesic and anti-inflammatory drug. The enhancement of oral bioavailability of poor water soluble drugs remains one of the most challenging aspects of drug development. Although salt formation, solubilization and particle size reduction have commonly been used to increase dissolution rate and thereby oral absorption and bioavailability of low water soluble drugs, there are practical limitation of these techniques. However, the most attractive option for increasing the release rate is improvement of solubility through formulation approaches. In this study, solid dispersions (SD) of naproxen were prepared by hot melt method using various ratios of drug to polymers (PEG6000) separately and characterized for physical appearance, FTIR, DSC, X-Ray crystallography, and in-vitro dissolution studies. The influence of several amounts of Labrafil M2130 was also studied. FTIR study revealed that drug was stable in SDs, and great state of amorphous formed particles was proofed by DSC analysis. The in vitro dissolution studies were carried using USP type II (paddle) dissolution apparatus at medium (pH 1.5). Solubility of naproxen from SDs was increased in dissolution media. The prepared dispersion showed increase in the dissolution rate of naproxen comparing to that of physical mixtures of drug and polymers and pure drug. Percent of drug released in 60 minutes was 23.92% for pure naproxen witch is increased in SDs and reached to100% for best formulations of PEG6000 and labrafil based SDs respectively, considering ratio of drug to polymers.It is concluded that dissolution of the naproxen could be improved by the solid dispersion. Although physical mixtures have increased the rate of dissolution, dissolution shows faster release from SDs which would therefore be due to formation of amorphous particles through the hot melt process which was also revealed by DSC analysis and XRD.

The human MDR1 gene encodes for a P-glycoprotein (PGP), which acts as an efflux pump that transports a large variety of substrates from the inside of cells to the outside until protection against xenobiotics. The G2677T/A polymorphism in exon 21 is associated with PGP expression and function in humans. The present study was aimed to determine the frequencies of this polymorphism in a healthy population from Mazandaran province of Iran. A total of 120 unrelated healthy subjects from Mazandaran province, residing in Sari, coming for blood donating at Sari Blood Transfusion Center were enrolled. Genomic DNA was extracted from the peripheral blood lymphocytes of each subject. All subjects were genotyped for G2677T/A polymorphism by polymerase chain reaction-restriction fragment length polymorphism method. The genotype frequencies were G2677G (65%), G2677T (20.83%), G2677A (14.17%) and TT, AA, TA genotypes were not observed. Moreover, frequency of G allele (82.5%) was significantly (p ˂ 0.05) higher than the T (10.42%) and A (7.08%). This is the first study to investigate the G2677T/A polymorphism of MDR1 gene in population from Mazandaran province of Iran. These data may be relevant for dose recommendation of PGP substrate drugs and can help for individualizing drug therapy of organ transplantation and important diseases such as cancer and AIDS, congestive heart failure and etc.

Leaching tests were carried out in aerobic and anaerobic conditions to assess the 14C released from TRIGA irradiated graphite. Both total 14C and inorganic and organic fractions in the leachant solutions were measured. The experimental results obtained from the leaching tests confirm the low 14C release rate in alkaline environment. Less than 2% of the total 14C inventory in the specimens subject to the leaching tests was released as dissolved species. Both inorganic and organic 14C species are released in alkaline conditions, with more inorganic 14C release under aerobic conditions (around 68% of the total 14C released was released as inorganic dissolved species), and more organic 14C species in anaerobic conditions (around 65% of the total 14C released was released as organic dissolved species). Both for anaerobic and aerobic conditions, the leaching rates are high in the first days of immersion and decrease after that, indicating a two stage process: an initial quick release (less than 9 × 10–02 % of inventory/day for the first 48 days) followed by a slower release rate (around 4 × 10–03 % of inventory/day). [ABSTRACT FROM AUTHOR]

Methods to determine nutrient release rates of coated fertilizers usually rely on chemical analyses, which often are time-consuming and/or expensive. Our goal was to develop an innovative and rapid low-cost method to evaluate nutrient release from polymer coated MAP or urea using conductometry. The release in water is determined by measuring the electric conductivity (EC) over time, with intervals dependent on release rates. In the case of soluble salt fertilizers, EC can be immediately determined and converted to a concentration using a calibration curve. In the case of urea, an additional step is needed to convert the neutral urea into ammonium. The release rates in water were assessed for a range of commercial and laboratory-coated fertilizers. A validation test demonstrated strong agreement with the release determined using analytical techniques. The EC method hence offers an easy way to quickly evaluate the time course of release of nutrients from controlled-release fertilizers. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • PLGA microspheres were combined with thermosensitive hydrogel to prepare the multilayer sustained release drug delivery system. • The hydrogel micelles and EXT form the unstable complexes. • The biological activity of drug was protected by multi-gel-core structure. • Drug release rate was controlled by multilayer structures. Abstract Traditional polypeptide-loaded PLGA microspheres (PM) using emulsion electrospray techniques often exhibit unsteady release and limited bioactivity. To solve these two problems, an Exenatide (EXT)-loaded multilayer system composed ofPM and thermosensitive hydrogel was prepared by the emulsion electrospray technique in this study. Hydrogel mixture were loaded in PLGA microspheres as Depot-hydrogel to prepare Gel/PM. The PM/Gel and Gel/PM/Gel systems were obtained by dispersion of PM and Gel/PM into hydrogel mixture, respectively. EXT in Gel/PM/Gel showed a constantly in vitro release for 30 days, which was significantly enhanced in comparison of those in the PM/Gel and the Gel/PM. PM/Gel and Gel/PM/Gel showed diminished burst release and no platform period compared with PM and Gel/PM. And these could be because the introduced Matrix-hydrogel outside, as a buffer layer, inhibited burst releases and exhibited a sustained manner. The inner Depot-hydrogelstructure slowed the PLGA degradation rate and drug release rate. As well, more than 15-day blood glucose levels in KKAy mice were greatly maintained at 7.50–9.50 mmol/L after a single subcutaneous injection of Gel/PM/Gel (4.95 μg/kg). Spatial stability and further bioactivity of released EXT were well protected by EXT-hydrogel complexes, and undesirable uptake of EXT and microspheres via phagocytes were also decreased by PEG shell. Thus, the long-acting microspheres/hydrogel multilayer system prepared by emulsion electrospray technique showed promising potentials for loading hydrophilic polypeptides and proteins. [ABSTRACT FROM AUTHOR]

High density polyethylene/low density polyethylene (LDPE) antioxidant multilayer films were prepared by the co-extrusion method, and quercetin was incorporated in the LDPE layers as an antioxidant. The release rates of quercetin and the antioxidant activities of films were adjusted by changing the amount of ethylene vinyl acetate (EVA) and diatomite added into the LDPE active layer. The morphologies of the films were observed by SEM, and the release property of quercetin was characterized by a high-performance liquid chromatography (HPLC) method. The mechanical properties and heat sealing performance of the films were influenced to a certain extent by the amounts of EVA and diatomite in the active layers, while the barrier properties of the films were almost unchanged. The release of quercetin from the active films to a food simulant (95% alcohol) at 37°C was measured over 55 days. When the EVA amounts were 30% and 40% to 50%, the diffusion coefficients, D, were 10-14 and 10-13 cm2/s, respectively. In addition, the antioxidant activity values of the films were enhanced as the EVA amount increased. When adding diatomite into the active layer with 50% EVA, the diffusion coefficient, D, was 10-11 cm2/s, and the quercetin was almost completely released with a partition coefficient, K, of less than 1. Meanwhile, the antioxidant activity values of the films exceeded 95%. The antioxidant release rate could be adjusted within a wide range; thus, these active films could be used for food antioxidant protection. [ABSTRACT FROM AUTHOR]

How zinc oxide influences copper release has been tested and the lowest release rate of copper from various combinations of copper and zinc in a paint matrix evaluated, whilst still deterring macrofouling, including barnacles and bryozoans. Copper (I) oxide was added to a generic AF paint in 0, 8.5, 11.7 or 16.3 wt% copper oxide in combination with 0, 10 or 20 wt% zinc oxide and applied on PMMA panels. The results show that zinc influences the release rate of copper. When 10 and 20 wt% zinc was added, the total amount of copper released significantly increased by on average 32 and 47% respectively. All treatments that included copper were successful in deterring macrofouling, including the treatment with the lowest average Cu release rate, ie 4.68 μg cm−2 day−1. [ABSTRACT FROM AUTHOR]

As part of a broader study of the environmental geochemistry behavior of vanadium (V), the release kinetics of V from the dissolution of natural vanadium titano-magnetite under environmentally relevant conditions was investigated. In both the acidic and basic domains, the V release rate was found to be proportional to fractional powers of hydrogen ion and dissolved oxygen activities. The dependence of the rate on dissolved oxygen can also be described in terms of the Langmuir adsorption model. The empirical rate equation is given by: r = k ′ α H + α Kα O 2 1 + Kα O 2 where, α = 0.099–0.265, k′ = 3.2 × 10 − 6 –1.7 × 10 − 5 , K = 2.7 × 10 4 –3.9 × 10 4 mol/L in acid solution (pH 4.1), and α = − 0.494 − (− 0.527), k′ = 2.0 × 10 4 –2.5 × 10 − 11 , and K = 4.1 × 10 3 –6.5 × 10 3 mol/L in basic solution (pH 8.8) at 20°C. Based on the effect of temperature on the release rate of V, the activation energies of minerals at pH 8.8 were determined to be 148–235 kJ/mol, suggesting that the dissolution of vanadium titano-magnetite is a surface-controlled process. The presence of Na + , Ca 2 + , Mg 2 + , K + , NO 3 − , Cl − , SO 4 2 − and CO 3 2 − was found to accelerate the V release rates. This study improves the understanding of both the V pollution risk in some mine areas and the fate of V in the environment. [ABSTRACT FROM AUTHOR]

Abstract: Citrus essential oils (CEOs) loaded in chitosan microcapsules ( CS-CEOs ) were prepared by 6 different emulsifiers (Tween 20, Tween 40, Tween 60, Tween 20/Span 801:1, Tween 20/SDBS1:1, Span 80) with emulsion-ionic gelation technique. Their rheological properties, embedding and release rate as well as microcapsules diameters were analyzed. The results indicated that emulsifier types significantly affected the size and embedding efficiency of microcapsules, obtaining sample groups of Tween 60, Span 80, Tween 20/Span 80 with typical diameters 289.3 nm, 3893.2 nm, 8843.2 nm, respectively. The structures and thermal properties of CEOs microcapsules were analyzed by using fourier transform infrared spectrophotometry (FT-IR), X-ray diffractometry and differential scanning calorimetry (DSC). Results demonstrated that CEOs oil were successfully embedded in the microcapsules and group of Tween 60 has the minimum particle size with the best embedding rate of 68.1%. The strength of the intermolecular interaction as well as exothermic peaks of microcapsules prepared with different emulsifiers were different, Tween 60 holds the lowest temperature value of exothermic peak for smallest internal energy is needed for melting, corresponds with its lowest particle size. Fourier transform infrared spectroscopy (FT-IR) provided profiles on the major functional groups of CS-CEOs. The results proved condition to prepare CS-CEOs microcapsules by using different emulsifiers. [ABSTRACT FROM AUTHOR]

Returning of biomass ash as fertilizer to field plays great role in sustainable utilization of biomass as energy. In the fertilizer application, release rate of nutrients from ash should be controlled to avoid nutrients shock to plants. Making ash into briquettes (granulated ash, pellet, tablet) is a good choice to slow down the release rate of nutrients and prevent dust formation. However, experimental or theoretical analysis of the release behavior of nutrient from ash briquette is scarce. In this paper, different sizes (from Ф6 mm × 2 mm to Ф15 mm × 5 mm) of tablets of biomass ash were made and their nutrient release behavior was investigated experimentally. Results showed that the release rate of potassium in tablet ash was about 1/20-1/60 of that in the powder ash. And that changing tablet size in the normal size range could not decrease the nutrient release rate to the value required by the norm for slow-release fertilizer. Based on the experiments, the mathematical description of the nutrients release process was established and a Matlab code was written for modelling. The theoretical model was validated and parameters required to make slow release fertilizer from the ash were predicted. It showed that, in order to produce slow release potassic fertilizer, much bigger tablet size (from Ф15 mm × 5 mm to Ф210 mm × 70 mm), much lower saturated concentration (from 0.17 to 0.17/14 2 kg/kg water for potassium), or much smaller effective diffusion coefficient (from 3.2 × 10 −10 to 1.6 × 10 −12 ) are necessary. The theoretical model can be generalized to describe the release behavior of any nutrient and can be used in the parameters optimization for producing slow/control-release fertilizer. [ABSTRACT FROM AUTHOR]

In this study, bovine serum albumin (BSA) and alginate (ALG) conjugates were synthesized by the Maillard reaction in order to evaluate their potential to develop controlled release drug delivery systems. The progress of the Maillard reaction was evidenced using ultraviolet (UV) absorbance, determination of BSA remaining free amino groups, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). BSA-ALG conjugates possessed enhanced and tunable viscosity, foamability and foam stability. Foam generated from BSA-ALG conjugate solution was used to prepare floating gastroretentive calcium ALG beads. Unlike traditional ALG beads, BSA-ALG foam beads were able to float and sustain the ciprofloxacin (CIP) release in gastric medium. Interestingly, intestinal beads made of ALG, BSA-ALG physical mixture and BSA-ALG conjugate resulted in different release rates and orders of indomethacin (IND) in simulated intestinal fluids; while beads based on a physical mixture of BSA-ALG resulted in a first order sustained release profile, both systems based on ALG and BSA-ALG conjugate displayed zero order sustained release profiles with IND being released at a slower rate from the conjugate beads.

The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is an exotic pest of economic importance in several parts of the world. Systems for monitoring this pest employ mainly trimedlure (TML), a parapheromone specifically for males. Understanding the performance of these attractants under different conditions should contribute to better design trapping networks, better field data interpretation, and a more efficient use of the products. In this study, the release rate of TML was determined at 15, 25, and 35 °C, through plug weight loss over 80 d in a bioclimatic chamber. The attraction of TML of different ages was determined in field cage tests located in a mango orchard. Our results showed a direct relationship between TML release rate and temperature. Attraction was dependent on release rate. We found that TML storage for >4 yr at 27 °C affected the quantity of the active ingredient available for release. The results are discussed in terms of the effects of these conditions on the effi- ciency of trapping networks used for the detection of this pest and quality assurance for detection programs. [ABSTRACT FROM AUTHOR]

Several studies have shown an association between dampness and health issues like headache and asthma. To better understand the exposure risk of fungal growth in buildings this study investigates the release of fungi from gypsum boards infested with fungi from a moisture-damaged house. Further, the composition and concentration of fungal species in indoor air of five non-moisture-damaged homes are analysed, and the ratio between species associated- and not associated with moisture-damaged buildings are related to air change rate (ACR) and relative humidity (RH). The air velocity near the surface of the gypsum boards in combination with the changes in sampling time influenced the particle release rate. After 8 h particles were still released, and more species were released during 8 h with low air velocity than during 15 min with high air velocity. More fungal species and a higher release rate were found from damp surfaces with substantial growth than from gypsum boards dried out before they were totally colonized. In the five homes ACR and RH had a significant influence on the fungal species composition. Thus, a low ACR and a high RH were associated with increased ratio of species associated with moisture-damage relative to species not associated with moisture-damage. In conclusion, increasing the ventilation and reducing the RH of the indoor air will have a beneficial effect on the airborne species composition. Further, fast action by drying out a fungal infestation has a positive impact on the exposure risk in terms of exposure level and species composition. [ABSTRACT FROM AUTHOR]

The use of nanoporous anodic alumina (NAA) for the development of drug delivery systems has gained much attention in recent years. The release of drugs loaded inside NAA pores is complex and depends on the morphology of the pores. In this study, NAA, with different three-dimensional (3D) pore structures (cylindrical pores with several pore diameters, multilayered nanofunnels and multilayered inverted funnels) were fabricated and their respective drug delivery rates were studied and modeled using doxorubicin as a model drug. The obtained results reveal optimal modeling of all 3D pore structures, differentiating two drug release stages. Thus, an initial short-term and a sustained long-term release were successfully modeled by the Higuchi and the Korsmeyer-Peppas equations, respectively. This study demonstrates the influence of pore geometries on drug release rates and further presents a sustained long-term drug release that exceeds 60 days without an undesired initial burst. [ABSTRACT FROM AUTHOR]

Drosophila suzukii Matsumura, spotted wing drosophila, can be trapped with a feeding attractant based on wine and vinegar volatiles and consisting of acetic acid, ethanol, acetoin, and methionol. Using that fourcomponent blend, we found that the catch of spotted wing drosophila increased with increases in the release rate of acetoin (from 0.5 mg/d to 34 mg/d) from polyethylene sachet dispensers, and with increases in the concentrations of acetic acid (from 0.25% to 4%) or ethanol (from 0.08% to 2%) when dispensed in the trap drowning solution. However, we saw no increase in spotted wing drosophila trapped with increase of the methionol release rate from 0.4 mg/d to 4.9 mg/d or from 0.19 mg/d to 0.8 mg/d, from sachets. A new formulation based on optimized amounts of these four chemicals yielded a doubling of spotted wing drosophila trapped compared to a previously reported formulation. Further field testing confirmed that the simultaneous increases in the release rate of acetoin from a dispenser and the amount of acetic acid in the trap drowning solution provided the increased spotted wing drosophila trap response to the new formulation. These findings provide a practical means to improve the power of this lure to detect and monitor D. suzukii. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) is an endogenously produced gasotransmitter in mammals, and may have signaling roles in bacteria as well. It has many recognized therapeutic effects. A significant challenge in this field is the development of pharmaceutically acceptable forms of CO delivery with controllable and tunable release rates. Herein, the structure-release rate studies of the first class of organic CO prodrugs that release CO in aqueous solution at neutral pH is described. [ABSTRACT FROM AUTHOR]

The investigation of semisolid ophthalmic ointments is challenging due to their complex physicochemical properties and the unique anatomy of the human eye. Using Lotemax ® as a model ophthalmic ointment, three different manufacturing processes and two excipient sources (Fisher ® (OWP) and Fougera ® (NWP)) were used to prepare loteprednol etabonate ointments that were qualitatively and quantitatively the same across the manufactured formulations. Physicochemical properties including drug content and uniformity, particle size and distribution, as well as rheological parameters (onset point, crossover modulus, storage modulus and Power law consistency index) were investigated. In addition, USP apparatus 2 with enhancer cells was utilized to study the in vitro drug release characteristics of the ophthalmic ointments. Both manufacturing processes and excipient sources had a significant influence on the physicochemical attributes and the in vitro drug release profiles of the prepared ointments. Ointments prepared via the hot melt processes exhibited higher rheological parameters and lower drug release rates compared to ointments prepared without hot melting. Ointments prepared with OWP demonstrated higher rheological parameters and lower in vitro drug release rates compared to ointments prepared with NWP. A strong correlation between the rheological parameters and in vitro drug release rate was shown using logarithmic linear regression. This correlation may be useful in predicting in vitro drug release from measured physicochemical properties, and identifying the critical quality attributes during the development of ointment formulations. [ABSTRACT FROM AUTHOR]

Clogging of constructed wetlands commonly occurs; however, clogging of horizontal subsurface-flow constructed wetlands (HSSFCW) has not been successfully simulated using mathematical models. This study established a mathematical model by coupling one-dimensional mass transfer model with multicomponent biochemical reactions by using Constructed Wetland Model No. 1 to simulate clogging during treatment of domestic sewage with HSSFCW. Complex relations among porosity, hydraulic conductivity, and retention capability of particles were dodged dexterously in the new model by using total particle concentration within interstitial space as indicator of clogging. Introducing particulate component release ratio, which controlled the transmission of particles within substrates, and using substrate porosity as constant simplified the simulation and saved computation time. Clogging degree can be easily identified by comparing total particle concentration in the interstitial space with the concentration threshold of clogging, such as biofilm density. The value of particulate component release ratio was determined, and the model was calibrated using measured data from the literature. Results showed that the proposed model can successfully simulate clogging and explain the underlying mechanism of HSSFCW. The new model supplied a simple method for predicting the clogging of HSSFCW. [ABSTRACT FROM AUTHOR]

Generally, although the conventional drug delivery systems, such as using only pH-dependent polymers or time-dependent release systems are popular, the individuals’ variations of physiological conditions usually lead to premature or imperfect drug release from each of these systems. Therefore, a combination of pH- and time-dependent polymers could be more reliable for delivering drugs to the lower GI tract such as colon. To this end, electrospinning method was used as a fabrication approach for preparing electrospun nanofibers of indomethacin aimed for colon delivery. Formulations were prepared based on a 3 2 full factorial design. Independent variables were the drug:polymer ratio (with the levels of 3:5, 4.5:5 and 6:5 w/w) and Eudragit S:Eudragit RS w/w ratio (20:80, 60:40 and 100:0). The evaluated responses were drug release at pH 1.2, 6.4, 6.8 and 7.4. Combinations of Eudragit S (ES), Eudragit RS (ERS) and drug based on factorial design were loaded in 10 ml syringes. Electrospinning method was used to prepare electrospun nanofibers from electrospinning solutions. Conductivity and the viscosity of the solutions were analyzed prior to electrospinning. After collection, the nanofibers were evaluated in terms of morphology and drug release. It was shown that the ratio of drug:polymer and polymer:polymer were pivotal factors to control the drug release from nanofibers. A formulation containing Eudragit S:Eudragit RS (60:40) and drug:polymer ratio of 3:5 exhibited the most appropriate drug release as a colon delivery system with a minor release at pH 1.2, 6.4 and 6.8 and major release at pH 7.4. Nanofibers resulted from this formulation were also more uniform and contained fewer amounts of beads. It was demonstrated that the electrospinning could be regarded as a modern approach for the preparation of colon drug delivery systems leading to marketable products. [ABSTRACT FROM AUTHOR]

Attraction of California red scale males,Aonidiella aurantii(Maskell), to different release rates of the sex pheromone compound 3-methyl-6-isopropenyl-9-decen-1-yl acetate was evaluated in field trials. This study was aimed to study pheromone emission-response correlations and the existence of an optimum release rate that maximizes trapping efficacy. Release profiles of the pheromone dispensers deployed were determined by gas chromatography to estimate the various emission rates tested. The results reveal that the mean number ofA. aurantiimales caught correlates with the daily pheromone release rates by means of a quadratic model. The obtained model indicates the existence of a relative maximum of the captures corresponding to an optimum release rate of ca. 300 μg/day. Higher emission rates (up to 1 g/day) resulted in lower captures. Implications for the mating disruption technique are discussed. [ABSTRACT FROM AUTHOR]

Fecal indicator organisms (FIOs) are generally believed to be present in surface waters due solely to direct deposition of feces or through transport in runoff. However, emerging evidence points toward hyporheic exchange between sediment pore water and the overlying water column during baseflow periods as a source of FIOs is surface waters. The objective of this work was to (a) propose a mass balance-based technique for estimating changes of FIO concentrations in the same volume of water (or 'slug') from the inlet to outlet of stream reaches in baseflow conditions and (b) to use such enumeration to estimate rate of the FIO release to stream water column. Concentrations of Escherichia coli ( E. coli) and enterococci were measured in the slug while simultaneously monitoring the movement of a conservative tracer, Br that labeled the slug. Concentrations of E. coli in the slug were significantly larger ( P = 0.035, P = 0.001, and P = 0.001, respectively) at the outlet reach in all three replications, while enterococci concentrations were significantly larger in two of three replications ( P = 0.001, P < 0.001, and P = 0.602). When estimated without accounting for die-off in water column, FIO net release rates across replications ranged from 36 to 57 cells m s and 43 to 87 cells m s for E. coli and enterococci, respectively. These release rates were 5 to 20% higher when the die-off in water column was taken into account. No diurnal trends were observed in indicator concentrations. No FIO sources other than bottom sediment have been observed during the baseflow period. FIOs are released into stream water column through hyporheic exchange during baseflow periods. [ABSTRACT FROM AUTHOR]

Fur garments contain residual tetrachloroethylene (PCE) from dry cleaning. Exposure to PCE can be harmful to human skin; thus, it is necessary to determine the amount of residual PCE in garments to ensure safety. This paper reports a fast, simple, and effective method for determining residual PCE using ultrasonic extraction technology combined with gas chromatography-mass spectrometry. The linear correlation coefficient of this method was 0.9999, with a low detection limit of 1.4 mg/kg. Recoveries from sheepskin leather, rabbit fur, fox fur, and raccoon fur ranged from 90.2 to 101.9 %, with relative standard deviations of 2.87-4.87 %. These results confirmed the high precision and accuracy of this new method. Meanwhile, in a simulated standard indoor environment, the 1 day and 18 day release rates for PCE residues on dry-cleaned fur garments were studied by analyzing PCE adsorption on four different materials, resulting in recommendations for storing and wearing different fur garments after dry-cleaning to ensure safety. [ABSTRACT FROM AUTHOR]

To characterize performance of levonorgestrel-releasing intrauterine system (LNG-IUS) 52mg (Mirena) over 8 years of use and facilitate comparisons with LNG-IUS 19.5mg and LNG-IUS 13.5mg. We estimated in vivo levonorgestrel (LNG) release rates and LNG plasma/serum concentrations for LNG-IUS 52mg up to 8 years of use with a population pharmacokinetic (popPK) approach using data from the Mirena Extension Trial (MET) and earlier clinical trials. We compared these with previously published release rates and exposure data for LNG-IUS 19.5mg and 13.5mg. Our 8-year popPK and release models were developed based on measured plasma/serum LNG and sex hormone-binding globulin concentrations and residual LNG content from removed LNG-IUS 52mg devices. Model-based estimated LNG release rates for LNG-IUS 52mg decreased from ∼21 µg/d after insertion to ∼7.0 µg/d after 8 years, similar to LNG-IUS 19.5mg after 5 years (7.6 µg/d) and higher than LNG-IUS 13.5mg after 3 years (5.5 µg/d). Model-based estimated and measured plasma/serum LNG concentrations showed satisfactory agreement. Average model-based estimated LNG concentrations after 8 years of LNG-IUS 52mg use (100 ng/L [coefficient of variance 39.9%]) were similar to LNG-IUS 19.5mg after 5 years (84.8 ng/L [39.9%]) and higher than LNG-IUS 13.5mg after 3 years (58.1 ng/L [40.8%]). The 8-year release and popPK models provide reliable in vivo LNG release rates and concentration estimates, respectively, facilitating direct comparisons between the 3 studied LNG-IUSs. LNG release rates from LNG-IUS 52mg at 8 years are similar to LNG-IUS 19.5mg at 5 years and higher than LNG-IUS 13.5mg at 3 years. Levonorgestrel release from intrauterine system reservoirs declines with duration of use in a predictable way, and in relation to the initial load. As release rates and plasma concentrations of levonorgestrel may influence endometrial and systemic side effects, these data may assist clinical decision-making. [ABSTRACT FROM AUTHOR]

Carvone and spearmint essential oil vapours are suitable candidates for the control of citrus postharvest pathogens due to their strong antifungal activity. However, the high volatility of essential oils remains a hurdle that needs to be overcome before it can be applied as an alternative fungicide. This work investigates the antifungal activity of 20 and 30 wt-% spearmint essential oil or carvone, incorporated into ethylene–vinyl acetate (EVA) and linear low-density polyethylene (LLDPE) strands postharvest pathogens affecting kumquats. Following the melt-extrusion process, an average yield of 16–29 % and 15–28 % of the total carvone and spearmint essential oil, respectively, was determined in the polymer strands. Morphological studies using scanning electron microscopy (SEM) revealed the presence of microporous structures in the internal structure of the strands. The membrane-like skin that covers the polymer strand was also confirmed by SEM. Variations in the release rates were observed between carvone and spearmint essential oils, which was attributed to the difference in the vapour pressure of the neat essential oils. Furthermore, in this study, the results demonstrated that the diffusion exponent ' n ' of the Korsmeyer–Peppas, Weibull and Log-logistic models exceeded 1.0. In most cases, the Super Case II mechanism was observed. In the case of the Mapossa model, as k 2 was ˃> 1, it implies that the outer skin-like membrane covering the polymer strand fully controlled the carvone release. The application of the essential oil-loaded polymer strands resulted in a significant reduction in deterioration, caused by citrus postharvest pathogens, of kumquats kept at room temperature for 21 days. This study indicates that the incorporation of spearmint essential oil or carvone into LLDPE or EVA polymer strands promoted the preservation of kumquat over a 21-day period. [ABSTRACT FROM AUTHOR]

The Graphical abstract talked about the digestion and absorption of carotene and its influencing factors. [Display omitted] • Concepts underlying carotenoids digestion and absorption were clarified. • A standardized system for evaluating carotenoids bioavailability was suggested. • The relevant factors affecting the key process of the digestion and absorption of carotenoids were discussed. The published literature has shown that there are various evaluation methods for the process of carotenoids digestion and absorption. However, it was found that many concepts are ambiguous in the evaluation process, and the selection of evaluation methods is inappropriate and inaccurate. These deficiencies trouble readers, hamper comparisons among different studies, and generate controversy in different literature. Therefore, it is imperative to establish a complete and standardized system for evaluating the digestion and absorption process of carotenoids. This review begins by clarifying confusing concepts during the process of carotenoids digestion and absorption, including the release rate, micellization rate, bioaccessibility, relative bioavailability and absolute bioavailability. Then this review discusses relevant factors affecting the key process of the digestion and absorption of carotenoids. Finally, a more specific and standardized system for evaluating carotenoids bioavailability was suggested based on four dimensions: intake, digestion, absorption and metabolic process. Clarifying concepts such as digestion and absorption and standardizing corresponding research methods will help to obtain reliable data and support interoperability and comparisons across studies. [ABSTRACT FROM AUTHOR]

Aspergillus niger enzyme preparation, locally produced, and six commercial fungal enzyme preparations were assessed for olive oil mill wastewater (OOMW) hydrolytic treatment. The processes performances were evaluated in terms of hydroxytyrosol (HT) and reducing carbohydrates (RC) release yields, and enzyme productivities. Enzymatic hydrolysis of OOMW of the tested enzyme preparations had shown an increase of HT and RC release yields. These ranged between 0.42 and 0.87% (g HT produced/100 g dry matter), and between 3.06 and 9.7% (g RC/100 g dry matter), respectively. The kinetic parameters (maximal release rate and half-saturation constant) determined by an alternative approach to the classical Michaelis-Menten model has shown that produced enzyme preparation had an initial release rate of 0.02 g HT/L min, which is comparable to rates obtained in the presence of Viscozyme L, Novarom Blanc and Peclyve Lif Plus. The antioxidant activity of the ethyl acetate extract of OOMW, measured by the DPPH method, was drastically enhanced after the different enzymatic treatments. This study demonstrates that enzymatic treatment is a potential method for the valorization of OOMW in order to produce valuable compounds with promising applications in the food industry. [ABSTRACT FROM AUTHOR]

The use of nanocarriers is an intriguing solution to increase the brain delivery of novel therapeutics. The aim of this paper was to use pharmacokinetic analysis and simulations to identify key factors that determine the effective drug concentration–time profile at the target site in the brain. Model building and simulations were based on experimental data obtained from the administration of the opioid peptide DAMGO in glutathione tagged PEGylated liposomes to rats. Different pharmacokinetic models were investigated to explore the mechanisms of increased brain delivery. Concentration–time profiles for a set of formulations with varying compound and carrier characteristics were simulated. By controlling the release rate from the liposome, the time profile and the extent of brain delivery can be regulated. The modeling did not support a mechanism of the liposomes passing the brain endothelial cell membrane in an intact form through endocytosis or transcytosis. The most likely process was found to be fusion of the liposome with the endothelial luminal membrane. The simulations revealed that low permeable compounds, independent on efflux, will gain the most from a nanocarrier formulation. The present model based approach is useful to explore and predict possibilities and limitations of carrier-based systems to the brain. [ABSTRACT FROM AUTHOR]