A novel method for the fabrication of polymeric particles on the order of tens of nanometers to several microns is described. This imprint lithographic technique called PRINT™ (Particle Replication In Non-wetting Templates), takes advantage of the unique properties of elastomeric molds comprised of a low surface energy perfluoropolyether network, allowing the production of monodisperse, shapespecific nanoparticles from an extensive array of organic precursors. This engineered nature of particle production has a number of advantages over the construction of traditional nanoparticles such as liposomes, dendrimers, and colloidal precipitates. The gentle "top down" approach of PRINT enables the simultaneous and independent control over particle size and shape, composition, and surface functionality, and permits the loading of delicate cargos such as small organic therapeutics and biological macromolecules. Thus, this single tool serves as a comprehensive platform for the rational design and investigation of new nanocarriers in medicine, having applications ranging from therapeutics to advanced diagnostics. Preliminary in vitro and in vivo studies were conducted, demonstrating the future utility of PRINT particles as delivery vectors in nanomedicine. Monodisperse 200 nm poly(ethylene glycol)-based (PEG) particles were fabricated using PRINT methodology and characterized via scanning electron microscopy and dynamic light scattering. Incubation with HeLa cells showed very little cytotoxicity, even at high concentrations. The biodistribution and pharmacokinetics of [ 125 I]-labeled particles were studied in healthy mice following bolus tail vein administration. The particles were distributed mainly to the liver and the spleen with an apparent distribution t 1/2 of approximately 17 min followed by slow redistribution with a t 1/2 of 3.3 h. The volume of distribution for the central and peripheral compartments was found to be approximately 3 mL and 5 mL, respectively.

(1)H NMR relaxation and diffusion studies were performed on water-in-CO(2) (W/C) microemulsion systems formed with phosphorus fluorosurfactants of bis[2-(F-hexyl)ethyl] phosphate salts (DiF(8)), having different counterions (Na(+), NH(4)(+), N(CH(3))(4)(+)) by means of high-pressure in situ NMR. Water has a low solubility in CO(2) and is mainly solubilized by the microemulsion droplets formed with surfactants added to CO(2) and water mixtures. There is rapid exchange of water between the bulk CO(2) and the microemulsion droplets; however, NMR relaxation measurements show that the entrapped water has restricted motion, and there is little "free" water in the core. Counterions entrapped by the droplets are mostly associated with the surfactant headgroups: diffusion measurements show that counterions and the surfactant molecules move together with a diffusion coefficient that is associated with the droplet. The outer shell of the microemulsion droplets consists of the surfactant tails with some associated CO(2). For W/C microemulsions formed with the phosphate-based surfactant having the ammonia counterion (A-DiF(8)), the (1)H NMR signal for NH(4)(+) shows a much larger diffusion coefficient than that of the surfactant tails. This apparent paradox is explained on the basis of proton exchange between water and the ammonium ion. The observed dependence of the relaxation time (T(2)) on W(0) (mole ratio of water to surfactant in the droplets) for water and NH(4)(+) can also be explained by this exchange model. The average hydrodynamic radius of A-DiF(8) microemulsion droplets estimated from NMR diffusion measurements (25 degrees C, 206 bar, W(0) = 5) was R(h) = 2.0 nm. Assuming the theoretical ratio of R(g)/R(h) = 0.775 for a solid sphere, where R(g) is the radius of gyration, the equivalent hydrodynamic radius from SANS is R(h) = 1.87 nm. The radii measured by the two techniques are in reasonable agreement, as the two techniques are weighted to measure somewhat different parts of the micelle structure.

The solution properties of a fluorinated alkyl methacrylate, poly(1,1,2,2-tetrahydroperfluorooctyl methacrylate) (PFOMA), in liquid and supercritical carbon dioxide (CO 2 ) were studied by static and dynamic light scattering. The solvent quality of CO 2 was found to improve with increasing temperature and CO 2 density as exhibited by an increase of the second virial coefficient. Both the hydrodynamic radius expansion factor and the second virial coefficient of PFOMA solution were found to be functions of a single interaction parameter that can be independently changed by either temperature or density variations. Furthermore, we demonstrate that the relationship between two directly measurable quantities, the second virial coefficient and the hydrodynamic expansion ratio, is the same for both temperature-induced and CO 2 density-induced variations of solvent quality.

ObjectivesSinistral portal hypertension (SPH) is an uncommon complication of chronic pancreatitis (CP) and can result in severe gastrointestinal bleeding. The aim of this study was to determine the prevalence and the potential risk factors for SPH and related gastrointestinal variceal bleeding in patients with CP.MethodsWe retrospectively reviewed all patients with SPH due to CP admitted to our hospital from July 2014 to June 2019 in this case‐control study. Patients with CP without SPH were randomly selected as controls during the study period (case: control  =  1:2). The characteristics, medical history, course of CP, characteristics associated with SPH, and follow‐up evaluations of the patients were documented in detail. The prevalence rate of SPH in patients with CP and related gastrointestinal bleeding was calculated. Risk factors for SPH and related variceal bleeding were analyzed using univariate or multivariate logistic regression analysis.ResultsThe prevalence of SPH was 2.7% (89/3358) in patients with CP. Independent risk factors for SPH included alcohol consumption (P = 0.030), history of acute pancreatitis (P = 0.010), diabetes mellitus (P < 0.001), and pseudocysts (P < 0.001). Overall 17 (19.1%) patients suffered from related gastrointestinal bleeding. Between the bleeding and non‐bleeding groups, there were significant differences in the types of CP, existence of stones, gastric varices diagnosed before bleeding, splenomegaly and hypersplenism by univariate analysis.ConclusionSPH is a rare complication of CP that is associated with a relatively low risk of variceal bleeding.

A 2 × 2 factorial arrangement (rearing room with or without pad-fan cooling × diet with or without 2.5 kg/t organic acid) was used to evaluate the effect of pad-fan cooling and dietary organic acid supplementation during perinatal period on reproductive performance and antioxidant status of sows in hot weather. This study was conducted in a subtropical city in Guangdong Province in South China between August and October, 2015. At day 85 of gestation, a total of 112 sows were randomly assigned to the four treatments with 28 sows per treatment, and maintained until day 21 of lactation, and the feeding trial lasted for 51 days. During the experimental period, room temperature and humidity were recorded hourly. The lactation feed intake of sows (P = 0.109) and stillbirths (P < 0.05) increased when the sows were reared in the room with the pad-fan cooling against the room without pad-fan cooling. The number of weak newborns per litter and the malondialdehyde content in days 14 and 21 milk decreased (P < 0.05), while the lactation feed intake of sows, weaned litter weights, and individual pig weights increased when the sows were fed the organic acid (P < 0.05). In conclusion, pad-fan cooling in rearing room improved the lactation feed intake of sows, and dietary organic acid supplementation improved reproductive performance and milk antioxidant status of sows. Pad-fan cooling is recommended in farrowing room, but not in gestating room.

Nano-ZnO photocatalyst was prepared using direct precipitation method .The crystal form, particle size and configuration characterization of the nano-ZnO prepared was characterized by XRD and SEM. The photocatalytic degradation of ammonia-N in aquaculture wastewater was investigated by using nano-ZnO under UV irradiation. The experimental results show that: nano-ZnO dosage, catalytic reaction time, initial ammonia-N concentration, H2O2volume concentration, pH value affect the efficiency of photocatalytic degradation significantly. On the basis of the results of these experimental data, the optimal experimental conditions for photocatalytic degradation of ammonia-N are tried through the orthogonal test. The optimization experimental conditions for photocatalytic degradation of ammonia-N in aquaculture wastewater are as follows, nano-ZnO catalyst dosage was 0.4 g/L, the pH value of solution was 10, H2O2volume fraction was 4 %, respectively, if the reaction time may last 1 h, the removal rate of ammonia-N was expected to reach 86.66 %.

A study was conducted to evaluate the effects of feeding an acidogenic diet with a low dietary cation-anion difference (DCAD) on acid-base balance, blood, milk, and urine Ca concentrations of sows during lactation. A total of 30 multiparous sows (parity: 4.5 ± 2.9, Smithfield Premium Genetic, Rose Hill, NC) were allotted to 1 of 2 dietary treatments: CON (control diets were corn-soybean meal based with a calculated DCAD of 170 and 226 mEq/kg during late gestation and lactation, respectively) or ACI (acidogenic diets had a DCAD 100 mEq/kg lower than the control diets). The lower DCAD was achieved by the addition of an acidogenic mineral. The DCAD was calculated as mEq (Na + K – Cl)/kg diet. Sows had a daily access to 2-kg feed from day 94 of gestation to parturition and ad libitum access to feed during lactation. Blood and urine pH and Ca, serum macrominerals, serum biochemistry, Ca-regulating hormones, and milk composition were measured. Sows in ACI had a lower (P < 0.05) blood pH than sows in CON at day 1 of lactation. Sows in ACI had a lower (P < 0.05) urine pH at day 108 of gestation, days 1, 9, and 18 of lactation compared with sows in CON. Sows in ACI had greater (P < 0.05) concentrations of serum total Ca at days 1 and 18 of lactation than sows in CON. There was a greater (P < 0.05) concentration of colostrum Ca in ACI than in CON. There was no difference in urine Ca concentration between treatments during lactation. Concentrations of parathyroid hormone and 1,25-dihydroxycholecalciferol were not different between treatments at either day 1 or 18 of lactation. Sows in ACI tended to have a smaller (P = 0.086) concentration of total alkaline phosphatase in serum at day 18 of lactation compared with sows in CON. At day 1 of lactation, the concentration of serum Cl in ACI was greater (P < 0.05) than that in CON. Feed intake, BW loss, and litter performance were not different between treatments. Collectively, feeding an acidogenic diet with a low DCAD to sows can induce a mild metabolic acidosis at farrowing, reduce the urine pH consistently, and increase serum total Ca and colostrum Ca concentrations during lactation but without altering the parathyroid hormone and 1,25-dihydroxycholecalciferol levels during lactation.

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