Reference values for Schirmer tear tests I and II in clinically normal pigs

Objective To determine reference values for Schirmer tear tests I and II in clinically normal pigs. Animal studied Twenty clinically normal Landrace pigs (10 males and females) without ocular abnormalities were used in this study. Procedures In all pigs, Schirmer tear tests (STT) I and II were performed by using a sterile Schirmer tear test standardized strip (Schirmer‐Tränentest^®, Germany) placed in the lower conjunctival fornix for 1 min. Results For each test (STT I and STT II), no differences were observed between the right and left eyes (P ≥ 0.5). The mean ± SD STT I value was 15.6 ± 3.7 mm/min (range, 10–22 mm/min), while the mean STT II value was 12.4 ± 3.8 mm/minute (range, 5–18 mm/min). The mean STT II value was significantly lower than the STT I level (P < 0.001). Animal gender did not have a significant effect on STT I and II values (P = 0.52). The mean ± SD STT I/II values of 10 juvenile pigs were significantly lower than the mean ± SD STT I/II values of 10 adult pigs (P < 0.001). Conclusions This study of 20 Landrace pigs provided valuable information on normal STT I/II in this species. Knowledge of normal STT reference values in pigs enables the clinician to evaluate corneal pathology and diagnose tear deficiency syndromes with greater accuracy.     

Intraocular pressure and Schirmer tear test results in clinically normal Long-Eared Hedgehogs (Hemiechinus auritus): reference values

Objective The present study was undertaken to establish reference values for Schirmer tear test (STT) and intraocular pressure (IOP) in the long‐eared hedgehog (Hemiechinus auritus). Animals Fourteen healthy long‐eared hedgehogs (H. auritus) of either sex were studied. Procedures The hedgehogs were individually immobilized with an intramuscular injection of combined Ketamine (20 mg/kg) and Diazepam (0.5 mg/kg), and each animal underwent ophthalmic examinations including: STT, tonometry, biomicroscopy, and indirect ophthalmoscopy. Results No significant effects of animal gender, weight, side (right vs. left eye) were found in this study. Mean (SD) STT values for all eyes (n = 28) were 1.7 ± 1.2 mm/1 min with a range of 0–4 mm/1 min. Mean STT in male animals was 2.2 ± 1.2. Mean STT in female Hedgehogs was 1.3 ± 1.1. Mean (SD) IOP values by applanation tonometry were 20.1 ± 4.0 mmHg (range 11.5–26.5 mmHg). Mean (SD) IOP values by applanation tonometry were 18.2 ± 4.0 and 22.0 ± 3.2 mmHg for males and females, respectively. Conclusions This study reports STT and IOP findings in long‐eared hedgehogs (H. auritus).     

Gas Separation Polysulfone Membranes Modified by Cadmium-based Nanoparticles

This paper presents new mixed-matrix membranes (MMMs) synthesized via incorporating hexamethylenetetramine dicyanamide cadmium nanoparticles, a metal organic framework (MOF), into the polysulfone (PSF) matrix. The MMMs are characterized using FTIR and SEM analyses, and their gas permeation properties are evaluated at different MOF loadings and various pressures. The results show that the nanoparticle is compatible with the polymer and distributes homogenously in the matrix. Compared to the pristine PSF membrane, the MMM with 2.5 wt. % of the MOF nanoparticles has lower CO₂, CH₄, N₂ and O₂ permeabilities but significantly higher CO₂/CH₄, CO₂/N₂ and O₂/N₂ gas pair selectivities (i.e., 41.66, 20.08 and 5.09, respectively, which are 42.6, 61.6 and 60.02 % higher). As the total pressure increases, the gas permeabilities of the pristine PSF membrane and the MMMs decrease, but their sieving abilities increase. These results suggest that gas selectivities of high free-volume polymers with poor sieving abilities can be improved by incorporating the MOF into the polymer.     

A New Approach to Predict Daily pH in Rivers Based on the “à trous” Redundant Wavelet Transform Algorithm

Prediction of pH is an important issue in managing water quality in surface waters (e.g., rivers, lakes) as well as drinking water. The capacity of artificial neural network (ANN), wavelet-artificial neural network (WANN), traditional multiple linear regression (MLR), and wavelet-multiple linear regression (WMLR) models to predict daily pH levels (1, 2, and 3 days ahead) at the Chattahoochee River gauging station (near Atlanta, GA, USA) was assessed. In the proposed WANN model, the original time series of pH and discharge (Q) were decomposed (after being split into training and testing series) into several sub-series by the the à trous (AT) wavelet transform algorithm. The wavelet coefficients were summed to obtain useful input time series for the ANN model to then develop the WANN model for pH prediction. The redundant à trous algorithm was used for data decomposition. Model implementation indicated the values of 1-day-ahead pH predicted by the WANN model closely matched the observed values (with a coefficient of determination, R²?=?0.956; Root Mean Square Error, RMSE?=?0.019; and Mean Absolute Error, MAE?=?0.015). It is therefore possible that the WANN model’s accuracy can be attributed to its better predictive ability (due to the use of the AT) to remove the noise caused by pH shifts (e.g., acid precipitation). Peak pH values predicted by the WANN model were also closer to observed values compared to the other machine learning models.     

Comparisons of commercial organic and chemical fertilizer solutions on growth and composition of lettuce

The objective of this experiment was to assess the effects of organic or chemical nutrient solutions on the growth and composition of lettuce (Lactuca sativa L.) in greenhouse production. Hoagland and Arnon nutrient solution, an organic hydroponics solution, and no fertilization were factored with lettuce cultivars of different phenotypes, iceberg, romaine, loose head, and loose leaf. Lettuce growth was higher with Hoagland and Arnon solution than with the organic fertilizer or with no fertilization. The organic fertilizer increased growth above no fertilizer applied. Hoagland and Arnon solution gave the highest concentration of nitrogen, potassium, magnesium, and iron in the lettuce whereas lettuce grown with the organic fertilizer had the highest phosphorus. Plant nutrient accumulation differed slightly among the cultivars. Hoagland and Arnon solution produced high nitrate in leaves. Nitrate concentrations with organic or no fertilization were low. Loose head or loose leaf cultivars had higher nitrate than romaine or iceberg.     

Biomass and nutrient concentration of lettuce grown with organic fertilizers

The responses of lettuce (Lactuca sativa L. ‘Arroyo’) to organic nitrogen (N) fertilizers were investigated in a greenhouse. Fertilizers were blood meal (BLO), feather meal (FM), cottonseed meal, alfalfa meal, sewage sludge, compost, cow manure, a chemical fertilizer, and a treatment without fertilizer. Amounts of N from fertilizers were 100, 200, 400, or 800?mg per pot. Lettuce yield was higher for plants receiving fertilizers than with no fertilizer and increased with increased N applications, but high applications of BLO or FM suppressed yields. Nitrogen and nitrate increased in leaves as N supply increased with all fertilizers. Small changes in leaf nutrient contents other than N occurred among or with increased application of the various fertilizers. The soil carbon dioxide release and ammonia volatilization were high from fertilizers with high N concentrations. Organic fertilizers with high N increased lettuce growth at lower applications than those with low N content.     

Functional analysis of walnut polyphenol oxidase gene (JrPPO1) in transgenic tobacco plants and PPO induction in response to walnut bacterial blight

Walnut (Juglans regia) is economically important for both its wood and nut nutritional value, but it is susceptible to diseases such as walnut bacterial blight, caused by Xanthomonas arboricola pv. juglandis (Xaj). Walnuts contain many phenolic compounds, providing a good model on which to study polyphenol oxidase (PPO). We inoculated the detached walnut fruits of cultivars Ford, Chandler, Franquette, Robert Livermore, and Payne with Xaj and measured the induction of PPO activity in infected sites and adjacent to infected sites. Compared to infected and uninfected sites, PPO activity was induced significantly in areas adjacent to infected sites in all cultivars except Ford. Ford and Franquette, presenting the lowest and highest PPO activity, showed the largest and smallest mean diameter spots in response to Xaj, respectively. Polyacrylamide gel electrophoresis confirmed monophenol oxidase activity of walnut PPO in the assessed tissues. Then, we revealed the antipathogenic potential of walnut PPO through Agrobacterium tumefaciens-mediated walnut JrPPO1 gene transfer into tobacco (Nicotiana tabacum). Two transformed tobacco lines overexpressing the JrPPO1 gene were regenerated successfully and challenged with Pseudomonas syringae pv. tabaci. Transgenic lines showed significantly higher PPO activity and lower disease severity to the pathogen compared to the control. However, a significant difference in disease severity and PPO activity level was observed between the two transgenic lines. Our results demonstrate a potential defence-related role of PPO in transgenic tobacco and its induction in areas adjacent to infection sites in walnut cultivars treated with Xaj.