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Marine biosecurity, the protection of the marine environment from impacts of non-indigenous species, has a high profile in New Zealand largely associated with a dependence on shipping. The Ministry of Fisheries is the lead agency for marine biosecurity and is tasked with managing the risks posed by pests and non-indigenous marine species. Much like the terrestrial environment, multiple pathways provide ample opportunities for new species to arrive. The Marine Biosecurity Team was established in 1998, and under the Biodiversity package delivered by government, has undertaken an ambitious programme to deliver biosecurity outcomes by reducing the knowledge gaps and establishing management frameworks. A Risk Management Framework aids decision-making and operational planning. Despite significant progress, a number of gaps have been identified in our knowledge base, capability, and capacity that require attention.

The Age-Related Eye Disease Study (AREDS) was initially conceived as a long-term multicenter, prospective study of the clinical course of age-related macular degeneration (AMD) and age-related cataract. Data on progression rates and risk factors from the study will increase understanding of the clinical course of both conditions, generate hypotheses about etiology, and aid in the design of clinical trials of potential interventions. In addition to collecting natural history data, AREDS includes a clinical trial of high-dose vitamin and mineral supplements for AMD and a clinical trial of high-dose vitamin supplements for cataract. The clinical trials were initiated largely because of the widespread public use in the United States of commercially available pharmacologic doses of vitamins and minerals to treat these two eye conditions and the absence of definitive studies on the safety and efficacy of their use. Important design issues for the clinical trials include: defining cataract and AMD, estimating event rates, determining the type and dosage of vitamins and minerals to be tested for each condition, and identifying the parameters necessary for monitoring safety and efficacy. This paper describes the AREDS design, including the study rationale and operational structure, and the approach adopted to combine, for two diseases, clinical trials with a natural history study. Control Clin Trials 1999;20:573–600

Separate studies found canola tolerant to arsenic (As) when grown in hydroponic solutions and generally sensitive to As when grown in soil. Fourteen‐day‐old canola was transferred to pots containing either soil or nutrient solution and then grown for an additional 14 days in a growth chamber at different times for the two different media. Plants were grown in 0.25‐strength Hoagland's solution containing either 0, 0.27, 6.67, or 13.3μM As or in three soils with As added at rates of 0,5, and 10 mg.kg‐1. Soil‐solution As concentrations were determined via column displacement and were the same or less (0.147 to 4.27μM) than the hydroponic As concentrations. Soil‐solution phosphorus (P) concentrations were determined in the same manner and averaged 9.28μM P compared to 500μM P from the hydroponic solutions. Chlorosis, wilting, and stunted growth—symptoms of As toxicity—occurred in canola at the highest As rate in two of the three soils used. Dry‐matter yields from the third soil were low from all trea...

Cotton-producing soils in Louisiana average 23 mg kg−1 arsenic (As) due mainly to use of As-containing agrichemicals. Bioavailability of soil As could become an important management factor if As-tolerant cotton is rotated with other more sensitive crops. The first step in modelling As bioavailability and its uptake by plants is to characterize soil supply of As. We sought to: i) determine the relationships among solution As, resin-exchangeable solid-phase As, and As addition, and ii) examine soil properties that affect these relations. Four diverse surface soils were collected from the cotton-producing areas of the state. Five rates of As from 0 to 200 mg kg−1 were applied and the soils allowed to equilibrate at 80% of “field capacity” water content for 30 days. Total initial As, As in displaced soil solution, and resin-exchangeable solid-phase As were determined for each treatment. For all soils, the concentration of solution As increased curvilinearly with As addition, conforming to the equation Assol=axc+d. Values of “c” describing the curvilinearity ranged from 1.09 to 3.19. Curvilinearity was negatively related to both initial solution As and diethylenetriaminepentaacetic acid (DTPA)-extractable manganese (Mn) (r2=0.99). DTPA-extractable Mn complexed As from the solution phase. The concentration of resin-exchangeable solid-phase As increased at a decreasing rate with As addition. The relation was described by the equation Asresp=mxl+n, where values for the curvilinearity, l, ranged from 0.048 to 0.986. Concentrations approached a point where the adsorption sites for this phase became saturated and any additional As remained in solution. These relationships provide valuable information for modelling As uptake by plant roots.

Soil volumetric water contents, φ, at −33 kPa potential may vary with soil from 0.06 to 0.70. Because P diffusion depends on φ, most economic P fertilizer rates required for different soils may require adjusting according to their soil-water relationships. The objective of this study was, after experimentally verifying a mechanistic nutrient uptake model on a series of soils varying in θ at −33 kPa potential, to use the model to predict labile P levels needed for each of these soils to achieve equal P uptake by maize (Zae mays L.) and verify these predictions. Maize was grown in a pot experiment using four soils having θ of 0.13, 0.20, 0.26, and 0.40 at −33 kPa each at 0, 200, and 400 mg kg-1 of added P. When root parameters obtained experimentally were used, predicted P uptake with the uptake model agreed with observed P uptake, y=0.99x+9.08 (r2=0.98). When P uptake was plotted vs. soil solution P, Cli, the relation varied with soil. The higher the θ the lower the Cli needed for equal P uptake. A similar relation was found between P uptake and diffusible soil P, Csi. Differences between the two plots occurred because of differences among soils in buffer power, ΔCsi/ΔCli. The Csi vs. P added relation was used to calculate differences among soils in the Csi needed to obtain equal P uptake. The Csi values ranged from 1.3 to 4.0 mmol kg−1. The calculated values were used in a second pot experiments to verify the predictions. No significant difference (α=0.05) in P uptake occurred. The results of this research indicate that the mechanistic nutrient uptake model can be used to predict the degree of adjustments in Csi needed to obtain the most economic P fertilizer rates among soils varying in θ.

Experimental and observational data suggest that micronutrients with antioxidant capabilities may retard the development of age-related cataract.To evaluate the effect of a high-dose antioxidant formulation on the development and progression of age-related lens opacities and visual acuity loss.The 11-center Age-Related Eye Disease Study (AREDS) was a double-masked clinical trial. Participants were randomly assigned to receive daily oral tablets containing either antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg) or no antioxidants. Participants with more than a few small drusen were also randomly assigned to receive tablets with or without zinc (80 mg of zinc as zinc oxide) and copper (2 mg of copper as cupric oxide) as part of the age-related macular degeneration trial. Baseline and annual (starting at year 2) lens photographs were graded at a reading center for the severity of lens opacities using the AREDS cataract grading scale.Primary outcomes were (1) an increase from baseline in nuclear, cortical, or posterior subcapsular opacity grades or cataract surgery, and (2) at least moderate visual acuity loss from baseline (/=15 letters). Primary analyses used repeated-measures logistic regression with a statistical significance level of P =.01. Serum level measurements, medical histories, and mortality rates were used for safety monitoring.Of 4757 participants enrolled, 4629 who were aged from 55 to 80 years had at least 1 natural lens present and were followed up for an average of 6.3 years. No statistically significant effect of the antioxidant formulation was seen on the development or progression of age-related lens opacities (odds ratio = 0.97, P =.55). There was also no statistically significant effect of treatment in reducing the risk of progression for any of the 3 lens opacity types or for cataract surgery. For the 1117 participants with no age-related macular degeneration at baseline, no statistically significant difference was noted between treatment groups for at least moderate visual acuity loss. No statistically significant serious adverse effect was associated with treatment.Use of a high-dose formulation of vitamin C, vitamin E, and beta carotene in a relatively well-nourished older adult cohort had no apparent effect on the 7-year risk of development or progression of age-related lens opacities or visual acuity loss.

To describe the results of retinal tears and rhegmatogenous retinal detachments (RD) in adults with retinopathy of prematurity (ROP).Noncomparitive interventional case series.Retrospective cohort of 216 eyes of 108 patients, 15 years or older, followed for up to 23 years (median, 6.2 years).One eye was initially seen with an RD, and during follow-up 30 eyes had an RD develop. An additional surgical procedure was required in 7 of the 31 eyes (23%) with an RD. Four eyes were initially seen with retinal tears, and during follow-up 19 eyes had a retinal tear develop. Seven of the 23 eyes (30%) with a retinal tear had initial repair fail. Eyes with minimal cicatricial changes from ROP were still at high risk for tears and detachments developing. Eighty percent of eyes with retinal tears and 60% of eyes with an RD that started with vision20/60 maintained that level of vision at the final examination.In patients with a history of premature birth, features of fundus examinations do not correlate with the occurrence of a retinal tear or RD. Repair of a tear or detachment in such a patient is more likely to require multiple procedures but can still be associated with good visual results. Physicians should consider widespread relief of vitreoretinal traction for a tear or detachment in any patient with a history of premature birth.

Soil samples were collected on a 0.4-ha (1.0-ac) grid from two agricultural fields in northeastern Mississippi. The samples were measured with a spectrophotometer for diffuse reflectance between 250 and 2500 nm. Remote-sensing and topographic data of the fields were also collected. The objective was to determine whether remote-sensing data, along with other easily obtainable data like topography, could be used to predict the reflectance spectra of soils from small sample sites in agricultural fields. From the raw reflectance spectra, 50-nm-band averages were calculated. Significant correlations existed between laboratory soil-reflectance spectra and models comprised of remote-sensing and topographic data. The highest coefficient of determination was around 0.5. Inclusion of an extra multispectral image improved the correlation between selected models and spectral variables. Coarser resolutions of remote-sensing data appeared to be better than finer resolutions at predicting the laboratory reflectance spectra of soil samples. Site-specific field elevation data added some information to predictions. Remote-sensing bands were predictive of spectral variables in the same spectral region.

Soil samples were collected on a 0.4–ha (1.0–ac) grid from two agricultural fields in northeastern Mississippi. The samples were measured for soil nutrient composition, soil texture, and diffuse reflectance between 250 and 2500 nm. The data were examined for two purposes: (1) to understand the relationships between soil properties and reflectance spectra, and (2) to understand the sources of variability in the reflectance spectra. From the raw reflectance spectra, 50–nm–band averages were calculated. There were significant correlations between groups of the averaged spectra and soil properties, but no single 50–nm band was highly correlated to any soil property. Soil nutrients were better correlated with spectra in one field, but texture was better correlated with spectra in the other. Only Ca and Mg in one field and clay and pH in the other had multiple–regressor model correlations with R 2 values greater than 0.50. The relationships between soil properties and reflectance spectra were not consistent between fields. Based on the study of variability in reflectance spectra, the results of which were significantly dependent on the instrument used in this study, it was found that certain sections of the spectrum are more useful for discriminating among soil samples with differing characteristics. Spectral regions of high discriminatory power were 400 to 800 nm and 950 to 1500 nm.

To report a newly defined complication of foldable intraocular lenses (IOLs), namely silicone oil-silicone IOL interaction. This is a complication not generally seen by the implanting cataract surgeon but, rather, at a later stage in a patient's postoperative course, by a vitreoretinal surgeon.Three clinical case histories, including two explanted silicone IOLs, were submitted for analysis. The submitted silicone lenses were photographed under water, and the nature of the silicone oil coating was documented.In each instance, the silicone coating was manifest as a thick coating with droplet formation on the lens surface that was tenaciously adherent and could not be dislodged by instruments or injection of viscoelastics.The use of silicone IOLs in patients with current vitreoretinal disease or those who are at high risk for future vitreoretinal disease that may require silicone oil as part of the therapy should be reconsidered. The authors recommend that information regarding the existence and significance of this complication be printed on all silicone oil and silicone IOL packages and inserts (if not as a warning, at least as an informative comment regarding the existence of this condition). This is a rare but clinically significant complication that will affect the occasional patient treated with both of these modalities.

The prevalence of postoperative macular pucker and the factors associated with its development after successful surgery for proliferative vitreoretinopathy (PVR) using silicone oil or gas tamponade are unknown.The postoperative status of the macula was determined by reviewing the photographs of 336 eyes taken 6 months after randomization. Two hundred eleven eyes with attached maculas were identified and analyzed to determine the prevalence of macular pucker after silicone oil and gas tamponades in eyes without (group 1) and with (group 2) previous vitrectomy surgery. Data obtained at baseline, from the primary study surgery, and from subsequent examinations and repeat surgeries during a follow-up period of 6 months were analyzed for factors associated with postoperative macular pucker.The 6-month-point prevalence rate of postoperative macular pucker was 15% (32 of 211 eyes). Ten of the 32 eyes were new cases of macular pucker. The authors were unable to document a difference in the 6-month-point prevalence of postoperative macular pucker between group 1 and group 2 eyes (13% versus 18%) or between eyes randomized to gas versus silicone oil (19% versus 12%). Postoperative pucker was three times as likely to develop in aphakic/pseudophakic eyes compared with phakic eyes (P = 0.02). Focal contraction posteriorly causing starfolds, and intravitreal contraction involving the vitreous base or vitreous cavity, were significantly less prevalent in eyes with postoperative macular pucker (P0.05). Large (or = 2 disc diameters) retinal breaks (P = 0.04) were associated significantly with postoperative macular pucker (P = 0.04). The authors were unable to document an association between postoperative macular pucker and the type of adhesive modality used or the extent of its application. Postoperative visual acuity was significantly better if the macula was not puckered (P0.01).The occurrence of macular pucker after successful surgery for retinal detachments complicated by severe PVR is not influenced by the choice of intraocular tamponade. Certain preoperative factors may be associated with postoperative macular pucker.

To evaluate the reproducibility of a modified Burke-type diet history within the context of a long-term, randomized, 29-center clinical diabetes study.Diet histories were collected by trained interviewers at the end of years 1 and 2 after subjects were randomly assigned to the intensive treatment group or the conventional treatment group. Mean daily intakes of energy, protein, carbohydrate, total fat, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, cholesterol, and dietary fiber were calculated for each treatment group at each time period.The study population consisted of 139 subjects in the intensive treatment group and 128 subjects in the conventional treatment group. Ages ranged from 13 to 39 years; groups included men and women. Distribution by age, sex, race, proportion of smokers, weight reported as percent ideal body weight, and duration of IDDM were similar in both groups.Differences in nutrient intake between the conventional and intensive treatment groups at each time period were tested for significance using the Wilcoxon rank-sum test. The Wilcoxon paired differences test was used to assess changes between time periods within treatment groups. Linear agreement between repeated administrations of the diet history was evaluated using Pearson's correlation coefficient, and the extent of within-subject reproducibility was assessed by intraclass correlation.No statistically significant differences in energy and nutrient intakes were observed between the two groups at either year 1 or year 2. Within each treatment group, energy and nutrient intake differences between times were not statistically significant. Correlation coefficients between years 1 and 2 ranged from .51 for dietary fiber to .72 for dietary cholesterol; within-subject reproducibility was slightly higher.These results demonstrate long-term reproducibility for the meal-based diet history in the DCCT population.

Due to the difficulties encountered in positioning severely neurologically impaired individuals for videofluoroscopic studies, the Rehab Tech Video FluoroChair was developed. The purpose of the chair is to provide the severely disabled patient with safe, stable postural support in an upright position for videofluoroscopic studies, with anterior-posterior, lateral, and rotational views easily performed. The chair features a removable headrest, a full back support, armrests, lateral truncal supports, and a patented base which is clamped to the footboard of the radiology table and allows for 200 degrees rotation of the patient. Two case studies illustrate the practical use and versatility of the Rehab Tech Video FluoroChair.

Managing the insulin-requiring diabetic patient in an ambulatory setting includes metabolic regulation of the diabetes and education in its self-care. Means of achieving these goals include structured group or one-on-one individualized sessions. Third party policies relating to ambulatory care are challenged and their need for fiscal support emphasized. During the coming decade, diabetic patients should 1) have access to ambulatory care programs for metabolic regulation and education in self-care, 2) expect third party support of these programs, and 3) heighten their own priorities on diabetes care to ensure quality management of their diabetes.

Observational and experimental data suggest that antioxidant and/or zinc supplements may delay progression of age-related macular degeneration (AMD) and vision loss.To evaluate the effect of high-dose vitamins C and E, beta carotene, and zinc supplements on AMD progression and visual acuity.The Age-Related Eye Disease Study, an 11-center double-masked clinical trial, enrolled participants in an AMD trial if they had extensive small drusen, intermediate drusen, large drusen, noncentral geographic atrophy, or pigment abnormalities in 1 or both eyes, or advanced AMD or vision loss due to AMD in 1 eye. At least 1 eye had best-corrected visual acuity of 20/32 or better. Participants were randomly assigned to receive daily oral tablets containing: (1) antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg); (2) zinc, 80 mg, as zinc oxide and copper, 2 mg, as cupric oxide; (3) antioxidants plus zinc; or (4) placebo.(1) Photographic assessment of progression to or treatment for advanced AMD and (2) at least moderate visual acuity loss from baseline (or =15 letters). Primary analyses used repeated-measures logistic regression with a significance level of.01, unadjusted for covariates. Serum level measurements, medical histories, and mortality rates were used for safety monitoring.Average follow-up of the 3640 enrolled study participants, aged 55-80 years, was 6.3 years, with 2.4% lost to follow-up. Comparison with placebo demonstrated a statistically significant odds reduction for the development of advanced AMD with antioxidants plus zinc (odds ratio [OR], 0.72; 99% confidence interval [CI], 0.52-0.98). The ORs for zinc alone and antioxidants alone are 0.75 (99% CI, 0.55-1.03) and 0.80 (99% CI, 0.59-1.09), respectively. Participants with extensive small drusen, nonextensive intermediate size drusen, or pigment abnormalities had only a 1.3% 5-year probability of progression to advanced AMD. Odds reduction estimates increased when these 1063 participants were excluded (antioxidants plus zinc: OR, 0.66; 99% CI, 0.47-0.91; zinc: OR, 0.71; 99% CI, 0.52-0.99; antioxidants: OR, 0.76; 99% CI, 0.55-1.05). Both zinc and antioxidants plus zinc significantly reduced the odds of developing advanced AMD in this higher-risk group. The only statistically significant reduction in rates of at least moderate visual acuity loss occurred in persons assigned to receive antioxidants plus zinc (OR, 0.73; 99% CI, 0.54-0.99). No statistically significant serious adverse effect was associated with any of the formulations.Persons older than 55 years should have dilated eye examinations to determine their risk of developing advanced AMD. Those with extensive intermediate size drusen, at least 1 large druse, noncentral geographic atrophy in 1 or both eyes, or advanced AMD or vision loss due to AMD in 1 eye, and without contraindications such as smoking, should consider taking a supplement of antioxidants plus zinc such as that used in this study.

The causal relationship between trauma and retinal detachment is frequently uncertain because two separate etiologic factors are involved: the traumatic insult and the preexisting state of vitreoretinal degeneration. The relative influence of each factor depends upon its severity. The purpose of this paper is to describe the clinical characteristics of retinal detachments caused by severe contusion in eyes selected so as to minimize the influence of vitreoretinal degeneration. These characteristics are compared to those of nontraumatic cases as previously reported by Schepens and Marden.1,2 Materials and Methods One hundred and sixty patients with retinal detachment due to ocular contusion were selected from the records of the Retina Associates and the Retina Service of the Massachusetts Eye and Ear Infirmary according to the following criteria: Unilateral retinal detachment preceded by ocular contusion. Objective signs of contusion in the affected eye. Absence of visible vitreoretinal degeneration of the types known to

Ten eyes which had developed retinitis proliferans following branch retinal vein occlusion were treated with xenon photocoagulation utilizing an ablative technique limited to the effected retinal quadrants. In eight of the ten eyes, complete regression of the vessels was obtained, as evidenced by nonfilling on subsequent fluorescein angiography. The remaining two eyes showed significant but incomplete closure. There were no postoperative vitreous hemorrhages, no significant permanent complications, and the visual acuity remained at or better than pretreatment levels in all cases. In conclusion, we wish to reemphasize the limited scope of this report. The series, though consecutive, is small and the follow-up period relatively short. On the basis of the cases presented here, we believe that continued investigation using this mode of treatment is warranted, and that this method may prove to be of significant value in the management of complicated retinal branch vein occlusion.