Purpose To determine the in vivo elastic modulus of the human cornea using vibrational optical coherence tomography (VOCT). Methods Vibrational analysis coupled with optical coherence tomography (OCT) was used to obtain the resonant frequency (RF) and elastic modulus of corneal structural components. VOCT corneal thickness values were measured using OCT images and correlated with corneal thickness determined with Pentacam (Oculus, Wetzlar, Germany). Moduli were obtained at two locations: central cornea (CC) and inferior cornea (IC). Measurements were obtained with and without anesthetic eye drops to assess their effect on the modulus measurements. Results VOCT thickness values correlated positively ( R 2 = 0.97) and linearly (y = 1.039x–16.89) with those of Pentacam. Five RF peaks (1–5) were present, although their presence was variable across eyes. The RF for peaks 1 to 5 in the CC and IC ranged from 73.5 ± 4.9 to 239 ± 3 Hz and 72.1 ± 6.3 to 238 ± 4 Hz, respectively. CC and IC moduli for peaks 1 to 5 ranged from 1.023 ± 0.104 to 6.87 ± 0.33 MPa and 0.98 ± 0.15 to 6.52 ± 0.79 MPa, respectively. Topical anesthesia did not significantly alter the modulus ( P > 0.05 for all), except for peak 2 in the CC ( P < 0.05). Conclusions This pilot study demonstrates the utility of VOCT as an in vivo, noninvasive technology to measure the elastic modulus in human corneas. The structural origin of these moduli is hypothesized based on previous reports, and further analyses are necessary for confirmation. Translational Relevance This work presents VOCT as a novel approach to assess the in vivo elastic modulus of the cornea, an indicator of corneal structural integrity and health.

The impact of heavy metals on macrobenthic invertebrates in five stations along the River Nile at Great Cairo (from Helwan to El-Qanater El-Khiria) was studied during the period from May, 2013 to February, 2014. Physico-chemical characteristics and heavy metals (iron, manganese, zinc, copper and cadmium) were analyzed in water. The highest average number (2305 org./m 2 ) of macrobenthic invertebrates was recorded during spring, while the lowest (642 org./m 2 ) was recorded during summer. Annelida, Mollusca and Arthropoda were the most dominant groups being 62 %, 34 % and 4 % respectively. Twenty two species and taxa were recorded; Mollusca (13 species) and Annelida (7 species) Arthropoda (2 species).All the heavy metal concentrations were within the permissible limits except at Helwan and Hawamdia due to the effect of discharged industrial wastes. The highest positive correlation was recorded between Arthropoda and iron & zinc, while iron recorded a negative correlation with Mollusca and Annelida. The principal component analysis (PCA) showed that the most dominant annelid Limnodrilus spp. had a positive correlation with cadmium and negative correlation with all other heavy metals. This indicates that this species can resist the high concentrations of cadmium.

In Australia, crown rot of cereals is predominantly caused by Fusarium pseudograminearum and Fusarium culmorum, and common root rot by Bipolaris sorokiniana. Fusarium graminearum is an important pathogen causing Fusarium head blight worldwide and has also been reported to cause crown rot of wheat. The comparative ability of F. pseudograminearum, F. culmorum, F. graminearum and B. sorokiniana to cause crown rot and common root rot across a range of winter cereal species requires investigation. In glasshouse trials, we inoculated one cultivar each of barley, bread wheat, durum wheat, oat and triticale with two strains of each of the four pathogens. At 21 days after inoculation, the sub-crown internode and leaf sheaths of each plant were visually rated for brown discoloration. Shoot length and dry weight of inoculated plants were compared with those of non-inoculated controls. Barley and bread wheat had the highest disease severity ratings on leaf sheaths and sub-crown internode (64.7–99.6%), whereas oat had the lowest disease severity ratings across all pathogens (&lt;5%). The shoot length of all cultivars was significantly reduced (by 12.2–55%, P &lt; 0.05) when exposed to F. pseudograminearum. This study provides a comparison of pathogenicity of crown rot and common root rot pathogens and demonstrates significant variation in visual discoloration and host response across a range of winter cereals.

No abstract

No abstract

No abstract

No abstract

No abstract