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We typed five microsatellite loci in 52 landraces of Italian emmer wheat to determine if genetic analysis of cereals can provide information relevant to the spread of agriculture. Each of the five loci was polymorphic with 43 allele combinations identified in the 52 landraces. The allele combinations fell into two groups. Group 1 comprised 27 genotypes found in 42 landraces and Group 2 comprised 15 genotypes found in 10 landraces. The landraces with Group 1 genotypes showed a strong correlation between geographical and genetic distances (r = 0.601, p < 0.001) but those with Group 2 genotypes did not (r = 0.116, p = 0.244). We inferred that the Group 1 landraces might therefore retain a phylogeographical structure that reflects ancient events. We present a phylogeographical model for the spread of agriculture that enables the point of origin of crop cultivation to be predicted by comparison between the genetic and geographical distances between landraces. We applied this model to the Group 1 landraces by positioning 131 hypothetical points of origin around the coastline and northern border of Italy. The highest correlation coefficients between genetic and geographical distances were seen for hypothetical points of origin located on the coast of northern Puglia. We repeated the analysis with 1040 hypothetical points of origin located within the Italian peninsula. Again, the highest correlation coefficients were located in northern Puglia. These predicted points of origin correspond with the location of the earliest agricultural sites in Italy. The results show that plant genetics can be used to study the spread of agriculture.

Background/aims: To devise and evaluate a novel Ocular Anaesthetic Scoring System (OASS) for nontopical local anaesthesia. Methods: In OASS, a score of between 0 (poor) and 14 (excellent) was devised measuring motor (ocular motility, levator and orbicularis function) and sensory functions (digital spear pressure at limbus and topical anaesthetic sting). 40 patients were studied prospectively to analyse interobserver consistency in OASS. A further 100 patients were collected into four groups receiving either sub-Tenon or peribulbar block with 150 or 300 units of hyaluronidase. Patient satisfaction was determined using the Visual Analogue Pain Scale and Iowa Satisfaction with Anaesthesia Scale. Results: There was no significant difference in OASS scores between two independent observers (p = 0.8910). The sub-Tenon approach achieved significantly better OASS scores than the peribulbar approach (p,0.0004). 300 units of hyaluronidase gave significantly higher OASS scores in both sub-Tenon (p,0.0001) and peribulbar groups (p,0.0001). Spearman rank correlation showed that OASS correlates significantly with VAPS (20.82, p,0.0001) and ISAS (0.70, p,0.0001). The median satisfaction score was significant in order of magnitude: sub-Tenon with 300 units of hyaluronidase. sub-Tenon with 150 units of hyaluronidase.peribulbar with 300 units of hyaluronidase.peribulbar with 150 units of hyaluronidase. Conclusion: OASS is a simple and robust system for assessing and comparing non-topical local anaesthetic techniques. Of the techniques evaluated, a sub-Tenon block with 300 units of hyaluronidase gives the best anaesthesia, analgesia and patient satisfaction results. Non-topical local anaesthesia is used for many ocular procedures and has a major role in cataract surgery. In the last decade the use of local anaesthesia has increased from 20% in 1991 1 to

We demonstrate the importance of graph theory for understanding boards of directors. Specifically, we focus on the ‘small world’ phenomenon. Our empirical results show that a random graph model is remarkably good at explaining board structure and connectedness in the United States, the United Kingdom and Germany. Although there are small-world traits such as ‘clustering’ and ‘short-paths’ in the corporate world, they are no more pronounced than would be expected by chance in a statistically similar, but randomly assembled corporate universe. In short, boards of directors, especially in the United States, are no more ‘clubby’ than expected. Finally, our results show the existence of positive degree correlation: directors who sit on many boards do so in the company of other directors who sit on many boards. Board members whose services are in high demand, serve on boards with similar directors.

Purpose: To introduce and describe two methods of grading the severity of infantile cataracts, and thereby propose a useful clinical guide for early surgical intervention. Methods: Thirty-three subjects, aged 1 week to 8 years, participated in the study. Twenty-two were evaluated soon after birth (1 week), and 11 in childhood (3–8 years). All had isolated infantile cataracts, of which 16 were bilateral and 17 unilateral. Nine cataract types were examined; nuclear (n ¼ 9), lamellar (n ¼ 9), posterior lenticonus (n ¼ 4), persistent hyperplastic primary vitreous (n ¼ 4), posterior polar (n ¼ 3) and single cases of total, cortical, sutural and anterior polar. Grading the infantile cataracts was performed subjectively based on the cataract morphology, density and position using an 11-point (0–10) ordinal scale. Objective measures of the cataracts were performed by scanning and then digitising photo-slit lamp images to provide cataract intensity profiles. Subjects without cataracts acted as controls. Results: Subjective gradings of 0 and 10 were assigned to the clear, cataract-free lens and the total cataract, respectively. Fixed grades of 1 (anterior polar, sutural) and 6 (posterior polar) were assigned to the three remaining cataracts with static morphologies. The five cataracts which were all progressive were given grading ranges, reflecting the initial and likely final morphological states. Objective measures were found to be valuable in indicating the exact position and relative density of the cataract, as well as accurately defining boundaries. Conclusions: The magnitude and severity of infantile cataracts can be usefully characterised by an 11-point ordinal subjective grading scale. Although subjective grading alone is satisfactory, it can be greatly assisted by objective measures, particularly in the documentation of cataract progression. Cataracts assigned grades 1–4 were considered minor obstructions to vision and therefore not candidates for early surgery. Cataracts graded 5 and above were considered major visual defects, and ideally should be removed early in life.

We describe a new approach for the real-time detection and identification of pathogens in food and environmental samples undergoing culture. Surface Enhanced Raman Scattering (SERS) nanoparticles are combined with a novel homogeneous immunoassay to allow sensitive detection of pathogens in complex samples such as stomached food without the need for wash steps or extensive sample preparation. SERS-labeled immunoassay reagents are present in the cultural enrichment vessel, and the signal is monitored real-time through the wall of the vessel while culture is ongoing. This continuous monitoring of pathogen load throughout the enrichment process enables rapid, hands-free detection of food pathogens. Furthermore, the integration of the food pathogen immunoassay directly into the enrichment vessel enables fully biocontained food safety testing, thereby significantly reducing the risk of contaminating the surrounding environment with enriched pathogens. Here, we present experimental results showing the detection of E. coli, Salmonella, or Listeria in several matrices (raw ground beef, raw ground poultry, chocolate milk, tuna salad, spinach, brie cheese, hot dogs, deli turkey, orange juice, cola, and swabs and sponges used to sample a stainless steel surface) using the SERS system and demonstrate the accuracy of the approach compared to plating results.

Models of the mechanisms of normal eye movements are typically described in terms of the block diagrams which are used in control theory. An alternative approach to understanding the mechanisms of normal eye movements involves describing the eye movement behaviour in terms of smooth changes in state variables. The latter approach captures the burst cell firing against motor error (difference between target gaze angle and current gaze angle) phase plane behaviour which is found experimentally and facilitates the modelling of variations in burst cell behaviour. A novel explanation of several types of congenital nystagmus waveforms is given in terms of a saccadic termination abnormality.

The relative involvement of different temporal frequency-selective filters underlying detection of chromatic stimuli was studied. Diverse spectral stimuli were used, namely flashed blue and yellow light spots, wide bars, and narrow bars. The stimuli were temporally modulated in luminance having constant wavelength. Although the bar-like stimuli apparently reduced the sensitivity at short and long wavelengths, the cone-opponent mechanism still remained responsible for the actual stimulus detection at different temporal frequencies. The bar-like stimuli increased sensitivity for temporal frequencies around 3-6 Hz, revealing involvement of an intermediate temporal frequency-selective filter in detection, the so-called transient-1 filter. A probability summation model for the method of adjustment was developed that assumes that detection depends on the properties of the temporal filters underlying the temporal frequency-sensitivity curve. The model supports the notion that at least two temporal frequency-selective filters are necessary to account for the shape of the sensitivity curves obtained for blue bar-like stimuli. © 2010 Optical Society of America.

In this paper we present a random graph model to explain the network structure of boards of directors. We investigate the conditions under which corporate boards can be said to be a "small-world". Our empirical results show that the random graph model is remarkably good at explaining board structure and connectedness in the United States, the United Kingdom and Germany. Although there are small-world traits such as "clustering" and "short-paths" in the corporate world, they are no more pronounced than would be expected by chance in a statistically similar, but randomly assembled corporate universe. Finally, our results show the existence of positive degree correlation: directors who sit on many boards do so in the company of other directors who sit on many boards. This result helps explain the distribution of board interlocks.

Because the oscillatory eye movements of congenital nystagmus vary from cycle to cycle, there is no clear relationship between the waveform produced and the underlying abnormality of the ocular motor system. We consider the durations of successive cycles of nystagmus which could be (1) completely determined by the lengths of the previous cycles, (2) completely independent of the lengths of the previous cycles or (3) a mixture of the two. The behaviour of a deterministic system can be characterised in terms of a collection of (unstable) oscillations, referred to as periodic orbits, which make up the system. By using a recently developed technique for identifying periodic orbits in noisy data, we find evidence for periodic orbits in nystagmus waveforms, eliminating the possibility that each cycle is independent of the previous cycles. The technique also enables us to identify the waveforms which correspond to the deterministic behaviour of the ocular motor system. These waveforms pose a challenge to our understanding of the ocular motor system because none of the current extensions to models of the normal behaviour of the ocular motor system can explain the range of identified waveforms.