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The authors are concerned with the accuracy of azimuth and elevation estimates provided by a planar array of sensors and its relation to the array manifold differential geometry. The paper builds on previously published results regarding the influence of manifold differential geometry on the detection and resolution capabilities of linear arrays. The manifold of a planar array is introduced in terms of two families of constant-azimuth and constant-elevation curves, and their differential geometry is analysed as a function of array configuration. Circular approximation is subsequently employed to derive novel expressions for the Cramer–Rao lower bound on azimuth and elevation estimates in terms of the arc lengths and first curvatures of the respective constant-parameter manifold curves. The scenarios considered include the cases of a single emitter as well as that of two closely spaced uncorrelated emitters of arbitrary powers. The results obtained are demonstrated for the cases of two practical array configurations.

The paper is concerned with the investigation of the detection and resolution capabilities inherent to the manifold of a linear (1-dimensional) array of omnidirectional sensors, not necessarily uniform. An initial discussion, associated with the shape of the manifold of a linear array, is presented by the application of differential geometry in complex space. The shape of the manifold, which for the case of linear arrays is a hyperhelix, can be fully characterised by its length and curvatures. In this paper it is shown that the array manifold may be locally approximated by a circular arc whose radius is the inverse of the manifold's first curvature. By using the above approximation, expressions for the thresholds of resolution and detection are derived as a function of the manifold length and first curvature even for sources of unequal powers. Two laws are established: the fourth-root law which is related to the resolution problem and the square-root law which is related to the detection problem. The overall conclusion is that the thresholds predicted via differential geometry concepts represent basic performance measures for assessing and comparing the performance of different linear array geometries irrespective of the algorithm used.

The abundance and size of leaf epidermal salt hairs in Atriplex triangularis varied in response to salinity, light intensity, and aeration. Density of epidermal salt hairs decreased from the apical to the basal regions of the leaf, while the adaxial leaf surface had a lower density than the abaxial surface. The number of salt hairs per unit leaf area decreased with leaf maturation. Increase in medium salinity led to a decrease in salt hair density and an increase in bladder cell size. Reduced light intensity and lack of aeration generally caused a reduction in salt hair density. The ecological significance of epidermal salt hairs in relation to salt tolerance is discussed.

Inorganic ion and oxalate content of Atriplex triangularis organs was determined for both field- and laboratory-grown plants. Na and Cl were the principal ions accumulated by field- and laboratory-grown plants under saline conditions. Plant organs generally had an excess cation balance under all treatments. Total oxalate content was highest in plants grown in the nonsaline controls. The addition of NaCl to the media, lowering of light level, and lack of aeration decreased the total oxalate content of tissue. Leaves had the highest total oxalate concentration, averaging 12% of tissue dry weight. Field-grown plants had lower water-soluble oxalate content than did laboratory-grown plants at comparable salinity treatments.

Objective To evaluate the outcome of electrical burn on a patient's life performance and the disability induced by this type of injury. Methods This study is a prospective 6 years descriptive study. The injured patients admitted to our center between 2006 and 2008 were followed for 6 years to estimate the ability of their life and job performance after the injury. Results In the patients, 96.8% were male. The mean age of patients was 27.9 years. 73.9% of those injuries were occupational injuries. 86.5% were pure electrical injuries. 81% of patients went back to their previous job within a 5-6 year period. Only 5% had the ability to perform their usual daily activities-these patients needed financial support from family, insurance companies and government. Unfortunately 6.3% were totally disabled and needed complete help even for their minor natural needs. These patients are young and probably have a long-term life expectancy and would have a huge financial impact on the government and society. The mean length of hospital stay was 17.7 d. The mean total body surface area burned was 13.3%±11.5%. We could see an association between high voltage burns and falling down (P=0.005). High voltage burns needed longer periods away from work (197 d) in comparison with low voltage injuries (145.8 d) (P=0.003). Conclusions High voltage electrical burns are severe, needing more flap repairs and/or amputations and cause longer periods away from work.

Objective To evaluate effects of PRP injection in strengthening of repaired tendon. Methods This study was conducted in animal lab of our hospital on 20 rats. The animals were divided into two groups randomly and distal third of left Achillis tendons were cut and then repaired with Vicryl 2/0. The first group was control group and in the second group 0.5 cc of PRP was injected into the repair site. After 4 weeks all of the rats were executed and 70% of tendons were sent randomly for tensilometry and the force that required to rupture the tendons were measured. In next stage the tendons were sent for pathological exam. Results The force that was needed to rupture the tendon were not significantly different in the two groups. Neovascularization were more prevalent in PRP group but not statistically significant. There were two cases of Cartilage Metaplasia in PRP group. Conclusion It seems that using PRP has no effect on strengthening the tendons repair and may have some adverse effects. It usage needs further studies to evaluate their probable adverse side effects.

Objective: To determine the results of Bilateral Distraction Osteogenesis (DO) versus traditional methods in treatment of micrognathia. Methods: During 6 years we had 67 patients with micrognathia. In group A, randomly 35 were treated with traditional methods (Saggital osteotomy and/or bone grafts) and group B 32 cases were treated with Bilateral External Distraction Osteogenesis. Follow up was 36+/− 6 months. X-Ray, CT scan and cast modelling were done for all of the patients. SNA, SNB angles were measured in cephalograms. The patients were examined after one, two, three, six, 12 months for any complications and signs of bone resorption and relapse. Bony and soft tissue advancements were measured and compared with each other. Results: During 6 years we had 67 patients with class II malocclusion. Mean SNA angle in group A was 80.8 (80–81.5) and 80.9 (80–82) in group B. Mean SNB angle in group A was 77.6 (76.5–78) and 77.4 (76.5–78.5). After treatment mean SNB in group A was 79.1 and the difference was significant comparing to pre-op measurement (P