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The primary objective of this study was to assess whether the topical administration of two neuroprotective drugs (brimonidine and somatostatin) could prevent or arrest retinal neurodysfunction in patients with type 2 diabetes. For this purpose, adults aged between 45 and 75 years with a diabetes duration ≥5 years and an Early Treatment of Diabetic Retinopathy Study (ETDRS) level of ≤35 were randomly assigned to one of three arms: placebo, somatostatin, or brimonidine. The primary outcome was the change in implicit time (IT) assessed by multifocal electroretinography between baseline and at the end of follow-up (96 weeks). There were 449 eligible patients allocated to brimonidine (n = 152), somatostatin (n = 145), or placebo (n = 152). When the primary end point was evaluated in the whole population, we did not find any neuroprotective effect of brimonidine or somatostatin. However, in the subset of patients (34.7%) with preexisting retinal neurodysfunction, IT worsened in the placebo group (P < 0.001) but remained unchanged in the brimonidine and somatostatin groups. In conclusion, the topical administration of the selected neuroprotective agents appears useful in preventing the worsening of preexisting retinal neurodysfunction. This finding points to screening retinal neurodysfunction as a critical issue to identify a subset of patients in whom neuroprotective treatment might be of benefit.

Hintergrund: Zunehmend werden anti-VEGF Substanzen bei proliferativer diabetischer Retinopathie (PDR) eingesetzt. Jedoch ist unklar, wie lange der Effekt anhält und wie engmaschig Patienten kontrolliert werden sollen. Methoden: 106 Patienten mit PDR ohne Diabetisches Makulaödem (DMÖ)[zum vollständigen Text gelangen Sie über die oben angegebene URL], 31. Jahrestagung der Retinologischen Gesellschaft

The article focuses on the problem of 2-D (two-dimensional) DOA (Direction of Arrival) estimation of a single source in the scenario of far-field using a single vector hydrophone which comprises three orthogonal velocity-sensors plus one spatially co-located pressure sensor. In this proposed approach, a temporal invariance is formed via two time-delayed data sets collected from a vector hydrophone, and the ESPRIT (Estimation of Signal Parameters via Rotational Invariance Techniques) is utilized to estimate the DOA. A sliding method is proposed to process data collected by a single vector hydrophone in a period of time so that the motion trajectory of the target can be determined. Both the theoretical analysis and the results of computer simulation demonstrate that the algorithm is an effective 2-D DOA estimation approach.

In this paper, an improved joint processing algorithm based on Estimation of Signal Parameters via Rotational Invariance Technique(ESPRIT), which can efficiently combine acoustic pressure and analytic velocity, is proposed to estimate azimuth angle. This method can be applied in acoustic vector sensor array (AVSA) of any formation. A novel cross-covariance matrix of acoustic pressure and analytic velocity is constructed and the ESPRIT algorithm based on total-least-squares (TLS) criterion is used to determine the azimuth angle of incident signals in a background noise. By using the coherency between acoustic pressure and particle velocity, this algorithm could suppress interference well in isotropic noise field. Simulations show that the proposed algorithm is more efficient than existing algorithms especially in low-SNR environment.

This dual-ducted SUAV is a nonlinear and strong coupling of multiple-input and multiple-output system, and particularly between the pitch and roll channels channel coupling is strong, in order to implement effective control, it must be decoupled. The traditional methods are difficult to achieve effective control of the strong coupling of multivariable systems. Neural network which has a strong learning ability, is able to learn from the sample and can adapt to changing learning condition. Thus, the neural network can be used to simulate the learning process of operator, and operating characteristics information of objects can be excavated from the measured data, and accordingly change the parameters of the controller and decoupling network. This paper presents a attitude control algorithm of the dual-ducted SUAV which combine ADRC algorithms with neural network decoupling control algorithm, to design a SUAV decoupling controller. The simulation results showed that the attitude control channels between the pitch and roll were independently of each other, indicating a good solution to decouple the coupling between the pitch and roll channels based on neural network algorithm.

This dual-ducted SUAV is a nonlinear and strong coupling of multiple-input and multiple-output system, and particularly between the pitch and roll channels channel coupling is strong, in order to implement effective control, it must be decoupled. The traditional methods are difficult to achieve effective control of the strong coupling of multivariable systems. For the SUAV model of nonlinear coupling characteristics, based on the establishment of the UAV attitude model, this paper designed an attitude ADRC decoupling controller. The simulation showed this ADRC decoupling controller had strong robustness and immunity, and solved the channels coupling between the pitch and roll.

Recently, the SUAV has become the research focus at home and abroad. There is a new aircraft type: double ducted tilting Subminiature UAV system, this paper put forward a new attitude navigation system:AHRS-based low-cost GPS carrier phase orientation Navigation System. AHRS aids GPS fastly fix the attitude.This article proposed application the constraint solving the ambiguity basic model, which is based on the double differential equations of the carrier phase measurement. Then we use baseline length and the inaccurate attitude angle constraint to solver integer ambiguity. By the static experimental results show that this method is fast, effective, the AHRS-GPS system can provide high accuracy navigation for SUAV.

Since Small Unmanned Helicopter flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

Based on the sub-mini dual ducted UAV dynamics analysis of Newton, and according to the characteristics of the hovering and variable posture mechanism, this paper combined methods of mechanism analysis with system identification to get the attitude model of under actuated sub-mini dual ducted UAV, which contained input variable, output variable and some unknown parameters. Then the subspace method used the real flying data to identify above the attitude model. Finally，the correctness of the identification model was verified.

Recently, the UAV has become the research focus at home and abroad. this paper puts forward a unconventional type: double ducted tilting Subminiature UAV system (SUAV) , and carries out the research of the control system for this SUAV. Since SUAV flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

For heterogeneous oilfields, the permeability of formations vary from a few milli darcies to hundreds or even thousands of milli darcies. In order to solve this problem, to improve the injection profile, for the low permeability reservoir is broken down, it is necessary to study the temporary plugging steering acidizing technique. Using laboratory experiments, the research and development of temporary plugging agent, Auxiliary reagents selection, at last, through indoor core simulation experiment to form the system of temporary plugging acidizing formula, so as to achieve temporary plugging technology, not only solve the difficulties of heterogeneous oil field, but also save the cost, improve the economic benefit.

PURPOSE In age-related macular degeneration (ARMD) angiomatous proliferation can progress from the retina into the subretinal space. Retinal angiomatous proliferation (RAP) can be diagnosed by angiographic findings and optical coherence tomography (OCT). We investigated the outcome of photodynamic therapy in patients with RAP. METHODS 14 patients with ARMD and RAP were retrospectively analysed using a standardised protocol. The protocol included best corrected visual acuity (BCVA), ophthalmoscopy, OCT examination, fundus photography and fluorescein angiography (FAG). In a masked fashion the OCT and angiographic findings were independently graded in 3 stages (RAP I: intraretinal neovascularisation, RAP II: subretinal neovascularisation with a retinal-retinal anastomosis or subretinal neovascularisation with a serous pigment epithelial detachment, RAP III: choroidal neovascularisation with vascularised pigment epithelial detachment and retinal-choroidal anastomosis). 15 eyes of these 14 patients were evaluated pre- and post-PDT with the standardised protocol and the data statistically analysed. RESULTS The age ranged from 58 to 90 years (median 76 years). In 15 eyes of 14 patients with RAP a PDT was performed. 6 of these 15 PDT cases were successfully treated and gained >or= 2 lines (dry macula), 3 eyes with RAP I and 3 with RAP II. 4 eyes stablilised with +/-1 line (persistent macular oedema) under PDT with 2 RAP I, 1 RAP II and 1 RAP III. 5 eyes showed a deterioration with loss of >or= 2 lines (increasing macula oedema) with 2 RAP I and 3 RAP III. The median BCVA was pre-PDT in the successful cases 0.3, post-PDT 0.6, in the stable cases pre-PDT 0.2, post-PDT 0.2 and in the deterioration group pre-PDT 0.4 and post-PDT 0.01. CONCLUSIONS According to our study PDT might be helpful in the treatment of RAP stages I and II in selected cases in ARMD patients. Further prospective studies are required to investigate the outcome of PDT in RAP.

Objective: To demonstrate superiority of ranibizumab 0.5 mg monotherapy or combined with laser over laser alone based on mean average change in best-corrected visual acuity (BCVA) over 12 months in diabetic macular edema (DME). Design: A 12-month, randomized, double-masked, multicenter, laser-controlled phase III study. Participants: We included 345 patients aged >= 18 years, with type 1 or 2 diabetes mellitus and visual impairment due to DME. Methods: Patients were randomized to ranibizumab + sham laser (n = 116), ranibizumab + laser (n = 118), or sham injections + laser (n = 111). Ranibizumab/sham was given for 3 months then pro re nata (PRN); laser/sham laser was given at baseline then PRN (patients had scheduled monthly visits). Main Outcome Measures: Mean average change in BCVA from baseline to month 1 through 12 and safety. Results: Ranibizumab alone and combined with laser were superior to laser monotherapy in improving mean average change in BCVA letter score from baseline to month 1 through 12 (+6.1 and +5.9 vs +0.8; both P= 15 and BCVA letter score level >73 (20/40 Snellen equivalent) with ranibizumab (22.6% and 53%, respectively) and ranibizumab + laser (22.9% and 44.9%) versus laser (8.2% and 23.6%). The mean central retinal thickness was significantly reduced from baseline with ranibizumab (-118.7 mu m) and ranibizumab + laser (-128.3 mu m) versus laser (-61.3 mu m; both P

Physical and toxicological aspects of different perfluorocarbons and semifluorinated compounds are discussed. The urgent need for ultrapurification of perfluorocarbons is demonstrated. In vitro laser treatment simulating physiological conditions of two ultrapurified perfluorocarbons used for temporary tamponade and mechanical fixation of unfolded retina in case of giant tears, and one semifluorinated diether resulted in no detectable chemical alteration. Cytotoxic examinations of both laser treated and untreated probes showed no difference in cell proliferation.

We report on a 22-year-old white female with bilateral Leber's stellate neuroretinitis occurring 5 weeks after a viral-like illness. Serological tests revealed a seroconversion for Borrelia burgdorferi indicating an etiological connection. During therapy with 200 mg doxycycline daily for 2 weeks on systemically steroids the optic disc swelling and macular star figure resolved. Visual acuity improved from 0.4 to 1.0 in this time period. It is important that the ophthalmologist should consider Lyme-Borreliosis in isolated neuroretinitis, because the prognosis depends on the time when treatment is initiated.

Ischemic ophthalmopathy is the leading ocular symptom of occlusive processes of the internal carotid artery. It can be preceded by embolic symptoms as amaurosis fugax or occlusion of a branch or the main stem of the central retinal artery. Both, ophthalmologists and neurologists, should be familiar with these disturbances as they can involve important diagnostic and therapeutic consequences. Five out of six patients with an angiographically demonstrated extracranial occlusion of one internal carotid artery and a retrograde collateral circulation to the intracranial space via the external carotid and the ophthalmic arteries showed an ischemic ophthalmopathy of the ipsilateral eye. This high coincidence supports the notion that an ischemic ophthalmopathy may not be the result of the occlusive process of the internal carotid artery per se, but may be caused by ocular "steal mechanisms" due to the retrograde orbital collateral circulation.