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2022 ◽  
Vol 8 ◽  
Author(s):  
Xue Bai ◽  
Rui Hua

Vogt-Koyanagi-Harada disease (VKH) is a rare multisystemic inflammatory autoimmune disorder. Glaucoma secondary to VKH frequently occurs during the recurrent phase of anterior uveitis; however, acute angle-closure glaucoma (ACG) secondary to both VKH and human immunodeficiency virus (HIV) infection has rarely been reported. We describe a case of secondary acute ACG involving VKH, characterized by sudden vision loss, moderately elevated intraocular pressure (IOP), shallow anterior chamber, and fully or partially closed angle, in an HIV-infected patient. Both VKH and HIV infection contributed to the occurrence of ACG due to the leakage and forward rotation of the ciliary body, as well as choroidal effusion. The deterioration of IOP and serous macular detachment were observed after initial corticosteroid therapy. Visual acuity and IOP were improved with subretinal fluid absorption after continued corticosteroid therapy. Understanding the response of IOP and serous macular detachment after corticosteroid therapy is important for clinical practice.


2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Weiwei Wang ◽  
Xin Yang ◽  
Qian Yao ◽  
Qianqian Xu ◽  
Wenting Liu ◽  
...  

Abstract Background To investigate characteristics of the acute angle-closure crisis (AACC) and fellow eyes using confocal microscopy. Methods Unilateral AACC patients hospitalized at the Xi’an People’s Hospital from October 2017 to October 2020 were recruited in this cross-sectional study. Age-matched participants scheduled for cataract surgery were enrolled as a healthy control group. Corneal epithelial cells, subepithelial nerve fiber plexus, stromal cells, and endothelial cells were examined by confocal and specular microscopy. Results This study enrolled 41 unilateral AACC patients (82 eyes) and 20 healthy controls (40 eyes). Confocal microscopy revealed that the corneal nerve fiber density, corneal nerve branch density and corneal nerve fiber length were reduced significantly in AACC eyes. The stromal cells were swollen and the size of the endothelial cells was uneven with the deposition of punctate high-reflective keratic precipitate on the surface. In severe cases, the cell volume was enlarged, deformed, and fused. The corneal subepithelial nerve fiber, stromal layer, and endothelial layer were unremarkable in the fellow eyes, and the density of the endothelial cells was 2601 ± 529 cells/mm2, which was higher than 1654 ± 999 cells/mm2 in AACC eyes (P < 0.001). Corneal edema prevented the examination of 17 eyes using specular microscopy and in only four eyes using confocal microscopy. There were no significant differences in endothelial cell density between confocal and specular microscopy in the AACC eyes (P = 0.674) and fellow eyes (P = 0.247). The hexagonal cell ratio reduced significantly (P < 0.001), and average cell size and coefficient of variation of the endothelial cells increased significantly compared with fellow eyes (P < 0.001, P = 0.008). Conclusions AACC eye showed decreased density and length of corneal subepithelial nerve fiber plexus, activation of stromal cells, increased endothelial cell polymorphism, and decreased density.


Actuators ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 22
Author(s):  
Liang Wang ◽  
Zhiqiang Zhai ◽  
Zhongxiang Zhu ◽  
Enrong Mao

To improve the path tracking accuracy of autonomous tractors in operation, an improved Stanley controller (IMP-ST) is proposed in this paper. The controller was applied to a two-wheel tractor dynamics model. The parameters of the IMP-ST were optimized by multiple-population genetic algorithm (MPGA) to obtain better tracking performance. The main purpose of this paper is to implement path tracking control on an autonomous tractor. Thus, it is significant to study this field because of smart agricultural development. According to the turning strategy of tractors in field operations, five working routes for tractors were designed, including straight, U, Ω, acute-angle and obtuse-angle routes. Simulation tests were conducted to verify the effectiveness of the proposed IMP-ST in tractor path tracking for all routes. The lateral root-mean-square (RMS) error of the IMP-ST was reduced by up to 36.84% and 48.61% compared to the extended Stanley controller and the original Stanley controller, respectively. The simulation results indicate that the IMP-ST performed well in guiding the tractor to follow all planned working routes. In particular, for the U and Ω routes, the two most common turning methods in tractor field operations, the path tracking performance of the IMP-ST was improved by 41.72% and 48.61% compared to the ST, respectively. Comparing and analyzing the e-Ψ and β-γ phase plane of the three controllers, the results indicate that the IMP-ST has the best control stability.


2022 ◽  
Author(s):  
Jonathan J Cho ◽  
Samantha D Fabrizio ◽  
Ariana K Tabing ◽  
Gilbert E Boswell ◽  
Gregory J Condos

ABSTRACT Anomalous aortic origin of a coronary artery (AAOCA) is a rare congenital abnormality associated with myocardial ischemia and sudden cardiac death. We present a case of a 20 year old previously healthy male presenting with exertional syncope and non-ST elevation myocardial infarction. Coronary computed tomography angiography showed an anomalous left main coronary artery arising from the right coronary cusp with a slit-like appearance, acute angle origin, intramural course, and a subsequent inter-arterial course between the main pulmonary artery and the proximal aorta. Cardiac magnetic resonance imaging demonstrated myocardial infarction in the distribution of the left main coronary artery. The patient underwent successful surgical correction with unroofing of the left main coronary artery. He has had no syncopal episodes or recurrence of chest pain and returned to full duty status in the United States Marine Corps. This case report demonstrates the evaluation and management of a patient with AAOCA.


Author(s):  
Jia Wang ◽  
Ming Zeng ◽  
Xiaoning Wang ◽  
Dazhang Li ◽  
Jie Gao

Abstract We propose to use a frequency doubled pulse colliding with the driving pulse at an acute angle to trigger ionization injection in a laser wakefield accelerator. This scheme effectively reduces the duration that injection occurs, thus high injection quality is obtained. Three-dimensional particle-in-cell simulations show that electron beams with energy of ~500 MeV, charge of ~40 pC, energy spread of ~1% and normalized emittance of a few millimeter milliradian can be produced by ~100 TW laser pulses. By adjusting the angle between the two pulses, the intensity of the trigger pulse and the gas dope ratio, the charge and energy spread of the electron beam can be controlled.


2022 ◽  
Vol 14 (4) ◽  
pp. 172-178
Author(s):  
A. A. Panov ◽  
A. A. Petukhova ◽  
Ya. V. Malygin ◽  
B. D. Tsygankov ◽  
M. A. Kazanfarova

Antipsychotics are widely used in psychiatric practice for treating schizophrenia, bipolar disorder, and other diseases, including those treated off-label. They manifest many adverse effects, including ophthalmic ones. Some of these effects, such as persistent mydriasis, cycloplegia, extraocular muscle dystonia, and visual hypersensitivity attacks are reversible, since they disappear after dose reduction or drug withdrawal. Yet other side effects, such as cataracts, corneal edema, acute angle closure glaucoma and retinopathy are threatening for sight and may lead to permanent visual acuity decline and even blindness. The review provides data on the incidence of ocular side effects (both typical and atypical) of multiple antipsychotics, their clinical manifestations, pathogenesis and treatment. Eye examination is recommended for patients taking antipsychotics in the early periods of treatment and then twice a year. The psychiatrists need to know about the adverse effects of individual drugs whilst the ophthalmologists should be aware of their semiotics, pathogenesis and treatment, since timely diagnosis and treatment of pathological changes, together with antipsychotic therapy modification, prevent the development of severe and irreversible visual impairment in the majority of cases.


2022 ◽  
Vol 12 (1) ◽  
pp. 139-145
Author(s):  
Jianlian Guo ◽  
Qiang Dong ◽  
Min Liu

To explore the effect of phacoemulsification along with intraocular lens (IOL) implantation on the treatment of primary angle closure glaucoma (PACG), a total of 50 patients (54 eyes) with PCG who had undergone surgery were selected as the research objects, in which, there were 16 eyes with the acute PACG in pre-clinical stage, 20 eyes with acute PACG during acute attack, and 18 eyes with chronic PACG, and all patients received phacoemulsification along with IOL implantation therapy. The patient’s best corrected visual acuity, anterior chamber (AC), anterior depth, intraocular pressure (IOP), visual field, and fundus conditions were measured during the operation, after the operation, and during the follow-up period. The postoperative visual acuity of the patients with three types of PACG was greatly corrected, in which 30 eyes had corrected visual acuity above 0.5, and there were statistically significant differences (SSDs) (P < 0.05); angle closure of 54 eyes had different degrees of improvement, the opening degree of the acute angle closure is better than that of the chronic angle closure, and there were SSDs (P < 0.05); each of 54 eyes showed different degrees of deepening in the central AC, and there were SSDs (P < 0.05); postoperative IOP decreased greatly in all 54 eyes, and there were SSDs (P < 0.05). In conclusion, the IOL implantation based on phacoemulsification can effectively treat the PACG, at the same time reduce IOP, promote angle opening, enhance vision field of the patients, and ultimately achieve the purpose of improving surgical success.


2022 ◽  
Vol 100 (S267) ◽  
Author(s):  
Safa Ben Aoun ◽  
Meriem Ouederni ◽  
Fehmy Nefaa ◽  
Wijdene Nabi ◽  
Monia Cheour

Author(s):  
Ji Won Bak ◽  
Yeonji Noh ◽  
Juyoun Kim ◽  
Byeongmun Hwang ◽  
Seongsik Kang ◽  
...  

Background: The GlideScope® videolaryngoscope (GVL) is widely used in patients with difficult airways and provides a good glottic view. However, the acute angle of the blade can make insertion and advancement of an endotracheal tube (ETT) more difficult than direct laryngoscopy, and the use of a stylet is recommended. This randomized controlled trial compared Parker Flex-It™ stylet (PFS) with GlideRite® rigid stylet (GRS) to facilitate intubation with the GVL in simulated difficult intubations. Methods: Fifty-four patients were randomly allocated to undergo GVL intubation using either GRS (GRS group) or PFS (PFS group). The total intubation time (TIT), 100-mm visual analog scale (VAS) for ease of intubation, success rate at the first attempt, use of laryngeal manipulation, tube advancement rate by assistant, and complications were recorded. Results: There was no significant difference between the GRS and PFS groups regarding TIT (50.3 ± 12.0 s in the GRS group and 57.8 ± 18.8 s in the PFS group, P = 0.108). However, intubation was more difficult in the PFS group than in the GRS group according to VAS score (P = 0.011). Cases in which the ETT was advanced from the stylet by an assistant, were more frequent in the GRS group than in the PFS group (P = 0.002). The overall incidence of possible complications was not significantly different. Conclusions: In patients with a simulated difficult airway, there was no difference in TIT using either the PFS or GRS. However, endotracheal intubation with PFS is more difficult to perform than GRS.


Author(s):  
Serhii Pylypaka ◽  
Tetiana Kresan ◽  
Tatiana Volina ◽  
Iryna Hryshchenko ◽  
Liubov Pshenychna ◽  
...  

Toothed gears are the most common mechanical gears in machine building, which are characterized by high reliability and durability, a constant transfer number, and which can transmit high torque. During toothed gear operation, the surfaces of the teeth slide, which gives rise to friction forces and wears their working surfaces. To prevent this, the surfaces of the teeth need constant lubrication. This paper considers the design of a gear tooth engagement, which does not have friction between the surfaces of the teeth since they roll over each other without slipping. The profile of the tooth of such a gear is outlined by congruent arcs, symmetrical relative to the line that connects the center of rotation of the toothed wheel with the top of the tooth. These symmetrical curves at the top of the tooth intersect at the predefined angle. In the depressions of the wheel, adjacent teeth also intersect at the same angle. Such a condition can be ensured by a curve that at all its points crosses the radius-vector emanating from the coordinate origin, also at a stable angle equal to half of the given one. This curve is a logarithmic spiral. If the number of teeth of the drive and driven wheels is the same, then their teeth are congruent. Otherwise, the profiles of the teeth would differ but they could be outlined by congruent arcs of the same logarithmic spiral of the same length taken from different areas of the curve. The minimum possible angle at the top of the teeth is straight. At acute angle, the toothed gear operation is impossible. To build gear wheels with a right angle at the top of the tooth, it would suffice to set the number of teeth of the drive and driven wheels. The center-to-center distance is calculated using the derived formula. The transfer number of such a gear is variable but, with an increase in the number of teeth, the range of its change decreases. The algorithm of wheel construction is given.


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