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For recovering block-sparse signals with unknown block structures using compressive sensing, a block orthogonal matching pursuit- (BOMP-) like block generalized orthogonal matching pursuit (BgOMP) algorithm has been proposed recently. This paper focuses on support conditions of recovery of any K -sparse block signals incorporating BgOMP under the framework of restricted isometry property (RIP). The proposed support conditions guarantee that BgOMP can achieve accurate recovery block-sparse signals within k iterations.

The paper aims to compare the potential of two popular flexible laws in Pareto distribution family, the Exponentiated generalized Pareto distribution (exGPD) and the Gamma-ParetoIV distribution (GPIVD), for the statistical modeling of inverse synthetic aperture radar (ISAR) imaging data. From the perspective of enhancing compressibility and sparsity of the target echo, a novel model named GPIVD-priorbased Bayesian compressed sensing (GPIVCS) is deducted, the analysis proves that the sparsity and compressibility of the GPIVCS model are obtained, further improve the image quality. And from the perspective of reducing imaging complexity, a Bayesian compressed sensing method based on exGPD prior is proposed (EX-GPCS), compared with the conventional methods, the EX-GPCS method is capable of imaging targets in a short period of time. This paper gives a detailed formula derivation of the imaging process of the above two models. Finally, the stateof-the-art performance of these proposed methods is verified by experiments with a wide range of ISAR images.

Digital measurements have widely been applied to observing signals in the world. Powers and frequencies are both main characteristic of signals. It is obvious that power precision of the signals is affected by resolutions of ADCs. There will be frequency errors if sampling frequencies are less than their lower limits, which was found by Nyquist at 1928. It will be proved true that there would be frequency errors too if sampling frequencies are larger than their supper limits in this paper, which are proportional to precisions in S-domain, and inversely proportional to resolutions of ADCs.

To evaluate the safety and efficacy of the domestic foldable one-piece aspheric intraocular lens (IOL, Model: A1-UV) for the treatment of cataract.A prospective randomized controlled clinical research were conducted. One hundred and nineteen cases (119 eyes) of cataract patients were randomly assigned to the study group (58 cases) and the control group (61 cases). The study group were implanted with the domestic made aspheric intraocular lens (Model: A1-UV) and the control group were implanted with imported aspheric intraocular lens (Model: SN60WF, Alcon Laboratories, Inc.). The visual acuity and the slit lamp examination were evaluated 1-2 day, 1 week, 1 month, 3 months, 6 months and 1 year postoperatively. In addition, the contrast sensitivity tests were carried out 3 months, 6 months and 1 year postoperatively. Data were analyzed by chi-square test and independent t-test.100 patients had completed 1 year of follow-up, among which 49 cases were from the study group and 51 cases were from the control group. No severe inflammation or complications associated with intraocular lens were noted in either group within 1 year follow-up. The mean BCDVA, BCNVA, UCDVA, UCNVA(Log MAR) of the study group and the control group were 0.04±0.11, 0.11±0.17, 0.13±0.20, 0.35± 0.19 and 0.07±0.15, 0.15±0.20, 0.18±0.23, 0.41±0.21 at 1 year postoperatively. No statistically significant differences were noted between groups in mean BCDVA, BCNVA, UCDVA, UCNVA (t=-1.39, P=0.166; t=- 1.25, P=0.216; t=-1.06, P=0.292; t=-1.59, P=0.116) at 1 year postoperatively. And there was no significant difference in visual acuity between the two groups (P0.05) 1-2 day, 1 week, 1 month, 3 months and 6 months postoperatively. The difference of the contrast sensitivity between the two groups was not statistically significant (P0.05), besides the contrast sensitivity of the study group was significantly better than the control group at 12c/d, 18 c/d under bright light(t=2.18, P=0.031; t=2.67, P=0.009) at 3 months postoperatively. And the mean contrast sensitivity of the study group and the control group at 12c/d, 18 c/d under bright light were 1.31 ± 0.36, 0.86 ± 0.41 and 1.15 ± 0.40, 0.65 ± 0.44 at 3 months postoperatively.The safety and efficacy of the domestic made foldable one-piece aspheric intraocular lens (Model: A1-UV) for the treatment of cataract is equivalent to the imported aspheric intraocular lens (Model: SN60WF).

Posterior chamber intraocular lens implantation combined with lensectomy-vitrectomy and/or removal of intraocular foreign bodies in one operation was performed on 12 patients with ocular injuries involving both anterior and posterior segments. There were 6 cases with intravitreal or intraretinal foreign bodies, 3 cases with lens dislocation in the vitreous by blunt trauma and 3 cases with vitreous hemorrhage and cataract. Pre-operatively, the visual acuities of all patients ranged from light perception to 0.02, while postoperatively, their visual acuities were 0.5-1.5 in 8 cases, 0.3 in 2 cases, finger counting and 0.05 in other 2 cases which were related to optic nerve atrophy and retinal vein occlusion, respectively. The results suggest that the combined surgery benefit the fast visual rehabilitation in selected young patients with unilateral ocular injuries.

Multivariated analysis of corrected visual acuities after extraction of congenital cataract with IOL implantation in 24 patients (41 eyes), including 14 children (22 eyes) under 12 years of age, revealed that 6 factors significantly affected the postoperative results, namely, the pattern of lenticular opacity, monocularity, strabismus, nystagmus, after-cataract formation and its time of onset. Therefore, operation as early as possible is recommended for cases with these factors and IOL implantation considered, with discretion, in children for whom other forms of visual aids are not available.

Primary implantation of posterior chamber intraocular lens (PC IOL) was performed in 70 eyes with defective posterior capsule following extracapsular cataract extraction. The visual acuity was 0.5 or better at 3 months and 12 months postoperative in 97.1% and 88.6% of the cases respectively. Complications were rare. The authors put forth the following principles for such cases: (1) injection of air or Healon to maintain a deep anterior chamber: (2) the insertion or rotation of the IOL should be away from the area of capsular rupture; (3) the long axis of the IOL should cross the meridian of the posterior capsule rupture: (4) the residual anterior capsule may be utilized to support the IOL; (5) complete clearance of any vitreous in the anterior chamber; and (6) performance of at least 2 peripheral iridectomies to guard against pupillary block. This technique is applicable in eyes with peripheral posterior or capsule defect of less than 120 degrees or with central rupture of less than 4mm.

By transscleral suture fixation, posterior chamber IOLs were implanted in 29 eyes (27 patients), including secondary implantation in 13 eyes 6 months to 10 years after intracapsular cataract extraction, fixation of dislocated IOL in 2 eyes, and primary implantation in 14 eyes with ruptured capsules due to complicated extracapsular extraction or traumatic cataract. All the patients enjoyed better postoperative vision, e.g. 20/20 or better in 20 eyes (69%) and 20/40 or better in 27 eyes (93.1%). Complications occurred in 2 eyes, one of cystoid macular edema and the other of early IOL tilt. This technique makes it possible for almost all eyes after cataract extraction to be implanted posterior chamber IOL.

Pupil capture is a rare complication in posterior chamber intraocular lens implantation. Among 259 eyes with PC IOLs, pupil capture was noted in 6 eyes (2.3%), all J-loop planar lenses (6/119 or 5%), while none of the other 140 eyes with angled or modified J-loop lenses had pupil capture. The complication was successfully corrected by a loop compression maneuver through the sclera, and the patients had visual acuities over 1.0 on follow-up. Based on clinical observations and an experimental model, it was presumed that the arching forward of planar lenses could be the major cause of pupil capture.

91 patients with acute nonlymphoblastic leukemia (ANLL) were treated with Homoharringtonine, Cytosine arabinnoside, Thioguanine (HAT) and/or Daunorubicin, (Adriamycin) Cytosine arabinnoside, Thioguanine D(A) AT protocols. The total CR rate was 68.1% with a median remission duration of 20.3 months, and the expectant survival rate in 5 years (Kaplan-Meier method) was 39%. The CR rate and the CR duration projected by HAT and D (A) AT protocols were very similar. After 20 prognostic factors from both clinical and laboratory examinations prior to treatment had been analysed, we concluded that (1) The CR rate was improved by increasing the dose of induction chemotherapy; (2) The patients might have longer remission and survival if they obtained remission in 2 courses of treatment; (3) The remission durations were comparable between the individuals receiving and not receiving maintenance chemotherapy.

The B19 parvovirus, a small single-stranded DNA virus of 5.4 kilobases, is pathogenic in humans. B19 has remarkable specificity for erythroid progenitor cells and has been propagated in vitro only with human erythroid bone marrow. Replication of viral DNA and the viral protein products of B19 appear similar to those of other animal parvoviruses. However, B19 transcription had unusual features in comparison with that in other animal parvoviruses. At least nine overlapping poly(A)+ transcripts were identified in infected cells; all but one contained large introns. B19 differed from other parvoviruses in the initiation of all transcripts at a strong left side promoter (p6) and the absence of a functional internal promoter; the presence of short 5' leader sequences of about 60 bases and very large introns for RNAs encoded by the right side of the genome; two separate transcription termination sites, in contrast to cotermination at the far right side of the genome for other parvoviruses; the probable utilization by three transcripts of a variant polyadenylation signal (ATTAAA or AATAAC) in the middle of the genome; and the abundance of two unique transcripts from the middle of the genome which did not code for capsid proteins. The unusual transcription map of B19 suggests that regulation of the relative abundance of transcripts occurs by splicing and termination-polyadenylation events rather than by promoter strength. In combination with the published nucleotide sequence, the novel transcription map separated the pathogenic B19 virus at a molecular level from other animal parvoviruses and human adeno-associated virus.