M2U-net: Effective and efficient retinal vessel segmentation for real-world applications

In this paper, we present a novel neural network architecture for retinal vessel segmentation that improves over the state of the art on two benchmark datasets, is the first to run in real time on high resolution images, and its small memory and processing requirements make it deployable in mobile and embedded systems. The M2U-Net has a new encoder-decoder architecture that is inspired by the U-Net. It adds pretrained components of MobileNetV2 in the encoder part and novel contractive bottleneck blocks in the decoder part that, combined with bilinear upsampling, drastically reduce the parameter count to 0.55M compared to 31.03M in the original U-Net. We have evaluated its performance against a wide body of previously published results on three public datasets. On two of them, the M2U-Net achieves new state-of-the-art performance by a considerable margin. When implemented on a GPU, our method is the first to achieve real-time inference speeds on high-resolution fundus images. We also implemented our proposed network on an ARM-based embedded system where it segments images in between 0.6 and 15 sec, depending on the resolution. Thus, the M2U-Net enables a number of applications of retinal vessel structure extraction, such as early diagnosis of eye diseases, retinal biometric authentication systems, and robot assisted microsurgery

Evaluation of some feeding indices of Pomadasys kaakan in the northern Persian Gulf

In this paper the Vacuity Index (VI), Fullness Index (FI) and Food Preference Index (FPI) for the stomach contents of Pomadasys kaakan were evaluated to assess the quantity and kind of food which this fish consumes in the Persian Gulf. A total of 227 specimens were collected from fishing trawlers or landings from November 2005 to September 2006. 24.7% of stomachs were full, 11.9% were semi-full and 63.4% were empty. The seasonal average of VI was 77.4, 44.6, 80.0 and 54.0 % for autumn, winter, spring and summer, respectively. The overall FI was 36.6 with seasonal averages of 22.6, 55.4, 20.0 and 46.0 in autumn, winter, spring and summer, respectively. The main stomach contents were crustaceans (esp. crab & shrimp), fish, mollusks (bivalves, gastropods and cuttlefish), stomatopoda, brittle stars, Lingula sp. and sea weeds. The estimated FPIs for crustaceans were 77.7, fish 32.1, mollusks 28.6 and echinoderms 18.8 %. Overall, the results show that this fish is a relatively frugal species which consumes crustaceans as main food and has adopted itself with ecological changes of the Persian Gulf

Periodically-Poled Silicon [Updated]

We propose a new class of photonic devices based on periodic stress fields in silicon that enable second-order nonlinearity as well as quasi-phase matching. Periodically-poled silicon (PePSi) adds the periodic poling capability to silicon photonics, and allows the excellent crystal quality and advanced manufacturing capabilities of silicon to be harnessed for devices based on second-order nonlinear effects. As an example of the utility of the PePSi technology, we present simulations showing that mid-wave infrared radiation can be efficiently generated through difference frequency generation from near-infrared with a conversion efficiency of 50%. This technology can also be implemented with piezoelectric material, which offers the capability to dynamically control the X(2) nonlinearity.Comment: 11 pages, 4 figure

Time course of changes in passive avoidance and Y-maze performance in male diabetic rats

Diabetes mellitus is accompanied with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Therefore, this research study was conducted to evaluate time-dependent changes in passive avoidance and Y-maze performance in male diabetic rats. For this purpose, male Wistar rats were randomly divided into control and diabetic groups. For induction of diabetes, streptozotocin (STZ) was injected i.p. at a single dose of 60 mg/kg. For evaluation of learning and memory, initial latency (IL) and step-through latency (STL) were determined at the end of 1st, 2nd, and 3rd months using passive avoidance and Y-maze tasks. It was found out that mean IL exhibits a significant increase only at the end of 2nd (p<0.05) and 3rd (p<0.01) months. In addition, STL significantly reduced at the end of 2nd (p<0.05) and 3rd months (p<0.01). Regarding Y-maze task, alternation score of the diabetic rats was lower than that of the control ones at the end of 1st (p<0.05), 2nd (p<0.01), and 3rd (p<0.01) months as compared to time-matched control group. To conclude, at least one month is strictly required for development of behavioral disturbances in passive avoidance and Y-maze tasks in STZ-diabetic rats

Predictors of physical restraint in a psychiatric emergency setting

Background: Considering the negative consequences of using physical restraints, we conducted this study to identify patients who are more frequently restrained in a psychiatric emergency ward as an initial step to limit the use of restraint to the minimum possible. Methods: This was a retrospective case control study conducted in Iran Psychiatric Hospital in Tehran, Iran. We reviewed the files of 607 patients who were admitted during a one year period using convenience sampling; of them, 186 were in the restrained group and 421 in the unrestrained group. Results: Surprisingly, no significant difference was found between the restrained and unrestrained groups in demographic characteristics. The patients who were referred because of violence were diagnosed as having methamphetamine induced psychotic disorder or bipolar I disorder in manic 1episode and had a higher odds of being restrained (OR=2.51, OR=1.61, and OR=1.57 respectively). Being restrained was also associated with a longer duration of hospitalization and duration of staying in the emergency ward. Moreover, patients in their first admission were more frequently restrained. Conclusion: Medical and nursing staff should consider special measures for the patients who are at a higher risk for being restrained. More frequent visits and education for both patients and staff may be effective in reducing the number of physical restraints for these groups of patients

Identification of insect community inhabiting Kaas plateau, Western ghats through cytochrome oxidase subunit I gene

Kaas Plateau is located in Western Ghats of Maharashtra, India. The region is one of its kinds being a biodiversity hot spot declared by UNESCO representing rich biodiversity of Western Ghats in India. However, insect biodiversity of this region has not been studied in detail so far. Thus, the present study was aimed at identification of insect community based on mitochondrial gene, cytochrome c oxidase subunit I (MT-CO1), for quick and reliable identification. During a collection trip, several insect specimens were collected, which belonged to seven insect orders, viz., Lepidoptera, Coleoptera, Hemiptera, Hymenoptera, Diptera, Orthoptera and Thysanoptera. Based on their morphological characteristics, specimens collected were delineated in to various orders and families. This resulted in determination of possible 15 different insect species, of which 7 could be identified up to species level. Remaining 8 sequences were matched with existing GenBank database that was > 96%, therefore, were considered as putative species. One specimen could be identified up to genus level, viz., Cicindela sp. and one up to family level - Pentatomidae and six up to order level only, i.e., Coleoptera, Diptera, Lepidoptera, Orthoptera and Thysanoptera (2 specimens). The results suggested that 50% of the community could be identified to species level with MT-CO1 gene and at least about 8 specimens could possibly be new species for India. The insects thus collected from Kaas plateau were molecularly identified and at least 50% of collections were delineated to species level on the basis of their DNA barcodes for the first time

Relativistic effects in the chaotic Sitnikov problem

We investigate the phase space structure of the relativistic Sitnikov problem in the first post-Newtonian approximation. The phase space portraits show a strong dependence on the gravitational radius which describes the strength of the relativistic pericentre advance. Bifurcations appearing at increasing the gravitational radius are presented. Transient chaotic behavior related to escapes from the primaries are also studied. Finally, the numerically determined chaotic saddle is investigated in the context of hyperbolic and non-hyperbolic dynamics as a function of the gravitational radius.Comment: 8 pages, 11 figure

Abelian Higgs Hair for a Static Charged Black String

We study the problem of vortex solutions in the background of an electrically charged black string. We show numerically that the Abelian Higgs field equations in the background of a four-dimensional black string have vortex solutions. These solutions which have axial symmetry, show that the black string can support the Abelian Higgs field as hair. This situation holds also in the case of the extremal black string. We also consider the self-gravity of the Abelian Higgs field and show that the effect of the vortex is to induce a deficit angle in the metric under consideration.Comment: REVTEX4, 12 pages, 6 figures, The version to be appeared in Phys. Rev.