Leakage Spots Research Articles

Wait-and-see and other factors associated with recurrence risk in central serous chorioretinopathy patients: A systematic review and meta-analysis of cohort studies

Background: Central serous chorioretinopathy (CSC) is a common macular disease characterized by serous retinal detachment and leakage spots at the level of the retinal pigment epithelium. While acute CSC is often self-limiting, chronic and recurrent CSC can lead to permanent vision loss. The identification of risk factors associated with recurrent CSC is crucial for preventive measures and appropriate management. This systematic review aims to determine the various risk factors for the recurrence of central serous chorioretinopathy, with a particular focus on the "wait and see" approach and other contributing factors. Methods: The review protocol was registered in PROSPERO (ID: CRD42023413852). A systematic literature search was conducted across four databases (PubMed, Cochrane, Embase, and ScienceDirect) using the keywords "((Central serous chorioretinopathy) AND (Recurrence) AND (Risk))". Meta-analyses were performed using Review Manager 5.4. Results: A total of five studies met the inclusion criteria for all factors, while three studies were selected for meta-analyses regarding the "wait and see" approach. The analysis revealed four significant risk factors for CSC recurrence: patient's clinical condition, therapy administration, age and gender, and patient history. Additionally, a meta-analysis based on three studies involving 1025 eyes demonstrated a statistically significant difference between CSC patients who received no therapy (wait and see) and those who underwent specific therapeutic interventions, with a relative risk of 1.82 (95% CI 1.49–2.22, I2 95%, P <0.00001). Conclusions: Early identification of risk factors, including the ‘wait and see’ approach and other factors, is crucial in preventing the recurrence of central serous chorioretinopathy. Patients at high risk of recurrence should receive vigilant treatment and routine monitoring to avoid permanent vision loss. This systematic review provides valuable insights for clinical decision-making and emphasizes the importance of individualized management strategies for CSC patients.

Refractory Age-Related Macular Degeneration Due to Concurrent Central Serous Chorioretinopathy in Previously Well-Controlled Eyes

Background: During the treatment of age-related macular degeneration with anti-vascular endothelial growth factor (VEGF) drugs, we often see cases with anti-VEGF-resistant refractory subretinal fluid. In this report, we present two cases of anti-VEGF-resistant refractory age-related macular degeneration (AMD) due to the concurrent development of central serous chorioretinopathy (CSCR) in eyes previously well controlled with intravitreal anti-VEGF injections. Case presentation: Two patients underwent intravitreal aflibercept for the treatment of neovascular AMD. Initially, both patients responded well to intravitreal aflibercept, resulting in the complete resolution of the subretinal fluid. However, both patients subsequently developed sudden-onset refractory subretinal fluid that did not respond to repeated intravitreal aflibercept. Fluorescein angiography, indocyanine green angiography, and swept-source optical coherence tomography revealed focal leakage spots, choroidal hyperpermeability, and dilated choroidal vessels, respectively, which were distinct from the pre-existing choroidal neovascularization and suggestive of newly developed CSCR. Laser photocoagulation of the leak spots resulted in the complete resolution of the once-refractory subretinal fluid and the maintenance of vision. Conclusions: Our cases highlight that anti-VEGF-refractory subretinal fluid may occur secondary to concurrent CSCR in patients receiving regular anti-VEGF treatments for AMD. In those patients, treatment for CSCR is effective for controlling subretinal fluid that is unresolved by anti-VEGF treatment.

Quantitative corrosion detection of reinforced concrete based on self-magnetic flux leakage and rust spot area

The internal rebar corrosion of reinforced concrete (RC) structures harm the bearing capacity and durability of structures. Existing methods can measure rebar corrosion but are unsuitable for RC structures. Given this, the self-magnetic flux leakage (SMFL) field of V-shaped rebar corrosion damage was analyzed according to the magnetic dipole model, and the parameter K was proposed to characterize the corrosion degree. Using the naive Bayes algorithm, the SMFL method and the rust spot area analysis method were correlated to propose a rebar corrosion detection method. A corrosion detection experiment was conducted on RC specimens. The results showed that the parameter K was linearly correlated with the maximum cross-sectional rust loss rate η. Using the parameter K to evaluate the rust degree, the accuracy of rebar rust classification was 70%. After introducing the rust spot area ratio S as a supplementary parameter, the accuracy of rebar rust classification increased by 12.5% to 82.5%. This indicates that the proposed method could quantitatively detect the corrosion of the rebars within the concrete.

A Shale Gas Leaking Incident in Fuling Shale Gas Field in Chongqing, China: A Case Study

A ground natural gas leaking event at the Fuling shale gas field is reported in this paper. Thirteen leakage spots were discovered in two places near the SW-1 and SW-2 drilling wells. The biggest leak rate was above 1000 m3 per day, and no H2S was identified in any of the 13 leaking spots, according to the field study. The chemical components, carbon isotope properties of the leaking gases, and the geological context of the leaking location were researched in order to determine the reason for the leaking incident. From the geological conditions, the Shimen 1# fault belt cuts the whole strata from bottom to top, according to seismic reverse time migration (RTM), and the fault and leaking spots are located in the range of the surface projection of the horizontal section of the adjacent shale gas well. The fracture development evaluation shows that the Wufeng–Longmaxi Formation, which is also the producing layer of the Fuling shale gas field, has a very high possibility of fracture development. From the geochemical view, the carbon isotope of the leaking gases lies in the range of the Wufeng–Longmaxi Formation, showing that the Wufeng–Longmaxi Formation is the gas source of the leaking gas.

Characterization Of Gallium Oxide With A Novel Non-Contact Electrical Metrology, CnCV, For Wide Bandgap Semiconductors

Purpose of Work Cost savings and short feedback time are significant advantages of the corona non-contact capacitance voltage (CnCV) technique1, recently introduced for wide bandgap SiC, GaN, and AlGaN/GaN as a replacement for C-V measurements on fabricated electrical test structures. The goal of this work is to verify the basic applicability and effectiveness of CnCV in the characterization of Gallium Oxide. The results demonstrate excellent measurement conditions on Ga2O3 epitaxial and bulk grown wafers, enabling the determination of the entire set of electrical properties in Table 1 and in Figures 1 to 5. Results and Discussion Non-contact electrical measurements with the CnCV technique involve electric charge dosing, ΔQ, by corona discharge in air. The response of the semiconductor is monitored as a surface voltage change, ΔV, measured with a vibrating Kelvin probe. A unique combination of charge, voltage, capacitance (C=ΔQ/ΔV), and leakage current, J=CdV/dt, measured in depletion enables the determination of the whole set of electrical properties presented in Table 1. The state-of-the-art CnCV tool by Semilab SDI was modified to include a 255nm UV light source, which provided excellent corona charge removal, restoring the Ga2O3 surface to a pre-charged condition needed for repeated measurements. An absolute Kelvin-probe calibration with a Ag/AgCl reference half-cell allowed for the quantification of the work function, WF, and electron affinity, X.A critical requirement for CnCV applicability is the stability of deposited corona charge with respect to the magnitude of charge under the Kelvin probe and the aerial charge distribution. In this work, the assessment of charge stability on Ga2O3 surfaces was performed using surface voltage profiling after charging. An excellent stability condition was established with a thermal desorption treatment commonly used in semiconductor measurements. A constant and stable charging profile was maintained up to a maximum depletion field of about 3.5MV/cm for epitaxial surfaces and polished surfaces of bulk grown Ga2O3 wafers.In the CnCV metrology, surface voltage mapping is used for identification of the electrical activity of defects. Such mapping of Ga2O3 after full wafer charging revealed the absence of high leakage spots which is probably the most significant difference compared to SiC. This difference is evident from the corresponding maps in Fig. 1 and Fig. 2 for Ga2O3 and 4H-SiC, respectively. The red spots in the 4H-SiC map are defects with the largest electrical activity, such as 3C-SiC related micro-structures2,3. No defect spots were observed in Ga2O3 maps. This significant result may be a consequence of the low probability of the poly-type inclusions in Ga2O3.Examples of non-contact C-V and corresponding 1/C2 characteristics are shown in Fig. 3 for epi-Ga2O3. These results give a constant dopant depth profile in Fig. 4. According to the initial capacitance, C0, the Ga2O3 surfaces are initially in depletion with negative surface charges as given in Table 1. The presently determined electron affinity, X, was uniform across the sample (see Fig. 5). The value 3.6 ± 0.1 is close to the literature range.In summary, we conclude that CnCV is a powerful alternative to standard C-V and mercury C-V and shall prove very useful in the investigation of important fundamental properties of Ga2O3 and the practical development and process control of emerging Ga2O3 power devices.

Efficacy of Navigated Laser Photocoagulation for Chronic Central Serous Chorioretinopathy: A Retrospective Observational Study.

Background. No consensus has been reached regarding the management of central serous chorioretinopathy (CSCR). We aimed to investigate the efficacy of navigated laser treatment for chronic CSCR and changes in the morphology of the retinal pigment epithelium (RPE). In this retrospective observational study, 19 patients with subjective symptoms admitted to the Nanjing Medical University Affiliated Eye Hospital were included between January 2021 and August 2021. All patients underwent visual acuity and optical coherence tomography (OCT) examination during follow-up. Fluorescein angiography (FA) was performed at baseline and at the final follow-up to confirm the dye leakage sites. The mean logMAR BCVA at baseline and at the end of follow-up was 0.49 ± 0.24 and 0.24 ± 0.15, respectively. The mean logMAR BCVA 3 months after treatment was significantly better than that before treatment (p = 0.002). Significant improvements were observed in central macular thickness (CMT) and subfoveal choroidal thickness (SFCT) after navigated laser photocoagulation (p < 0.0001). Subretinal fluid was completely resolved in 13 (68%) of 19 eyes at 3 months. RPE lesions on OCT images showed RPE detachment in 17 eyes (61.5%), small protrusion of the RPE layer in 5 eyes (7.5%), and a rough RPE layer in 4 eyes (31%). After laser treatment, 9 points (35%) showed retinal detachment, and 10 (38.5%) regions showed an irregular RPE layer. An irregularly protruded RPE layer was also observed in different regions of the leakage spot in 5 (19%) eyes, and RPE defects were seen in 2 (7.5%) eyes. Navigated laser photocoagulation for chronic CSCR can achieve substantial anatomical and visual improvement. OCT outcomes may provide new information to facilitate understanding of the mechanism of chronic CSCR. Navigated laser photocoagulation should be chosen as an optimal treatment option in patients with chronic CSCR who cannot afford photodynamic therapy.

Field measurements of fugitive methane emissions from three Australian waste management and biogas facilities.

A key environmental sustainability requirement for the treatment of organic waste via anaerobic digestion (AD) is the prevention of unwanted methane emissions in the production chain whenever possible. Identifying and quantifying these emissions has been frequently investigated, particularly in Europe. However, the challenges of climate change are also becoming vitally important in Australia. This novel study presents the results from emission measurement campaigns carried out at two biogas plants and one landfill site in Australia. An on-site approach consisting of leakage detection and emission quantification by a static chamber method was applied. Twenty-nine leakages were detected predominantly on the digesters (gastight covered anaerobic lagoons) of the biogas plants. Ten emission hot spots were found on the surface cover of a landfill site. Methane emission rates of 9.9±2.3kgh-1 (10.5±2.4% CH4) for biogas plant A, 3.0±1.9kgh-1 (8.1±5.2% CH4) for biogas plant B and 41-211gh-1 for the two largest emission hot spots from the landfill were measured. Since not every single leakage or hot spot could be quantified separately, the stated overall emission rates had to be extrapolated. Importantly, the emission rates from the landfill should be interpreted carefully due to the limited overall area which could be practicably investigated. Leakages occurred at common components of the covered anaerobic lagoons such as the membrane fixation or concrete walls. Repairing these parts would increase the plant safety and mitigate negative environmental effects.

Service Selection Attributes of the Hospital Companion Focusing on the National Policy Design Task of Gwangsan-gu Office in Gwangju Metropolitan City

본 연구의 목적은 광주광역시 광산구에서 국민정책디자인 과제로 추진하고 있는 건강약자에 대한 병원동행 서비스가 안정적으로 확산·정착할 수 있는 논거를 마련하는 것이다. 이를 위해 병원동행 서비스의 누수 및 사각지대를 최소화 될 수 있도록 서비스 대상인 건강약자에 대한 정의를 명확히 하였고, 국민정책디자인 과제 수행에서 다루지 않은 병원동행자의 서비스 선택속성에 대한 통계분석을 통해 서비스 필요성에 대한 객관적인 근거를 제시하였다. 연구결과 건강약자는 ‘신체적, 정신적으로 불편하여 지속적인 병원 진료가 필요하나 병원동행 없이는 이동이 불가능 한 사람’으로 정의하였고, 병원동행자의 서비스 수요도 다양한 집단에서 나타나고 있는 것을 확인하였다. 또한, 병원동행 서비스가 비즈니스 모델로 자리잡기 위한 제도적 개선, 병원동행 차량에 대한 지위 문제 명문화, 병원동행 서비스의 확장성에 대한 시사점을 도출하였다.The purpose of this study is to provide a rationale for stably spreading and establishing the hospital accompaniment service for the health vulnerable, which is being promoted as a national policy design project in Gwangsan-gu, Gwangju. In order to minimize leakage and blind spots of the hospital accompaniment service, the definition of the health vulnerable who are the target of the service was clarified, and objective grounds for service necessity were presented through statistical analysis on the service selection attributes of hospital companions, which were not addressed in the implementation of the national policy design task. As a result of the study, the infirm was defined as ‘a person who is physically and mentally uncomfortable and needs continuous hospital treatment, but is unable to move without a hospital companion’, and it was confirmed that the service demand of hospital companions also appeared in various groups. In addition, we drew implications for institutional improvement to establish the hospital companion service as a business model, stipulating the status issue for hospital companion vehicles, and scalability of hospital companion service.

Molecular Phylogenetics and Population Genetics of the Dengue Vector Aedes aegypti From the Arabian Peninsula.

Aedes aegypti mosquito is the principal dengue vector in the Kingdom of Saudi Arabia (KSA); however, no study has addressed its ecology and population structure yet. Therefore, we report on Ae. aegypti phylo- and population genetics using three DNA markers: COI, ND4, and rDNA-ITS2. Sampling the immature stages of Ae. aegypti revealed that water storage tanks (34.3% of habitats) were the most productive and contained 33% of immatures stages. Other important habitats included containers for wastewater drainage (including air-conditioning and water cooler trays) and containers associated with ornamentation. Shallow water leakage spots (2.7% of habitats, 8% of immatures) can be considered rare-but-epidemiologically-important containers. Neighbor-joining (NJ) phylogenetic analysis of Ae. aegypti identified 8, 14, and 9 haplotypes of COI, ND4, and ITS2, respectively, and revealed high levels of genetic variation in Ae. aegypti populations of KSA. Global distribution of haplotypes also indicated multiple gene introductions into these populations, with high levels of intra-population genetic variation and continuous gene exchange. The neutrality values indicated a deficiency of alleles and suggested that the KSA Ae. aegypti loci tested did not follow a neutral model of molecular evolution. Fst values and AMOVA indicated that most of the genetic variation in the KSA Ae. aegypti populations is due to intra- rather than inter-population differences. This is the first comprehensive report on the phylo- and population genetics of Ae. aegypti from the Arabian Peninsula. This information expands our understanding of the ecology and population dynamics of this important arboviral vector for informed control efforts.

Temperature Flows in Railway Tunnels: Field Measurements of Frost Penetration

Even though extensive pre-grouting is carried out during the construction of tunnels, certain leakages and drips remain. These remaining leakages are remedied by a combination of post-injection and drainage measures with, for example, frost insulated drain mats, whose function is to prevent the cold tunnel air from reaching a leakage spot and causing water to freeze. Despite these measures, some water may still enter the tunnels and cause problems during winter with ice formations and frost shattering. Icicles, ice pillars and ice-covered roads and railway tracks require constant maintenance. If ice occurs in the fracture network close to the tunnel contour or in the interface between the rock and shotcrete, it can cause degradation of the load-bearing capacity of the tunnel and fall-outs of both materials. In tunnel sections with water leakage problems it is common to protect the load-bearing structure from freezing with insulated drainage systems. To determine where along the tunnel efforts must be made to prevent ice formation, the temperature conditions of tunnels must be investigated. This article presents parts of the results from field measurements in two Swedish railway tunnels. The measurements involves monitoring of air and rock temperatures, air pressure and air velocity. Keywords: Frost penetration, ice formation, frost shattering, temperature measurement, maintenance, railway tunnel.

Surface termination effects on the electrical characteristics of La2O3/Al2O3 nanolaminates deposited by atomic layer deposition* *Project supported by the National Natural Science Foundation of China (Grant Nos. 61604016 and 51802025), China Postdoctoral Science Foundation (Grant No. 2017M613028), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 300102319209 and 300102310501) and the Innovation, and Entrepreneurship Training Program for Undergraduates

Effects of initial surface termination on electrical characteristics of La2O3/Al2O3 nanolaminates deposited by atomic layer deposition are studied by conductive atomic force microscopy working in contact mode and standard electrical characterization methods. It is found that, compared with La2O3/Al2O3 nanolaminates with LaO x as termination, lower interface trap density, less current leakage spots, and higher breakdown voltage are obtained in the La2O3/Al2O3 nanolaminates with AlO x as termination after annealing. A clear promotion of interface silicate layer is observed for La2O3/Al2O3 nanolaminates with AlO x as termination compared with LaO x as termination under the same annealing condition. In addition, the current conduction mechanism in La2O3/Al2O3 nanolaminates is considered as the Poole–Frenkel conduction. All results indicate that the AlO x is a more appropriate termination to deposit La2O3/Al2O3 nanolaminates on Si substrate, which is useful for the high-κ process development.

Investigation of Dislocations Inducing Leakage Current on SiC Junction Barrier Schottky Diode by Two-Photon-Excited Band-Edge Photoluminescence

Tilt angles of threading dislocations (TDs) which induce leakage of current on SiC junction barrier schottky diodes (SiC-JBSs) were investigated by two-photon-excited photoluminescence (2PPL) and transmission electron microscopy (TEM). Observation of leakage spots measured by atomic force microscopy (AFM) revealed that pit-like structures were certainly formed but the depths were considerably shallow, indicating that influence of local electric field due to the structures was negligible on our SiC-JBSs. It became clear that tilt angles of the TDs inducing leakage were relatively larger than about 11° by 2PPL and that the TD was the threading mixed dislocation by TEM.

&lt;p&gt;Risk of Recurrence and Transition to Chronic Disease in Acute Central Serous Chorioretinopathy&lt;/p&gt;

PurposeTo study the risk of recurrence in acute central serous chorioretinopathy (aCSC) and to evaluate the risk of transitioning to chronic CSC.Patients and MethodsThe medical records and multimodal imaging data of 295 aCSC cases were reviewed. Typical aCSC was defined as the presence of serous subretinal fluid (SRF), one focal leakage spot on fluorescein angiography (FA), retinal pigment epithelium (RPE) alterations limited in area to less than one optic disc diameter, and complete recovery from this first CSC episode. An increase in RPE alterations combined with persistent SRF was considered a sign of chronicity, which was determined in cases with >12 months follow-up. The main outcome measures included final visual acuity, percentage of disease recurrence, and percentage of cases moving toward a chronic phenotype. Treatment strategies and their efficacy were also reviewed.ResultsA total of 295 eyes in 291 patients with aCSC were included. Spontaneous recovery was awaited in 154 eyes (52%), whereas 141 eyes (48%) recovered following treatment. SRF recurrence occurred in 24% of untreated cases and in 4% of treated cases (p<0.001). An analysis of 61 eyes that underwent an FA after ≥12 months of follow-up revealed increased RPE alterations in 22 eyes (36%), and 14 eyes (23%) had both an increase in RPE alterations and SRF recurrence.ConclusionAll aCSC cases recovered from the first disease episode, and none of the cases developed persistent SRF leakage. Among the cases for which long-term follow-up information was available, 36% showed a tendency toward chronicity in terms of increased RPE alterations, whereas 23% showed both an increase in RPE alterations and recurrent SRF. Early photodynamic therapy (PDT) may decrease the risk of recurrences.

Study of flow ripple characteristics in an innovative two-dimensional fuel piston pump

To meet the requirements of fuel pumps with high efficiency, high power density, and low flow ripple for modern advanced aircraft, we hereby propose a two-dimensional piston pump (called 2D pump). A single piston with both rotary and linear motions is used to combine the flow distributing and volumetric varying functions together. The leakage spots are reduced to the clearance between the piston and the cylinder. As the radial force of the piston is balanced, a small piston clearance is selected to reduce leakage. Furthermore, a 2D tandem pump formed by two 2D pump units connected in series was introduced to eliminate the geometric flow ripple. The flow ripple characteristics were studied through analytical techniques, CFD numerical methods, and experiments. The results show that the flow ripple of 2D pump obtained by the measured pressure wave is 6.3%, while the pump has a high volumetric efficiency of up to 96% within a speed range of 1000–8000 r/min, indicating that reducing the leakage increases the average actual flow and reduces the flow ripple. Therefore, the proposed 2D pump is suitable for modern advanced aircraft.

Spectral responses and identification of surface vegetation stressed by natural gas leakage

ABSTRACT The leakage of natural gas from underground storages can cause economic, safety, and ecological problems. However, when the leakage is slight, the gas concentration in surface atmosphere cannot reach the threshold for direct monitoring. Hyperspectral remote sensing can indirectly detect it through the spectral changes of vegetation in the leak area. A field experiment was performed, which took bean, corn and grass as test plants, to study the characteristics of canopy spectral changes under natural gas leakage stress. The results showed that the spectra of stressed vegetation changed significantly after three days of gas injection, which manifested an increase in the visible bands of 570–700 nm and a decrease in the near-infrared of 760–1000 nm. By performing ANOVA (Analysis of Variance) on the spectra of vegetation in the control and experimental plots, the bands with p< 0.05 and bigger F values were selected as the sensitive bands. And the natural gas stress index was constructed using the selected bands. A quantitative test by JM (Jeffries-Matusita) distance showed that the index could well identify (JM > 1.8) the stressed vegetation throughout the phenological plant cycle. This study can be applied to detect underground natural gas storage leakage spots by hyperspectral remote sensing.

Swept-Source Optical Coherence Tomography Angiography in Central Serous Chorioretinopathy

Purpose: This article aims to evaluate the appearance of central serous chorioretinopathy (CSC) with swept-source optical coherence tomography angiography (SS-OCTA), to discuss whether localization of the leakage spot seen on fluorescein angiography (FA) corresponds to any recognizable spot on SS-OCTA, and to provide subsequent diagnosis of choroidal neovascularization (CNV) in the course of CSC. Methods: A prospective interventional case series was conducted in a private outpatient office on 30 eyes of 27 patients. In addition to ophthalmic examination, FA, spectral-domain OCT, SS-OCT and SS-OCTA were performed at least once. If laser photocoagulation or anti-vascular endothelial growth factor (anti-VEGF) injection was administered, then all examinations were repeated afterward. Following SS-OCTA, morphology features of CSC were analyzed: localization of the leakage spot, presence of feeder vessels, and presence of CNV. Changes after treatment were recorded. Results: In 26 of 30 cases the leakage site on FA corresponded to a highly hyporeflective site on SS-OCTA. In 7 of these cases laser was successfully administered. In 20/30 eyes we additionally observed thickened vessels at the level of choriocapillaris in close proximity to the most hyporeflective spot. CNV was observed in 4 cases. The leakage spot is the most hyporeflective spot on SS-OCTA localized at the level of choriocapillaris. Additionally, choroidal feeder vessels might be visualized at the level of choriocapillaris in 66% of cases. In 4 eyes, CNV in the course of CSC was noted. Conclusions: In CSC, SS-OCTA is a valuable diagnostic tool and its results complement FA. It might add to the treatment process, especially regarding the need to start and to monitor anti-VEGF injections. Anti-VEGF treatment results in fading but not in complete disappearance of CNV in the course of CSC.

Correlation between dislocations and leakage current of p-n diodes on a free-standing GaN substrate

Dislocations that cause a reverse leakage current in vertical p-n diodes on a GaN free-standing substrate were investigated. Under a high reverse bias, dot-like leakage spots were observed using an emission microscope. Subsequent cathodoluminescence (CL) observations revealed that the leakage spots coincided with part of the CL dark spots, indicating that some types of dislocation cause reverse leakage. When etch pits were formed on the dislocations by KOH etching, three sizes of etch pits were obtained (large, medium, and small). Among these etch pits, only the medium pits coincided with leakage spots. Additionally, transmission electron microscopy observations revealed that pure screw dislocations are present under the leakage spots. The results revealed that 1c pure screw dislocations are related to the reverse leakage in vertical p-n diodes.

Leakage current reduction of vertical GaN junction barrier Schottky diodes using dual-anode process

The origin of the leakage current of a trench-type vertical GaN diode was discussed. We found that the edge of p-GaN is the main leakage spot. To reduce the reverse leakage current at the edge of p-GaN, a dual-anode process was proposed. As a result, the reverse blocking voltage defined at the leakage current density of 1 mA/cm2 of a vertical GaN junction barrier Schottky (JBS) diode was improved from 780 to 1,190 V, which is the highest value ever reported for vertical GaN Schottky barrier diodes (SBDs).

Thinging Machine Applied to Information Leakage

This paper introduces a case study that involves data leakage in a bank applying the so-called Thinging Machine (TM) model. The aim is twofold: (1) Presenting a systematic conceptual framework for the leakage problem that provides a foundation for the description and design of a data leakage system. (2) The aim in (1) is developed in the context of experimentation with the TM as a new methodology in modeling. The TM model is based on slicing the domain of interest (a part of the world) to reveal data leakage. The bank case study concentrates on leakage during internal operations of the bank. The leakage spots are exposed through surveying data territory throughout the bank. All streams of information flow are identified, thus points of possible leakage can be traced with appropriate evidence. The modeling of flow may uncover possible hidden points of leakage and provide a base for a comprehensive information flow policy. We conclude that a TM based on the Heideggerian notion of thinging can serve as a foundation for early stages of software development and as an alternative approach to the dominant object-orientation paradigm.

Optic nerve head problem

A 68-year-old woman with a recent history of blurring in the left eye had undergone mastectomy for breast cancer 20 years ago. A series of bone metastases started 5 years after her diagnosis. Examination of the optic nerve head of the left eye revealed an isolated peripapillary mass. Indocyanine green angiography displayed vessels within the mass, and fluorescein angiography demonstrated hyperfluorescence of the mass from vascular leakage plus lobular spots of blocked fluorescence. B-scan ultrasound revealed a hyperechoic-elevated nodular mass on the optic disc. Spectral-domain optical coherence tomography displayed a mass of spherules. Magnetic resonance imaging of the brain demonstrated metastatic tumors. She was diagnosed with an optic disk metastasis from her breast carcinoma.