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MiRNAs belong to non-coding RNAs that are involved in cancer development. Acting as a mediator, they could regulate the expression level of numerous gens. However, the expression and function of miR-1299 in gastric cancer (GC) are not clear. To explore the role of miR-1299 in the process of GC. We detected the levels of miR-1299 in clinical samples of GC and investigated the role of miR-1299 in the regulation of the GC cells proliferation, apoptosis and metastasis. Luciferase reporter assay was employed to verify the target of miR-1299. Additionally, the proliferation, apoptosis and metastasis of AGS and SGC7901 cells were analyzed after the overexpression of miR-1299. Our study showed the expression of miR-1299 was decreased in GC tissues and cell lines. It indicated that the cell proliferation, migration and invasion was inhibited, while the cell apoptosis was promoted by the over-expressed miR-1299. Also, we found that miR-1299 could directly target the 3′-untranslated region (3′UTR) of ARF6 genes. In addition, rescue assay demonstrated that miR-1299 overexpression promoted the cell apoptosis and inhibited cell growth, which could be attenuated by the overexpression of ARF6. These findings indicate that miR-1299 regulates cell progression in GC by targeting ARF6 genes, and suggest that miR-1299 may be a tumor suppressor in the GC progression.

In this paper, a type of spectroscopic personal radiation detectors (SPRDs) is developed, which can be used for large area early warning of radiation. The detector (about 240 g, 130 mm× 80 mm× 24 mm) enable the measurement of neutron and γ energy spectrum, and it can run for 12 h on battery power. The neutron detection module uses a planar 6Li glass scintillation crystal. The optical conversion and transmission of the scintillator is realized by using a wavelength shifting fiber (WLSF), and the photoelectric signal conversion is realized by using SiPM. The energy resolution of the thermal neutron peak is 15.5%. A better n/γ screening effect is obtained by using the amplitude screening method. The γ detection module uses CsI (Tl) scintillation crystals with SiPM to realize the photoelectric signal conversion with an average energy resolution of 6.3% (@661 keV). The detector has realized communication with Android cell phone through Bluetooth communication, and radiation monitoring software has been developed on the Android to transmit real-time monitoring data to the server for analysis and early warning, which realize large area abnormal radiation warning.

Background: Different pathological subtypes of lung adenocarcinoma lead to different treatment decisions and prognoses, and it is clinically important to distinguish invasive lung adenocarcinoma from preinvasive adenocarcinoma (adenocarcinoma in situ and minimally invasive adenocarcinoma). This study aims to investigate the performance of the deep learning approach on the classification of tumor invasiveness and compare it with the performances of currently available approaches.Methods: In this study, we propose a deep learning approach based on 3D conventional networks to automatically predict the invasiveness of pulmonary nodules. A total of 901 early-stage non-small cell lung cancer patients who underwent surgical treatment at Shanghai Chest Hospital between November 2015 and March 2017 were retrospectively included and randomly assigned to a training set (n=814) or testing set 1 (n=87). We subsequently included 116 patients who underwent surgical treatment and intraoperative frozen section between April 2019 and January 2020 to form testing set 2. We compared the performance of our deep learning approach in predicting tumor invasiveness with that of intraoperative frozen section analysis and human experts (radiologists and surgeons).Results: The deep learning approach yielded an area under the receiver operating characteristic curve (AUC) of 0.946 for distinguishing preinvasive adenocarcinoma from invasive lung adenocarcinoma in testing set 1, which is significantly higher than the AUCs of human experts (P0.05) and junior thoracic surgeons (0.768, P>0.05).Conclusions: We developed a deep learning approach that achieved comparable performance to intraoperative frozen section analysis in determining tumor invasiveness. The proposed method may contribute to clinical decisions related to the extent of surgical resection.

This paper presented a mobile CsI gamma detector developed to solve the problem of radioactive source detection in a wide area. The performance of the detector was illustrated during the spectra collection investigation. 1-s spectrum collected by the detector was low-count signal, which is hard to distinguish whether it is a source contained signal or not. A rapid detection method of radioactive source based on the low-count gamma spectra was proposed. Principal component analysis (PCA) was the key technology which was able to extract the source information efficiently. The proposed method improved the detector sensitivity and accuracy.

BackgroundCD8+ T cells work as a key effector of adaptive immunity and are closely associated with immune response for killing tumor cells. It is crucial to understand the role of tumor-infiltrating CD8+ T cells in uveal melanoma (UM) to predict the prognosis and response to immunotherapy.Materials and MethodsSingle-cell transcriptomes of UM with immune-related genes were combined to screen the CD8+ T-cell-associated immune-related genes (CDIRGs) for subsequent analysis. Next, a prognostic gene signature referred to tumor-infiltrating CD8+ T cells was constructed and validated in several UM bulk RNA sequencing datasets. The risk score of UM patients was calculated and classified into high- or low-risk subgroup. The prognostic value of risk score was estimated by using multivariate Cox analysis and Kaplan–Meier survival analysis. Moreover, the potential ability of gene signature for predicting immunotherapy response was further explored.ResultsIn total, 202 CDIRGs were screened out from the single-cell RNA sequencing of GSE139829. Next, a gene signature containing three CDIRGs (IFNGR1, ANXA6, and TANK) was identified, which was considered as an independent prognostic indicator to robustly predict overall survival (OS) and metastasis-free survival (MFS) of UM. In addition, the UM patients were classified into high- and low-risk subgroups with different clinical characteristics, distinct CD8+ T-cell immune infiltration, and immunotherapy response. Gene set enrichment analysis (GSEA) showed that immune pathways such as allograft rejection, inflammatory response, interferon alpha and gamma response, and antigen processing and presentation were all positively activated in low-risk phenotype.ConclusionOur work gives an inspiration to explain the limited response for the current immune checkpoint inhibitors to UM. Besides, we constructed a novel gene signature to predict prognosis and immunotherapy responses, which may be regarded as a promising therapeutic target.

This study demonstrates quick and efficient removal of different dyes from wastewater by using MoS2/CuS nanosheet composites (NCs) as adsorbent. The MoS2/CuS NCs are prepared by a facile hydrothermal route, and the composites exhibit high adsorption capacity with 273.23, 432.68, 98.78, and 211.18 mg/g for rhodamine B (RhB), methylene blue (MB), methyl orange (MO), and rhodamine 6G dyes (RhB 6G), respectively. This is ascribed to its high specific surface area (106.27 m2/g) and small mesopores (2.299 nm) which provide numerous adsorption sites and uniform coverage for dye molecules. High adsorption efficiency is obtained for RhB (93.8%), MB (100%), and RhB 6G (84.73%), except for MO (48.9%) at the adsorption equilibrium time at the solution concentration of 80 mg/L. The adsorption of MoS2/CuS NCs can be well described by the pseudo-second-order kinetic model, and the adsorption isotherm at the equilibrium fits well with the Langmuir model. The rapid and efficient adsorption ensures MoS2/CuS NCs to be a bro...

To investigate whether the presence of micropapillary and solid patterns are associated with nodal upstaging and survival patterns in patients with cT1N0M0 lung adenocarcinoma. We retrospectively analyzed the clinicopathologic data of 2571 patients undergoing lobectomy and lymph node dissection or sampling. Logistic and Cox regression analysis were applied to determine the association between histological patterns and nodal upstaging and survival. Nodal upstaging was detected in 115 patients (4.5%) through postoperative pathologic examination. Tumors absent of lepidic pattern, and present with acinar, micropapillary and solid patterns had significantly higher nodal upstaging rate (all P

Small molecule tyrosine kinase inhibitors (TKIs) have transformed the management of advanced non-small-cell lung cancer (NSCLC) harboring activating epithelial growth factor receptor (EGFR) mutations, while the efficacy of TKIs in the adjuvant setting remains unclear. We collected the data of 209 EGFR-mutant NSCLC patients receiving complete resection from 2010 to 2013. Study end points were disease-free survival (DFS) and overall survival (OS). Among the eligible patients, 41 (19.6%) received EGFR TKIs in the adjuvant treatment. The 3-year DFS of adjuvant EGFR TKIs treatment group (70.5%, 95% CI, 54.6–86.4%) was significantly superior that control group (50.2%, 95% CI, 40–60.4%; log-rank P = 0.014). TKIs treatment (HR, 0.51; 95% CI, 0.29–0.97; P = 0.04) was significantly associated with improved DFS in multivariate Cox analysis. No significant difference was observed in 3-year OS between two groups (73.1% [58.0–88.2%] vs 61.8% [52.2–71.4%], log-rank P = 0.21). Propensity-score matching further confirmed that adjuvant TKIs treatment extended the DFS (log-rank P = 0.024), but did not improve OS (log-rank P = 0.40). Our analysis revealed that adjuvant EGFR TKIs treatment was beneficial for early-stage NSCLC patients harboring activating EGFR mutations after complete resection.

Perovskite-type AlFeO3 powders are synthesized by a modified polyacrylamide gel route using different chelating agents at different pHs. X-ray diffraction and Raman results indicate that the AlFeO3 powders synthesized with oxalic acid are rhombohedral structure, while the AlFeO3 powders fabricated by using the other chelating agents exhibit an orthorhombic structure. The scanning electron microscopic images indicate that the morphology of the AlFeO3 samples depend on the choice of chelating agent and pH value. In addition, the particle size of samples with rhombohedral structure is larger than that of the samples with orthorhombic structure. X-ray photoelectron spectroscopy and scanning electron microscopic analysis indicate that the AlFeO3 powders fabricated at pH = 7 have good phase purity and uniform size. Photocatalytic activities of the AlFeO3 samples are determined by the degradation of rhodamine B dye in the presence of hydrogen peroxide and the results show that the samples will probably be applicable in the development of highly efficient photocatalyst. In addition, the rhombohedral AlFeO3 samples exhibit better photocatalysis than the orthorhombic samples, which is probably because that the crystal structure of AlFeO3 samples play a more important role than particle size in photocatalytic activity. The as-prepared AlFeO3 photocatalyst exhibits a pronounced photocatalytic activity for the decomposition of rhodamine B under visible-light irradiation, which is expected to widen the potential applications for perovskite-type oxide AlFeO3. A novel perovskite-type photocatalyst AlFeO3 is synthesized by a modified polyacrylamide gel route using different chelating agents. The crystal structure of AlFeO3 sample depend on the choice of chelating agent and AlFeO3 photocatalyst, in the presence of hydrogen peroxide, exhibit a pronounced photocatalytic activity for the decomposition of rhodamine B under simulated sunlight.

Background The evaluation of the eighth edition of ypTNM staging system for patients with esophageal cancer was limited in the setting of neoadjuvant therapy. Methods A total of 2324 patients with esophageal cancer receiving radio(chemo)therapy prior to surgery from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2013 were eligible for the analysis. Kaplan‐Meier method and Cox proportional hazards models were used to estimate overall survivals. Results Among patients with preoperative therapy, both the seventh edition TNM grouping and the eighth edition ypTNM grouping could significantly stratify the overall survival (both log‐rank P, Analysis of the national SEER database revealed that lymph node status (ypN category) was an important prognostic factor, and supported the combination of ypT1 and ypT2 in grouping. Tumor grade ramained an independent predictor of survival in the setting of neoadjuvant therapy, and could improve the performance of ypTNM staging system.

Background Patients of coronary artery disease (CAD) with type 2 diabetes mellitus (DM2) show increased mortality risk than CAD patients without DM2, while few biomarkers can be used to discriminate them. Methods Fifty‐nine patients of CAD with DM2 (DM2‐CAD group), 79 patients of CAD without DM2 (CAD group), and 63 healthy control subjects were recruited. Circulating miR‐130 (miR‐130a and miR‐130b) and PPAR‐γ (peroxisome proliferator‐activated receptor gamma) were measured and their Pearson correlation was analyzed. 3′ UTR binding prediction and luciferase assay were used to determine the target relationship between miR‐130 and PPAR‐γ. Receiver operating characteristics (ROC) analysis was performed to test the discrimination ability of miR‐130 between DM2‐CAD and CAD groups. Results miR‐130a and miR‐130b showed decreased expression in DM2‐CAD group when compared with the CAD group and health control. Both bioinformatics and luciferase assays showed that miR‐130 could bind the 3′ UTR of PPAR‐γ. Furthermore, miR‐130 negatively correlated with PPAR‐γ in both CAD and DM2‐CAD group in Pearson's coefficient analysis. Both miR‐130a and miR‐130b were able to discriminate DM2‐CAD group from CAD group and control subjects. Conclusion Circulating miR‐130 may regulate the expression of PPAR‐γ and can be used as a biomarker to discriminate DM2‐CAD from CAD.

The electronic and magnetic properties of C-doped α-Al2O3 have been investigated using density functional theory calculations. It is found that magnetism can be induced by doping C at Al and O sites, in which the spin densities are mainly located on the C dopant. Doping C at the Al-site leads to band gap narrowing and greatly modifies the upper valance band, while doping C at the O-site affects the band edges of α-Al2O3 slightly. Based on the dipole selection rules, we have also assigned the sub-band electron transitions in both α-Al2O3:CAl and α-Al2O3:CO.

Background A previous meta-analysis of our research team suggested survival advantage from epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) after surgery in patients with EGFR-mutant non-small cell lung cancer (NSCLC). This study aims to follow up on the findings of the previous one and presents our latest updates through the past few years. Methods The study advanced the previous meta-analysis and included a comprehensive range of relevant studies in PubMed. Disease-free survival (DFS) with hazard ratios (HRs) was calculated using random and/or fixed-effects models. Subgroup analysis and meta-regression analysis were also performed. Results A total of 2,223 patients in seven studies were eligible for the analysis. Adjuvant EGFR-TKIs administration was significantly associated with superior DFS [HR, 0.60; 95% confidence interval (CI), 0.42-0.87], corresponding to an absolute benefit of 3.4% at 3 years, yet with significant heterogeneity (I2=80.0%, P

The Yes‑associated protein (YAP) transcriptional coactivator is recognized as a crucial regulator of human cancer. However, its involvement in human non‑small cell lung cancer (NSCLC) in response to physical cues remains unclear. In this study, substrates with different rigidity were generated in order to evaluate the role of YAP, and its upstream regulators in the Hippo pathway, in the regulation of growth of an NSCLC cell line within particular environments. It was shown that the expression of the YAP protein in SPCA-1 NSCLC cells was significantly increased when cultured on a stiff substrate compared to a soft substrate. However, the expression of phospho‑YAP protein and large tumor suppressor kinase 1 (LATS1) were markedly decreased after culturing on the stiff substrate. Phosphorylation of YAP by LATS1 leads to cytoplasmic retention of YAP, which inhibits its function as a nuclear transcription coactivator. The study also found that the stiff substrate promoted the growth of NSCLC cells in vitro, and an increase in the transcription levels of Survivin, connective tissue growth factor, amphiregulin and Ki67, as well as a decrease in the expression level of YAP in the cytoplasm, and adecrease in p-YAP. In conclusion, the findings showed that the stiffness of the subcellular matrix altered the behavior of NSCLC cells, and that YAP regulated the growth of NSCLC cells in response to matrix stiffness, thereby suggesting a role for the Hippo‑YAP pathway in the response of NSCLC cell growth to specific microenvironments.

This study aimed to exploit the potential therapeutic value of palmatine in treatment of cardiac hypertrophy and the underlying molecular mechanism. Rat hypertrophy model was established by intraperitoneal isoproterenol (ISO) injection. The hypertrophy was evaluated with cardiac hypertrophic parameters, hemodynamic parameters, lipid profile, and non-specific cardiac markers. The animals were intraperitoneally administrated with either palmatine or vehicle. The relative expressions of ANP, BNP, HDAC2, HDAC5, KLF4, and INPP5F transcripts were determined by real-time polymerase chain reaction (PCR). The relative protein levels of HDAC2, HDAC5, KLF4, and INPP5F were analyzed by immunoblotting. Palmatine treatment significantly attenuated ISO-induced hypertrophy in rats and elicited remarkable repressions in ANP, BNP, and HDAC2 transcriptions but not HDAC5. The downstream effector genes KLF4 and INPP5F were greatly restored in a dose-dependent manner in response to palmatine treatment. Our data demonstrated that palmatine possessed promising therapeutic potential against hypertrophy, which was mediated by modulation of HDAC2-KLF4/INPP5F pathway.

Tissue equivalent proportional counters (TEPCs) are commonly based on the Benjamin type of concept. Initially the electric field is optimized by pulse height measurement methods and only one optimum solution was established at that time. In this paper, the electric field distribution is analyzed and optimized using a three-dimensional finite element method. The calculations show that the characteristics of the radial electric field distribution of this type of counters can be equated to cylindrical counters using a pair of appropriate field shaping electrode. Furthermore, the paper analyzes the axial electric field distribution and the possibility of achieving a uniform electric field along its anode while reducing the size of Benjamin type proportional counter design down to 1/10 of currently feasible values with respect to the thinnest available anode wire diameters.

In this study, an ab initio molecular dynamics method is employed to investigate the response behavior of α-Al2O3 to low energy irradiation. Different from the previous experiments, our calculations reveal that the displacements of oxygen dominate under electron irradiation and the created defects are mainly oxygen vacancy and interstitial. The experimental observation of the absorption peaks appearing at 203, 233 and 256 nm for α-Al2O3 under electron irradiations should be contributed by the oxygen defects and these defects will reduce the transmittance of α-Al2O3, which agrees well with the very recent experiment. This study demonstrates the necessity to reinvestigate the threshold displacement energies of α-Al2O3, and to introduce recombination center for oxygen defects to improve its optical properties and performance under radiation environment.

Background: Unprotected left main coronary artery (ULMCA) disease is associated with high mortality and morbidity. The aim of this study is to investigate the efficacy of percutaneous coronary intervention (PCI) on gender-specific patients with ULMCA in the Chinese population and provide a basis for further treatment of PCI in ULMCA disease. Methods: 173 patients (female, N = 52; male, N = 121; mean age = 61.02 ± 7.95) with ULMCA disease, who underwent PCI between January 2010 and December 2014, were investigated in our study. The mean follow-up time was 23.8 ± 7.3 months. The baseline clinical characteristics, coronary angiography (CAG) and PCI procedures, and in-hospital and follow-up outcomes of gender-specific patients were evaluated. Results: There were no statistically significant differences in baseline clinical characteristics with the exception of body weight, height, and smoking indexes between women and men. During PCI procedure, femoral artery puncture was more preferred in women than men (P < .05), whereas radial artery puncture was more preferred in men than women (P < .05). The characteristics of CAG and PCI procedures (except puncture path) were showed with no markedly difference between women and men. The incidences of MACCEs in male patients during the in-hospital and follow-up periods were slightly higher than those of the female patients although with no statistical differences. Conclusion: In northern China, the incidence of ULMCA disease in men is likely to be higher than in women, whereas PCI for ULMCA disease shows similarly favorable outcomes in women as well as in men. During the PCI procedure, femoral artery puncture in women and radial artery puncture in men are recommended.

α-alumina–carbon composites were synthesized and characterized by X-ray powder diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and fluorescence spectrophotometry. The results indicate that the sample morphology depends on the choice of chelating agent. Photoluminescence spectra show that a major emission band around 420 nm and two weaker side bands located around 440 and 470 nm are observed when the excitation wavelength is 360 nm. Interestingly, the intensity of emission peak located at 420 nm decreases with the increase in calcination temperature. But quite on the contrary, the emission intensity at 420 nm increases with the increase of full width at half-maximum of X-ray powder diffraction lines. The carbon doping improved the luminescence properties of α-alumina and did not change the rhombohedral structure of the host. The carbon dopant also improved the surface morphology. The highest luminescence intensity was observed for a composition of 0.4C/0.6 α-Al 2 O 3 . The as-prepared alumina – carbon composites exhibit a pronounced blue light emission when the excitation wavelength is 360 nm, which is expected to widen the potential applications for blue light-emitting materials.

OBJECTIVE Coronary artery perforation (CAP) is a rare, serious complication of percutaneous coronary intervention (PCI). Many studies have addressed the incidence, risk factors, and management of CAP in different countries except China. The aim of this study is to determine the risk factors and types of treatment for coronary perforation occurring in patients undergoing PCI and living in the Cangzhou Chinese population. METHODS AND RESULTS A retrospective cohort of 12,113 patients who underwent PCI was used: 64 patients with CAP and 192 case-control patients were evaluated. Clinical data and findings from coronary arteriography and PCI were analysed. Logistic regression was used to evaluate candidate risk factors for CAP. The treatments were also evaluated. The incidence of CAP in patients undergoing PCI was 0.53%, and the mortality was 7.8% (5/64). Risk factors included female gender, hypertension, non-ST-elevation acute coronary syndrome (NSTE-ACS), right coronary artery (RCA) lesion, calcified lesion, and chronic total occlusion (CTO) (all P 1). CTO had the highest risk (OR = 5.077, P < 0.001). Patients with class I CAP underwent conservative treatment. Patients with class II CAP underwent conservative treatment or low-pressure balloon dilatation (61.1% and 22.2%, respectively). Patients with class III CAP underwent low-pressure balloon dilatation, coated-stent implantation, and emergency surgery (40.9%, 27.3%, and 22.7%, respectively). CONCLUSIONS CAP risk factors in Cangzhou Chinese patients undergoing PCI included CTO, NSTE-ACS, hypertension, calcified and RCA lesions, and female gender. Different treatment methods should be used according to the different classes of CAP.

The energy deposition for low-energy electron beam on Si-SiO2 models was calculated by Monte-Carlo method. Making use of electron paramagnetic resonance (EPR) technique, an investigation of the effect of dopant type and concentration on EPR signal variations was carried out by using p-type and n-type silicon(111) wafers with concentration of 1×1015 cm−3 and 1×1017 cm−3, and the changes of intensity of defect paramagnetic centers before and after irradiation of electrons were compared. The chemical states of Si-SiO2 structure were determined by X-ray photoelectrons spectroscopy(XPS). The results clearly indicate that the effects of dopant variations (type and concentration) are of obvious difference. Compared with p-type silicon, n-type silicon, especially with higher dopant concentration, tends to produce defect at the interface under low-energy electron irradiation with certain flux, which arises from the hole trapped on a nonbridging oxygen atom bonded to P. It is represented in the form of distinct changes of POHC intensity and P2P spectrum. According to the theoretical and experimental data, the relationship among electron energy deposition, chemical states of element Si at SiO2-Si(111) interface, and radiation effect were analyzed and discussed.

This paper reports the development of solar-blind aluminum gallium nitride (AlGaN) 128x128 UV Focal Plane Arrays (FPAs). The back-illuminated hybrid FPA architecture consists of an 128x128 back-illuminated AlGaN PIN detector array that is bump-mounted to a matching 128x128 silicon CMOS readout integrated circuit (ROIC) chip. The 128x128 p-i-n photodiode arrays with cuton and cutoff wavelengths of 233 and 258 nm, with a sharp reduction in response to UVB (280-320 nm) light. Several examples of solar-blind images are provided. This solar-blind band FPA has much better application prospect.

To compare vision quality following phacoemulsification cataract extraction and implantation of a Big Bag or Akreos Adapt intraocular lens (IOL) in patients diagnosed with high myopia complicated with cataract.This was a randomized prospective control study. The patients with high myopia. complicated with cataract, with axial length ≥ 28 mm, and corneal astigmatism ≤ 1D were enrolled and randomly divided into the Big Bag and Akreos Adapt IOL groups. All patients underwent phacoemulsification cataract extraction and lens implantation. At 3 months after surgery, intraocular high-order aberration was measured by a Tracey-iTrace wavefront aberrometer at a pupil diameter of 5 mm in an absolutely dark room and statistically compared between two groups. The images of the anterior segment of eyes were photographed with a Scheimpflug camera using Penta-cam three-dimensional anterior segment analyzer. The tilt and decentration of the IOL were calculated by Image-pro plus 6.0 imaging analysis software and statistically compared between two groups.In total, 127 patients (127 eyes), including 52 males and 75 females, were enrolled in this study. The total high-order aberration and coma in the Akreos Adapt group (59 eyes) were significantly higher compared with those in the Big Bag (P0.05). The clover and spherical aberration did not differ between the two groups (P0.05). The horizontal and vertical decentration were significantly smaller in the Big Bag lens group than in the Akreos Adapt group (both P0.05), whereas the tilt of IOL did not significantly differ between the two groups (P0.05).Both Big Bag and Akreos Adapt IOLs possess relatively good intraocular stability implanted in patients with high myopia. Compared with the Akreos Adapt IOL, the Big Bag IOL presents with smaller intraocular high-order aberration. Coma is the major difference between the two groups.

FPGA(Field-programmable gate array) is programmable device, characterized by high speed and reconfiguration. We could test the circuit programmed by HDL (Hardware Description Language). By observing results of simulations through ModelSim, developers could fix logic errors. Also, they could analyze performance of circuits by the results. In the system, we build the Gigabit Ethernet development platform based on a FPGA. This paper presents the technique of FPGA and Gigabit Ethernet, as well as relevant techniques. On the basis of merits and drawbacks of different design proposals and real demands, we take the EP3C10E144C8N chip belonging to the series of Cyclone III produced by Altera corp. as main controller chip. By the use of an AX88180 MAC chip produced by ASIX Electronics Corporation and a RTL8211E physical chip by Realtek Semiconductor Corporation, we build the development platform. At the receiving end, we capture data frames from the network adapter by winpcap programming and throw video data in the buffer. Considering large amounts of data in the real-time transportation, we design fixed-length queue as the primary structures for buffer. Size of a buffer unit is 32KB, which means that 32 packets can fill the buffer. When the buffer is full, we put the buffer unit to the end of the queue. We get data from buffer and hand it over to application process to display and store video data. When packet loss is detected by the system, log file will record it and thus we can check how many packets lose. The simulations by Quartus II and practical application proves that the system is stable, featuring high speed and low cost. It can be used in various high speed real-time transmission with little modification.

Noise pollution is often introduced during image data acquisition and transmission process. Oversampling technology and algorithm used to improved moving average are applied to reduce noise in UV image project. Both theoretical analysis and Matlab simulations results show that this technology is effective. Considering a virtual signal consisting of Gaussian noise, the new algorithm make the signal’s mean square error (MSE) reduces from 0.01 to 0.0038, which are better than traditional algorithm.

The ratio of optical pulse numbers to corona current (ROPC) is proposed to study the correlation between UV radiation intensity and current strength during AC corona discharge. It’s found that the ROPC curves rose rapidly before a critical voltage and then the curves flatten with the supplied voltage rising, even if the voltage is increased approximately 1 fold higher than the critical voltage. Finally, according to ROPC curves, a new method of determining the voltage for corona inception is introduced, and a novel quantitative analysis method is put forward to judge the level of corona discharge by the means of optical measurement.

Two types of readout integrated circuit named SFD and CTIA are proposed to match the PVDF pyroelectric IR detector. By employing macro model and analyzing the parameters of detector, the best matching conditions including the input reference noise, input impedance, input capacitance, and working point are investigated in details. Based on the property of the AC output for PVDF detector, we propose a novel readout method, with which the ratio of signal to noise can be greatly improved. Furthermore, the linearity and sensitivity for both circuits are discussed by the means of Spectre tools.

In this paper, specific issues in designing an avalanche photodiode (APD)-based non-line-of-sight (NLOS) ultraviolet (UV) communication system are investigated. A proper wavelength of the UV LEDs and a system configuration should be considered carefully to assure the feasibility of this system. Using the single scattering model, the received optical power at the sensitive area of the APD can be calculated. According to the calculation, it revealed that the scattered ultraviolet signal level was very low; therefore, a post signal processing circuit was necessary. The authors put forward the key components of the circuit based on the compromise between signal bandwidth and gain. The performance of this circuit was evaluated by means of software simulation, and continued work was involved to improve its signal noise ratio (SNR). The transmitter used in this system was 365 nm UV LED array. Strictly speaking, this was not the practical outdoor UV communication system. Since the scattering coefficient of 365 nm UV only drops a little compared with solar blind UV, the research-grade UV communication could be carried out in a darkroom without a great influence. By combining an APD with a compound parabolic concentrator (CPC) optical system, the effective collection area and field of view (FOV) of the detector could be adjusted. Several issues were also raised to improve the performance of UV communication system, including using more powerful UV LEDs and choosing suitable modulation schemes.

Recently, AlGaN-based material and related devices have been investigated intensiv ely because of their applications in ultraviolet solar-blind detectors, blue light-emitting diodes, UV laser diodes, and high-power-temperature devices. Due to intrinsic difficulty to grow high aluminum fraction material, achieving reasonable good quality of wafers is the key aspect to fabricate high performance solar-blind AlGaN-based detectors. Transmission spectra, XRD, and a two dimension transmission scanning system were employed to evaluate the properties of AlGaN-based material. Wet chemical etching process of n-type AlGaN in 20% aqueous KOH solutions was performed to reduce dry etching damages and the average leakage current. I-V characterization indicated that the average leakage current of the wet etching treated detectors was lower than that of the detectors without treatment by about one order of magnitude. Ti/Al/Ti/Au contact on n-type Al 0.63 Ga 0.37 N was optimized to get a low series resistance. 128 ™ 128 solar-blind AlGaN UV Focal Plane Arrays (FPAs) we re fabricated and the performance were char acterized. A CTIA (capacitive-transimpedance) readout circuit architecture has been pr oven to be well suited for AlGaN detect ors arrays. The results show that 128 ™ 128 back-illuminated AlGaN PIN detector SNR is as high as 74 db at a speed of above 30 frames per second. Keywords: Al

Thermal oxidation interfacial layer was inserted into the GaN-based material and Schottky contact interface during the device preparation to increase the barrier height. Different thickness of thermal oxidation interfacial layer was created by keeping the chips in the Rapid Thermal Processor (RTP) in atmosphere ambient for different periods of time before evaporating transparent Schottky contact. For GaN Schottky diodes, as the time kept in RTP increases, the diodes' zero-bias resistances decrease and the dark current increase considerably, and the peak photoresponse and UV-visible rejection factor of the responsivity of the diodes decrease abruptly. For Al 0.45 Ga 0.55 N Schottky diodes, as the time increase, the diodes' zero-bias resistances and dark current increase slightly, while the peak photoresponse and the UV/visible rejection factor of the responsivity of the diodes decrease a little.

GaN-based avalanche photodiodes (APDs) have become of increased interest in the UV detection arenas. However, numerous material-, fabrication-, and design-related problems are exactly settled before GaN-based APDs can be commercialized. In this study, we, first, discussed recent development of the GaN-based APDs. Then front- and back-illumination (respectively realizing electron and hole initial impact-ionization) p-i-n heterostructure devices with various mesa diameters were fabricated. The device with a diameter of 40 μm exhibited a multiplication gain of ~680, at reverse bias of ~76 V corresponding to the magnitude of the electric field of ~ 3 MV/cm by experiment indicating and simulation verifying. To confirm the origin of dark current under different reverse bias, the dark current-voltage characteristic of various sized mesa devices were performed. The dark current could be linearly fitted to the device diameter (or circumference) implied that the surface leakage along the mesa sidewall was the dominant component of the dark current. At zero bias, the spectral peak responsivity reached ~ 0.14A/W for front illumination, and ~ 0.152A/W for back illumination at a wavelength of 358 nm. The positive breakdown voltage coefficient from the temperature-dependent current-voltage characteristics was 0.02 V/K.

This paper presents a low-power low-noise wide-dynamic-range GaN-based UV detector with pixel-level A/D conversion. The detector comprised an array of 50×50 m 2 pixels with a multi-channel bit serial (MCBS) ADC in each pixel. Each pixel contains a UV photo-detector, a 1-bit comparator and a 3-T memory cell. The A/D conversion is performed simultaneously for all pixels. The digital data is read out from the pixel arra y in manner of a random access digital memory. Since there are many ADCs operating simultaneously, power consumption for each ADC must be minimized. To satisfy the low power consumption, A power-down circuit is introduced in. The minimal value for ADC resolution and the frame rate are 10bits and 100f/s respectively. A high GBW comparator is designed to satisfy this demand. In order to suppress the FPN and 1/f noise a digital correlated double sampling (CDS) is adopted in this application. Keywords: GaN-based, CMOS, Pixel level ADC, UV photo-detector, Comparators, Power-Down, CDS

The influence of larger constant current burning was studied and analyses on the failed detectors were given. "1/f" noise is observed in the reign of g-r noise, and the exponential factor had a trend of increasing with burning time. Peak wavelength and cutoff wavelength of the detectors had no apparent change during electrical burning, but there were decreases on the short wavelength side in spectral response. After a long time burning, minority carrier lifetime of the detectors decreased as well as black-body signals. Analyses showed that defects increased at the surface of detectors after burning, which was responsible for decreasing the detector performance, even detector failure.