Improved electrical properties of micro light-emitting diode displays by ion implantation technology

Generally, the inductively coupled plasma-reactive ion etching (ICP-RIE) mesa technology was used to remove p-GaN/MQWs and expose n-GaN for electrical contact in a fabricated micro light-emitting diode (μLED). In this process, the exposed sidewalls were significantly damaged which result in small-sized μLED presenting a strong size-dependent influence. Lower emission intensity was observed in the μLED chip, which can be attributed to the effect of sidewall defect during etch processing. To reduce the non-radiative recombination, the ion implantation using an As⁺ source to substitute the ICP-RIE mesa process was introduced in this study. The ion implantation technology was used to isolate each chip to achieve the mesa process in the μLED fabrication. Finally, the As⁺ implant energy was optimized at 40 keV, which exhibited excellent current-voltage characteristics, including low forward voltage (3.2 V @1 mA) and low leakage current (10^-9 A@- 5 V) of InGaN blue μLEDs. The gradual multi-energy implantation process from 10 to 40 keV can further improve the electrical properties (3.1 V @1 mA) of μLEDs, and the leakage current was also maintained at 10^-9 A@- 5 V.

[Multicenter retrospective study of 38 cases with fumarate hydratase deficiency uterine leiomyoma]

Objective: To investigate the clinicopathological features of fumarate hydratase (FH) deficiency uterine leiomyoma. Methods: The data of 38 patients with FH deficiency uterine leiomyoma were screened and analyzed. The expressions of FH, S-(2-succino)-cysteine (2SC), desmin, p16, p53, CD₁₀ and cell proliferation associated nuclear antigen (Ki-67) proteins were detected by immunohistochemistry, and their clinicopathological features were analyzed retrospectively. Results: (1) Clinical features: the median age of the patients was (42.5±7.4) years old. Twenty-one cases (55%) of them were myomas found in physical examination, and the median maximum diameter of the tumor was 6.0 cm (range: 5.0-7.5 cm); myomectomy was performed in 23 cases (61%), total hysterectomy with or without bilateral appendages in 15 cases (39%); laparoscopic surgery in 27 cases (71%), open surgery in 11 cases (29%); none of the patients had renal cell carcinoma. (2) Histological features: atypical nuclear cells were distributed locally or diffusely, eosinophilic nucleoli and intranuclear inclusion bodies could be seen, glass like globules could be seen in the cytoplasm, nuclear division was 0-4/10 high power field (HPF), and antler like blood vessels and pulmonary edema-like changes could be seen in the stroma. Among 38 patients with FH deficiency uterine leiomyoma, FH was negative in 37 cases (97%), and positive in 1 case (3%); 2SC, desmin, p16, p53, CD₁₀ and Ki-67 showed focal positive expression in 38 cases (100%), including 35 cases (92%) with Ki-67 index<10% and 3 cases (8%) with Ki-67 index ≥10%. (3) Follow-up: 4 cases (11%) recurred, and there was no death. There were significant differences in age, family history, distribution of atypical nuclei and mitosis number between recurrent group and non-recurrent group (all P<0.05). Conclusions: FH deficiency uterine leiomyoma is a rare tumor, which needs pathological examination,immunohistochemical examination and clinical history. Patients younger than 43 years old, with family history, histologically atypical diffuse nuclear distribution and mitotic number ≥3/10 HPF should be alert to the risk of recurrence.

Impedance matching system using triple liquid stub tuners for high-power ion cyclotron resonance heating in EAST tokamak

Ion cyclotron resonance heating (ICRH), one of the main auxiliary methods, for high-power and long-pulse plasma heating had been developed in Experimental Advanced Superconducting Tokamak (EAST). An impedance matching system, one important part of ICRH, had been developed for high-power injection and transmitter protection by reducing the reflected power from the antenna. The input impedance in the outlet of the stub tuner can be measured by voltage-current probes installed on the coaxial transmission line between the antenna and triple liquid stub tuners, and the optimum liquid levels in the stub tuners can be calculated based on the input impedance. The calculation and adjustment process of the optimum liquid levels are described comprehensively in this article. Finally, impedance matching had been achieved between two shots during EAST experiments. In the near future, a real-time impedance matching system will be developed to prevent large variations of the ICRH antenna impedance and achieve steady-state and long-pulse operation with the ICRH system.

Titanium carbide sheet: metallic 2D structure with intrinsic and high catalytic activity for the hydrogen evolution reaction

Searching for a metallic material that possesses intrinsic and high catalytic activity is interesting for the hydrogen evolution reaction (HER) in the electrochemical reduction of water. In this work, via density functional theory, we identified a promising two-dimensional (2D) catalyst material, namely TiC (1 0 0) sheet, which is composed of two atomic layers. Phonon spectrum calculation shows that all vibrational modes of the TiC (1 0 0) sheet are real. Even at 1200 K, the geometrical structure of TiC (1 0 0) sheet is still well kept. Interestingly, TiC (1 0 0) sheet is metallic, which means that TiC (1 0 0) sheet can possess high conductivity. Moreover, the Gibbs free energy ([Formula: see text]) of hydrogen on TiC (1 0 0) sheet at a low coverage is about 0.13 eV, which can be further optimized to an ideal value of 0 eV by introducing a strain. Besides, the effect of thickness on its catalytic activity is also assessed. We observed that TiC (1 0 0) sheet with a large thickness is also metallic. Calculated values of [Formula: see text] for four-layered and six-layered TiC (1 0 0) sheets at a moderate coverage can be about  -0.06 and  -0.04 eV, respectively. Our results highlight a new promising 2D catalyst material for the HER in the electrochemical reduction of water.

[The clinical analysis of corneal interface fluid syndrome after Laser lamellar corneal refractive surgery]

Objective: To analysis, the clinical characteristics, refractive changes, and clinical treatment of interface fluid syndrome after laser lamellar corneal refractive surgery. Methods: During Dec. 2010 to Apr. 2016. In total 6 cases(9 eyes), 3 cases were bilateral, 3 cases were unilateral. Five patients were male and 1 was female. The age of the patients ranged from 20 to 29 years was (24.83±4.02) years. Six cases(9 eyes)of IFS were diagnosed at our hospital. The history and complete ophthalmic examination that include Slit-lamp examination, Slit-lamp photography, refraction, corneal thickness measurement, corneal endothelial cell counting, IOP, anterior segment OCT(AS-OCT), exams were recorded. Results: Post-lasik Primary open angle glaucoma was 2 eyes in 1 patient. 1 patient(1 eye)was Posner-Schlossmann Syndrome and 1 patient(1 eye)was iritis after femtosecond laser. Post-small incision lenticule extraction by steroid drops induced elevated IOP were 5 eyes in 3 patients. Slit-lamp exam indicated edematous corneal flap or cap, lamellar haze, interface fluids accumulation. AS-OCT showed obvious interface dark area. The corneal flap or cap thickening and wrinkles, IOP change, diopter myopic shift, Corneal thickening. Conclusions: IFS is a rare but serious complication after Laser lamellar corneal refractive surgery. The main causes are high intraocular pressure and/or dysfunction of corneal endothelium. For patients with high IOP after laser lamellar corneal refractive surgery, follow up should be observed closely. accurate diagnosis by OCT and corneal endothelial cell counting. Early diagnosis, accurate treatment, its prognosis is good. (Chin J Ophthalmol, 2017, 53: 847-854).

[Genomic analysis of Wenzhou virus in rodents from Zhejiang province]

Objective: Arenavirus is a negative single-stranded RNA virus and an important human pathogen, mainly harbored and transmitted by rodents, causing severe diseases, including hemorrhagic fever and encephalitis. Following the discovery of a novel pathogenic arenavirus (Wenzhou virus, WENV), the prevalence of WENV in local small rodents was investigated. Methods: By using RT-PCR, WENV was screened in 48 and 156 rodents sampled from Wenzhou and Longquan, respectively. Results: Consequently, WENV was detected in 5 (10.41%) rodents sampled from Wenzhou. However, no WENV was identified in all the rodents sampled from Longquan. Genetic analysis of complete genome sequences indicated that 4 of 5 virus strains were closely related to the known Wenzhou viruses with high homology. Especially, the L and S segments of Wencheng-Rn-288 strain shared homology of 87.5% and 91.6% with other viruses, respectively. They formed a distinct lineage, suggesting that this strain might be a novel variant of WENV. Conclusions: Our results indicate that WENV has a high prevalence and high genetic diversity among rodents in Wenzhou. As the respiratory disease caused by WENV has been detected in Cambodia, it is necessary to strengthen the surveillance for WENV in China.

[Expression of long non-coding RNA SNHG8 in Epstein-Barr virus-related gastric cancer and clinical outcome]

Objective: To investigate the expression of long non-coding RNA (lncRNA) SNHG8 in EB virus related gastric cancer and their correlation prognosis. Methods: The expression of SNHG8 in 93 gastric cancers and 93 cancer-free controls, matched by age and sex, were determined by real-time PCR. EB virus expression was detected by EBER in situ hybridization. Results: Forty-one gastric cancers were EB virus associated. For all gastric cancers, SNHG8 expression was 14 times higher (P=0.001) than that in non-cancer controls; in the EB virus related gastric cancers, SNHG8 expression was increased 25 times (P<0.05) over EB virus negative gastric cancers. SNHG8 expression level was also significantly associated with TNM staging (P<0.05). Conclusions: SNHG8 may act as a proto-oncogene, participating in gastric carcinogenesis.EB virus infection of gastric mucosa may promote SNHG8 expression.

[Microcystic, elongated and fragmented invasive pattern in endometrial adenocarcinoma: a clinicopathologic analysis of 72 cases]

Objective: To investigate the clinicopathologic features of microcystic, elongated and fragmented (MELF) pattern invasion of endometrial adenocarcinoma. Methods: HE and immunohistochemistry staining method were used to analysis morphologic features and immunophenotype of 72 patients of endometrial adenocarcinoma with MELF pattern invasion, and chi-square test was used to analysis the clinicopathologic features. Results: The mean age of 72 patients was 54 years (40 to 70 years). Thirty-two patients were pre-menopausal and 40 were post-menopausal. According to the FIGO staging system (2014), 32 cases(44.4%)were at stage Ⅰ, 22 cases(30.6%)at stage Ⅱ, 17 cases(23.6%)at stage Ⅲ and 1 case(1.4%) at stage Ⅳ. Microscopically, MELF invasion showed microcystic, elongated slit-like or fragmented glands in myometrium and their lining cells usually were cube or flat, as well as the single or clusters of eosinophilic tumor cells mimicking histocytes. In addition, a fibromyxoid or inflammatory stromal response was often present.Immunohistochemical staining showed that MELF invasion was positive for p16, CA125 and CA19-9, but negative for ER, PR and p53.Compared with non-MELF pattern invasion, significant differences were noted in menopause pausimenia, FIGO stages, deep invasion into myometrium, lymph metastasis, lymphovascular space invasion (LVSL), serum CA125 and CA19-9 in patients with MELF pattern invasion (all P<0.05). Conclusions: MELF pattern invasion of endometrial adenocarcinoma is characterized by advanced FIGO stage, deep myoinvasion, high metastasis rate to lymph node and LVSL. Pathologists should recognize the MELF invasion and evaluate the depth of myometrium of infiltration and LVSL with special attention to the presence of MELF invasion with necessary immunohistochemistry for more accurate pathological diagnosis.

On the uniqueness of endemic equilibria of an HIV/AIDS transmission model for a heterogeneous population

In this paper, we examine an HIV/AIDS transmission model which has been widely used for studying the spread of HIV/AIDS through sexual contact. Some sufficient conditions are obtained for the uniqueness of endemic equilibrium. We also present a two-group model whose no-disease equilibrium is unstable but it has at least three positive endemic equilibria.

Isolation of (-)-gossypol from natural plant

(-)-Gossypol has been isolated from cottonseed of G. barbadense L. Three Gossypium species were studied for the isolation. The study has also revealed a correlation between the optical activity of gossypol isolated and the species of cottonseed used. Gossypol isolated from the species G. barbadense is always found to be levorotatory caused by an excess of (-)-gossypol, whereas that from the species G. hirsutum is always dextrorotatory caused by an excess of (+)-gossypol. Results of most samples (cultivars) showed that optical purity of gossypol isolated from G. barbadense varied from 10-25%, while that from G. hirsutum varied from 10-20%. This is the first report of (-)-gossypol occurring naturally.