[Enhancing survival outcomes in stage Ⅲ gastric/esophagogastric junction cancer: a retrospective study of immune checkpoint inhibitors and adjuvant chemotherapy based on real-world data]

Objective: To explore the efficacy of immune checkpoint inhibitors combined with adjuvant chemotherapy in patients with phase III gastric cancer and esophagogastric junction cancer. Methods: This study used a retrospective cohort study method based on real-world data. Clinical data of 403 patients with stage III gastric/esophagogastric junction cancer who underwent gastrectomy followed by adjuvant therapy in the Department of Gastric Surgery at Sun Yat-sen University Cancer Center from January 2020 to December 2023 were retrospectively collected. The study cohort comprised 147 (36.5%) patients with stage IIIA, 130 (32.3%) with stage IIIB, and 126 (31.3%) with stage IIIC gastric/esophagogastric junction cancer. Of them, 15 (3.7%) were HER-2 positive, 25 (6.2%) dMMR, and 22 (5.5%) patients Epstein-Barr virus encoding RNA (EBER) positive. Based on treatment plans, the patients were divided into immune checkpoint inhibitor combined with chemotherapy group (immune therapy group, n=110, 71 males and 39 females, median age 59 years old) and chemotherapy alone group (chemotherapy group, n=293, 186 males and 107 females, median age 60 years old). All patients in the immunotherapy group received immune checkpoint inhibitors targeting the programmed cell death protein-1 (PD-1) and its ligand (PD-L1). Of them, 85 received pembrolizumab, 10 received sintilimab, 8 received tislelizumab, 4 received camrelizumab, 2 received toripalimab, and 1 received pabocizumab. The adjuvant chemotherapy regimens used among the chemotherapy alone group includes SOX regimen (132 cases), XELOX (102 cases), S-1 monotherapy (44 cases), and other regimens (15 cases). The 3-year DFS rate of the two groups was compared, and subgroup analysis was conducted based on different ages, molecular phenotypes, pTNM staging, extranodal infiltration, and tumor length. Results: The median follow-up was 20.5 months (range 3.1~46.3), with a 3-year overall DFS rate of 61.4% for the entire 403 patients. The 3-year DFS rate for the immunotherapy group was 82.7%, higher than the chemotherapy alone group (58.8%), with a statistically significant difference (P=0.021). Multivariate analysis showed that postoperative immunotherapy was a protective factor for DFS (HR=0.352, 95%CI: 0.180~0.685). Subgroup analysis showed that stage IIIC (HR=0.416, 95%CI: 0.184~0.940), aged ≥60 years (HR=0.336, 95%CI: 0.121~0.934) and extranodal invasion (HR=0.378, 95%CI: 0.170~0.839) were associated with benefit from the combined immune adjuvant chemotherapy, while no association was observed for MMR, HER-2 or EBER status. Conclusion: Stage III gastric/esophagogastric junction cancer patients may benefite from postoperative immune checkpoint inhibitor combined with adjuvant chemotherapy in real-world settings.

[Arthroscopic assistance of latissimus dorsi tendon transposition for the treatment of unrepairable rotator cuff tear]

OBJECTIVE

To explore clinical effect of arthroscopy-assisted rotator cuff tendon transfer in treating irreparable rotator cuff tears (IRCT).

METHODS

From May 2015 to May 2018, 23 patients with unrepairable rotator cuff tears were treated with arthroscopy-assisted rotator cuff tendon transfer, and 21 patients were followed up finally, including 8 males and 13 females, aged from 48 to 82 years old with an average of(64.3±9.1) years old;the courses of disease ranged from 6 to 36 months with an average of (14.0±6.4) months. American Rotator and Elbow Surgeons Score(ASES) and Constant-Murley score were used to evaluate clinical efficacy before surgery and at the latest follow-up.

RESULTS

All 21 patients were followed up for 36 to 54 months with an average of (39.4±4.4) months. Axillary incision of 1 patient was redness, swelling and exudation after surgery, which healed after 3 weeks of dressing change, and exudate culture was negative. At the latest follow-up, MRI showed partial tearing of the metastatic tendon in 2 patients, but pain and movement of the affected shoulder were still better than before surgery. ASES increased from preoperative (41.0±9.6) scores to the latest follow-up (75.6±14.0) scores, and had statistical difference (t=10.50, P<0.01). Constant-Murley score increased from (49.8±7.1) scores before operation to (67.5±11.6) scores at the latest follow-up (t=11.27, P<0.01).

CONCLUSION

Arthroscopic assisted latissimus dorsalis tendon transposition restores physiological and anatomical structure of glenohumeral joint by reconstructing balance of horizontal and vertical couples of shoulder joint, thus achieving the stability of the shoulder joint, relieving shoulder pain and improving shoulder joint function.

[Analysis of management efficacy in patients with heavy menstrual bleeding associated with antithrombotic therapy]

Objective: To evaluate different methods' efficacy of controlling acute bleeding and managing long-term menstruation in patients with heavy menstrual bleeding (HMB) associated with antithrombotic therapy. Methods: The clinical data of 22 cases with HMB associated with antithrombotic therapy admitted to Peking University People's Hospital from January 2010 to August 2022 were analyzed, aged 39 years old (26-46 years). Changes in menstrual volume, hemoglobin (Hb), and quality of life were collected after control of acute bleeding and long-term menstrual management. Menstrual volume was assessed by pictorial blood assessment chart (PBAC), and quality of life was assessed by menorrhagia multi-attribute scale (MMAS). Results: (1) Treatment of acute bleeding: of the 22 cases with HMB associated with antithrombotic therapy, 16 cases were treated in our hospital and 6 in other hospital for emergency bleeding; of the 16 cases treated in our hospital, 3 underwent emergency intrauterine Foley catheter balloon compression due to severe bleeding (Hb decreased by 20 to 40 g/L within 12 hours). Of the 22 cases with antithrombotic therapy-related HMB, 15 (including 2 cases with severe bleeding) underwent emergency aspiration or endometrial resection, and intraoperative placement of levonorgestrel-releasing intrauterine system (LNG-IUS) followed by a significant reduction in bleeding volume; 3 cases had controlled acute bleeding after rivaroxaban dose reduction and continued observation; 2 cases were given gonadotropin-releasing hormone agonists to control acute bleeding in other hospital, of which 1 case was temporarily treated with periodic blood transfusion, and the other one patient underwent total hysterectomy; and 2 cases had temporary amenorrhea with oral mifepristone after intrauterine balloon compression or oral norethindrone. (2) Long-term menstrual management: of the 22 cases with antithrombotic therapy-related HMB, 15 had LNG-IUS placement and 12 had LNG-IUS placement for 6 months, and menstrual volume was significantly reduced [PBAC scores were 365.0 (272.5-460.0) vs 25.0 (12.5-37.5), respectively; Z=4.593, P<0.001], Hb was significantly increased [91.5 g/L (71.8-108.2 g/L) vs 128.5 g/L (121.2-142.5 g/L); Z=4.695, P<0.001], and quality of life was significantly improved [MMAS scores were 415.0 (327.5-472.5) vs 580.0 (570.0-580.0), respectively; Z=-3.062, P=0.002] before placement compared with 6 months after placement. Three rivaroxaban dose reduction patients' PBAC scores decreased by 20 to 35 but remained >100, and perceived quality of life did not change significantly. Two cases with temporary amenorrhea treated with oral mifepristone felt significantly improved quality of life, and the MMAS scores increased by 220 and 180, respectively. Conclusion: Intrauterine Foley catheter balloon compression, aspiration or endometrial ablation could be used to control acute bleeding in patients with antithrombotic therapy-related HMB, and LNG-IUS for long-term management could reduce menstrual volume, increase hemoglobin, and improve the quality of life of patients.

[The association of posterior tibial slope changes between joint gap contact force and the range of motion in Oxford mobile bearing unicompartmental knee arthroplasty]

Objective: To investigate the correlation between the change of posterior tibial slope (PTS) after unicompartmental knee arthroplasty (UKA) and the contact force at the end stage of knee flexion and extension, as well as the postoperative range of motion. Methods: The data of 38 cases (46 knees) of UKAs undertaken in China-Japan Friendship Hospital from June 2020 to June 2021 were analyzed in this study. A custom-designed force sensor was used to measure gap contact force in the medial gap of UKA. The correlations between each two of the three factors-the change of PTS (∆PTS), the gap contact force of full extension and deep flexion and the range of knee motion were analyzed. Results: Totally of 38 patients (46 knees) were enrolled, including 14 males and 24 females, aged (69.1±7.4) years, with an average follow-up of (11.2±3.7) months. The average gap contact force was (88.3±40.6)N, the adjusted contact force of the full extension gap was 81.7%±33.8%, while that of the deep flexion gap was 55.6%±31.0%. At the last follow-up, the fixed flexion degree[M(Q₁, Q₃)] was 0°(0°, 3°), which was significantly lower than the preoperative value of 0°(0°, 5°) (P<0.05); the postoperative max flexion degree was 115.9°±16.4°, it was increased when compared with the preoperative value of 112.0°±16.8° (P<0.05); and the postoperative PTS was 8.3°±2.7°, and there was no significant difference with the preoperative value (8.6°±2.1°,P>0.05). There was a positive correlation between ∆PTS and both the contact force of full extension gap and the fixed flexion degree (r=0.334 and 0.317, P<0.05). Besides, there was a negative correlation between ∆PTS and the contact force of the deep flexion gap (r=-0.397, P<0.05). However, the correlations between these two factors and the max flexion degree were not significant (P>0.05). Conclusions: The reduction of PTS in UKA would reduce the contact force of the full extension gap, as well as the postoperative fixed flexion deformity. Besides, it could increase the contact force of the deep flexion gap, but would not influence the max flexion degree of the knee postoperatively.

[Whole transcriptome analysis and critical gene regulatory network analysis during Schistosoma japonicum infection and praziquantel treatment in mice]

OBJECTIVE

To investigate long non-coding RNA (lncRNA)-microRNA (miRNA)-messenger RNA (mRNA) interactions and identify the critical gene regulatory network during Schistosoma japonicum infections and praziquantel treatment using whole transcriptome sequencing.

METHODS

A total of 110 male C57BL/6 mice were randomly divided into the control group, the infection group and the treatment group. Mice in the infection treatment and the control group were infected with S. japonicum cercariae via the abdomen, and liver specimens were sampled from 10 mice 3, 6, 8 weeks post-infection. Praziquantel treatment was given to mice in the treatment group 8 weeks post-infection, and liver specimens were sampled from 10 mice 2, 4, 6, 8, 10 weeks post-treatment. Total RNA was isolated from mouse liver specimens, and the transcriptome library was constructed for highthroughput whole transcriptome sequencing. The significant differentially expressed genes were subjected to functional annotations, Gene Ontology (GO) terms enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Correlation analysis of liver specimens was performed using R Corrplot and Himsc functions, and the lncRNAmiRNA-mRNA interaction network analysis was performed using R MixOmics and Himsc functions.

RESULTS

There were 1 176 differentially expressed miRNAs, 5 270 differentially expressed mRNAs, and 2 682 differentially expressed lncRNAs between the infection group and the control group, 1 289 differentially expressed miRNAs, 7 differentially expressed mRNAs, and 69 differentially expressed lncRNAs between the treatment group and the infection group, and 1 210 differentially expressed miRNAs, 4 456 differentially expressed mRNAs, and 2 016 differentially expressed lncRNAs between the treatment group and the control group. Correlation analysis showed a higher correlation of gene expression between the treatment group and the control group. Principal component analysis showed obvious separate clustering between the infection group and the treatment group. The differentially expressed genes with significant relevance were significantly enriched in 24 GO terms, including arachidonic acid metabolic process, xenobiotic catabolic process, unsaturated fatty acid metabolic process, xenobiotic metabolic process, long-chain fatty acid metabolic process, and 8 KEGG metabolic pathways, including cholesterol metabolism, tyrosine metabolism, linoleic acid metabolism, retinol metabolism, and steroid hormone biometabolism.

CONCLUSIONS

There were 23 mRNAs including Cyp2b9 and 14 lncRNAs including Rmrpr in the core position of the gene regulatory network, which may play a critical role in S. japonicum infections and praziquantel treatment, and 9 miRNAs including miR-8105 may serve as potential molecular markers for diagnosis of S. japonicum infections.

CD8αα+T cells exert a pro-inflammatory role in patients with psoriasis

Background

Psoriasis is a common chronic inflammatory disease caused by excessive activation of CD4⁺T cells, including Th17, Th1 and Th22. The role of CD8⁺T cells in psoriasis pathogenesis remains poorly understood.

Aim

To identify the phenotype of CD8⁺T cells in patients with psoriasis and to investigate its role in the formation of lesions.

Methods

The phenotype of CD8⁺T cells in psoriatic lesions was detected by immunofluorescence staining. Flow cytometry was performed to detect their phenotype in peripheral blood. Thereafter, coculture of CD8αα⁺T cells with autogenous CD4⁺T cells was performed to investigate the function of CD8αα⁺T cells in patients with psoriasis. Finally, pro‐inflammatory factors produced by CD8αα⁺T cells were examined by immunofluorescence staining and flow cytometry.

Results

Compared to the CD8αβ⁺T cells, CD8αα⁺T cell infiltration in psoriatic lesions markedly increased. Moreover, epidermal CD8αα⁺T cells exhibited tissue‐resident memory T cells (T_RM) phenotypes and dermal CD8αα⁺T cells exhibited effector memory (T_EM) phenotypes in psoriatic lesions. Additionally, we found that CD8αα⁺T cells from patients with psoriasis did not express the markers of regulatory T cells and could promote the proliferation of CD4⁺T effector cells and produce interleukin‐17 and interferon‐γ.

Conclusions

Our findings demonstrate that CD8αα⁺T cells contribute to the pathogenesis of psoriasis by producing pro‐inflammatory factors.

[Safety analysis of definitive surgery for chronic radiation intestinal injury]

Objective: To investigate the safety of definitive surgery for chronic radiation intestinal injury. Methods: A descriptive case series study was performed. Clinical data of 105 patients who were diagnosed as chronic radiation intestinal injury, had complete data and received definitive surgery (the radiation-induced intestinal segment and digestive tract reconstruction) at Department of Gastrointestinal Surgery of Beijing Tsinghua Changgung Hospital from June 2016 to May 2020 were retrospectively analyzed. There were 30 males (28.6%) and 75 females (71.4%) with the median age of 58 years (P25, P75: 52, 64 years). Patients who had tumor recurrence or refused surgical treatment were excluded. According to the preoperative evaluation and clinical manifestations, to select the resection range. Outcome parameters: (1) preoperative evaluation (nutrition risk assessment and status of obstruction or fistula); (2) clinical manifestations and treatment strategies; (3) details of surgical parameters; (4) postoperative complications, and Clavien-Dindo classification III to V was defined as main moderate-severe complication. Results: (1) Preoperative evaluation: Eighty-eight patients (83.8%) developed symptoms of chronic radiation intestinal injury more than 1 year after the end of radiotherapy. Ninety-eight patients (93.3%) had preoperative NRS-2002 score ≥3, 74 patients (70.5%) received preoperative parenteral nutritional support, and the median time of nutritional support was 10.5 (7.0, 16.0) days. Sixteen patients (15.2%) received small intestinal decompression tube implantation due to severe obstruction. (2) Clinical manifestations and treatment strategies: Among 105 patients, 87 (82.9%) presented with obstruction and received definitive resection of the radiation-induced intestinal segment plus one-stage digestive tract reconstruction; 18 (17.1%) presented with intestinal fistula and all of them received definitive resection of the radiation-induced intestinal segment, intestinal fistula plus one-stage digestive tract reconstruction. Among above 18 patients with fistula, 3 patients with ileorectal stump fistula received pedicled pelvic closure of greater omentum at the same time; 4 patients had ileal vesical fistula, of whom 2 patients received cystectomy and bladder repair due to preoperative nephrostomy decompression, and the other 2 patients received transection of the small intestine proximal and distal to the fistula and anastomosis of the intestinal loop without fistula resection, intestinal fistula or bladder fistula repair. (3) The details of surgical parameters: Median operative time and intraoperative blood loss was 230 (180, 300) minutes and 50 (20, 50) ml respectively. Ninety-two patients (92/105, 87.6%) underwent ileocolonic anastomosis, and anastomosis on the hepatic flexure or splenic flexure colon were performed in 88 (83.8%) and 4 (3.8%) patients respectively. Ileoileal anastomosis was performed in 13 patients (12.4%). The anastomotic site of 92 patients (87.6%) was strictly located in the contralateral quadrant of the radiation field, and the anastomotic site of 13 patients (12.4%) was far from the radiation field. Nine patients (8.6%) had more than one anastomosis, 5 patients (4.8%) had less than 180 cm of residual small intestine, 7 patients (6.7%) underwent retrograde intestinal permutation, 4 patients (3.8%) underwent abdominal wall reconstruction surgery due to abdominal wall defects, and 87 patients (82.9%) had severe abdominal pelvic adhesions (grade 3-4 adhesions). Intraoperative complications occurred in 3 patients (2.9%), which were found in time and handled properly. The median postoperative hospital stay was 13.0 (12.0, 24.5) days, and all the patients had resumed oral feeding upon discharge. (4) Postoperative complications: Fourteen patients (13.3%) had 18 major complications (grade III to V). The incidence of postoperative anastomotic leakage was 5.7% (6/105), and the incidence of anastomotic leakage for ileocolon anastomosis and ileoileal anastomosis was 2.2% (2/92) and 4/13, respectively (χ(2)=17.29, P<0.001). The incidence of postoperative anastomotic leakage of intestinal fistula and intestinal obstruction was 3/18 and 3.4% (3/87), respectively (χ(2)=4.84, P=0.028). The mortality at 30 days after operation was 1.0% (1/105), after abdominal infection and septic shock caused by postoperative anastomotic leakage resulting in multiple organ failure. Conclusion: For chronic radiation intestinal injury patients with obstruction or fistula, definitive surgical treatment is feasible and safe with acceptable major complications.

[Efficacy and safety of Kangbingdu granules in the treatment of influenza: a randomized, double-blind, double-dummy, positive-drug parallel control multicenter clinical trial]

Objective: To observe the efficacy and safety of Kangbingdu granules (KBD) in the treatment of influenza. Methods: A multicenter, randomized, double-blind, double-dummy, and positive-drug parallel control trial was conducted in 27 Grade ⅢA hospitals in China and the subjects were randomly assigned to the KBD test group or the oseltamivir phosphate capsule control group at a ratio of 1∶1. 200 subjects were planned to be enrolled in each group. The experimental group was given KBD (18g each time, 3 times a day) and oseltamivir phosphate simulator orally, while the control group was given oseltamivir phosphate capsule (75 mg each time, twice a day) and KBD simulator orally for 5 days. The primary efficacy indicators included the remission time of major clinical symptoms and the time of complete defervescence. The secondary efficacy indicators included dosage of acetaminophen, the change of traditional Chinese medicine (TCM) syndrome score and the remission time of other important clinical symptoms. The efficacy of KBD in the test group and Oseltamivir phosphate control group were compared. Adverse events or adverse reactions were observed at the same time to evaluate the safety of KBD Granules. Results: A total of 393 subjects from 27 Grade ⅢA hospitals in China were enrolled. The experimental group included 195 subjects and 191 subjects (97.95%) completed the trial, While the control group included 198 subjects and 195 subjects (98.48%) completed the trial. There was no significant difference in the shedding rate and rejection rate between the two groups (P>0.05). In the Full Analysis Set (FAS), the mean age of the experimental group was (34.9±14.4) years old, with 83 males (42.78%). The mean age of the control group was (33.3±13.5) years old, with 78 males (39.59%). There were no statistically significant differences between the two groups in demographic data, physical examination, viral pathogen detection, total score of TCM syndromes and scores of each symptom at baseline (P>0.05). In the FAS, the remission time M (Q₁, Q₃) of major clinical symptoms was 3.0 (3.0, 4.0) days in the experimental group and 3.0 (3.0, 4.0) days in the control group, and the difference was not statistically significant (P>0.05). The time M (Q₁, Q₃) of complete defervescence was 34.0 (20.3, 49.0) hours in the experimental group and 36.5 (19.6, 48.8) hours in the control group, and the difference was not statistically significant (P>0.05). KBD granules had the same effect as Oseltamivir phosphate capsule (P>0.05) in terms of acetaminophen dosage, TCM syndrome effect and disappearance rate of most important clinical symptoms. Meanwhile, the disappearance rate of dizziness and chest distress on day 3 in the KBD granules group was better than that of oseltamivir phosphate capsule (P<0.05). Conclusion: KBD granules have the same efficacy as Oseltamivir Phosphate capsule in the treatment of influenza and the drug safety is good.

[Clinical characteristics and related factors of acute tubular necrosis in patients with minimal change disease]

Objective: To investigate the clinical characteristics and related factors of acute tubular necrosis (ATN) in patients with minimal change disease (MCD). Methods: Patients from Chinese PLA General Hospital who were pathologically diagnosed with MCD and had clinical manifestations of nephrotic syndrome from January 1, 2013 to December 31, 2019 were included. The clinical and pathological data of patients were retrospectively analyzed. Meanwhile, the incidence and clinical characteristics of ATN in different age groups were compared. The risk factors for ATN were assessed using binary logistic regression. Results: A total of 525 patients were included, with a gender ratio of 1.56∶1 (male: female), aged 33 (21, 48) years old. ATN occurred in 49 (9.3%) of 525 patients, of which 34 were male and 15 were female. The incidence of ATN increased with age in MCD patients of different age groups (χ(2)=31.442, P<0.001). The incidence of ATN in groups of age≤20 years, 21-40 years, 41-60 years, and >60 years was 2.4% (3/123), 5.2% (10/192), 13.2% (20/152) and 27.6% (16/58), respectively. Elevations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT) and serum IgE occurred in 92 patients (17.5%), 53 patients (10.1%), 99 patients (18.9%), and 303 patients (57.7%), respectively. There were significant differences in age, ALT, serum creatinine, serum urea nitrogen, history of diabetes and history of hypertension between non-ATN group and ATN group (all P<0.05). The results of logistic regression analysis showed that>40 years old (OR=6.283, 95% CI: 2.695-14.649, P<0.001) and serum albumin (OR=0.924, 95% CI: 0.857-0.997, P=0.040) was independently associated with ATN in MCD patients. Conclusion: Age>40 years is an independent risk factor and serum albumin is a protective factor for ATN in MCD patients.

[Clinical analysis of 30 cases with asbestos-related occupational tumors]

Asbestos is classified as a Class 1 carcinogen by the International Cancer Organization (IARC) , and almost all types of asbestos are carcinogenic. The clinical data of 30 asbestos-induced occupational tumor patients in Qingdao city from January 2002 to May 2019 were analyzed, including 24 cases of asbestos-induced lung cancer and 6 cases of asbestos-induced malignant mesothelioma. Mesothelioma was significantly worse than lung cancer in terms of malignancy, the survival time of patients is shorter, and the mortality rate was higher. Both its diagnostic methods and treatment methods should be improved. The high incidence of asbestos-caused tumors is coming. It is recommended that workers exposed to asbestos dust should undergo regular chest CT examinations for early detection, early diagnosis and early treatment.

[Analysis of positive rate of sinusitis in children with head and pituitary MRI]

Objective: To investigate the incidence of asymptomatic sinusitis in children by magnetic resonance imaging. Method: Collected the head MRI of 1-12 years old children. According to the examination site,the MRI group and the pituitary MRI group (both sinus level) were included.The nasal-sinusitis-like changes in the field were used as positive criteria. Statistical analysis was conducted on the test results. Result: In 3 900 children with MRI, the positive rate of sinusitis was 30.21%. The positive rate increased from 2 years old to 3 years old and remained at the age of 11 years.The higher positive rate was slightly decreased at 12 years old; 1 228 cases of pituitary MRI examination, the positive rate of nasal-sinusitis was 38.27%, the positive rate increased significantly from the age of 2, reached the peak at 6 years old, and then fell back, still kept high positive rate, the lowest to 12 years old. The positive rate of total sinusitis was 32.14%. No obvious difference was found between two groups. Conclusion: Children's skull and pituitary MRI imaging suggests that the positive rate of nasal-innocuous sinusitis is related to age, peaking at 3 to 8 years old, and then gradually decreasing.

[A prospective cohort study on the relationship between maternal prenatal depressive symptoms and children's behavioral problems at 2 years old]

Objective: To explore the associations between maternal and prenatal depressive symptoms and children's behavioral problems at 2 years old. Methods: In the present study, a total of 491 mother-child pairs were selected from the Shanghai-Minhang Birth Cohort Study (S-MBCS) which was conducted in Maternal and Child Health Hospital of Minhang District in Shanghai between April and December, 2012. Data from the Center for Epidemiologic Studies on Depression was gathered to assess the maternal depressive symptoms in the second and third trimester of pregnancy, as well as at 6 months and 12 months postpartum. Neurodevelopment at 2 years was assessed, using the Child Behavior Checklist. We used generalized linear models with a log-link function and a Binomial distribution to estimate the risk ratios (RRs) and 95%CIs, on children's behavioral problems at 2 years of age. Sensitivity analyses were performed among participants without postpartum depressive symptoms. Results: After adjustment on factors as maternal age, gestation week, average monthly income per person, parental education and children's gender etc., maternal depression in second trimester of pregnancy was found associated with higher risk of both developing emotional (RR=2.61, 95%CI: 1.36-4.99) and internalizing problems (RR=1.94, 95%CI: 1.22-3.08). However, maternal depression in third trimester was found to be associated with higher risks of developing emotional (RR=6.46, 95%CI: 3.09-13.53), withdrawn (RR=2.42, 95%CI: 1.16-5.02), aggressive (RR=2.93, 95%CI: 1.45-5.94), internalizing (RR=1.79, 95%CI: 1.01-3.16) or externalizing problems (RR=2.56, 95%CI:1.49-4.42). In sensitivity analysis, antenatal maternal depression was found positively associated with children's emotional, internalizing and externalizing problems and the differences all statistically significant. Conclusions: Maternal depression during pregnancy might increase the risks of children's behavioral problems. In order to decrease the incidence of children's behavioral problems and promoting both maternal and child health status, monitoring program regarding maternal mental health care should be strengthened.

[Atypical computed tomography manifestations of thoracic sarcoidosis]

Objective: This study evaluated the atypical computed tomography (CT) manifestations of thoracic sarcoidosis. Methods: Medical data of 190 patients with thoracic sarcoidosis were retrospectively reviewed. Results: The atypical CT manifestations of thoracic sarcoidosis observed were unilateral hilar lymphadenopathy with or without mediastinal lymphadenopathy(n=12, 6.3%), mediastinal lymphadenopathy without hilar lymphadenopathy(n=9, 4.7%), patchy consolidation (n=23, 12.1%), sarcoid galaxy sign (n=22, 11.6%), reversed halo sign (n=1, 0.5%), and ground-glass opacities (n=52, 27.4%). Air trapping was found in 8 of 10 patients who underwent both inspiratory and expiratory CT. Post-treatment CT scans showed improvements in most patients. Of the 12 patients with unilateral hilar lymphadenopathy with or without mediastinal lymphadenopathy, 10(83.3%) improved. Of the 9 patients with mediastinal lymphadenopathy without hilar lymphadenopathy, 8(88.9%) improved. Of the 23 patients with patchy consolidation, 15(65.2%) improved. Of the 22 patients with the sarcoid galaxy sign, 16(72.7%) improved. The patient with the reversed halo sign improved completely. Of the 52 patients with ground-glass opacities, 31(59.6%) improved. Of the 8 patients with air trapping, 7(87.5%) improved. Conclusions: The atypical imaging manifestations of thoracic sarcoidosis included unilateral hilar lymphadenopathy with or without mediastinal lymphadenopathy, mediastinal lymphadenopathy without hilar lymphadenopathy, patchy consolidation, the sarcoid galaxy sign, the reversed halo sign, ground-glass opacity, and air trapping. These lesions mostly improved after treatment. Familiarity with these atypical signs will help increase the diagnostic accuracy of imaging studies for thoracic sarcoidosis.

[MRI features of ventricular system tuberculosis]

OBJECTIVE

To study the MRI features of ventricular system tuberculosis.

METHODS

Nineteen patients with ventricular system tuberculosis in our hospital from Mar. 2009 to Sep. 2014 were retrospectively identified. Their clinical features and cranial MRI characteristics were reviewed.

RESULTS

There were 13 males and 6 females, aged from 15-81 years(mean 37±16). Eight patients had intraventricular tuberculosis, with 5 long striped or irregular shaped intraventricular tuberculosis and 3 with ventricular tuberculoma. Six patients had tubercular ependymitis and 5 had intraventricular tuberculosis along with tubercular ependymitis. The lesions of 14 patients were in the lateral ventricle; 13 in occipital or temporal horn of lateral ventricle, 9 complicated by tubercular meningitis, and 10 complicated by brain tuberculoma. The lesion of 5 patients were in the fourth ventricle, 5 in the postmedian of the fourth ventricle, 5 complicated by tubercular meningitis and 4 complicated by hydrocephalus. There were 4 cases with ring-enhancement and 15 with heterogeneous enhancement. Ten cases were complicated by peripheral edema.

CONCLUSIONS

The diagnosis of ventricle system tuberculosis is difficult due to its low incidence. The site, cranial MRI characteristics, the patterns of enhancement and complications have certain specificity and are useful in the diagnosis of ventricular system tuberculosis.

[Effect of double-J stent indwelling time in treatment of ureteric calculi complicated with infection]

OBJECTIVE

To evaluate the effect and double-J stent indwelling time in the treatment of acute upper urinary tract infection caused by ureteral calculi.

METHODS

A prospective non-randomized controlled study was carried out. From January 2011 to August 2015, a total of 142 patients treated in Department of Urology of Shanghai First People's Hospital for ureteral calculi with systematic inflammatory response syndrome were divided into double-J stent indwelling 7 days group (n=63) and double-J stent indwelling > 7 days group (n=79). The preoperative routine blood test, urinalysis, and urine culture, the urinalysis and urine culture immediately after double-J indwelling, and the routine blood test, urinalysis, and urine culture 7 days after indwelling were compared between the two groups. Postoperative complications after lithotripsy were analyzed.

RESULTS

There were no statistically significant differences in preoperative blood white blood cell (WBC) count, urine WBC count, and positive bacterial culture between the two groups (all P>0.05). Seven days after double-J stent indwelling, significant improvement was seen in both the 7 d group and the >7 d group in blood WBC count, urine WBC count, and positive urine culture [(8.1±1.7) vs (14.8±3.1) ×10(9)/L, (356±44) vs (3 077±643)/μl, 1.6% vs 52.4%; (7.9±1.1) vs (15.1±3.8) ×10(9)/L, (363±52) vs (3 122±805)/μl, 3.8% vs 48.1%], and infection was managed effectively, while no statistically significant inter-group differences were observed. There was no significant difference in stone clearance rate between the two groups (96.8% vs 96.2%, P>0.05). There was no significant difference in the incidence of postoperative complications, especially infectious complications (all P>0.05).

CONCLUSIONS

Indwelling double-J stents for 7 days could effectively manage the infection in patients with acute upper urinary tract infection secondary to ureteral calculi. These patients can be treated with lithotripsy safely. The time of double-J stent indwelling could be shortened.

Color tunable electroluminescence and resistance switching from a ZnO-nanorod-TaOx-p-GaN heterojunction

Well-aligned ZnO nanorods have been prepared on p-GaN-sapphire using a vapor phase transport (VPT) technique. A thin sputtered layer of TaOx is employed as the intermediate layer and an n-ZnO-TaOx-p-GaN heterojunction device has been achieved. The current transport of the heterojunction exhibited a typical resistance switching behavior, which originated from the filament forming and breaking in the TaOx layer. Color controllable electroluminescence (EL) was observed from the biased heterojunction at room temperature. Bluish-white wide band emission is achieved from the forward biased device in both the high resistance and low resistance states, while red emission can only be observed for the reverse biased device in the low resistance state. The correlation between the EL and resistance switching has been analyzed in-depth based on the interface band diagram of the heterojunction.

Expressional analysis of immune-related miRNAs in breast milk

Immune-related miRNAs in breast milk are extracellular miRNAs that are related to immune organ development and regulation of the immune function in infants and young animals. The goal of this study was to compare the expression levels of five immune-related miRNAs in breast milk in black goats, humans, and dairy cattle. The miRNAs from milk were extracted and the expression levels were assessed using quantitive RT-PCR methods. MiR-146, miR-155, miR-181a, miR-223, and miR-150 were all detected in Dazu black goat milk, and these miRNAs were significantly more highly expressed in colostrum than in mature milk of goats (P < 0.01), except for miR-150. Further, all five miRNAs were expressed in human colostrum, but patterns differed from those in goats: miR-146 and miR-155 were highly expressed (P < 0.01) in human colostrum, whereas miR-223 was abundant in goat colostrum (P < 0.01). In addition, five miRNAs were significantly higher in bovine mature milk than in goat milk (P < 0.01). Taken together, these results confirm that immune-related miRNAs are rich in breast milk with different expression levels depending on the lactation phase and species.

Genetic analysis of QTL for eye cross and eye diameter in common carp (Cyprinus carpio L.) using microsatellites and SNPs

A group of 107 F1 hybrid common carp was used to construct a linkage map using JoinMap 4.0. A total of 4877 microsatellite and single nucleotide polymorphism (SNP) markers isolated from a genomic library (978 microsatellite and 3899 SNP markers) were assigned to construct the genetic map, which comprised 50 linkage groups. The total length of the linkage map for the common carp was 4775.90 cM with an average distance between markers of 0.98 cM. Ten quantitative trait loci (QTL) were associated with eye diameter, corresponding to 10.5-57.2% of the total phenotypic variation. Twenty QTL were related to eye cross, contributing to 10.8-36.9% of the total phenotypic variation. Two QTL for eye diameter and four QTL for eye cross each accounted for more than 20% of the total phenotypic variation and were considered to be major QTL. One growth factor related to eye diameter was observed on LG10 of the common carp genome, and three growth factors related to eye cross were observed on LG10, LG35, and LG44 of the common carp genome. The significant positive relationship of eye cross and eye diameter with other commercial traits suggests that eye diameter and eye cross can be used to assist in indirect selection for many commercial traits, particularly body weight. Thus, the growth factor for eye cross may also contribute to the growth of body weight, implying that aggregate breeding could have multiple effects. These findings provide information for future genetic studies and breeding of common carp.

Equations of state, transport properties, and compositions of argon plasma: combination of self-consistent fluid variation theory and linear response theory

A consistent theoretical model that can be applied in a wide range of densities and temperatures is necessary for understanding the variation of a material's properties during compression and heating. Taking argon as an example, we show that the combination of self-consistent fluid variational theory and linear response theory is a promising route for studying warm dense matter. Following this route, the compositions, equations of state, and transport properties of argon plasma are calculated in a wide range of densities (0.001-20 g/cm(3)) and temperatures (5-100 kK). The obtained equations of state and electrical conductivities are found in good agreement with available experimental data. The plasma phase transition of argon is observed at temperatures below 30 kK and density about 2-6g/cm(3). The minimum density for the metallization of argon is found to be about 5.8 g/cm(3), occurring at 30-40 kK. The effects of many-particle correlations and dynamic screening on the electrical conductivity are also discussed through the effective potentials.

Polarization-independent electrically tunable/switchable Airy beam based on polymer-stabilized blue phase liquid crystal

Because of their non-diffraction and freely acceleration during propagation, finite energy Airy beams are interesting for application such as optical manipulation, plasma channel generation and optical vortex generation. Especially interesting are tunable/switchable Airy beams, in which the Airy beam tuning by electric field, temperature or optical intensity can be realized. Here we experimentally demonstrate polarization-independent, electrically tunable/switchable Airy beam based on polymer-stabilized blue phase liquid crystals with wide working temperature range and fast response time through a structure called vertical field driven mode.

Histidine supplementation improves insulin resistance through suppressed inflammation in obese women with the metabolic syndrome: a randomised controlled trial

AIMS/HYPOTHESIS

Increased inflammation and oxidative stress are associated with insulin resistance (IR) and metabolic disorders. Serum histidine levels are lower and are negatively associated with inflammation and oxidative stress in obese women. The objective of this study was to evaluate the efficacy of histidine supplementation on IR, inflammation, oxidative stress and metabolic disorders in obese women with the metabolic syndrome (MetS).

METHODS

A total of 100 obese women aged 33-51 years with BMI ≥ 28 kg/m² and diagnosed with MetS were included following a health examination in the community hospital in this randomised, double-blinded, placebo-controlled trial. Participants were allocated to interventions by an investigator using sequentially numbered sealed envelopes and received 4 g/day histidine (n = 50) or identical placebo (n = 50) for 12 weeks. Participants then attended the same clinic every 2 weeks for scheduled interviews and to count tablets returned. Serum histidine, HOMA-IR, BMI, waist circumference, fat mass, serum NEFA, and variables connected to inflammation and oxidative stress were measured at baseline and 12 weeks. Participants, examining physicians and investigators assessing the outcomes were blinded to group assignment. In addition, the inflammatory mechanisms of histidine were also explored in adipocytes.

RESULTS

At 12 weeks, a total of 92 participants completed this trail. Compared with the placebo group (n = 47), histidine supplementation significantly decreased HOMA-IR (-1.09 [95% CI -1.49, -0.68]), BMI (-0.86 kg/m² [95% CI -1.55, -0.17]), waist circumference (-2.86 cm [95% CI -3.86, -1.86]), fat mass (-2.71 kg [95% CI -3.69, -1.73]), serum NEFA (-173.26 μmol/l [95% CI -208.57, -137.94]), serum inflammatory cytokines (TNF-α, -3.96 pg/ml [95% CI -5.29, -2.62]; IL-6, -2.15 pg/ml [95% CI -2.52, -1.78]), oxidative stress (superoxide dismutase, 17.84 U/ml [95% CI 15.03, 20.65]; glutathione peroxidase, 13.71 nmol/ml [95% CI 9.65, 17.78]) and increased serum histidine and adiponectin by 18.23 μmol/l [95% CI 11.74, 24.71] and 2.02 ng/ml [95% CI 0.60, 3.44] in histidine supplementation group (n = 45), respectively. There were significant correlations between changes in serum histidine and changes of IR and its risk factors. No side effects were observed during the intervention. In vitro study indicated that histidine suppresses IL6 and TNF mRNA expression and nuclear factor kappa-B (NF-κB) protein production in palmitic acid-induced adipocytes in a dose-dependent manner, and these changes were diminished by an inhibitor of NF-κB.

CONCLUSIONS/INTERPRETATION

Histidine supplementation could improve IR, reduce BMI, fat mass and NEFA and suppress inflammation and oxidative stress in obese women with MetS; histidine could improve IR through suppressed pro-inflammatory cytokine expression, possibly by the NF-κB pathway, in adipocytes.

Split ring aperture for optical magnetic field enhancement by radially polarized beam

Inspired by Babinet's principle, we proposed a new plasmonic structure for enhancing the optical magnetic field, i.e. split ring aperture, whose complement is the well-known split ring. The split ring aperture exhibits a much better performance under radially polarized excitation than linearly polarized excitation. We attribute the ultra-high intensity enhancement in magnetic field to the symmetric matching between the aperture geometry and the direction of the electric field vector in each direction of radially excitation. The impact of the design parameters on the intensity enhancement and resonant wavelength is also investigated in details.

Spatial angle dependent lasing from a dye-doped two-dimensional hexagonal photonic crystal made of holographic polymer-dispersed liquid crystals

The observation of spatial angle dependent lasing from a dye-doped two-dimensional photonic crystal (2D PC) holographic polymer dispersed liquid crystals made of hexagonal lattice structure is reported. With the increasing output angle of the laser beam in the plane perpendicular to the 2D PC, the lasing wavelength is red-shifted. By analyzing the lasing oscillation trace, we found that the effective lattice constant changes with the output angle, causing the spatial angle dependent lasing.

Free-standing ZnO-CuO composite nanowire array films and their gas sensing properties

A modified hydrothermal method was developed to synthesize ZnO-CuO composite nanostructures. A free-standing film made of ZnO-CuO nanostructures was assembled on the surface of the hydrothermal solution with a smooth surface on one side and a spherical surface on the other side. The structure, growth mechanism and the optical properties of the composite nanostructures were studied. Structural characterizations indicate that the composite nanostructure mainly consisted of two single-crystal phases of CuO and ZnO. The sensitivity for CO gas detection was significantly improved for the composite CuO-ZnO nanostructure film. This method offers a possible route for the fabrication of free-standing nanostructure films of different functional composite oxides.

Propagation properties of an optical vortex carried by an Airy beam: experimental implementation

In this Letter, we experimentally studied the propagation dynamics of Airy beams (AiBs) carrying phase singularity or an optical vortex (OV). A 3/2 phase mask encoded with phase singularity was used to generate AiBs and OVs enjoying precise position alignment and compact optical configuration simultaneously. Experimental results showed that the OV deflection velocity was faster than that of the main lobe of the AiB, agreeing with the analytical prediction. Numerical simulation results are also in agreement with the experimental results. Furthermore, OVs with larger topological charges were also studied experimentally with the same approach.

Improved performance of organic light-emitting diodes with MoO3 interlayer by oblique angle deposition

We fabricated and demonstrated improved organic light emitting diodes (OLEDs) in a thin film architecture of indium tin oxide (ITO)/ molybdenum trioxide (MoO3) (20 nm)/N,N'-Di(naphth-2-yl)-N,N'-diphenyl-benzidine (NPB) (50 nm)/ tris-(8-hydroxyquinoline) (Alq3) (70 nm)/Mg:Ag (200 nm) using an oblique angle deposition technique by which MoO3 was deposited at oblique angles (θ) with respect to the surface normal. It was found that, without sacrificing the power efficiency of the device, the device current efficiency and external quantum efficiency were significantly enhanced at an oblique deposition angle of θ=60° for MoO3.

Propagation dynamics of an optical vortex imposed on an Airy beam

In this Letter, we demonstrate the general propagation dynamics of an Airy beam (AiB) carrying unit phase singularity, i.e., optical vortices (OVs). For the OV with a unit charge, theoretical analysis indicates that the OV carried by the AiB will propagate along the parabolic trajectory with an acceleration velocity twice as fast as conventional AiBs before a critical position. Thereafter, the AiB main lobe destroyed by OV will be reconstructed and the phase singularity will reappear in the middle of the AiB profile.

One-dimensional single-crystalline bismuth oxide micro/nanoribbons: morphology-controlled synthesis and luminescent properties

Based on a facile vapor-phase transport method without any catalyst and template, one-dimensional single-crystalline bismuth oxide (Bi2O3) micro/nanoribbons were fabricated on silicon substrates in large quantities and morphology-controlled fabrication of Bi2O3 was achieved from a single precursor. The widths of Bi2O3 ribbons varied from 0.2 to 20 microm depending on the deposition temperatures. The thickness was in the range of 0.1-2 microm and the length reached several hundred micrometers and even millimeter range. The detailed composition and structural analysis confirmed the single-crystalline nature of alpha-Bi2O3 micro/nanoribbons with monoclinic structure. The photoluminescence spectrum of a single Bi2O3 ribbon showed a broadband emission from 450 to 750 nm in the visible region, consisting two peaks located at 589 and 697 nm which were primarily originated from the impurity ions and crystal defects. A self-catalyzed vapor-solid model was proposed to account for the growth mechanism of Bi2O3 ribbons with different morphologies.

A set of polymorphic trinucleotide and tetranucleotide microsatellite markers for silver crucian carp (Carassius auratus gibelio) and cross-amplification in crucian carp

Silver crucian carp (Carassius auratus gibelio Bloch), as a gynogenetic fish, is a promising model for the study of the evolutionary genetics of vertebrates. We have developed 59 polymorphic trinucleotide and tetranucleotide markers for the silver crucian carp through the biotin capture method and radioactive-labeling hybridization. The number of alleles ranged from 2 to 12 in the population, and the average proportion of heterozygotes (including tri- and diallelic) at polymorphic loci was 76.8%. In addition, these loci were successfully applied to a close relative, the crucian carp (Carassius auratus), by cross-amplification, as shown by the range of alleles (2-19), observed heterozygosity (0.1765-0.9706), expected heterozygosity (0.2392-0.9421), and polymorphism information content (0.2186-0.9236).

N-P transition sensing behaviors of ZnO nanotubes exposed to NO2 gas

Hydrothermally synthesized ZnO nanotube arrays were used to fabricate the gas sensor for detection of the toxic gas NO2. The ZnO nanotube gas sensor exhibited sensitive response to NO2 down to 500 ppb at low temperature 30 degrees C. Abnormal temperature-dependent and concentration-dependent N-P transition behaviors were observed. The excellent sensing ability of the sensor and their anomalous conductivity behaviors may be attributed to the unique surface conductivity related to the hollow nanostructure feature. These sensing behaviors may help to comprehensively understand the sensing mechanism of 1D ZnO nanostructures and improve the selectivity of the ZnO gas sensor.

Airy beams generated by a binary phase element made of polymer-dispersed liquid crystals

Using polymer-dispersed liquid crystals (PDLCs), an electrically switchable binary phase pattern was fabricated to generate Airy beams through a programmable lithographic system. The right main lobe of the reconstructed Airy beam experienced 1.3 mm transverse deflection within 24 cm propagation distance. With a suitable voltage applied, the binary PDLC pattern can be erased due to the index match between polymers and liquid crystals. This versatile approach can be also used to generate other special beams with electrically tunable capability.

Electrically switchable computer-generated hologram using a liquid crystal cell with a proton beam patterned polymethylmethacrylate substrate

An electrically switchable computer-generated hologram (CGH) was fabricated using a liquid crystal (LC) cell. A polymethylmethacrylate (PMMA) film, which was spin-coated on one glass substrate of the LC cell, was patterned by a focused 2 MeV proton beam with a CGH phase pattern (2 microm resolution). With an applied voltage on the LC cell CGH sample, an index modulation was produced between the regions with and without PMMA because of the reorientation of LC molecules under the external electric field. The maximum diffraction efficiency measured was about 28.7%. The operating voltage was below 15 V(rms).

White beam diffraction in a two-dimensional photonic crystal

We investigate diffraction of a white beam in a two-dimensional photonic crystal. Experimental and computational results for a halogen light source are presented. Applying equal-frequency surface analysis, we reproduce the experimental results by computer simulations. The white beam is modeled computationally as a sum of many circular rings; each ring is made up of many wavelength components. We also present computer simulations of the diffraction pattern for a fluorescent light source.

Ferroelectric transistors with nanowire channel: toward nonvolatile memory applications

We report the fabrication and characterization of ZnO nanowire memory devices using a ferroelectric Pb(Zr(0.3)Ti(0.7))O(3) (PZT) film as the gate dielectric and the charge storage medium. With a comparison to nanowire transistors based on SiO(2) gate oxide, the devices were evaluated in terms of their electric transport, retention, and endurance performance. Memory effects are observed as characterized by an eminent counterclockwise loop in I-V(g) curves, which is attributed to the switchable remnant polarization of PZT. The single-nanowire device exhibits a high (up to 10(3)) on/off ratio at zero gate voltage. Our results give a proof-of-principle demonstration of the memory application based on a combination of nanowires (as channels) and ferroelectric films (as gate oxide).

A negative-positive tunable liquid-crystal microlens array by printing

A tunable microlens array by printing was demonstrated. An UV-curable adhesive, NOA65, was printed and cured to form a lens array profile on an ITO glass. Then this microlens array ITO glass was assembled with a normal ITO glass to form a cell, which was later filled with a liquid crystal. The focal length of the lens array can be tuned by an electric field, which changes the index difference between liquid crystals and NOA65 due to the reorientation of the LC molecules. In our experiment, the focal length varied from -2.29 cm to 3.12 cm when the applied voltage was increased from 0 V to 13.26 V.

Low propagation loss SiN optical waveguide prepared by optimal low-hydrogen module

We investigated low-hydrogen SiN films prepared by a low temperature (350 degrees C) PECVD method. The impact of SiH(4)/N(2) flow ratio and radio frequency power on the hydrogen content in the SiN films was studied. In this work, we demonstrated a low-loss sub-micron SiN waveguide by using the corresponding optimal SiN films. The propagation loss was found to be as low as -2.1+/-0.2 dB/cm at 1550 nm with waveguide cross-section of 700 nm x 400 nm. The results suggest that the SiN films grown by PECVD with low hydrogen can be used in photonics integrated circuits for new generation communications applications.

Fast switching electrochromic display using a viologen-modified ZnO nanowire array electrode

We report an electrochromic (EC) display using a viologen-modified ZnO nanowire array as the EC electrode. The ZnO nanowire array was grown directly on an indium tin oxide (ITO) glass by a low temperature aqueous thermal decomposition method and then modified with viologen molecules. The ZnO nanowire electrochromic device shows fast switching time (170 and 142 ms for coloration and bleaching respectively for a 1 cm (2) cell), high coloration efficiency (196 C (-1) cm (2)) and good stability. The improved performance of the ZnO nanowires EC device can be attributed to the large surface area and high crystalline and good electron transport properties of the ZnO nanowire array.

Out-of-plane diffraction of a two-dimensional photonic crystal with finite dielectric modulation

We present a generalized picture of out-of-plane diffraction in a two-dimensional photonic crystal using the concept of photonic bands and employing a three-dimensional, equal-frequency-surface analysis. We show that the discrete spots of diffraction pattern in a weakly modulated photonic crystal, including those of conventional diffraction gratings, become continuous when the dielectric modulation becomes finite. Furthermore, in a finite-modulated photonic crystal, the diffraction can take place even in the region prohibited by Bragg's law: there are available states for the incident light, which are evanescent in the case of a diffraction grating (weakly modulated photonic crystal).

A ZnO nanorod inorganic/organic heterostructure light-emitting diode emitting at 342 nm

An inorganic/organic heterostructure light-emitting diode consisting of the hole-transporting layer N, N'-di(naphth-2-yl)- N, N'-diphenylbenzidine (NPB) and n-type ZnO nanorods fabricated by hydrothermal decomposition is reported. Poly(methyl methacrylate) was used to form a smooth surface on top of ZnO nanorod array with ZnO nanorod tops exposed for subsequent NPB deposition. An unusual ultraviolet emission at 342 nm was observed in the electroluminescence spectrum. Compared to band gap energy of ZnO (3.37 eV), the excitonic emission is blue-shifted and broadened. The mechanism of the blue shift is discussed in terms of the energy band diagram of the heterostructure.

Equal-frequency surface analysis of two-dimensional photonic crystals

This paper presents an analytical treatment of equal-frequency surface analysis of a two-dimensional photonic crystal. We first define the equal-frequency surface in terms of plane waves, which can be numerically evaluated. Then one- and two-plane-wave approximations are proposed, which consequently lead to analytical expressions of the equal-frequency surface. The approach presented is well suited to two-dimensional photonic crystals of weak dielectric modulation. For photonic crystals with a large modulation, the approach can be used to gain a general idea of the shape of the bands.

Electrically switchable optical vortex generated by a computer-generated hologram recorded in polymer-dispersed liquid crystals

A computer-generated hologram designed to generate an optical vortex was recorded in a cell filled with polymer-dispersed liquid crystal material under a collimated Ar+ laser beam operating at 514.5 nm. Owing to the photopolymerization-induced phase separation between the polymer and the liquid crystal, an index modulation was formed between the polymer-rich and liquid crystal-rich regions. A good optical vortex beam with high fidelity was reconstructed using a collimated He-Ne laser beam. The diffraction efficiency is estimated to be about 13%-17%. With a suitable voltage applied, the reconstructed optical vortex beam can be switched owing to the index change between the polymer and the liquid crystal.

Observation of excitonic quenching by long-range dipole-dipole interaction in sequentially doped organic phosphorescent host-guest system

We studied the quenching mechanisms responsible for the low efficiency of thin film phosphorescence by a specially designed organic light-emitting diode with an emission layer consisting of a few repeating cells made of a sequentially evaporated host and guest. Variation of the thickness of the guest layer in each cell enables the study of the effect of molecule aggregation on the quantum efficiency. On the other hand, variation of the thickness of the host layer reveals a new long-range quenching mechanism involving a Förster-like dipole-dipole interaction. The quantitative analysis shows that the external quantum efficiency as a function of the host layer thickness follows the characteristic of the long-range Förster process. Our study provides a new understanding of quenching mechanisms in phosphorescent material and extends the existing knowledge on long-range energy transfer.

First-principles study of the elastic and thermodynamic properties of CaSiO(3) perovskite

The thermodynamic and elastic properties of CaSiO(3) perovskite are investigated at high pressures and temperatures using the plane wave pseudopotential method within the local density approximation. The athermal elastic moduli of CaSiO(3) perovskite are calculated as a function of pressure up to 200 GPa. The calculated results are in excellent agreement with available experimental data at high pressure, and compare favourably with other pseudopotential predictions over the pressure regime studied. It is also found that the elastic anisotropy drops rapidly with the increase of pressure initially, and then decreases more slowly at higher pressures. The thermodynamic properties of CaSiO(3) perovskite are predicted using the quasi-harmonic Debye model for the first time; the heat capacity and the thermal expansion coefficient agree with the observed values at ambient conditions and the other calculations at high pressures and temperatures.

Enhanced field emission from injector-like ZnO nanostructures with minimized screening effect

Injector-like zinc oxide (ZnO) nanostructures have been synthesized on Si substrate by the vapour phase transport method. Samples with different areal densities were obtained by controlling the temperature. The field emission properties of the injector-like ZnO nanostructures showed a clear dependence on the areal density of the nanostructures, which is due to the screening effect. The samples with a needle length of 850 nm and an areal density of 1 × 10(8) cm(-2) showed the lowest field emission turn-on field of 1.85 V µm(-1) at a current density of 10 µA cm(-2), and the current density reaches 1 mA cm(-2) at an applied field of 4.7 V µm(-1).

Tunable Fano resonance in photonic crystal slabs

A three dimensional analysis of a special class of anisotropic materials is presented. We introduce an extension of the Scattering Matrix Method (SMM) to investigate the behavior of anisotropic Photonic Crystal Slabs (PhCS) subject to external radiation. We show how the Fano effect can play a fundamental role in the realization of tunable optical devices. Moreover, we show how to utilize electron injection, electric field and temperature as parameters to control the Fano resonance shift in both isotropic and anisotropic materials as Si and Potassium Titanium Oxide Phosphate (KTP). We will see that because Fano modes are sensitive and controllable, a broad range of applications can be considered.

Symmetry properties of two-dimensional anisotropic photonic crystals

A theoretical study of two-dimensional photonic crystals made of anisotropic material is presented. Detailed computation principles including a treatment of the TE and TM polarizations are given for a photonic crystal made of either uniaxially or biaxially anisotropic materials. These two polarizations can be decoupled as long as any one of the principal axes of the anisotropic material is perpendicular to the periodic plane of the photonic crystal. The symmetry loss due to the anisotropy of the material and the variation of the Brillouin zones relative to the tensor orientations are also analyzed. Furthermore, the symmetry properties of the two-dimensional photonic band structure are studied, and the resulting effect on the photonic bandgap and the dispersion properties of photonic crystal are analyzed as a function of the orientation of the anisotropic material.

Tunable fly's-eye lens made of patterned polymer-dispersed liquid crystal

A fly's-eye lens was fabricated using polymer-dispersed liquid crystals and its optical properties were evaluated. The morphologies were examined under an optical microscope. The forming process has been simulated based on a patterned photo-polymerization technique in which the spatially modulated reaction rate has been coupled with the time-dependent Ginzburg-Landau (TDGL) equations with the free energies relating to isotropic mixing, nematic ordering, and network elasticity incorporated. The simulated results are in good agreement with the experimental results. The beam profile was tested using a CCD. The results showed that this fly's-eye lens could modulate a Gaussian beam into a mesa-like beam. Such device is potentially useful in beam shaping and many illumination systems that require uniform beam profile.

Tunable superprism and polarization splitting in a liquid crystal infiltrated two-dimensional photonic crystal made of silicon oxynitride

Tunable superprism and polarization splitting effects, based on liquid-crystal infiltrated two-dimensional photonic crystal with SiON as a background material, are demonstrated. Owing to the strong birefringence of the liquid crystal, the dispersion curves of the two polarizations are distinctly different, resulting in large splitting between the two polarizations. Extremely large splitting, as large as 80 degrees, can be obtained. Moreover, the splitting can be tuned to a substantial degree when the optic axis of the liquid crystal is reoriented. Fully controllable, incident-angle-dependent and wavelength-dependent superprism effects are also demonstrated. This large swing in the refraction can be completely switched off by reorientation of the optic axis of the liquid crystal, thus to resemble bulk media refraction.

Growth mechanism of tubular ZnO formed in aqueous solution

Tubular ZnO microstructural arrays were fabricated by a hydrothermal decomposition method. The dependence of the morphologies on the growth time and temperature was investigated in detail. An experiment was carried out to determine the mechanism of tubular ZnO formation. Our results showed that ZnO microtubes originated from an ageing process from ZnO microrods at a lower temperature (compared to the temperature when hydrothermal deposition of ZnO microrods was dominant) due to the preferential chemical dissolution of the metastable Zn-rich (0001) polar surfaces. A growth model was proposed based on the coexistence of hydrothermal deposition and dissolution of ZnO in the fabrication process.