A Route to Conjugated Monomers and Polymers Incorporating 2,5-Connected Oxazole in the Backbone.

Joining of imidazole, pyrimidine, and oxazole to other conjugated core units was explored in pursuit of yielding monomers to synthesize organic semiconducting polymers. Regioregular oxazole-flanked thiophene, benzothiadiazole, naphthalene diimide (NDI), and thienopyrroledione (TPD) were successfully isolated via stannylation of oxazole and the Stille coupling of brominated core units (overall yields ranging from ca. 40 to 60%). From subsequent direct arylation polymerization, NDI/oxazole/TPD-containing regioisomeric polymers were obtained with optical and electrochemical orbital energetics in the semiconducting regime.

Benzothiadiazole versus Thiazolobenzotriazole: A Structural Study of Electron Acceptors in Solution-Processable Organic Semiconductors.

Despite the rapid progress of organic electronics, developing high-performance n-type organic semiconductors is still challenging. Donor-acceptor (D-A) type conjugated structures have been an effective molecular design strategy to achieve chemically-stable semiconductors and the appropriate choice of the acceptor units determines the electronic properties and device performances. We have now synthesized two types of A1 -D-A2 -D-A1 type conjugated molecules, namely, NDI-BTT-NDI and NDI-TBZT-NDI, with different central acceptor units. In order to investigate the effects of the central acceptor units on the charge-transporting properties, organic field-effect transistors (OFETs) were fabricated. NDI-TBZT-NDI had shallower HOMO and deeper LUMO levels than NDI-BTT-NDI. Hence, the facilitated charge injection resulted in ambipolar transistor performances with the optimized hole and electron mobilities of 0.00134 and 0.151 cm2 V-1 s-1 , respectively. In contrast, NDI-BTT-NDI displayed only an n-channel OFET performance with the electron mobility of 0.0288 cm2 V-1 s-1 . In addition, the device based on NDI-TBZT-NDI showed a superior air stability to that based on NDI-BTT-NDI. The difference in these OFET performances was reasonably explained by the contact resistance and film morphology. Overall, this study demonstrated that the TBZ acceptor is a promising building block to create n-type organic semiconductors.

Tuning Ambipolarity of the Conjugated Polymer Channel Layers of Floating-Gate Free Transistors: From Volatile Memories to Artificial Synapses.

Three-terminal synaptic transistor has drawn significant research interests for neuromorphic computation due to its advantage of facile device integrability. Lately, bulk-heterojunction-based synaptic transistors with bipolar modulation are proposed to exempt the use of an additional floating gate. However, the actual correlation between the channel's ambipolarity, memory characteristic, and synaptic behavior for a floating-gate free transistor has not been investigated yet. Herein, by studying five diketopyrrolopyrrole-benzotriazole dual-acceptor random conjugated polymers, a clear correlation among the hole/electron ratio, the memory retention characteristic, and the synaptic behavior for the polymer channel layer in a floating-gate free transistor is described. It reveals that the polymers with balanced ambipolarity possess better charge trapping capabilities and larger memory windows; however, the high ambipolarity results in higher volatility of the memory characteristics, namely poor memory retention capability. In contrast, the polymer with a reduced ambipolarity possesses an enhanced memory retention capability despite showing a reduced memory window. It is further manifested that this enhanced charge retention capability enables the device to present artificial synaptic characteristics. The results highlight the importance of the channel's ambipolarity of floating-gate free transistors on the resultant volatile memory characteristics and synaptic behaviors.

Association between gene polymorphism of GRK5 and breast cancer risk in Chinese population.

PURPOSE: Potential influences of GRK5 polymorphism on cancer risks have been reported. This study aimed to explore the distribution of GRK5 genotypes and alleles in Chinese breast cancer (BCa) patients, and to analyze the association between GRK5 and BCa risk. METHODS: Blood samples were collected from 412 BCa patients and 533 healthy individuals for isolating genomic DNA. GRK5 polymorphisms of Gln41Leu A > T and Arg304His G > A, and their alleles were detected using PCR-RFLP. Their influences on BCa susceptibility and pathological indexes were analyzed using Logistic regression model. RESULTS: No significant differences in age, body mass index (BMI) and smoking status were found between BCa patients and healthy persons, while significant differences were detected in drinking status, family history of cancer, hypertension and diabetes. GRK5Gln41Leu A > T and its allele frequency distribution were correlated to BCa susceptibility, while GRK5 Arg304His G > A was not. Higher risks of GRK5 Gln41Leu A > T and Arg304His G > A indicated a higher susceptibility to BCa. Compared with people carrying 0-1 risk allele, those carrying 2-4 risk alleles of GRK5 Gln41Leu A > T and Arg304His G > A of had a higher susceptibility to BCa, manifesting as worse tumor staging and grading, and higher rates of estrogen receptor (ER) (-), progesterone receptor (PR) (-) and HER2 (-). CONCLUSIONS: Gln41Leu A > T and Arg304His G > A fusion gene polymorphisms of GRK5 are vital genetic susceptibility genes to BCa. Our findings require to be validated in a multicenter study with a high-quality large sample size.

Combination of procalcitonin and C-reactive protein levels in the early diagnosis of bacterial co-infections in children with H1N1 influenza.

OBJECTIVE: This study evaluated the diagnostic value of measuring the levels of procalcitonin (PCT) and C-reactive protein (CRP) to differentiate children co-infected with H1N1 influenza and bacteria from children infected with H1N1 influenza alone. METHODS: Consecutive patients (children aged < 5 years) with laboratory-confirmed H1N1 influenza who were hospitalized or received outpatient care from a tertiary-care hospital in Canton, China, between January 1, 2012, and September 1, 2017, were included in the present study. Laboratory results, including serum PCT and CRP levels, white blood cell (WBC) counts, and bacterial cultures, were analyzed. The predictive value of the combination of biomarkers versus any of the biomarkers alone for diagnosing bacterial co-infections was evaluated using logistic regression analyses. RESULTS: Significantly higher PCT (1.46 vs 0.21 ng/mL, P < 0.001) and CRP (19.20 vs 5.10 mg/dL, P < 0.001) levels were detected in the bacterial co-infection group than in the H1N1 infection-alone group. Using PCT or CRP levels alone, the areas under the curves (AUCs) for predicting bacterial co-infections were 0.801 (95% CI, 0.772-0.855) and 0.762 (95% CI, 0.722-0.803), respectively. Using a combination of PCT and CRP, the logistic regression-based model, Logit(P) = -1.912 + 0.546 PCT + 0.087 CRP, showed significantly greater accuracy (AUC: 0.893, 95% CI: 0.842-0.934) than did the other three biomarkers. CONCLUSIONS: The combination of PCT and CRP levels could provide a useful method of distinguishing bacterial co-infections from an H1N1 influenza infection alone in children during the early disease phase. After further validation, the flexible model derived here could assist clinicians in decision-making processes.

Effects of Ambient Gases on the Electrical Performance of Solution-Processed C8-BTBT Thin-Film Transistors.

We performed a systematic study of the influence of environmental conditions on the electrical performance characteristics of solution-processed 2,7-dioctyl [1] benzothieno[3,2-b][1]-benzothiophene (C8-BTBT) thin-film transistors (TFTs). Four environmental exposure conditions were considered: high vacuum (HV), O2, N2, and air. The devices exposed to O2 and N2 for 2 h performed in a manner similar to that of the device kept in HV. However, the device exposed to air for 2 h exhibited significantly better electrical properties than its counterparts. The average and highest carrier mobility of the 70 air-exposed C8-BTBT TFTs were 4.82 and 8.07 cm2V-1s-1, respectively. This can be compared to 2.76 cm2V-1s-1 and 4.70 cm2V-1s-1, respectively, for the 70 devices kept in HV. Furthermore, device air stability was investigated. The electrical performance of C8-BTBT TFTs degrades after long periods of air exposure. Our work improves knowledge of charge transport behavior and mechanisms in C8-BTBT OTFTs. It also provides ideas that may help to improve device electrical performance further.

Evaluation and accurate diagnoses of pediatric diseases using artificial intelligence.

Artificial intelligence (AI)-based methods have emerged as powerful tools to transform medical care. Although machine learning classifiers (MLCs) have already demonstrated strong performance in image-based diagnoses, analysis of diverse and massive electronic health record (EHR) data remains challenging. Here, we show that MLCs can query EHRs in a manner similar to the hypothetico-deductive reasoning used by physicians and unearth associations that previous statistical methods have not found. Our model applies an automated natural language processing system using deep learning techniques to extract clinically relevant information from EHRs. In total, 101.6 million data points from 1,362,559 pediatric patient visits presenting to a major referral center were analyzed to train and validate the framework. Our model demonstrates high diagnostic accuracy across multiple organ systems and is comparable to experienced pediatricians in diagnosing common childhood diseases. Our study provides a proof of concept for implementing an AI-based system as a means to aid physicians in tackling large amounts of data, augmenting diagnostic evaluations, and to provide clinical decision support in cases of diagnostic uncertainty or complexity. Although this impact may be most evident in areas where healthcare providers are in relative shortage, the benefits of such an AI system are likely to be universal.

[A 10-day sequential therapy for eradication of Helicobacter pylori infection in children].

OBJECTIVE: To evaluate the clinical effect of a 10-day sequential therapy which was made up of omeprazole, clarithromycin, amoxicillin-clavulanate and metronidazole for the eradication of Helicobacter pylori (Hp) infection in children. METHOD: A total of 214 children with abdominal pain, who were confirmed to have Hp infection through endoscopy, biopsy, and Hp culture. The 214 cases were randomly divided into four groups. A 10-day sequential therapy group accepted omeprazole 0.8 - 1.0 mg/(kg·d) plus amoxicillin-clavulanate 50 mg/(kg·d) for five days and omeprazole 0.8 - 1.0 mg/(kg·d), clarithromycin 20 mg/(kg·d) and metronidazole 20 mg/(kg·d) for the remaining five days. The 7-day triple therapy group, 10-day triple therapy group and 14-day triple therapy group received omeprazole 0.8 - 1.0 mg/(kg·d), amoxicillin-clavulanate 50 mg/(kg·d) and clarithromycin 20 mg/(kg·d) for 7 days,10 days,14 days, respectively. All drugs were given twice daily. All these patients received (13)C urea breath test ((13)C-UBT) four weeks after the treatment. RESULT: Finally, 199 patients were followed up, and the total rate of loss to follow-up was 7.0% (15/214). Hp eradication rate was 85.2% and 90.2% in the 10-day sequential therapy group on intention to treat (ITT) and per protocol (PP) analyses, 66.0% and 71.4% in the 7-day triple therapy group on ITT and PP analyses; 60.0% and 67.3% in 10-day triple therapy group on ITT and PP analyses, and 78.8% and 82.0% in patients who received the 10-day sequential regimen on ITT and PP analyses, respectively. By ITT analysis, there was significantly difference between the 10-day sequential therapy group and 7-day or 10-day triple therapy group (P < 0.05), while no significant difference was found between the 10-day sequential therapy group and 14-day triple therapy group (P > 0.05). The results of the ITT analysis and the PP analysis were the same. The four groups had neither significant difference in abdominal pain relief (P > 0.05) nor in incidence of adverse reactions (P > 0.05). CONCLUSION: The 10-day sequential regimen was significantly more effective than both 7-day triple regimen and 10-day triple regimen, while had the same eradication rate compared with the 14-day sequential therapy. But 10-day triple regimen to eradicate Hp infection in children had the advantages such as short course of treatment and better compliance.

[Balloon dilation with gastroscope for esophageal stricture in children].

OBJECTIVE: To evaluate the efficacy and safety of balloon dilation (BD) with gastroscope in treatment of esophageal stricture in children. METHODS: BD was performed in 12 children aged 5 - 59 months, average age 26 months, course of disease was 2 - 26 months, with esophageal stricture, 7 cases with anastomotic strictures secondary to surgical repair of esophageal atresia, 3 with congenital esophageal stenosis, 2 with corrosive esophageal strictures. All procedures were performed under tracheal intubation and intravenous anesthesia using the 3rd grade controlled radial expansion (CRE) esophagus-balloon with gastroscope. Firstly the balloon was inserted into the esophagus through mouth, then put in the gastroscope. Under the direct guidance of gastroscope the balloon was positioned across the stricture, then the balloon was filled with saline to get needed pressure and maintained for 3 minutes. The procedure was repeated 3 times at an interval of 3 minutes. The abdominal pain, melena and vomiting were observed, as well as the diet taken thereafter, the size of the stricture and the nutrition status were observed for 3 to 12 months after the dilation. RESULTS: Twenty-two dilations were performed in 12 cases, 19 succeeded, 3 cases developed complication during the dilation, the total success rate was 86%. The procedure failed in 3 cases and succeeded in 9 cases, the effective rate was 75%. Follow-up and repeated gastroscopy were performed within 3 to 12 months after the dilation, the diameter of the stricture was 9-13 mm, compared with 2-8 mm before the dilation. Eight of the children could take solid food and nutritional status was improved. CONCLUSIONS: BD with the 3rd grade CRE esophagus-balloon under gastroscopy is a simple and effective method to treat esophagus stricture in children, especially for anastomotic strictures secondary to surgical repair of esophageal atresia.

[Genotypic study on the Helicobacter pylori vacA, cagA and iceA genes in the infected children in Guangzhou area].

OBJECTIVE: To investigative vacA, cagA and iceA genes dominant genotypes of Helicobacter pylori (Hp) isolated from children suffering from gastric and duodenal diseases in Guangzhou area. METHODS: Totally 105 children who underwent gastroscopy in Guangzhou Children's Hospital were enrolled into this study. From each patient, 3 biopsy specimens from the gastric antrum were taken, one was used for rapid urease test, one for histological examination, and one for polymerase chain reaction (PCR) for detecting ureA, vacA, cagA, and iceA genes. DNA was prepared directly from the biopsy specimens from the gastric antrum using a QIAamp DNA mini kit (Qiagen, Germany) according to the manufacturer's instructions. Then 11 primers were used for detecting the genotypes including ureas, (s1, s1a, s1b, s1c, s2) and m (m1, m1T, m2) region of vacA, cagA and iceA (iceA1 and iceA2) genotypes in the 105 children. The distribution of the genotypes of Hp was analyzed. RESULT: Among the 105 children, only 52 children were positive by the three methods, among these 52 children, 26 were boys and 26 girls. Hp vacA s1as1c/m2 was detected in 43 out of 52 children (82.7%), s1as1c/m1T in 9.6% (5/52), m region that could not betyped was 7.7% (4/52). No strains presented genotypes vacA s1b, s2, m1. The comparison of the positive ratio of vacA s1as1 c/m2 detected in the children infected with Hp and that of the other combination of signal region and middle region was statistically significantly different (P < 0.01). With regard to cagA gene, cagA(+) gene and cagA(-) gene were found in 90.4% (47/52) and 9.6% (5/52) of the children, respectively. The cagA(+) gene was more frequent in the children infected with Hp. Single iceA1 was detected in 78.8% (41/52) children, and single iceA2 was detected to be 1.9% (1/52), multiple strains infection of iceA1 and iceA2 were detected in 3.8% (2/52) children, iceA1 and iceA2 were not detected in 15.4% (8/52), the comparison of the positive ratio of iceA1 detected in the children infected with Hp and that of the other genotypes was statistically significantly different (P < 0.01). CONCLUSION: The s1as1c/m2, cagA and iceA1 were the dominant genotypes of Hp in the children in Guangzhou area and s1as1c/m2, cagA and iceA1 were the dominant genotypes combination of Hp in the children in this area.