Dual state antiphase excitability in optically injected quantum dot lasers

info:eu-repo/semantics/publishe

Lasing state hysteresis in a two-state quantum dot laser via optical injection

info:eu-repo/semantics/publishe

Injection-induced, tunable, all-optical gating in a two-state quantum dot laser

We demonstrate a tunable all-optical gating phenomenon in a single-section quantum dot laser. The free-running operation of the device is emission from the excited state. Optical injection into the ground state of the material can induce a switch to emission from the ground state with complete suppression of the excited state. If the master laser is detuned from the ground-state emitting frequency, a periodic train of ground-state dropouts can be obtained. These dropouts act as gates for excited-state pulsations: during the dropout, the gate is opened and gain is made available for the excited state, and the gate is closed again when the dropout ends. Numerical simulations using a rate equation model are in excellent agreement with experimental results.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Toward Bright Red-Emissive Carbon Dots through Controlling Interaction among Surface Emission Centers

Relatively weak red photoluminescence of carbon dots (CDots) is a major challenge on the way to their successful implementation in biological and optoelectronic devices. We present a theoretical analysis of the interaction among the surface emission centers of CDots, showing that it may determine efficiency of the red photoluminescence of CDots. Based on the previous experimental studies, it is assumed that the optical response of the CDots is determined by the molecule-like subunits of polycyclic aromatic hydrocarbons (PAHs) attached to the CDots surface. Three characteristic types of coupling of these PAH subunits are considered: non-interacting monomers, noncovalently bound dimers, and covalently bound dimers with two, three, or four carbon linkers. We demonstrate that the CDots photoluminescence broadens, redshifts, and weakens by 2 orders of magnitude when the free monomers are substituted by the covalently bridged centers. These and other results of our study show that the realization of CDots with many weakly interacting surface emission centers may constitute an efficient way to achieve their efficient red photoluminescence, which is highly desirable for biological and optoelectronic applications

Assessment of Bowel Preparation Using Low-Volume Sulphate-Based Preparations in Comparison with Macrogols: A Multicenter, Randomized, Comparative Clinical Study of the 3rd Phase

Oral sulphate solution (OSS: sodium sulphate, potassium sulphate and magnesium sulphate) is a low-volume osmotic agent for cleansing the intestines.Aim: in a multicentre, prospective, randomized, 3rd phase study with two parallel groups, the effectiveness, safety and tolerability of OSS was evaluated in comparison with Macrogol 4000 with electrolytes (a reference preparation for bowel cleansing in Russia) in adult patients who were scheduled for routine diagnostic colonoscopy.Methods. This study was conducted in three Russian research centres during the March–December, 2015 period. Men and women over the age of 18 scheduled to undergo routine diagnostic colonoscopy were randomly assigned either to the OSS group or to the Macrogol group with a fractional use mode before the colonoscopy. The colonoscopy researchers were not aware of which preparation had been taken by the patients. Anonymized video records were centrally analysed by three experts. The primary end point was the proportion of patients with a successful bowel preparation for colonoscopy ≥6 points, as determined by the Boston Bowel Preparation Scale of quality assessment (BBPS scale).Results. 296 patients were randomized in the study (147 patients were treated with OSS, 149 patients received Macrogol); 294 participants were included in the Intention to Treat population (ITT-population), and 274 participants were included in the population of patients who completed the study according to the protocol (Per-Protocol; PP-population) (139 patients received OSS, 135 patients received Macrogol). The proportion of patients with a successful bowel preparation (BBPS ≥6 scores) was high in both groups (OSS [PP-population]: 97.2 % (95 % confidence interval [CI] 89.5–99.3), Macrogol [PP-population]: 97.7 % (95 % CI: 90.7–99.4)). The corrected difference between the groups was -0.5 % (95 % CI: -4.2–3.3), thereby demonstrating “no less effective” of OSS as compared to Macrogol. Compliance with the drug use regime was higher in the OSS group than in the Macrogol group (95.7 % versus 82.3 %, respectively, p-value = 0.0011, ITT-population).The most common symptom reported in patients was nausea (27.9 % in the OSS group and 12.9 % in the Macrogol group). The proportion of patients who developed nausea was significantly higher in the OSS group than in the Macrogol group (25.2 % compared with 10.2 % when taking the first dose of the preparation (p = 0.0008) and 19.7 % compared with 6.8 % when taking the second dose of the preparation (p = 0.0016)). Differences in other symptoms (bloating, abdominal pain or abdominal discomfort) between the groups were not significant, with the severity of symptoms being generally mild. The safety profile of the investigated preparations in patients with inflammatory bowel disease (IBD) in remission did not differ from that in the general patient population.The differences in terms of secondary endpoints were not identified, including BBPS assessment for different sections of the colon, the level of polyp detection, the duration and completeness of colonoscopy, and the investigator’s satisfaction with the procedure. The analysis by subgroups also did not reveal any significant differences.Conclusion. In this study, the “not less effectiveness” of the sulphate solution was demonstrated as compared to Macrogol in a fractional use mode. Both preparations were well tolerated. Despite the higher incidence of nausea in the OSS group, the patients showed significantly higher compliance with the OSS mode as compared to that of Macrogol.This study is registered with the ClinicalTrials.gov Registry of Clinical Trials, No. NCT02321462

Assessment of Bowel Preparation Using Low-Volume Sulphate-Based Preparations in Comparison with Macrogols: A Multicenter, Randomized, Comparative Clinical Study of the 3rd Phase

Oral sulphate solution (OSS: sodium sulphate, potassium sulphate and magnesium sulphate) is a low-volume osmotic agent for cleansing the intestines.Aim: in a multicentre, prospective, randomized, 3rd phase study with two parallel groups, the effectiveness, safety and tolerability of OSS was evaluated in comparison with Macrogol 4000 with electrolytes (a reference preparation for bowel cleansing in Russia) in adult patients who were scheduled for routine diagnostic colonoscopy.Methods. This study was conducted in three Russian research centres during the March–December, 2015 period. Men and women over the age of 18 scheduled to undergo routine diagnostic colonoscopy were randomly assigned either to the OSS group or to the Macrogol group with a fractional use mode before the colonoscopy. The colonoscopy researchers were not aware of which preparation had been taken by the patients. Anonymized video records were centrally analysed by three experts. The primary end point was the proportion of patients with a successful bowel preparation for colonoscopy ≥6 points, as determined by the Boston Bowel Preparation Scale of quality assessment (BBPS scale).Results. 296 patients were randomized in the study (147 patients were treated with OSS, 149 patients received Macrogol); 294 participants were included in the Intention to Treat population (ITT-population), and 274 participants were included in the population of patients who completed the study according to the protocol (Per-Protocol; PP-population) (139 patients received OSS, 135 patients received Macrogol). The proportion of patients with a successful bowel preparation (BBPS ≥6 scores) was high in both groups (OSS [PP-population]: 97.2 % (95 % confidence interval [CI] 89.5–99.3), Macrogol [PP-population]: 97.7 % (95 % CI: 90.7–99.4)). The corrected difference between the groups was -0.5 % (95 % CI: -4.2–3.3), thereby demonstrating “no less effective” of OSS as compared to Macrogol. Compliance with the drug use regime was higher in the OSS group than in the Macrogol group (95.7 % versus 82.3 %, respectively, p-value = 0.0011, ITT-population).The most common symptom reported in patients was nausea (27.9 % in the OSS group and 12.9 % in the Macrogol group). The proportion of patients who developed nausea was significantly higher in the OSS group than in the Macrogol group (25.2 % compared with 10.2 % when taking the first dose of the preparation (p = 0.0008) and 19.7 % compared with 6.8 % when taking the second dose of the preparation (p = 0.0016)). Differences in other symptoms (bloating, abdominal pain or abdominal discomfort) between the groups were not significant, with the severity of symptoms being generally mild. The safety profile of the investigated preparations in patients with inflammatory bowel disease (IBD) in remission did not differ from that in the general patient population.The differences in terms of secondary endpoints were not identified, including BBPS assessment for different sections of the colon, the level of polyp detection, the duration and completeness of colonoscopy, and the investigator’s satisfaction with the procedure. The analysis by subgroups also did not reveal any significant differences.Conclusion. In this study, the “not less effectiveness” of the sulphate solution was demonstrated as compared to Macrogol in a fractional use mode. Both preparations were well tolerated. Despite the higher incidence of nausea in the OSS group, the patients showed significantly higher compliance with the OSS mode as compared to that of Macrogol.This study is registered with the ClinicalTrials.gov Registry of Clinical Trials, No. NCT02321462

Relationship between the Levels of lncRNA H19 in Plasma and Different Adipose Tissue Depots with Patients’ Response to Bariatric Surgery

Bariatric surgery represents a widespread approach to treating morbid obesity. The search for biomarkers to identify patients to whom this type of treatment will be most effective is needed. Our aim was to characterize the relationship of levels of lncRNA H19 in plasma and different adipose tissue depots with patients’ response to bariatric surgery. The study includes control subjects, patients with obesity and patients with obesity accompanied by impaired carbohydrate metabolism (ICM). Quantitative analysis of lncRNA H19 levels has been performed using qPCR in plasma and subcutaneous (SAT) and visceral adipose tissue (VAT). Patients with obesity without ICM have higher levels of lncRNA H19 in VAT compared to SAT, and higher levels of lncRNA H19 in SAT compared to SAT of control individuals. One year after the intervention, levels of lncRNA H19 decreased in SAT of patients with obesity without ICM. The preoperative level of lncRNA H19 in VAT demonstrates a positive correlation with excess weight loss and a negative correlation with initial BMI. In conclusion, ICM affects expression of lncRNA H19 in SAT of patients with obesity. The preoperative level of lncRNA H19 in VAT can be used to predict excess weight loss in patients with obesity after bariatric surgery