Optical spectroscopy of single beryllium acceptors in GaAs/AlGaAs quantum well

We carry out microphotoluminescence measurements of an acceptor-bound exciton (A^0X) recombination in the applied magnetic field with a single impurity resolution. In order to describe the obtained spectra we develop a theoretical model taking into account a quantum well (QW) confinement, an electron-hole and hole-hole exchange interaction. By means of fitting the measured data with the model we are able to study the fine structure of individual acceptors inside the QW. The good agreement between our experiments and the model indicates that we observe single acceptors in a pure two-dimensional environment whose states are unstrained in the QW plain

Chronic Pulmonary Aspergillosis: Literature Review and Demonstration of Own Observations

Chronic pulmonary aspergillosis (CPA) is a severe disease that develops mainly in patients without obvious immune disorders. Computed tomography is the main instrumental method in the diagnosis of CPA, which is necessary to determine the form of the disease, to choose treatment policy, to combat complications, and to monitor therapy. This makes it important for a radiologist to understand the main aspects of timely and differential diagnosis. There are insufficient Russian studies on this problem. This paper analyzes the 2014–2020 Russian and foreign publications available in PubMed, Web of Science, Elsevier, and eLibrary electronic databases. When searching for information, the following keywords were used: “computed tomography”, “chronic pulmonary aspergillosis”, “aspergilloma”, “air-crescent symptom”, “differential diagnosis”

Possibilities of Discriminant Analysis in the Differential Diagnosis of Chronic Aspergillosis and Nonmicotic Lung Lesions

Objective: to improve the efficiency of differential diagnosis of chronic pulmonary aspergillosis (СPA) based on the assessment of its probability using a discriminant mathematical model. Material and methods. The prospective study included 74 patients with CPA (57% women, median age 53 years) meeting the ERS/ESCMID criteria (2016). The control group consisted of 35 patients with lung diseases without CPA. Clinical and anamnestic data, the results of computed tomography (CT), laboratory and instrumental methods of research were analysed. By means of stepwise discriminant analysis, the model was created in order to differentiate compared groups. Results. The main forms of CPA were simple solitary aspergilloma (n = 30, 40%) and cavitary CPA (n = 21, 28%). On CT scans, in patients with CPA pulmonary emphysema (n = 50, 74%; 95% CI 63–83), bronchiectasis (n = 42, 56%; 95% CI 44–67), pleura thickening (n = 40, 56%; 95% CI 42–65) were detected with a high frequency. The sensitivity and specificity of typical for CPA air sickle symptom were 66.2% and 74.29%, respectively. The diagnostic informativeness of laboratory methods was characterized by high specificity (85–100%), however, it had sensitivity 40–60%. A discriminant model was worked up. It included five variables: mycological confirmation of the diagnosis (р < 0.001), air sickle symptom on CT (p = 0.03), ground glass opacity sympton on CT (p = 0.017), accompanying rheumatological diseases (p = 0,031), positive Aspergillus antigen in bronchoalveolar lavage (p = 0.036). The resulting model of differential diagnosis is statistically significant (F = (5.102) = 27.291; p < 0.001). Conclusion. CT-patterns of CPA include typical (air sickle symptom) and nonspecific (pleura thickening, emphysema, bronchiectasis) changes. Separately taken laboratory indicators and CT-symptoms are not always the determining criteria for diagnosis; an integrated approach is required to make a diagnosis. The proposed model improves the accuracy of differential diagnosis between CPA and nonmycotic lung diseases: increases sensitivity to 82.43%, specificity to 94.28% in comparison with separately analyzed laboratory data and typical CT-pattern of air sickle symptom. As a whole this model allows to classify the CPA and nonmycotic lung disease in 86,23% of cases

Resource-efficient low-loss four-channel active demultiplexer for single photons

We report a design and implementation of a resource-efficient spatial demultiplexer which produces 4 indistinguishable photons with efficiency of 39.7% per channel. Our scheme is based on a free-space storage/delay line which accumulates 4 photons and releases them by a controlled polarization rotation using a single Pockels cell.Comment: 8 pages, 7 figure

DIAGNOSTIC MARKERS OF ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS IN PATIENTS WITH BRONCHIAL ASTHMA

Studies of probable significance of different immunological mediators for the development of chronic allergic inflammation in patients with allergic bronchopulmonary aspergillosis (ABPA) are necessary in order to specify potential targets for therapeutic intervention and timely diagnosis of the disease. The purpose of present study was to determine the features of immune response regulation, and to identify diagnostic markers associated with development of ABPA in patients with bronchial asthma, and to evaluate clinical and immunological efficacy of specific antimycotic therapy.The study involved 13 patients with ABPA, 14 patients with bronchial asthma with fungal sensitization (BAFS), 17 patients with bronchial asthma (BA) and 12 apparently healthy individuals. Levels of thymic stromal lymphopoietin (TSLP), thymus and activation-regulated chemokine (TARC), IL-8, as well as levels of total IgE and specific IgE to Aspergillus fumigatus (A. fumigatus) were measured in blood serum by enzyme immunoassay; blood eosinophil counts were also made. Monitoring of these immunological markers in the course of antimycotic therapy was carried out.Significantly higher numbers of eosinophils, increased levels of total IgE and sIgE for A. fumigatus, as well as TARC and IL-8 in serum were revealed in patients with ABPA when compared to the patients with BA. No significant differences in TSLP content were found between the examined groups of patients. A positive correlation between the levels of sIgE to A. fumigatus and contents of TARC and IL-8, numbers of eosinophils, and total IgE levels confirms the important diagnostic value of proinflammatory cytokines in ABPA patients. In the course of itraconazole medication, a positive clinical and immunological dynamics in ABPA patients was revealed. After 12 weeks of therapy, a significant increase in AST, FEV1 and Tiffno respiratory indexes, along with decreased number of eosinophils, total IgE levels, and a trend towards a decrease in TARC and IL-8 levels were documented. This dynamics confirms clinical efficiency of antifungal drugs when treating chronic allergic inflammation in ABPA patients.Implementation of modern immunological biomarkers, alongside with traditional indicators, will allow to differentially evaluate a probability for ABLA development in patients with bronchial asthma, to present additional evidence for discerning early stages of the disease, and to conclude about the efficiency of the therapy applied

How to: interpret MICs of antifungal compounds according to the revised clinical breakpoints v. 10.0 European committee on antimicrobial susceptibility testing (EUCAST)

BACKGROUND: EUCAST has revised the definition of the susceptibility category "I" from "Intermediate" to "Susceptible, Increased exposure". This implies that "I" can be used where the drug-concentration at the site of infection is high, either because of dose escalation or through other means to ensure efficacy. Consequently, "I" is no longer used as a buffer-zone to prevent technical fact