Novel Quaternary Dilute Magnetic Semiconductor (Ga,Mn)(Bi,As): Magnetic and Magneto-Transport Investigations

Magnetic and magneto-transport properties of thin layers of the (Ga,Mn)(Bi,As) quaternary dilute magnetic semiconductor grown by the low-temperature molecular-beam epitaxy technique on GaAs substrates have been investigated. Ferromagnetic Curie temperature and magneto-crystalline anisotropy of the layers have been examined by using magneto-optical Kerr effect magnetometry and low-temperature magneto-transport measurements. Postgrowth annealing treatment has been shown to enhance the hole concentration and Curie temperature in the layers. Significant increase in the magnitude of magnetotransport effects caused by incorporation of a small amount of Bi into the (Ga,Mn)As layers revealed in the planar Hall effect (PHE) measurements, is interpreted as a result of enhanced spin-orbit coupling in the (Ga,Mn)(Bi,As) layers. Two-state behaviour of the planar Hall resistance at zero magnetic field provides its usefulness for applications in nonvolatile memory devices.Comment: 10 pages, 3 figures, to be published in the Proceedings of ICSM-2016 conferenc

The truncated moment problem on N0

We find necessary and sufficient conditions for the existence of a probability measure on N0, the nonnegative integers, whose first n mo- ments are a given n-tuple of nonnegative real numbers. The results, based on finding an optimal polynomial of degree n which is nonneg- ative on N0 (and which depends on the moments), and requiring that its expectation be nonnegative, generalize previous results known for n = 1, n = 2 (the Percus-Yamada condition), and partially for n = 3. The conditions for realizability are given explicitly for n ≤ 5 and in a finitely computable form for n ≥ 6. We also find, for all n, explicit bounds, in terms of the moments, whose satisfaction is enough to guarantee realizability. Analogous results are given for the truncated moment problem on an infinite discrete semi-bounded subset of R

The truncated moment problem on N0

We find necessary and sufficient conditions for the existence of a probability measure on N0, the nonnegative integers, whose first n moments are a given n-tuple of nonnegative real numbers. The results, based on finding an optimal polynomial of degree n which is nonnegative on N0 (and which depends on the moments), and requiring that its expectation be nonnegative, generalize previous results known for n=1, n=2 (the Percus–Yamada condition), and partially for n=3. The conditions for realizability are given explicitly for n≤5 and in a finitely computable form for n≥6. We also find, for all n, explicit bounds, in terms of the moments, whose satisfaction is enough to guarantee realizability. Analogous results are given for the truncated moment problem on an infinite discrete semi-bounded subset of R

An attempt to estimate the minimal number of Poles infected and treated for malaria in Poland and abroad

Background: Malaria is one of the three most dangerous infectious diseases in the world. According to official statistics, there are a few dozen cases in Poland annually while the number of Poles treated abroad or self-treating remains unknown. Poland has been declared to be malaria-free since 1963 and nowadays all cases are imported. The aim of the study is to determine the minimal number of malaria cases in Poles at home and abroad in the last decade. Materials and methods: The medical records of 4,710 patients tested for malaria in the Department of Tropical Parasitology in the years 2003–2012 were analysed. Two spreadsheets were created, which only included people with a history of malaria diagnosed in the reference centre where indirect immunofluorescent-antibody assay (IFA) for Plasmodium falciparum antigen proved positive. The minimum number of Poles who have had malaria at home and abroad was calculated on the basis of positive IFA results; the rate of all treated malaria patients in Poland in relation to those treated in the reference centre and the actual number of Poles with malaria diagnosed at home was calculated. Results: A group of 376 people with positive serologic tests results in indirect immunofluorescent antibody assay with titre ≥ 1:20 were received, including 227 patients with positive serologic results with titre ≥ 1:80. The rate of the overall number of malaria cases in Poland compared to the number of malaria cases in the University Centre for Maritime and Tropical Medicine Hospital was determined as 3.47:1. It was demonstrated that every year at least 174 to 211 Poles staying abroad may suffer from malaria. Conclusions: This is the first attempt to estimate the minimal number of Poles infected and treated for malaria in Poland and abroad. The estimated number is 8–10 times greater than the number of registered cases in Poland.

Different serotypes of dengue virus (DENV) imported by Polish travellers from dengue endemic areas to Poland

Background: Dengue viruses are the most widespread arboviruses (transmitted mainly by Aedes aegypti and Ae. albopictus mosquitoes), which have shown an unexpected geographic expansion. There are four dengue virus serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. Subsequent infections increase the risk of developing severe dengue fever. Materials and methods: Samples from travellers returning from the endemic area of dengue fever were examined with the reverse transcription-polymerase chain reaction method. Primers amplified 743 bp fragment of the NS5 and 3’UTR genomic region of mosquito-borne flaviviruses of JEV group were used. Results: The sequences from the 10 examined patients were compared to available DENV sequences in GenBank database and the basic local alignment search tool (BLAST) results confirmed that the infective virus was DENV-1 (6 patients), DENV-2 (2 patients) and DENV-3 (2 patients). Conclusions: For the first time in Poland, dengue virus serotypes were determined in travellers returning from dengue-endemic areas

Von Neumann equations with time-dependent Hamiltonians and supersymmetric quantum mechanics

Starting with a time-independent Hamiltonian $h$ and an appropriately chosen solution of the von Neumann equation $i\dot\rho(t)=[ h,\rho(t)]$ we construct its binary-Darboux partner $h_1(t)$ and an exact scattering solution of $i\dot\rho_1(t)=[h_1(t),\rho_1(t)]$ where $h_1(t)$ is time-dependent and not isospectral to $h$. The method is analogous to supersymmetric quantum mechanics but is based on a different version of a Darboux transformation. We illustrate the technique by the example where $h$ corresponds to a 1-D harmonic oscillator. The resulting $h_1(t)$ represents a scattering of a soliton-like pulse on a three-level system.Comment: revtex, 3 eps file

The statement of the Polish Society of Allergology experts on the treatment of difficult-to-treat asthma

The main objective of asthma treatment is to control symptoms of the disease; however, despite the availability of guidelines and many groups of medications, the degree of control of this condition is insufficient. In difficult-to-treat asthma, the optimal control cannot be achieved due to reasons independent of the disease. Factors worsening asthma control include: inadequate treatment plan (low therapy adherence and compliance), inappropriate inhalation technique, insufficient symptom control using the available classes of medications, incomplete response to treatment (non-responders, steroid-resistance), incorrect diagnosis of asthma or comorbidities, and environmental factors. In order to achieve the optimal asthma control, it is recommended to: take therapeutic decisions with the patient, assess the probability of non-compliance, perform detailed diagnostics and initiate treatment of concomitant diseases, carry out differential diagnosis of conditions mimicking asthma, educate the patient as to the inhalation technique and check it, eliminate unfavourable environmental factors, and modify current treatment. New treatment options for patients with asthma include: ultra-long-acting beta2-agonists, long-acting muscarine receptor antagonists (LAMA), monoclonal antibodies, and non-pharmacological interventions. The only LAMA approved for treatment of asthma is tiotropium bromide. The analyses performed demonstrated a high efficacy of tiotropium in terms of improved lung function parameters and prolonged time to the first asthma exacerbation. It is recommended as an add-on therapy at asthma treatment steps 4 and 5 according to GINA (Global Initiative for Asthma) 2014. The optimal asthma control is important from the medical as well as the economical point of view.The main objective of asthma treatment is to control symptoms of the disease; however, despite the availability of guidelines and many groups of medications, the degree of control of this condition is insufficient. In difficult-to-treat asthma, the optimal control cannot be achieved due to reasons independent of the disease. Factors worsening asthma control include: inadequate treatment plan (low therapy adherence and compliance), inappropriate inhalation technique, insufficient symptom control using the available classes of medications, incomplete response to treatment (non-responders, steroid-resistance), incorrect diagnosis of asthma or comorbidities, and environmental factors. In order to achieve the optimal asthma control, it is recommended to: take therapeutic decisions with the patient, assess the probability of non-compliance, perform detailed diagnostics and initiate treatment of concomitant diseases, carry out differential diagnosis of conditions mimicking asthma, educate the patient as to the inhalation technique and check it, eliminate unfavourable environmental factors, and modify current treatment. New treatment options for patients with asthma include: ultra-long-acting beta2-agonists, long-acting muscarine receptor antagonists (LAMA), monoclonal antibodies, and non-pharmacological interventions. The only LAMA approved for treatment of asthma is tiotropium bromide. The analyses performed demonstrated a high efficacy of tiotropium in terms of improved lung function parameters and prolonged time to the first asthma exacerbation. It is recommended as an add-on therapy at asthma treatment steps 4 and 5 according to GINA (Global Initiative for Asthma) 2014. The optimal asthma control is important from the medical as well as the economical point of view

Investigations on the occurrence of Plasmodium knowlesi in travellers returning from the endemic areas of simian malaria

Malaria remains an important public health issue all over the world. Among 5 Plasmodium species invasive to humans, Plasmodium knowlesi has been identified most recently. It is sometimes difficult to differentiate this species from P. malariae with the use of microscopic examination. However, P. knowlesi infection may be associated with rapidly increasing parasitaemia and severe clinical course with the risk of death. Samples from Polish travellers returning from areas where simian malaria is endemic were examined with the use of polymerase chain reaction (PCR). The small subunit of ribosomal RNA (SSU rRNA) genes was subjected to analysis using nested PCR reaction. No positive results of P. knowlesi were obtained. Due to morphological similarities to P. malariae, potentially severe clinical course of infection and P. knowlesi endemic regions being a common tourist destination, diagnostic and clinical vigilance is necessary, including molecular methods use for precise parasite identification