Interlayer excitons in MoSe2/2D perovskite hybrid heterostructures - the interplay between charge and energy transfer.

van der Waals crystals have opened a new and exciting chapter in heterostructure research, removing the lattice matching constraint characteristics of epitaxial semiconductors. They provide unprecedented flexibility for heterostructure design. Combining two-dimensional (2D) perovskites with other 2D materials, in particular transition metal dichalcogenides (TMDs), has recently emerged as an intriguing way to design hybrid opto-electronic devices. However, the excitation transfer mechanism between the layers (charge or energy transfer) remains to be elucidated. Here, we investigate PEA2PbI4/MoSe2 and (BA)2PbI4/MoSe2 heterostructures by combining optical spectroscopy and density functional theory (DFT) calculations. We show that band alignment facilitates charge transfer. Namely, holes are transferred from TMDs to 2D perovskites, while the electron transfer is blocked, resulting in the formation of interlayer excitons. Moreover, we show that the energy transfer mechanism can be turned on by an appropriate alignment of the excitonic states, providing a rule of thumb for the deterministic control of the excitation transfer mechanism in TMD/2D-perovskite heterostructures.

Correction factors for determination of annual average radon concentration in dwellings of Poland resulting from seasonal variability of indoor radon.

The method for the calculation of correction factors is presented, which can be used for the assessment of the mean annual radon concentration on the basis of 1-month or 3-month indoor measurements. Annual radon concentration is an essential value for the determination of the annual dose due to radon inhalation. The measurements have been carried out in 132 houses in Poland over a period of one year. The passive method of track detectors with CR-39 foil was applied. Four thermal-precipitation regions in Poland were established and correction factors were calculated for each region, separately for houses with and without basements.

Epithelial bone marrow cells in patients with advanced esophageal squamous cell carcinoma.

The aim of the current study was to examine epithelial cells in the bone marrow and peripheral blood of patients with various stages of esophageal squamous cell cancer prior to surgical treatment and to analyze the prognostic significance of these carcinoma cells deposits to the stage of the disease and applied surgical therapy. Thirty-two patients (25 men and 7 women), and 5 healthy bone marrow donors serving as controls were studied. Bone marrow samples were evaluated by light microscopy and examined by flow cytofluorometry. Cells were phenotypically analyzed for the antigens CD45- and CD18+ and/or EMA+. Results are presented as the number of cells revealing the investigated phenotype per 10 (5)analyzed cells. CD18 was expressed in the bone marrow cells of 15 of the 32 (47%) patients and EMA in 20/32 (62%), but not in peripheral blood. In 13 of the 32 pts (41%), co-expression of CD18 and EMA was observed. Patients with the proportion of marrow erythroblasts below 15% had higher numbers of CD18+ and EMA+ cells and there was a negative correlation between the number of erythroblasts and EMA+ cells (r=0.54, p=0.01). In patients with esophageal cancer and anemia, the number of EMA+ cells was higher (p=0.05) and the percentage of erythropoietic cells in the bone marrow was lower (p=0.01). In conclusion, flow cytofluorometry using anti-cytokeratin and anti-EMA antibodies may be useful in evaluating microdeposits of esophageal squamous cells in bone marrow. A dysfunctioning erythropoietic system causing anemia can be a first signal for the presence of malignant cell microdeposits in the marrow of patients with esophageal carcinoma.

Human red blood cells' physiological water exchange with the plasma.

In the present paper, fundamental issues related to the mechanisms of human red blood cells' physiological water exchange with the plasma (for the stationary conditions) have been discussed. It has been demonstrated, on the basis of mechanistic transport equations for membrane transport that red blood cells are capable of exchanging considerable amounts of water with the plasma. Water absorption is osmosis-driven, and its removal occurs according to the hydromechanics principle, i.e. is driven by the turgor pressure of red blood cells. This newly-acquired knowledge of these issues may appear highly useful for clinical diagnosis of blood diseases and blood circulation failures.

Surgical treatment of patients with multiple carcinomas.

BACKGROUND: Primary multiple carcinomas are not observed very frequently. Research has been focused mainly on such issues as the frequency of occurrence of primary multiple carcinomas, the identification of high-risk groups, early diagnosis, treatment methods, and prognosis. The purpose of this article is to present our own experience in the surgical treatment of patients with multiple cancers. MATERIAL AND METHODS: The paper presents 13 patients of both sexes with primary multiple carcinomas. Four of these patients were diagnosed with synchronous carcinomas, the remaining patients with metachronous. The malignant tumors were variously localized. In the group with synchronous carcinomas, the malignant tumors were located in esophagus, stomach and rectum, pancreas and right ovary, esophagus and palatine tonsil. In the group with metachronous carcinomas, another cancer was diagnosed 12 months to 24 years after the treatment of the first carcinoma was completed. The other cancers were located in esophagus, stomach, pancreas, lung, and the skin of the cheek. Nine patients were qualified for surgical treatment on the basis of the preoperative TNM classification. Various surgical procedures were used. In cases of synchronous multiple carcinomas one-stage operations were preferred. RESULTS: Significant postoperative complications were noted in 2 cases. In the first case, a recto-sigmoid anastomotic leak resulted in increased circulatory and renal insufficiency, leading to the patient's decease. In the second case, a massive gastric hemorrhage after ileocoloesophagoplasty led to respiratory insufficiency, which was the cause of the patient's decease. Two patients died within 12 months after surgical treatment. In the first case cancer recurrence was the cause of death; in the second, myocardial infarction. Long-term follow-up was focused on 5 patients with no cancer recurrence during the period from 12 months to 4 years after surgical treatment. CONCLUSIONS: The results of this study suggest that patients who have had a first cancer successfully treated are at higher risk of developing a subsequent cancer, and that regular follow-up with thorough examination in patients successfully treated for cancer may lead to the early detection of a subsequent cancer when it is still at a curable stage.

Indoor radon concentrations in Poland as determined in short-term (two-day) measurements.

The aim of the present work was to obtain a pattern of 222Rn concentration distributions in typical buildings in Poland. In the investigations, the environmental passive detectors of the PICO-RAD type were used. The study encompassed buildings that were typical for Poland. The distribution of airborne 222Rn concentrations indoors is of a log-normal type. A total 1171 detectors were measured. Measurements were made in 319 basements, the remaining 852 measurements were carried out in the inhabited part of the houses. The radon concentrations in the basements in Bq x m(-3) ranged from 6 to 1300 with the arithmetic mean AM = 60, geometric mean GM = 30 and median M = 28, whereas those in the inhabited parts of the house (above the ground level) were: AM = 25, GM = 17 and M = 16 with the highest record value of 420.

[Vesicoureteral refluxes in children during the first two years of life]. / Odplywy pecherzowo-moczowodowe u dzieci w pierwszych dwóch latach zycia.

Ninety-six children with vesicoureteral reflux (VUR) diagnosed by age 2 were studied. The most common indication for radiological visualization of the urinary tract was a urinary tract infection (UTI). Among 143 cases of VUR, 51% were unilateral and 49% were bilateral. Other urinary tract abnormalities coexisted with VUR in 14.6% of children. Abnormal USG result was found in 24% of children, including only 13.4% with VUR and other urinary tract abnormalities. Conservative treatment was chosen in 126 (88%) cases of VUR in 87.5% of children. Follow-up voiding cystourethrography was performed in 60.7% of children. Conservative treatment was successful in 68.6% of children. VUR disappeared in 70.9% of cases after mean follow-up of 13.7 months (including 76.2% cases of VUR grade II, 54.5% cases of VUR grade III and 50% cases of VUR grade I). Recurrent UTI and lack of improvement after conservative treatment were indications for surgical treatment in 9.8% of children. Recurrent UTI were observed in 15.6% of children (including 16.7% among those treated conservatively and 8.3% among those treated surgically) and their course was febrile in most cases.

Study of 222Rn concentrations in drinking water in the north-eastern hydroregions of Poland.

This paper presents the results of radon concentration measurements in the drinking water from the municipal water supply system and private wells located in the north-eastern part of Poland. The measurements were carried out on 643 samples using a liquid scintillation method. The mean value was found to be 5262 Bq m-3 with a maximum of 38347 Bq m-3. The samples were obtained from different water-bearing levels, i.e. surface water, deep borehole water and well water and have respective mean values of 3398, 5178 and 6155 Bq m-3. In 57 water samples, a guideline maximum level of 11,000 Bq m-3 was found to be exceeded. The observed radon concentration in water can contribute to a 2% increase in indoor radon concentration.

Antioxidative activity of rosemary extract in lipid fraction of minced meat balls during storage in a freezer.

The influence of ethanol rosemary extract on lipid fraction of minced meat balls during storage in the freezer was studied. The quality of stored products was evaluated sensorically by the scale method and profiling of taste and aroma. Oxidative changes were investigated on the base of the changes in malonaldehyde content. It was observed that the addition of rosemary extract delayed the oxidation of lipid fraction of products. The antioxidative effect was related to the concentration of this extract in the product. The sensory changes and their intensity in products during storage depended on the amount of the extract added and the time of storage. The addition of the extract delayed the appearance of rancid taste in products.