Controlling the europium oxidation state in diopside through flux concentration.

This paper explores the connection between the H3BO3 flux concentration and the co-existence of Eu2+ and Eu3+ dopants within CaMgSi2O6 crystals (diopside). The samples were synthesised using a solid-state synthesis method under varying atmospheric conditions, including oxidative (air), neutral (N2), and reductive (H2/N2 mixture) environments. Additionally, some materials underwent chemical modification by partially substituting Si4+ with Al3+ ions acting as charge compensation defects stabilizing Eu3+ luminescence. Depending on the specific synthesis conditions, the materials predominantly displayed either the orange-red luminescence of Eu3+ (under oxidising conditions) or the blue luminescence of Eu2+; however, the comprehensive results confirmed the co-existence of Eu3+/Eu2+ luminescence in both cases. This work shows that varying flux concentrations added during synthesis significantly affect the relative strength of Eu2+ and Eu3+ emissions in a manner dependent on the synthesis atmosphere. The emission of Eu2+ increases with a higher flux concentration in materials synthesised under oxidative and neutral atmospheres independent of the chemical modification. In contrast, for materials obtained under a reductive atmosphere, the changes in the Eu3+ emission intensity depended on the presence or absence of Al3+ ions namely the increase of flux increased the Eu3+ intensity in the case of unmodified materials and decreased in the Al-modified ones. All observed effects were qualitatively explained considering the double role of the flux in the studied system, which besides facilitating the diffusion of chemical species during synthesis acts as a charge compensating agent by creating B'Si centres stabilizing Eu3+ emission.

The new method of ZnIn2S4 synthesis on the titania nanotubes substrate with enhanced stability and photoelectrochemical performance.

In this work, ZnIn2S4 layers were obtained on fluorine doped tin oxide (FTO) glass and TiO2 nanotubes (TiO2NT) using a hydrothermal process as photoanodes for photoelectrochemical (PEC) water splitting. Then, samples were annealed and the effect of the annealing temperature was investigated. Optimization of the deposition process and annealing of ZnIn2S4 layers made it possible to obtain an FTO-based material generating a photocurrent of 1.2 mA cm-2 at 1.62 V vs. RHE in a neutral medium. In contrast, the highest photocurrent in the neutral electrolyte obtained for the TiO2NT-based photoanode reached 0.5 mA cm-2 at 1.62 V vs. RHE. In addition, the use of a strongly acidic electrolyte allowed the generated photocurrent by the TiO2NT-based photoanode to increase to 3.02 mA cm-2 at 0.31 V vs. RHE. Despite a weaker photoresponse in neutral electrolyte than the optimized FTO-based photoanode, the use of TiO2NT as a substrate allowed for a significant increase in the photoanode's operating time. After 2 h of illumination, the photocurrent response of the TiO2NT-based photoanode was 0.21 mA cm-2, which was 42% of the initial value. In contrast, the FTO-based photoanode after the same time generated a photocurrent of 0.02 mA cm-2 which was only 1% of the initial value. The results indicated that the use of TiO2 nanotubes as a substrate for ZnIn2S4 deposition increases the photoanode's long-term stability in photoelectrochemical water splitting. The proposed charge transfer mechanism suggested that the heterojunction between ZnIn2S4 and TiO2 played an important role in improving the stability of the material by supporting charge separation.

Lanthanide ions (Eu3+, Er3+, Pr3+) as luminescence and charge carrier centers in Sr2TiO4.

A series of strontium orthotitanate (Sr2TiO4) samples doped with 2% of a mole of europium, praseodymium, and erbium were obtained using the solid-state synthesis method. The X-ray diffraction (XRD) technique confirms the phase purity of all samples and the lack of the influence of dopants at a given concentration on the structure of materials. The optical properties indicate, in the case of Sr2TiO4:Eu3+, two independent emission (PL) and excitation (PLE) spectra attributed to the Eu3+ ions at sites with different symmetries: low - excited at 360 nm and high - excited at 325 nm, while, for Sr2TiO4:Er3+ and Sr2TiO4:Pr3+, the emission spectra do not depend on the excitation wavelength. The measurements of X-ray photoemission spectroscopy (XPS) indicate the presence of only one type of charge compensation mechanism, which is based on the creation of strontium vacancies in all cases. This suggests that the different charge compensation mechanisms cannot easily explain the presence of Eu3+ at two non-equivalent crystal sites. The photocurrent excitation (PCE) spectroscopy investigations, that have not been reported in the literature so far, show that among all the studied dopants, only Pr3+ can promote the electrons to the conduction band and give rise to electron conductivity. The results collected from the PLE and PCE spectra allowed us to find the location of the ground states of lanthanides(II)/(III) in the studied matrix.

Nano Tin/Tin Oxide Attached onto Graphene Oxide Skeleton as a Fluorine Free Anode Material for Lithium-Ion Batteries.

Herein, we show a composite formation method of tin/tin oxide nanoparticles with graphene oxide and CMC based on laser ablation technique as an electrode material for energy storage devices. The material exhibited a three-dimensional conducting graphene oxide network decorated with tin or tin oxide nanoparticles. The structure, homogeneous distribution of nanoparticles, and direct contact between inorganic and organic parts were confirmed by scanning electron microscopy and high-resolution transmission electron spectroscopy. Electrochemical performances of composite electrode material showed a reversible capacity of 644 mAh/g at a current density equal to 35 mA/g, and 424 mAh/g at 140 mA/g. The capacity retention of 90% after 250 cycles show that tested electrode material is suitable as a negative electrode for lithium-ion batteries.

A content analysis of hand hygiene materials targeting elementary-age children.

Millions of dollars have been spent on the design and dissemination of educational materials to improve handwashing to prevent infectious diseases. School-age children have been the focus of many of these efforts; yet little is known about the content of these materials. This study uses content analysis to examine the theoretical and motivational trends as well as the communication approach used in a sample of hand hygiene intervention materials targeting elementary-age children. Two trained coders analyzed 144 communication materials. Study results indicate that educational materials infrequently exhibit information consistent with theories of communication for behavior change, commonly use fear-based messaging, and rarely recommend using technology in the design of the interventions. Implications for future research and the design of more strategic, child-focused hand hygiene interventions are discussed.

Mammalian cell defence mechanisms against the cytotoxicity of NaYF4:(Er,Yb,Gd) nanoparticles.

Water-soluble upconversion nanoparticles (UCNPs), based on polyvinylpyrrolidone (PVP)-coated NaYF4:Er3+,Yb3+,Gd3+, with various concentrations of Gd3+ ions and relatively high upconversion efficiencies, were synthesized. The internalization and cytotoxicity of the thus obtained UCNPs were evaluated in three cell lines (HeLa, HEK293 and astrocytes). No cytotoxicity was observed even at concentrations of UCNPs up to 50 µg ml-1. The fate of the UCNPs within the cells was studied by examining their upconversion emission spectra with confocal microscopy and confirming these observations with transmission electron microscopy. It was found that the cellular uptake of the UCNPs occurred primarily by clathrin-mediated endocytosis, whereas they were secreted from the cells via lysosomal exocytosis. The results of this study, focused on the mechanisms of the cellular uptake, localization and secretion of UCNPs, demonstrate, for the first time, the co-localization of UCNPs within discrete cell organelles.

Incidence and clinical relevance of RET proto-oncogene germline mutations in pheochromocytoma patients.

BACKGROUND: Autosomal dominant cancer syndrome--multiple endocrine neoplasia type 2 (MEN 2), may exist more often than expected in patients with pheochromocytoma. Germline mutations identified recently in MEN 2 can be revealed by genetic screening. OBJECTIVE: To evaluate the frequency of RET (rearranged during transfection) mutations in patients with pheochromocytoma. DESIGN AND METHODS: We genetically screened germline mutations in the RET proto-oncogene and clinically re-evaluated patients with pheochromocytoma. A pentagastrin test and other biochemical studies were performed in all patients. SETTING: Department of Internal Medicine and Hypertension, The Medical University of Warsaw, Warsaw, Poland and the Department of Nephrology and Hypertension, Albert Ludwigs University, Freiburg, Germany. PARTICIPANTS: Seventy seven unselected patients with pheochromocytoma (19 men, 58 women, mean age: 51.55 +/- 1.5 years; pheochromocytoma confirmed histopathologically) out of 162 diagnosed and treated in the years 1957-1998 in the Department of Internal Medicine and Hypertension in Warsaw, Poland. The other 85 patients did not respond to the written invitation. MAIN OUTCOME MEASURES: The finding of RET mutations and diagnosis of MEN 2 in patients with pheochromocytoma. RESULTS: Genetic testing revealed germline mutations in the RET proto-oncogene in six patients (7.8%). All carriers had mutation of exon 11, codon 634: TGC to CGC. In four patients with this mutation, medullary thyroid carcinoma (MIC) was diagnosed and in three cases, surgically treated. Biochemical parameters: parathormone 31.88 +/- 2.87 pg/ml, calcitonin: 0 min 0.23 +/- 0.14 ng/ml; 2 min 0.49 +/- 0.21 ng/ml; 5 min 0.48 +/- 0.21 ng/ml, metoxycatecholamines: 601.62 +/- 42.71 microg/24h, epinephrine: 1.94 +/- 0.17 microg/24h, norepinephrine 13.96 +/- 1.3 microg/24h, carcinoembryonic antigen (CEA) 9.94 +/- 4.3 ng/ml. Ambulatory blood pressure monitoring (ABPM): systolic blood pressure (SBP): 116 +/- 1.9 mmHg, diastolic blood pressure (DBP): 73.7 +/- 0.9 mmHg. Clinical, biochemical and imaging procedures did not reveal any recurrence of pheochromocytoma in the 77 patients studied. CONCLUSIONS: Patients with pheochromocytoma should be genetically screened for mutations of the RET proto-oncogene. These patients should undergo clinical screening for MEN 2. In addition, genetic studies can be useful for the screening of the families of the carriers.

Application of mechanical and manual sutures enclosing the bronchus.

The mechanical suture was introduced into thoracic surgical procedures by Amonosow and Androsow, Soviet surgeons, in the late 50s. The aim of the paper is to compare the incidence of bronchopleural fistulae that develop after the mechanical suture has been applied in bronchus surgery with the corresponding figures for traditional manual sutures. In the period of January 1997-March 1999 a series of 524 anatomical lung parenchyma resections was performed at the Department of Thoracic Surgery, Medical Academy of Gdansk. In 460 cases (87.8%) the indication for the procedure came from primary lung carcinoma, and in 64 cases (12.2%) from tuberculosis, hamartoma, arteriovenous fistula, inflammatory lesions, asperpilloma, and metastases to the lungs. Depending on the way the bronchus was surgically closed the patients were subgrouped as follows: group I comprised 209 subjects (40.6%) whose bronchus was closed with a mechanical TA Premium Auto Suture, and group II that embraced 306 subjects (59.4%) whose bronchus was closed with a manual PDS 3/0 or Maxon 3/0 suture. The bronchopleural fistula developed in 11 cases of which 5/216 (2.3%) had the bronchus stump closed with a mechanical suture, and 6/308 (2.0%) cases had it closed with a manual suture. Of 11 cases of bronchopleural fistula 10 cases were noted after pneumonectomy. After the right side pneumonectomy, one fistula was discovered following the application of mechanical suture and six fistulas were found when the manual suture was used. After the left side pneumonectomy, no fistulae were discovered when the manual suture was used, and 3 those found were exclusively present when the mechanical suture was applied.

Effects of the correction of renal artery stenosis on blood pressure, renal function and left ventricular morphology.

The aim of this study was to evaluate the effect of renal artery stenosis (RAS) correction in hypertensive patients on 24 h SBP, 24 h DBP, creatinine clearance (GFR), urinary albumin excretion (UAE) and LV morphology and mass (LVMI). A total of 61 hypertensive patients with RAS undergoing PTRA and/or surgical treatment entered the prospective study. The final analysis was done in 44 patients (age range 45.8 +/- 16.2 years) with RAS (atherosclerosis (ASC) 31 patients, fibromuscular dysplasia (FMD) 12 patients, arteritis 1 patient) who underwent PTRA (34 patients) or surgical treatment (10 patients) and presented no Doppler signs of restenosis (or a new stenosis) during 1-year observation. The pre-interventional assessment repeated after 6 and 12 months included ABPM, GFR, UAE and echocardiography. The results were analysed in the combined group (CG) and in according aetiology. 24 h SBP and 24 h DBP decreased in all groups 6 months post-intervention and did not change further. Cure of HT was observed in 35% and 29% of ASC patients at 6 and 12 months respectively; and in 58% of FMD patients. Failure rate at 12 months was 48% in ASC against 25% in FMD. The mean GFR in CG was higher 12 months after intervention. The increase in GFR was noted in 45% of patients, the decrease in 25% of patients at 12 months. Normal values of UAE were found in 71% of patients, pre- and post-intervention alike. Mean LVMI and number of patients with LVH in CG decreased already during the initial 6 months post-intervention and did not change further. In conclusion, correction of RAS leads to cure of or improved control of hypertension in the majority of the patients with FMD, but in the ASC group in about half of cases no BP cure or improvement was seen. The renal function was improved or stable in two-thirds of patients after revascularization. Successful renal revascularization was followed by regression of LVH, which was evident within 6 months post-intervention.

Radon awareness and reduction campaigns for African Americans: a theoretically based evaluation.

Radon gas is a significant health threat linked to thousands of preventable deaths each year. One population that may be at increased risk from harm from radon exposure is African Americans. However, little is known about what African Americans think or know about radon. A theoretically based evaluation of radon awareness and reduction campaigns was conducted with African Americans. The knowledge and perceptions results indicate that African Americans often hold inaccurate beliefs regarding radon (e.g., confusing it with carbon monoxide gas), perceive it to be a serious threat, and perceive recommended responses to be inadequate in averting harm. The campaign materials evaluation shows that campaign materials often promote perceptions of threat but not perceptions of efficacy regarding recommended responses. Recommendations are given for public health practitioners.

A theoretically based evaluation of HIV/AIDS prevention campaigns along the trans-Africa highway in Kenya.

Print HIV/AIDS prevention campaign materials (e.g., posters, pamphlets, stickers) from 10 public health organizations in Kenya were evaluated according to the Extended Parallel Process Model (EPPM), a health behavior change theory based on the fear appeal literature, at various sites along the Trans-Africa Highway in Kenya. Three groups each of commercial sex workers (CSWs), truck drivers (TDs) and their assistants (ASSTs), and young men (YM) who live and work at the truck stops participated in focus group discussions where reactions to the campaign materials were gathered according to this theoretical base. Reactions to campaign materials varied substantially, according to the poster or pamphlet viewed. Overall, most participants wanted more detailed information about (a) the proper way to use condoms, (b) ideas for how to negotiate condom use with reluctant partners, and (c) accurate information on symptoms of AIDS and what to do once one contracted HIV. Both quantitative and qualitative analyses of the campaign materials are reported.

Hemorrheological indices, catecholamines, neuropeptide Y and serotonin in patients with essential hypertension.

Hemorrheological and humoral abnormalities and excessive platelet activity can predict the development of cardiovascular complications in patients with essential hypertension. A study was conducted to assess the influence of gender on these factors and the interrelations between changes in hemorrheology and the sympatho-adrenal system in 54 patients (18 women, 36 men) with essential hypertension (aged 39.6 +/- 9.7 years) and 25 healthy volunteers (10 women, 15 men; aged 36.0 +/- 7.2 years). A decrease in erythrocyte deformability (p < 0.01) was found in the hypertensive men compared with the hypertensive women. Hematocrit (p < 0.01), blood viscosity at the shear rates of 0.3 s-1 (p < 0.01) and 6 s-1 (p < 0.01), plasma viscosity (p < 0.01), erythrocyte aggregation (p < 0.01), and neuropeptide Y (p < 0.02) concentrations were higher in the hypertensive men than in the hypertensive women. A positive correlation between blood fibrinogen and serotonin was found in the pooled hypertensive group and in the hypertensive men (p < 0.01) and between blood viscosity (shear rate 6 s-1) and neuropeptide Y in the pooled hypertensive group (p < 0.01). Neuropeptide Y correlated with filtration time of 1 mL blood in the hypertensive men (p < 0.05) and in the pooled normotensive group (p < 0.01) and with beta-thromboglobulin in the hypertensive women (p < 0.001). A positive correlation was also found in the hypertensive men between erythrocyte and platelet aggregation (p < 0.01) and between beta-thromboglobulin and adrenaline (p < 0.01). Hemorrheological and humoral abnormalities are more pronounced in men than in women with essential hypertension and may contribute to the increased incidence of cardiovascular events in men.

[Pheochromocytoma in a 81 year old woman treated with surgery--case report]. / Guz chromochlonny u 81. letniej chorej leczony operacyjnie--opis przypadku.

A case of pheochromocytoma in 81 year old woman hospitalized due to choledocholithiasis is reported. During premedication pronounced blood pressure elevation was observed. Operation was discontinued and diagnostic of pheochromocytoma was carried out. USG and CT scanning revealed right sided adrenal tumor. Elevated urine catecholamines and methoxycatecholamines were found. The patient underwent adrenalectomy and cholecystectomy. Histological examination confirmed diagnosis of pheochromocytoma. The patients done uneventful recovery.

[Evaluation of the usefulness for measuring catecholamines and their principle metabolites in the diagnosis of pheochromocytoma]. / Ocena przydatnosci oznaczania katecholamin i ich glównych metabolitów w diagnostyce guzów chromochlonnych.

Objective of the study was assessment of the usefulness of determination of noradrenaline (NA) and adrenaline (A) in urine and blood as well as the total methoxycatecholamines (MNA +MA), vanillylmandelic acid (VMA), DOPA and dopamine (DA) urinary excretion in diagnosis of pheochromocytoma. The experience based on 155 patients with pheochromocytoma (105F, 50M, age 18-82 yrs) diagnosed in the Department of Hypertension and Angiology Academy of Medicine in Warsaw will be discussed. In all patients excluding 2 cases pheochromocytoma has been proven histopathologically. The most considerable diagnostic usefulness of MNA + MA indication was proven. MNA + MA was increased in 96.6 patients. In 89.6% patients an increased excretion of NA and A or one of this catecholamines was demonstrated. An increased excretion of VMA was demonstrated in 75%. The excretion of DOPA and dopamine was tested in 120 cases. An increased excretion of DA was shown in 31% and DOPA in 16%.

Magnetic resonance imaging differentiation of adrenal masses at 1.5 T: T2-weighted images, chemical shift imaging, and Gd-DTPA dynamic studies.

The purpose of our study was to assess the potential role of spin-echo (SE), chemical shift, and gadolinium-enhanced magnetic resonance imaging (MRI) in the differentiation of adrenal masses. Seventy-two adrenal masses (26 nonhyperfunctioning adenomas, 16 aldosterone-secreting adenomas and 6 other different benign cortical masses, 18 pheochromocytomas, and 6 malignant masses) in 63 patients were evaluated with spin-echo sequences, chemical shift imaging (CSI) and gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA) dynamic studies. Ratios and indices of signal intensity for all examined MRI methods were calculated and examined for significance of difference between different types of adrenal masses. Quantitative magnetic resonance evaluation of adrenal masses showed significant differences (at least alpha < 0.01) between nonhyperfunctioning adenomas vs. pheochromocytomas or vs. malignant lesions or vs. aldosterone-secreting adenomas and between pheochromocytomas vs. malignant lesions. The most specific indicators of adrenal mass character proved to be the CSI ratio based on opposed-phase and in-phase two-dimensional fast low-angle shot (FLASH) images, reflecting lipid content in the lesion, and Gd-DTPA dynamic studies ratios reflecting contrast agent inflow and washout in the lesion: WoMAX/LAST and Dyn1.2-3.2. There was no overlap of CSI ratio between adenomas and pheochromocytomas. The overlap of ranges of CSI ratio between nonhyperfunctioning adenomas and aldosterone-secreting adenomas was only 18.5%. There was no overlap of WoMAX/LAST ratio between adenomas and pheochromocytomas, or adenomas and malignant lesions. The overlap of ranges of Dyn1.2-3.2 ratio between pheochromocytomas and malignant lesions was only 17.6%. MRI enables good visualization and specific characterization of adrenal masses. The optimal MRI protocol for the adrenal region is presented.

[Pheochromocytoma with hemorrhagic necrosis and rupture with symptoms of acute abdomen and shock]. / Pheochromocytoma--martwica krwotoczna i przerwanie guza z objawami ostrego brzucha i wstrzasem.

A case of a pheochromocytoma with haemorrhagic necrosis resulting in signs of acute abdomen with shock is reported. Diagnosis of a ruptured adrenal tumor was made by CT scanning. Elevated urine and plasma catecholamines as well as histological examination of the removed tumor confirmed the clinical suspicion of pheochromocytoma. The patient made uneventful recovery and is asymptomatic 2 years after surgery. Ruptured pheochromocytoma as a cause of abdominal emergency is discussed in view of the existing literature.

[Evaluation of blood rheology indices in patients with pheochromocytoma]. / Ocena wskazników reologicznych krwi u chorych z pheochromocytoma.

Investigated group consisted of 28 patients (21 female and 7 male) with pheochromocytoma in mean age of 39.9 +/- 13 years, while control group comprised 25 healthy volunteers in mean age 36.0 +/- 7.2 years. Following parameters were determined: plasma and blood viscosity, erythrocyte and platelets aggregation, erythrocyte deformability, hematocrit, beta-thromboglobulin plasma concentration, plasma fibrinogen concentration, lipids concentration, noradrenaline, adrenaline, serotonin, neuropeptide Y plasma concentrations. Plasma fibrinogen and beta-thromboglobulin were increased in pheochromocytoma before surgery after pharmacological treatment and also after excision of the tumor. Whereas altered erythrocyte deformability before any treatment, only. Plasma neuropeptide Y concentration was higher in pheochromocytoma before surgery and after pharmacological treatment. There was no correlation between plasma catecholamines, plasma fibrinogen, beta-thromboglobulin, and erythrocyte deformability. Our results suggest that rheological abnormalities observed in patients with pheochromocytoma may contribute to vascular complications in this subjects. Sympathetic nervous system seems to influence indirectly observed rheological abnormalities.