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Iridium Corroles Exhibit Weak Near-Infrared Phosphorescence but Efficiently Sensitize Singlet Oxygen Formation.
Six-coordinate iridium(III) triarylcorrole derivatives, Ir[TpXPC)]L2, where TpXPC = tris(para-X-phenyl)corrole (X = CF3, H, Me, and OCH3) and L = pyridine (py), trimethylamine (tma), isoquinoline (isoq), 4-dimethylaminopyridine (dmap), and 4-picolinic acid (4pa), have been examined, with a view to identifying axial ligands most conducive to near-infrared phosphorescence. Disappointingly, the phosphorescence quantum yield invariably turned out to be very low, about 0.02 - 0.04% at ambient temperature, with about a two-fold increase at 77 K. Phosphorescence decay times were found to be around ~5 µs at 295 K and ~10 µs at 77 K. Fortunately, two of the Ir[TpCF3PC)]L2 derivatives, which were tested for their ability to sensitize singlet oxygen formation, were found to do so efficiently with quantum yields Φ(1O2) = 0.71 and 0.38 for L = py and 4pa, respectively. Iridium corroles thus may hold promise as photosensitizers in photodynamic therapy (PDT). The possibility of varying the axial ligand and of attaching biotargeting groups at the axial positions makes iridium corroles particularly exciting as PDT drug candidates
Practical monitoring of the clinical efficacy of sinquanon in patients on antibiotic therapy
For more than seven decades, antibiotics and chemotherapeutics have been used successfully to treat and prevent infectious diseases, extensively changing the prognosis of severe infections and helping to improve quality of life. In the last two decades, the key role of the intestinal microbiota (IM) in basic vital functions such as digestion, protection against pathogens, and maintenance of immune and metabolic homeostasis has been recognized. Antibiotics do not selectively attack pathogenic bacteria. They have an effect on the normal microflora and can lead to imbalance inside the body (dysbacteriosis) and the development of opportunistic infections. Taking a probiotic during antibiotic treatment is one of the approaches to prevent antibiotic-associated diarrhea and other adverse effects of antibiotics when their use is necessary. In the present practical monitoring we want to share our results from the application of Sinquanon® to neutralize the negative effect of antibiotic treatment on the microbiome
Epiglottitis
Острият епиглотит (остър супраглотисен ларингит) е стенозиращо гръкляна възпалително заболяване, което изисква адекватни мерки и мероприятия за овладяването му. Боледуват предимно деца на възраст между 1 и 6 години. Острото начало, бързото протичане и прогресивно развиващият се задух изискват транспортирането на детето с линейка на „Бърза помощ“ в специализирано отделение за евентуални интубация или трахеотомия. Без контрол на състоянието на дихателните пътища и медикаментозно лечение симптомите могат бързо да прогресират до дихателна обструкция и смърт в рамките на няколко часа. Най-честият причинител на острия епиглотит е Haemophylus influenza тип B. Изолирани са и други патогенни микроораганизми като стрептококи, стафилококи и пневмококи. Не е изключено да се касае за първична вирусна инфекция с бактериална суперинфекция.------------------------------------------------------Epiglottitis is an acute inflammation in the supraglottic region of the oropharynx. It is a medical emergency in the otorhinolaryngology, which requires adequate measures to manage it. Acute epiglottitis is most common in children aged 1-6 years. The acute onset, rapid course, and progressive dyspnea which are developing children requires transportation by ambulance in a special compartment for possible intubation or tracheotomy. Without airway control and medical management, symptoms may rapidly progress to respiratory obstruction and death in a matter of hours. The most common cause of acute epiglottitis is Haemophylus influenza type B, although some cases are attributable to Streptococcus pneumoniae, Streptococcus agalactiae, Staphylococcus aureus, and Streptococcus pyogenes. It may also be caused by viruses related to upper respiratory infections
Spectral gap of segments of periodic waveguides
We consider a periodic strip in the plane and the associated quantum
waveguide with Dirichlet boundary conditions. We analyse finite segments of the
waveguide consisting of periodicity cells, equipped with periodic boundary
conditions at the ``new'' boundaries. Our main result is that the distance
between the first and second eigenvalue of such a finite segment behaves like
.Comment: 3 page
Dynamic screening of a localized hole during photoemission from a metal cluster
Recent advances in attosecond spectroscopy techniques have fueled the
interest in the theoretical description of electronic processes taking place in
the subfemtosecond time scale. Here we study the coupled dynamic screening of a
localized hole and a photoelectron emitted from a metal cluster using a
semi-classical model. Electron density dynamics in the cluster is calculated
with Time-Dependent Density Functional Theory and the motion of the
photoemitted electron is described classically. We show that the dynamic
screening of the hole by the cluster electrons affects the motion of the
photoemitted electron. At the very beginning of its trajectory, the
photoemitted electron interacts with the cluster electrons that pile up to
screen the hole. Within our model, this gives rise to a significant reduction
of the energy lost by the photoelectron. Thus, this is a velocity dependent
effect that should be accounted for when calculating the average losses
suffered by photoemitted electrons in metals.Comment: 15 pages, 5 figure
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