Fast photoprocesses in a symmetric indotricarbocyanine dye (hitc) in solutions

Spectral-kinetic and photochemical properties of HITC dye with iodide and perchlorate counterions have been studied in environments where the dye molecules exist in different ionic forms. In ethanol, the dye molecules exist as free ions; in dichlorobenzene, as contact ion pairs. Superfast transformation of non-stationary spectra in an HITC dye bleaching band is found. The observed effects are interpreted within the framework of concepts on "burning out" a notch in the contour of a non-uniformly widened vibronic band of S0 → S1-absorption. Qualitative differences in recorded absorption spectra from the dye excited electronic states for weakly and highly polar solvents are found. It is shown that the observed differences are caused by superfast charge transfer in the contact ion pairs that results in the formation of free radicals

Апроксимація ДФВЗ кубічним поліномом

Розглянуто різні підходи апроксимації дистрибутивної функції відбивної здатності поверхні. Розроблено апроксимацію ДФВЗ, основану на використанні косинус-кубічної функції, що має численні переваги порівняно з поширеними сьогодні

Modern Approaches to the Diagnosis and treatment of <i>Clostridioides difficile (C. difficile)</i>-associated Disease in Adults (literature Review and Expert Council Resolution)

Aim: to review the modern approaches to the diagnosis and treatment of C. difficile-associated disease in adults and present the resolution of the Expert Council held on March 25, 2023 in Moscow.General provisions. C. difficile is the most important nosocomial pathogen which spores are also commonly found in the environment. Microbiota impairment, primarily due to the use of antibacterial drugs, is a key stage in the development of C. difficile-associated disease. A search for an infection should be carried out only in patients with diarrhea, and it is advisable to use at least 2 laboratory methods. The drug of choice for first-line treatment is vancomycin. If drug treatment is ineffective or the patient has recurrent clostridial infection, fecal microbiota transplantation should be considered. The probiotic strain Saccharomyces boulardii CNCM I-745 has a direct inhibitory effect on C. difficile toxin A, promotes normalization of the intestinal microbiota composition, and decreases the inflammatory reaction in colonic mucosa colonized with a toxigenic strain of C. difficile.Conclusions. Addition of the probiotic strain Saccharomyces boulardii CNCM I-745 to antibacterial therapy promotes both primary and secondary prevention of C. difficile-associated disease

Lowering the radioactivity of the photomultiplier tubes for the XENON1T dark matter experiment

The low-background, VUV-sensitive 3-inch diameter photomultiplier tube R11410 has been developed by Hamamatsu for dark matter direct detection experiments using liquid xenon as the target material. We present the results from the joint effort between the XENON collaboration and the Hamamatsu company to produce a highly radio-pure photosensor (version R11410-21) for the XENON1T dark matter experiment. After introducing the photosensor and its components, we show the methods and results of the radioactive contamination measurements of the individual materials employed in the photomultiplier production. We then discuss the adopted strategies to reduce the radioactivity of the various PMT versions. Finally, we detail the results from screening 216 tubes with ultra-low background germanium detectors, as well as their implications for the expected electronic and nuclear recoil background of the XENON1T experiment.Comment: 10 pages, 5 figure

Spin physics with antiprotons

New possibilities arising from the availability at GSI of antiproton beams, possibly polarised, are discussed. The investigation of the nucleon structure can be boosted by accessing in Drell-Yan processes experimental asymmetries related to cross-sections in which the parton distribution functions (PDF) only appear, without any contribution from fragmentation functions; such processes are not affected by the chiral suppression of the transversity function $h_1(x)$. Spin asymmetries in hyperon production and Single Spin Asymmetries are discussed as well, together with further items like electric and magnetic nucleonic form factors and open charm production. Counting rates estimations are provided for each physical case. The sketch of a possible experimental apparatus is proposed.Comment: Presented for the proceedings of ASI "Spin and Symmetry", Prague, July 5-10, 2004, to be published in Czech. J. Phys. 55 (2005

The COMPASS Experiment at CERN

The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.Comment: 84 papes, 74 figure

Diagnosis and Treatment of Irritable Bowel Syndrome: Clinical Recommendations of the Russian Gastroenterological Association and Association of Coloproctologists of Russia

Aim. Current clinical recommendations accentuate current methods for the diagnosis and treatment of irritable bowel syndrome (IBS).Key points. IBS is a functional bowel disorder manifested with recurrent, at least weekly, abdominal pain with the following attributes (any two leastwise): link to defecation, its frequency or stool shape. The symptoms are expected to persist for at minimum three months in a total six-month follow-up. Similar to other functional gastrointestinal (GI) disorders, IBS can be diagnosed basing on the patient symptoms compliance with Rome IV criteria, provided the absence of potentially symptom-causative organic GI diseases. Due to challenging differential diagnosis, IBS can be appropriately established per exclusionem, with pre-examination as follows: general and biochemical blood tests; tissue transglutaminase IgA/IgG antibody tests; thyroid hormones test; faecal occult blood test; hydrogen glucose/ lactulose breath test for bacterial overgrowth; stool test for enteric bacterial pathogens and Clostridium difficile A/B toxins; stool calprotectin test; abdominal ultrasound; OGDS, with biopsy as appropriate; colonoscopy with biopsy. The IBS sequence is typically wavelike, with alternating remissions and exacerbations often triggered by psychoemotional stress. Treatment of IBS patients includes dietary and lifestyle adjustments, various-class drug agents prescription and psychotherapeutic measures.Conclusion. Adherence to clinical recommendations can facilitate timely diagnosis and improve medical aid quality in patients with different clinical IBS variants

Interrelations between viral load and cellular immunity in patients with COVID-19 of varying severity

Assessment of viral load levels in various biological samples taken from the respiratory tract can be an indicator of an ongoing process of active viral replication and may be used to monitor severe respiratory viral infections. The study of the relationship between SARS-CoV-2 viral load and immunological laboratory parameters is an important step in the search for clinical markers of COVID-19.The aim of this research was to quantify viral load in patients with COVID-19 and to identify the relation-ship between viral load and changes in the parameters of the cellular component of the immune system.A laboratory examination was carried out on 74 patients diagnosed with COVID-19, they were divided into 3 groups based on the severity of the disease: mild, moderate, severe. Total viral load in clinical samples was determined by the number of SARS-CoV-2 RNA copies per 100 copies of the reference RNaseP gene.     A comprehensive assessment of the cellular component of the immune system was performed using flow cytometry and direct monoclonal antibodies, and the IL-6, and C-reactive protein concentrations were determined.We revealed a relationship between the development of serious clinical conditions in the patients with COVID-19, and the levels of viral load. High levels of viral RNA in biological samples correlate with main indicators of the T cell component of the immune system associated with disease severity. In a subgroup of patients with an extremely high viral load, strong positive correlations were found between the relative numbers of cytotoxic lymphocytes (CD3+CD8+), activated T lymphocytes (CD3+HLA-DR+), as well as absolute and relative numbers of activated B lymphocytes and NK cells (CD3-CD25+).Laboratory monitoring of the cellular component of the immune system, along with the assessment of viral loads, should improve  early assessment of clinical condition in the patients with COVID-19. Changes   in expression levels of activation markers on immune cells can be potentially viewed as indicators of recovery during COVID-19

Diagnosis and Treatment of Irritable Bowel Syndrome: Clinical Recommendations of the Russian Gastroenterological Association and Association of Coloproctologists of Russia

Aim. Current clinical recommendations accentuate current methods for the diagnosis and treatment of irritable bowel syndrome (IBS).Key points. IBS is a functional bowel disorder manifested with recurrent, at least weekly, abdominal pain with the following attributes (any two leastwise): link to defecation, its frequency or stool shape. The symptoms are expected to persist for at minimum three months in a total six-month follow-up. Similar to other functional gastrointestinal (GI) disorders, IBS can be diagnosed basing on the patient symptoms compliance with Rome IV criteria, provided the absence of potentially symptom-causative organic GI diseases. Due to challenging differential diagnosis, IBS can be appropriately established per exclusionem, with pre-examination as follows: general and biochemical blood tests; tissue transglutaminase IgA/IgG antibody tests; thyroid hormones test; faecal occult blood test; hydrogen glucose/ lactulose breath test for bacterial overgrowth; stool test for enteric bacterial pathogens and Clostridium difficile A/B toxins; stool calprotectin test; abdominal ultrasound; OGDS, with biopsy as appropriate; colonoscopy with biopsy. The IBS sequence is typically wavelike, with alternating remissions and exacerbations often triggered by psychoemotional stress. Treatment of IBS patients includes dietary and lifestyle adjustments, various-class drug agents prescription and psychotherapeutic measures.Conclusion. Adherence to clinical recommendations can facilitate timely diagnosis and improve medical aid quality in patients with different clinical IBS variants

ULF geomagnetic pulsations at different latitudes in Antarctica

We present a study aimed to characterize the ULF (1–100 mHz) geomagnetic pulsation activity in the polar cap at different latitudes. We used magnetic measurements obtained through 2005–2007 in Antarctica, at Dome C (89&amp;deg; S corrected geomagnetic latitude) and at Terra Nova Bay (80&amp;deg; S corrected geomagnetic latitude). The results indicate a solar wind control of the wave activity, more important at larger distances from the cusp, as well as a significant role of the local ionospheric conditions. The different position of the two stations, with respect to the cusp and closed field lines, is responsible for the observed different pulsation characteristics. At Terra Nova Bay, due to the approaching of the station to the cusp and closed field lines in the daytime, the ULF power is characterized by a maximum around noon; daytime pulsation events in the Pc5 frequency band are related to the fundamental field line resonances occurring at lower latitudes, while higher harmonics of the fundamental may account for the characteristics of Pc3–4 pulsations. In the nighttime, at Pc3 frequencies, the results suggest waves propagating sunward, possibly due to the transmission of upstream waves from the magnetosheath via the magnetotail lobes. At Dome C, near the geomagnetic pole and very far from closed field lines, the ULF power in any frequency band only shows an enhancement in the postmidnight sector, more pronounced for Pc3 pulsations. The ULF activity appears to be driven by processes occurring in the magnetotail: in particular, nighttime Pc3 pulsation events may be originated from upstream wave penetration through the magnetotail lobes