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We consider a nonstationary problem of determination of temperature in a circular concentric cylindrical channel of infinite length with thermally insulated surfaces filled with a moving medium under the influence of inductive heating of a conductor in the form of a cylindrical helical line (helix) synchronously rotating about the axis of symmetry of the channel. Problems of this kind are encountered in the process of thermal treatment of biomaterials with the use of the pyrolysis reaction when the helical surface of an auger moving a material mixture is inductively heated by electromagnetic fields. We solve these problem by using the Laplace integral transform with respect to time, Fourier integral transform with respect to the axial coordinate, and Fourier-Bessel expansions with respect to the angular and radial coordinates. It is shown that the temperature in the channel is, as a rule, described by a linearly increasing function of time. Weak oscillations caused by the rotation of the heated helix are imposed on this component. Low-amplitude oscillations of temperature are described by double Fourier-Bessel series whose coefficients are determined via the roots of a transcendental equation containing cross products of the derivatives of Bessel and Neumann functions. These roots are numerically determined by the 'regula falsi' method. The numerical analysis reveals a substantial influence of the radius, pitch, and the angular rotational velocity of the helix, and the linear velocity of the medium in the channel on the formation of space and time characteristics of the microstructure of temperature field. In particular, we establish the conditions leading to the resonant amplification of the amplitude of quasimonochromatic oscillations of temperature in the channel. Keywords: auger reactor, auger spiral, electric heating, nonstationary temperature field, mathematical modeling, numerical analysis., Introduction The problem of improvement of the technological processes of pyrolysis processing of various types of wastes and biomasses explains the necessity of comprehensive model and experimental investigations in this [...]

Author(s): S. S. Savinov [sup.1], A. I. Drobyshev [sup.1] Author Affiliations: (1) grid.15447.33, 0000 0001 2289 6897, Institute of Chemistry, St. Petersburg State University, , 199034, St. Petersburg, Russia Trace [...], Determination of macro- and trace elements in various biological fluids, including saliva and blood serum, is widely used for medical diagnostics and assessment of the impact of anthropogenic factors on human health. The most popular methods of spectral analysis have several disadvantages, including the need in sample preparation. As an alternative, we proposed a direct (without digestion) analysis of biofluids by arc atomic emission spectrometry using the dry residue method. The experimentally found optimal amount of the spectral buffer (0.15 mg of NaCl) and current strength (20 A) ensure a high-intensity analytical signal and a better limit of detection. The selected conditions also neutralize the effect of the saliva and serum matrix on the parameters of the arc plasma (temperature and electron concentration), which enables the use of standard aqueous solutions of element salts for plotting calibration curves. When 150 [micro]L of a whole saliva sample is applied to one end of the electrode, the limits of detection are at the level of no more than 1 [micro]g/L for Ag, Al, Cd, Cu, Fe, Mn, and Zn and several micrograms per liter for Cr, Pb, and Ti. No more than 50 [micro]L of blood serum can be applied to the electrode end face; the limits of detection, in this case, are three times higher. We assessed the accuracy of the determination of trace elements in real samples of saliva and blood serum. Additionally, a possibility of determining macroelements (Ca, Mg, P, Si) in saliva is demonstrated.

Author(s): Alexander P. J. Vlaar [sup.1], Joanna C. Dionne [sup.2] [sup.3] [sup.4] [sup.21], Sanne de Bruin [sup.1], Marije Wijnberge [sup.1] [sup.5], S. Jorinde Raasveld [sup.1], Frank E. H. P. van [...], Purpose To develop evidence-based clinical practice recommendations regarding transfusion practices and transfusion in bleeding critically ill adults. Methods A taskforce involving 15 international experts and 2 methodologists used the GRADE approach to guideline development. The taskforce addressed three main topics: transfusion support in massively and non-massively bleeding critically ill patients (transfusion ratios, blood products, and point of care testing) and the use of tranexamic acid. The panel developed and answered structured guideline questions using population, intervention, comparison, and outcomes (PICO) format. Results The taskforce generated 26 clinical practice recommendations (2 strong recommendations, 13 conditional recommendations, 11 no recommendation), and identified 10 PICOs with insufficient evidence to make a recommendation. Conclusions This clinical practice guideline provides evidence-based recommendations for the management of massively and non-massively bleeding critically ill adult patients and identifies areas where further research is needed.

Author(s): Fahimeh Jalali [sup.1], Zahra Hassanvand [sup.1], Ali Barati [sup.1] Author Affiliations: (1) grid.412668.f, 0000 0000 9149 8553, Department of Chemistry, Razi University, , Kermanshah, Iran Pharmaceutical analysis is a [...], A glassy carbon electrode modified with a nanocomposite consisting of carbon dots, hexadecyltrimethyl ammonium bromide and chitosan showed excellent electrocatalytic activity toward oxidation of mesalazine (MSA). Under optimal experimental conditions, hydrodynamic amperometry was used for sensitive determination of MSA. Calibration curve was obtained in the range of 0.1-10 [mu]M with a detection limit of 0.05 [mu]M. The repeatability of the method was studied for 5 replicate measurements of MSA (50 [mu]M) and the calculated relative standard deviation (RSD %) was 0.74%. The reproducibility for 5 different electrodes (expressed as RSD %) was 1.96% for MSA (50 [mu]M). The amperometric determination of the drug was successfully performed in spiked blood serum samples with recoveries ranging from 96 to 99%.

Author(s): Abdolhamid Hatefi-Mehrjardi [sup.1] [sup.2], Mohammad Ali Karimi [sup.1], Mahdiyeh Soleymanzadeh [sup.2], Azam Barani [sup.2] Author Affiliations: (1) grid.412462.7, 0000 0000 8810 3346, Department of Chemistry, Payame Noor University, , [...], A glassy carbon electrode has been modified by electrochemical polymerization of dianix yellow along with multi-walled carbon nanotubes (MWCNTs) and utilized for the selective determination of dopamine (DA), ascorbic acid (AA) and uric acid (UA). Atomic force microscopy and scanning electron microscopy images were obtained to compare the surface morphology and topography of the bare and modified electrodes. Also, the electrochemical activities of DA, AA, and UA on the bare and modified electrodes were evaluated with the use of cyclic, linear sweep and differential pulse voltammetry (DPV). Large peak separation, good sensitivity, and stability allow to apply the poly-dianix yellow/MWCNTs modified electrode for the determination of DA individually and in the presence of AA and UA. The DPV data showed the linearity of DA, AA, and UA peak currents in the concentrations ranges of 7-2500 nM, 5-110 [micro]M, and 0.100-7.500 [micro]M with the detection limits of 6.1, 99 and 8.9 nM, respectively. The proposed electrode was applied for the quantification of dopamine in human blood serum samples.

Author(s): Keiji Akamine [sup.1] , Marilynn Punaro [sup.1] [sup.2] Author Affiliations: (Aff1) grid.267313.2, 0000 0000 9482 7121, University of Texas Southwestern Medical Center at Dallas, , 5323 Harry Hines Blvd, [...], Recent advances have allowed better understanding of vasculitis pathogenesis and led to more targeted therapies. Two pivotal randomized controlled trials, RITUXVAS and rituximab in ANCA-associated vasculitis (RAVE), provide high-quality evidence demonstrating rituximab (RTX) is efficacious in inducing remission in adult ANCA-associated vasculitis (AAV) patients compared with cyclophosphamide (CYC). RAVE also demonstrated superiority of RTX to oral CYC for induction of remission in relapsing disease. Disappointingly, the RTX regimen was not associated with reduction in early serious adverse events. At least nine randomized trials are in progress, aiming to further delineate optimal dosing and duration of RTX therapy in AAV. In particular, the 6-month interim results of the PEPRS trial provide encouraging data specific to children. Due to special concerns related to growth, preservation of fertility, and potential for high cumulative medication doses, children with AAV should be considered as candidates for RTX even as a first-line remission induction therapy. Two randomized clinical trials have defined the role of infliximab in Kawasaki disease (KD), which appears to be as an alternative to a second infusion of intravenous immunoglobulin (IVIG) for treatment-resistant disease. Support for other biologics in the treatment of AAV or for biologics in the treatment of other vasculidities is largely lacking due to either unimpressive trial results or lack of trials. Except for the KD trials and the PEPRS, trials enrolling children remain scant. This review touches on the key trials and case series with biologics in the treatment of vasculitis that have influenced practice and shaped current thinking.

Author(s): Graeme MacLaren [sup.1] [sup.2], Alain Combes [sup.3], Robert H. Bartlett [sup.4] Author Affiliations: (1) grid.412106.0, 0000000406219599, Cardiothoracic ICU, National University Hospital, , 5 Lower Kent Ridge Rd, 119074, Singapore, [...], Background Extracorporeal membrane oxygenation (ECMO) has been used in clinical medicine for 40 years but remains controversial therapy, particularly in adult patients with severe respiratory failure. Over the last few years, there have been considerable advances in extracorporeal technology and clinical practice, ushering in a new era of ECMO. Many institutions adopted ECMO as rescue therapy during the recent H1N1 influenza pandemic, reigniting the controversy. Discussion Hollow-fibre oxygenators and Mendler-designed centrifugal pumps have replaced the old silicon oxygenators and roller pumps. The advantages of these novel systems and the principles that underlie their function are outlined. Advances in cannula technology allow greater ease of patient positioning, in some cases facilitating extubation and ambulation on ECMO. Improvements in ECMO circuitry have led to a reduction in heparin and blood product requirements, with consequently fewer complications. Greater understanding of severe acute respiratory distress syndrome has allowed clinicians to successfully support adults on ECMO for months at a time, as a bridge to either recovery or transplantation. Conclusions ECMO is safer, cheaper, and simpler than in previous eras. Both circuit and patient can be cared for by a single trained nurse. Additional prospective studies of ECMO for adult respiratory failure are underway. Contemporary ECMO in awake, potentially ambulant patients to provide short-term support for those with acute, reversible respiratory failure and as a bridge to transplantation in those with irreversible respiratory failure is now ready for widespread evaluation.

In connection with the ratification of the Convention and the beginning of the destruction of chemical weapons, the determination of chemical warfare agents (CWA) and their degradation products (DP) has [...], This review summarizes the results of high-performance liquid chromatography with mass-spectrometric detection (HPLC-MS) in the identification of chemical warfare agents and their degradation products, obtained in the last 13 years passed since the ratification of the Convention on the Prohibition of the Development, Production, Stockpiling, and Use of Chemical Weapons and on Their Destruction (the Convention). The conditions of the separation and detection of compounds in a variety of ionization techniques (electrospray ionization, atmospheric pressure chemical ionization) and analyzers (time-of-flight (TOF), tandem mass spectrometry, triple quadrupole, ion trap) are considered. The detection limits of the degradation products are given; the possibility of identifying compounds and the methods of sample preparation using contemporary methods of preconcentration (solvent microextraction) and separation (use of various adsorbents, molecularly-imprinted polymers) are described. The features of the HPLC-MS analysis of environmental samples (water, soil) and biological fluids (urine, blood serum) are discussed. The review is focused on the determination of the degradation products and derivatives of nerve agents, that is, alkylphosphonic acids. Keywords: high-performance liquid chromatography with mass spectrometric detection, chemical warfare agents, nerve agents, degradation products of chemical warfare agents, alkylphosphonic acids. DOI: 10.1134/S1061934812020025

Byline: Y. Ikeda (1), T. Sakemi (1), G. Nishihara (1), M. Nakamura (1), T. Fujisaki (1), T. Koh (1), Y. Tomiyoshi (1), S. Emura (1), K. Taki (2) Keywords: Key words Heat stroke; Multiple organ dysfunction syndrome; Blood purification therapy; Continuous venovenous hemofiltration; Plasma exchange Abstract: Five patients were admitted to our hospital because of classical heat stroke during the heat waves which attacked our country in the summers 1994 and 1995. The clinical and laboratory findings of all patients suggested the rapid progress of multiple organ dysfunction syndrome (MODS). Blood purification (BP) therapy, in addition to conventional treatment, was performed in three of the patients. Despite their disastrous general condition, all completely recovered or recovered sufficiently to be transferred to a rehabilitation hospital. Two additional patients were treated with conventional treatment only and both died in 1--3 days after admission.Clinical characteristics and laboratory findings on admission showed no differences between the cases receiving BP therapy and those not receiving BP therapy. These findings suggest that, in heat stroke patients, additional BP therapy may provide a better prognosis than conventional therapy only. These beneficial effects of BP may have been due mainly to the removal of proinflammatory cytokines related to heat stroke. Author Affiliation: (1) Departments of Internal Medicine, Saga Medical School, Nabeshima, Saga, 849--8501, Japan e-mail: ikeda-y@smsnet.saga-med.ac.jp Tel. + 81(952)31 65 11 Fax + 81(9 52)34 20 17, JP (2) Department of Critical Care Medicine, Saga Medical School, Saga, Japan, JP Article note: Received: 27 May 1998 Final revision received: 22 December 1998 Accepted: 22 December 1998